1990
Massachusetts Water Resources Authority · from the MWRA · 92 pages · 4.2 MB
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November 1990
The State of
BOSTON HARBOR:
1990
Massachusetts
Water Resources
Authority
Report 1990-01
Connor MS and Gibson V. 1990. The state of Boston Harbor 1990. Boston: Massachusetts Water
Resources Authority. Report 1990-01. 89 p.
EXECUTIVE SUMMARY
This report describes the environmental status of Boston Harbor as of 1990, and
summarizes its condition in a report card. For each factor evaluated, five grades are
recorded: one for the present condition and four for predicted conditions at various
stages in the remediation plan being put into effect by the Massachusetts Water
Resources Authority (MWRA). In 1992, sludge discharge to the harbor will cease;
in 1995, with completion of the new outfall, effluent discharge will be halted; in
2000, full secondary treatment will be implemented; and in 2005, the. CSO
remediation program will begin to yield benefits.
Throughout the report we find that environmental conditions vary from one part of
the harbor to another. In general, the Inner Harbor and parts of the northwestem
Outer Harbor are most affected by contamination, and the southeastern portions of
the Outer Harbor are least affected. The environmental status of the harbor is
assessed by examining four questions that respond to some common concerns:
¢ Js it safe to swim at harbor beaches?
* Is it safe to eat fish caught in the harbor?
« Are marine resources in the harbor satisfactorily protected
from pollution?
+ Is the harbor a resource that people can enjoy aesthetically?
Is It Safe To Swim In Boston Harbor?
We consider beach condition to be the best
Swimming Beaches indicator of the poor state of the harbor. On
average, most parts of the Inner Harbor
Now: D landward of the World Trade Center fail to
1992: D+ : meet microbial standards for swimming.
1995: C However, no swimming beaches are found
2000: C in these areas. The less impacted parts of the
2005: B harbor are along northern Dorchester Bay
beaches, particularly Pleasure Bay.
ES-]
Executive Summary
171 o 0 BD Y
KEY TO GRADES
Exceilent: Consistently maintains conditions characteristic of other clean coastal
sites. :
Good: Frequently exceeds Federal water quality standards and expectations for
an urban estuary.
Satisfactory: Complies with Federal water quality standards and meets
expectations for an urban estuary.
Poor: Sometimes fails to comply with existing standards or meet expectations for
an urban estuary; some uses of the harbor are maintained.
Falling: Consistently fails to comply with Federal! water quality standards or meet
expectations for an urban estuary; there Is obvious environmental
degradation, and uses of the harbor are lost.
REPORT CARD FOR Boston tacbor
NOW | 1992 | 1995 2000
2005
IS IT SAFE TO SWIM?
Swimming beaches , D D+ | C Cc B
IST SAFE TO EAT FISH ANDSHELLFISH? =
Shellfish: Pathogens D- | D C- | C- | B-
Fish: Organic contamination C- C- C- | C+] B-
Fish: Metal contamination B- B- B- B B+
ARE MARINE RESOURCES PROTECTED?
Sediment contamination D- D D C- | C-
Water quality: Oxygen Cc 1c B B | B
Water quality: Toxic contamination B- | B B+| B+] A-
Fish disease D- D D+] C- C+
Benthic communities D- D D C- C-
HOW DOES THE HARBOR RATE AESTHETICALLY?
Aesthetics ; D C- B- B- B+
OVERALL GRADE D+| C- | C | C+] B-
The Boston Harbor report card sums up our knowledge of present conditions and our hopes
for the future.
ES-2
Executive Summary
Pathogen contamination at swimming beaches will improve slightly in the outer
harbor channel after the cessation of sludge dumping. The completion of the
primary treatment plant will reduce the discharge of combined sewer
outflows (CSOs) by half; the remaining half of CSO cleanup awaits the completion
of facilities for treatment of CSO discharge in the next decade. The Boston Water
and Sewer Commission is actively eliminating illegal connections to stormwater
drains, but this may not be enough to make the entire harbor, particularly Quincy
Bay beaches, suitable for swimming after a moderate rainstorm.
In summary, the harbor is currently too contaminated for swimming about half of
the time; in the future, except for Wollaston Beach, the harbor should be
swimmable 95% of the time.
Is It Safe To Eat Harbor Fish and Shellfish?
Because of pathogen contamination, none of
Shellfish: Pathogens the shellfish beds in the harbor can be
harvested except by master diggers who take
Now: D- their harvest to cleansing plants for
1992: D purification in clean water. The Division of
1995: C- Marine Fisheries can usually find beds that
2000: C- meet standards for this type of harvesting
2005: B- when less than a quarter inch of rain has
fallen. The rate of improvement will be
similar to that described for beaches, except
that shellfish standards are stricter than swimming standards, so the harbor will not
achieve as high a level of compliance.
Throughout the harbor, concentrations of
Fish: Organic polychlorinated biphenyls (PCBs) in lobster
Contamination tomalley (or hepatopancreas) exceed the
standard established by the U.S. Food and
Now: C- Drug Administraton (FDA). Concentrations
1992: C- of PCBs in fish and shellfish sometimes
1995: C- exceed U.S. Environmental Protection
2000: C+ Agency (EPA) guidelines for risk
2005: B- assessment, as do concentrations of
. polynuclear aromatic hydrocarbons (PAH).
Most improvement will be associated with
the completion of the new outfall into Massachusetts Bay. The change will not be
large, however, because a reservoir of contaminants has accumulated in the
sediments.
ES-3
Executive Summary
The rate of change will be slow (5 to 10 years) because of the relatively long life
span of the marine organisms.
Fish: Metal
Contamination
Now: B-
1992: B-
1995: B-
2000: B
2005: B+
The same considerations mentioned for
organic contamination apply here, but the
magnitude of improvement will be even
smaller because the problem is less
significant. Metal concentrations are elevated
in fish and shellfish in the harbor, but not to
the extent that human health standards are
violated.
In summary, while shellfish purification may
still be required by the state, many more
shellfish beds should be open. The fish are
currently safe to eat, though not desirable because of organic contamination. This
contamination will slowly decline.
Are Marine Resources Protected?
Fish and bottom-dwelling (benthic) invertebrates were chosen to represent the
status of living resources in the harbor. These groups contain commercially
valuable species and are likely to exhibit the effects of living in a contaminated
environment. Contamination in both the water column and the sediments was
assessed because of the possible effect on these species.
Sediment
Contamination
Now:
1992:
1995:
2000:
2005:
OOU0Yg
Portions of Boston Harbor contain sediments ©
with some of the highest levels of organic
and metal contamination found in urban
harbors of the United States. In Hingham
and Hull Bays (the southeastern harbor),
contamination concentrations are only
moderate, whereas areas in the northwestern
and central portions of the harbor are
intermediate in degree of contamination.
Most of the improvements will be associated
with the completion of the new effluent
tunnel. It may take decades for concentrations of toxic contaminants in the
sediments to halve their current levels.
ES-4
Executive Summary
Because animals require oxygen for
Water Quality: respiration, dissolved oxygen is a standard
measure of water quality. Water in the Inner
Harbor occasionally fails to meet standards
for dissolved oxygen, but concentrations
rarely approach levels that can affect species
abundance. In the Outer Harbor, water
quality standards are generally met, but
concentrations of dissolved oxygen are
sometimes depressed. Because most of the
input of oxygen-consuming wastes is from
the sewage effluent and sludge, completion
of the outfall tunnel and sludge facilities will have the biggest impact on oxygen
concentrations in the water. The sediments contain a large residue of nutrients and
organic matter that may slow the rate of recovery.
; Water quality criteria for most of the EPA
Water Quality: Toxic priority pollutants are met most of the time.
Contamination This is particularly true in the Outer Harbor,
which is well flushed with water from
Now: B- Massachusetts Bay. The copper standard is
1992: B the one most likely to be exceeded, especially
1995: B+ in the Inner Harbor. Changes in priority
2000: B+ pollutant concentrations in the harbor should
2005: A- be similar to the improvement in oxygen
concentration noted above. .
Boston Harbor is noted for the high incidence
Fish Disease on fin rot and tumors in its winter flounder.
Improvements will be associated with the
Now: D- cessation of sludge discharge and the
1992: D completion of the new outfall. The large
1995: D+ reservoir of contamination currently in the
2000: C- sediment and the relatively long (5 to 10
2005: C+ years) life span of fish will slow the rate of
progress.
- Some areas of the Inner Harbor and
Benthic Winthrop Bay are nearly devoid of benthic
Communities animals, but large portions of the
southeastern Outer Harbor have quite active
Now: D- and diverse bottom-dwelling communities of
1992: D worms, clams, and crustaceans. If benthic
1995: D comunites are limited by the concentrations of
2000: C- toxic contaminants found in the sediments,
2005: C- their recovery should be as slow as that
described for sediment
ES-5
Executive Summary
ES-6
contaminants, Alternatively, benthic communities may be more affected by the
availability of oxygen for respiration, implying that they might recover more
rapidly.
We conclude that harbor water quality is surprisingly good for an urban harbor and
will show the most improvement over the next 15 years. The legacy of past
sediment contamination will continue to affect the organisms living in the bottom of
the harbor.
How Does the Harbor Rate Aesthetically?
SS] Discharge plumes from the treatment plants
Aesthetics have a noticeable odor and color, moreover,
in a recent cleanup, Boston Harbor beaches
Now. D had more trash per unit area than any other
1992: C- beaches in the State. On the positive side,
1995: B- the cessation of scum discharges has
2000: B- improved the overall look of the harbor. The
2005: B+ worst source of turbidity and odor will
disappear when sludge discharges cease.
Completion of the new plant will decrease
untreated overflows by half; the other half
will require completion of CSO facilities. Trash and debris washed into the harbor
with stormwater will remain a problem. Aesthetically, the harbor is currently
pean: however, it will improve dramatically as a result of the MWRA‘s
efforts.
What Is the Harbor's Overall Grade?
We rate the harbor currently as a "D+".
Within the last decade, the harbor was
certainly an "F". Although the quality of
swimming beaches, fish, and sediment
remains of concern, there is some evidence
that conditions have improved in the past
decade.
The fact that 10,000 gallons of scum are no
longer put into the water each day has vastly
improved the appearance of the harbor. The
concentrations of metals in the water column and in the sediments and of PCBs
inshellfish have decreased significantly. Fin rot and tumors in fish also appear to
be at their lowest levels in this decade.
Executive Summary
With the cessation of sludge discharge in 1992 and relocation of the outfalls to
Massachusetts Bay, the harbor should meet most established standards by the mid-
1990s. Changes in water quality should occur on a scale of months to years;
changes in sediment and fish quality on.a scale of decades. Improvement will come
more quickly to the Outer Harbor than to the Inner Harbor. .
What prevents the harbor form receiving an "A" grade in the future? Boston
Harbor may never again be pristine because of the commercial traffic that moves
through it, the continuing problem of stormwater runoff, and the legacy of past
particles residing in the sediment. Nevertheless, in the first decade of the new
century, the harbor should generally exceed water quality standard and be cleaner
than most urban estuaries are today. Thus, we give ita "B" at the end of the
project.
ES-7
CONTENTS
EXECUTIVE SUMMARY ES-1
PREFACE xi
1. THE PROBLEM AND THE PLAN
Overview of the Problem in Boston Harbor 1-1
Overview of the Plan for Cleanup of Boston Harbor 1-2
2. UNDERSTANDING THE PROBLEM
Sources of Contamination 2-1
Suspended Solids‘ 2-2
Oxygen-Consuming Organic Matter 2-2
Pathogens 2-4
Nutrients 2-4
Toxic Materials 2-6
Fate of Materials in the Harbor 2-6
Water Movement 2-8
Sediment Deposition 2-9
Resuspension, Transport, and Long-Term
Accumulation 2-10
3. IS IT SAFE TO SWIM IN BOSTON HARBOR?
The Outer Harbor 3-3
Effluent 3-3
Storm Drains 3-3
CSOs 3-4
Rivers 3-4
The Inner Harbor 3-4
4. IS IT SAFE TO EAT FISH AND SHELLFISH?
Bacterial Contamination in Shellfish 4-1 .
Toxic Contamination in Marine Animals 4-3
Fish 4-3
Mussels 4-5
Trends over Time 4-7
Bioaccumulation in Caged Mussels 4-10
Lobster 4-11
PCBs 4-11
PAHs 4-11
Metals 4-11
Summary 4-12
Disease in Fish and Other Animals 4-12
Contents
5. ARE FISH AND OTHER MARINE RESOURCES BEING
PROTECTED?
Water 5-2
Water Quality Criteria 5-2
Metal Contamination 5-2
Sediments 5-4
What Is the Extent of Sediment Contamination
in Boston Harbor? 5-7
How Do Boston Harbor Sediments
Compare to Other Urban Areas? 5-9
Are the Problems in Boston Harbor Getting
Better or Worse? 5-12
Fish 5-12
External Abnormalities 5-13
Boston Harbor Studies 5-15
Evidence for an Environmenta)
Connection 5-15
Internal Abnormalities 5-15
Boston Harbor Studies 5-15
Links between Disease and a
Contaminated Environment 5-16
Effects on Population 5-18
Benthic Animals 5-18
6. HOW DOES THE HARBOR RATE AESTHETICALLY?
Scum 6-1
Effiuent and Sludge 6-1
Turbidity 6-1
Algal Blooms 6-2
Floatable Debris 6-2
7. PRESENT AND FUTURE: A SUMMARY
Predictions for the Harbor’s Future 7-1
Cessation of Sludge Discharge 7-1
Effluent-Related Changes 7-1
CSO Control 7-3
Remaining Problems 7-4
Stormwater 7-4
Rivers 7-4
Sediment 7-4
Leaching of Hazardous Waste 7-5
The Boston Harbor Report Card 7-5
BIBLIOGRAPHY
ACKNOWLEDGMENTS
PREFACE
In this report, we provide information on the current condition of
Boston Harbor and the improvements that can be expected at different
stages of the remediation plan. Our intent is to give the informed
citizen an overview of the state of scientific knowledge about the harbor.
For more detailed information, contact the library of the Massachusetts
Water Resources Authority (MWRA) for copies of MWRA research
reports.
The report is organized around the issues we believe to be of most
interest to the concerned citizen. After summarizing some of the
information necessary to understand conditions in the harbor, we look
at four primary concerns expressed by the public: Is it safe to go
swimming in Boston Harbor? Is it safe to eat the harbor’s fish and
shellfish? Are fish and other marine resources being adequately
protected from the effects of pollution? What about the aesthetic
conditions—is the harbor a resource that people can enjoy?
As a way of summarizing the information, we grade the factors that
must be considered in answering the four questions. Each factor has
five grades, one representing the current state of the harbor and the
others predicting its state at various stages of remediation, In the final
section of the report, we compile all the grades into a report card for
Boston Harbor and explore the question of what the harbor will be ike
in the future. :
Like any assessment based on numerical ratings, this one is open to
debate. Just as no report card can give a three-dimensional portrait of
a child’s abilities and character, ours does not adequately represent the
complexities of Boston Harbor. We believe, however, that it serves a
purpose by highlighting the harbor’s strengths and weaknesses,
permitting comparison of various factors, and— perhaps most
importantly — stimulating debate on the picture that emerges.
The information in this report is drawn from many different sources.
The MWRA Harbor Studies Department supports and participates in
research efforts that involve cooperation between the Commonwealth
and a variety of public and private research institutions. In addition,
many studies with information relevant to the harbor have been or are
being conducted by other organizations. These studies include routine
monitoring performed by various State and local agencies, small-scale
reseatch by jocal universities or environmental organizations, and large
national programs funded by the Federal government. Institutions
xi
Preface
xi
Grading system used for the Boston Harbor report card
A EXCELLENT: Consistently maintains conditions characteristic of
other clean coastal sites (e.g., Provincetown Harbor).
B GOOD: Frequently exceeds Federal water quality standards and
expectations for an urban estuary (e.g., some of Puget Sound).
C SATISFACTORY: Complies with Federal water quality standards
and meets expectations for an urban estuary (e.g., San Francisco
Bay).
D_ POOR: Sometimes fails to comply with existing standards or
meet expectations for an urban estuary; some uses of the harbor
are maintained (e.g, Boston Harbor).
F FAILING: Consistently faiis to comply with Federal water quality
standards or meet expectations for an urban estuary; there is
obvious environmental degradation, and uses of the harbor are
lost (e.g., New York Harbor and New Bedford Harbor).
involved in long-term studies of harbor quality include the
Massachusetts Institute of Technology, the National Oceanic and
Atmospheric Administration (National Status and Trends Program), the
New England Aquarium, Northeastern University, the University of
Massachusetts at Boston, the U.S. Geological Survey, and the
Massachusetts Bay Program. MWRA’s Harbor Studies provides a
valuable service by synthesizing the results of these and other studies to
advance both the theoretical and the practical knowledge of conditions
in the harbor. This knowledge enables MWRA to make environmen-
tally sound and cost-effective decisions that benefit Boston Harbor.
Massachusetts Water Resources Authority
Harbor Studies Department
Charlestown Navy Yard
100 First Avenue
Boston, MA 02120
(617) 242-6000
L THE PROBLEM AND THE PLAN
Sewage sludge and
. effluent are
discharged to the
harbor with no
treatment beyond
the primary level
Contamination
from other sources
is also present
Overview of the Problem in Boston Harbor
Today, Boston Harbor receives the residue of household waste from
more than 2.2 million people in 43 communities in eastern
Massachusetts. In addition, businesses and industries in the
Metropolitan Boston area (about 5500 of them) flush still more waste,
of various kinds, into the sewer system and, ultimately, into the harbor.
By the standards current in the United States today, all of this waste
receives inadequate treatment. Boston is the only major U.S. city that
does not treat its sewage beyond the primary level. Primary processing
essentially separates sewage into two components, effluent and sludge,
by allowing it to stand until most of the solids (sludge) have settled out.
Disinfectant is then added to the liquid portion (effluent) to kill
bacteria. The irony is that, in Boston, both sludge and effluent end up
in the harbor anyway. :
The contamination in the sludge and effluent affect four issues of
concern to the public:
1. Is it safe to swim at harbor beaches?
2. Is it safe to eat fish caught in the harbor?
3. Are marine resources in the harbor satisfactorily protected from
pollution?
4. Is the harbor a resource that people can enjoy aesthetically?
These are the issues that are discussed in the following sections and
graded in the Boston Harbor report card.
Of course, sewage is not the only cause of the harbor's problems.
Materials carried by rivers, in water drained from land, and in fallout
from the atmosphere contribute their share to the total load of
contaminants. These sources are more difficult to identify, measure,
and contro! than sewage, but the Boston Harbor cleanup will not be
complete until they have been addressed in some way.
1-1
The Problem and the Plan
MWRA is required
by law to improve
its discharges to
the harbor
A phased plan
leads to full
secondary sewage
treatment by 1999
1-2
Overview of the Plan for Cleanup of Boston Harbor
The Massachusetts Water Resources Authority was formed in July 1985.
Its creation was a recognition of the fact that the problems in Boston
Harbor were not being solved by traditional means and existing
institutions. By that time, the Commonwealth of Massachusetts was
being sued in both State and Federal courts because of the poor
condition of the harbor. In response to these suits, MWRA has
negotiated a schedule for the harbor’s rehabilitation and is well on its
way to making those plans a reality (Figure 1.1).
MWRA’s plans to improve the quality of Boston Harbor have four key
components: (1) improvements to existing wastewater treatment
facilities, (2) construction of new facilities for wastewater treatment and
sludge processing, (3) capture and treatment of sewage that overflows
during rainstorms, and (4) reduction in the amount of toxic materials
put into the sewer system.
Construction of the new treatment facilities is the biggest part of the job
and will cost an estimated $6.1 billion. When the system is complete,
sewage will be pumped under the harbor from collection points, or
headworks, to a combined primary and secondary treatment plant on
Deer Island. This plant will have a capacity of 1300 million gallons
(4900 million liters) of sewage per day. The treated effluent will pass
through a 9,5-mile (15-km) tunnel bored through rock 400 ft (120 m)
below sea leve] and will be discharged through an outfall under 100 ft
(30 m) of water in Massachusetts Bay. The sludge will be disposed in
accordance with a plan that fully complies with environmental
protection and makes the best use possible of technology for beneficial
reuse of sludge. The disposal plan. will almost certainly call for some of
the sludge to be processed for use as fertilizer or soil conditioner,
_ Full secondary treatment will be put into operation in 1999. However,
the project is designed in stages so that some benefits will be available
more quickly.
The Problem and the Plan
Rea ASSES PRESS SNH BU FERRE
1988 89 90 ‘1 92 x) 94 95 96 ‘97 98 '99 2000
@ Discharge of scum from Deer Island ceases
Improve existing ‘facilities
@ Discharge of scum from Nut Island ceases
Permanent sludge facilities
begin operation
Interim facilities completed;
discharge of sludge to harbor ceases
nt facilities”
Full primary treatment begins
> Discharge of effluent
to harbor ceases
cilities
Full
secondary secondary
treatment begins treatment begins
Con
& Design and construct CSOs
Facilities plan submitted
— SER ASU KoREORED eee
1988 ‘89 90 1 92 93 94 95 6 ‘97 98 ‘992000
Figure 1.1. The schedule of milestones for the MWRA project reveals that the work is
designed in stages so that some benefits will be realized more quickly.
1-3
Nahant
Bay
Roads
Harbor President
Point
Central ign
Harbor
Figure 2.1. Based on-degree of contamination, Boston Harbor can be divided into four
broad areas: the Inner Harbor and the northwest, central, and southeast Outer
Harbor.
2. UNDERSTANDING THE PROBLEM
Harbor conditions
are not uniform;
useful divisions are
the Inner Harbor
and the northwest,
central, and
southeast Outer
Harbor
Effluent and
Sludge are major
sources of five
types of
contamination
to the harbor
Boston Harbor, shown in Figure 2.1, covers approximately 47 square
miles (122 km?) of bays and tidal estuaries. The water is shallow, from
1 to 10 m, except for depths reaching 20 m in President Roads and
Nantasket Roads, the two shipping channels. A number of small islands
are scattered throughout the harbor.
The harbor is customarily separated into two main areas, an Inner
Harbor and an Outer Harbor. The Inner Harbor extends from an
imaginary line connecting Castle and Governors Islands to the lower
reaches of the Charles, Mystic, and Chelsea Rivers. The Outer Harbor
covers the rest of the area, out to a line extending from Deer Island to
the tip of Hull. Because a main point of this report is that conditions in
Boston Harbor vary from one place to another, we have further divided
the Outer Harbor into northwest, central, and southeast sections. The
northwest takes in Dorchester Bay and President Roads, the central
portion includes Quincy Bay and Nantasket Roads, and the southeast
comprises Hingham and Hull Bays.
Sources of Contamination
The first thing that we need to know to understand conditions in Boston
Harbor is where the contamination is coming from. The major sources
of contamination to the harbor are effluent, sludge, combined sewer
overfiows (CSOs), rivers, stormwater, and the atmosphere. In general,
effluent and sludge are major sources of all the contaminants of primary
concern in the harbor. Contributions by CSOs, rivers, and stormwater
can also be significant for certain contaminants. Deposition from the
atmosphere is an important source for a few materials, particularly lead.
Industrial discharges that go directly into the harbor (or to a river that
feeds into the harbor) are relatively unimportant compared to these
other sources.
The materials of primary concern as contaminants in Boston Harbor lie
in five main categories:
Suspended solids
Oxygen-consuming organic matter
Pathogenic organisms, such as certain bacteria and viruses
Nutrients
Toxic materials.
RYN
©
Understanding the Problem
Toxic materials
attach to particles
in the water and
can accumulate in
areas of sediment
deposition
Decay of organic
matter depletes
oxygen in the water
These materials have different major sources (Figure 2.2). In general,
however, effluent and sludge discharged into the harbor after passing
through MWRA’s two primary treatment plants are major sources of all
groups of contaminants except pathogens.
Suspended Solids
The solid materials suspended in coastal waters such as Boston Harbor
can originate from natural as we}] as manmade sources. Naturally
occurring particles include inorganic materials, such as sand and clays;
living organisms, such as bacteria and phytoplankton; and organic
detritus. Sewage effluent is by far the most significant contributor of
suspended solids to Boston Harbor, followed by sludge.
An important reason for concern about suspended solids is that toxic
materials such as metals and organic compounds tend to adsorb to
particles of inorganic and organic matter, and thus become concentrated
on the particles. These particles are transported by water movements in
the harbor unti] the speed of the current slows enough to allow them to
settle to the bottom. Areas of settlement, or deposition, may
accumulate contaminants associated with the particles. Other potentially
adverse effects include oxygen depletion (discussed under Oxygen-
Consuming Organic Matter, following); reduction in productivity of the
area because the penetration of light into the water is reduced and
retards phytoplankton growth; and burial of bottom-living animals by
particle deposition. Furthermore, water with a heavy load of suspended
material is murky and unattractive.
Oxygen-Consuming Organic Matter
Biochemical oxygen demand (BOD) is a widely used measurement of
pollution from organic sources such as sewage. The measurement is
based on the fact that, when it is oxidized by microorganisms, organic
material decomposes and, in the process, uses up oxygen in the water
around it. Thus, in an area that contains a great deal of organic matter,
the water can actually be depleted of the oxygen necessary to support
marine life. As is the case for suspended solids, effluent is the leading
source of BOD for Boston Harbor, and sludge is the next most
important.
Understanding the Problem
Copper
(75,180 kg/yr)
Pofynuctear Aromatic
Hydrocarbons
(22,737 kyr )
WZ, Sludge Effluent ["_]) Alvers
Wl CSOs Stormwater Other
mtons: metric tons
Figure 2.2. Many sources cause harbor contamination. The other source takes in matter from
the air, groundwater, and discharges with permits from the National Pollutant
Discharge Elimination System. PAH estimates have the most uncertainty.
Understanding the Problem
High levels of
pathogens result in
posted beaches -
and closed
shellfish beds
CSOs are the
major source
of bacteria
to the harbor
Too much
nitrogen or
Phosphorus can
cause excess plant
growth, followed
by adverse effects
2-4
such as oxygen
depletion
Pathogens
The presence of pathogens, or disease-causing organisms, is difficult to
measure directly. Here, most of the values given refer to numbers of
fecal coliform bacteria. This group of bacteria is used as an indicator of
the presence of microorganisms that are likely to be associated with
sewage and are capable of causing disease in humans. Pathogen
contamination, as measured by indicator organisms, is periodically
responsible for the posting of health warnings at beaches in and around
the harbor and for the closure of shellfish beds to harvest for human
consumption. At present, some Boston Harbor beaches are posted
more than 50% of the time during summer, and all shellfish beds are
either closed or restricted to harvest in dry weather by licensed
commercial shellfishermen who must take the shelifish to a dépuration
plant for purification in clean water before they can be sold.
CSOs are the major source of bacteria to Boston Harbor. There are
more than 80 of these overflows, which, under certain conditions,
discharge untreated sewage into the harbor, in the area served by
MWRA (Figure 2.3). CSOs are active during rainstorms when water
from storm drains overloads the system. Pathogens can also be
discharged during dry weather, either because there are illegal
sewage connections to stormwater drains or because of broken or
obstructed pipes.
Nutrients
In marine waters, the primary nutrients are nitrogen and phosphorus.
At natural concentrations, these chemical elements are essential to fuel
the growth of phytoplankton, which forms the base of the marine: food
web. In excess amounts, however, these same necessary nutrients
become pollutants because they have adverse effects on the ecosystem.
An oversupply of nutrients can lead to a condition known as
eutrophication. In this condition, nutrients stimuiate plant growth until
there is an accumulation of algae, some of which may be undesirable
species, and which deplete oxygen from the water when they decompose.
In areas such as Boston Harbor, availability of nitrogen is the factor that
normally limits the growth of phytoplankton; thus nitrogen, in one form
or another, is the nutrient of greatest concern as a contaminant.
Sewage effluent is by far the leading source of nitrogen-based nutrients
to Boston Harbor. Sludge is a secondary source, followed by rivers,
CSOs, and stormwater. Effluent is also the major source of
phosphorus-based nutrients, with small contributions from the
other sources.
Understanding the Problem
Effluent Discharge
Sludge Discharge
Combined Sewer Overflow
@x0O
Massachusetts
Hingham
oy
SRR
Figure 2.3. Sewage outfalls, sludge discharges, and combined sewer overflows are located
throughout Boston Harbor.
2-5
Understanding the Problem
A large number
of metals and
organic
compounds are of
potential concern
as toxic
contaminants
PCBs and other
toxic materials can
build up in the
tissues of edible
marine animals
This report
concentrates on a
few representative
substances
Some
contaminants are
carried out of the
harbor; others
remain and are
deposited in
sediments
Toxic Materials
The toxic materials found in Boston Harbor can be subdivided into two
classes— metals and organic compounds. Metals of concern include
arsenic, cadmium, chromium, copper, lead, mercury, nickel, silver, and
zinc, Toxic organic compounds include a variety of chemicals with
industrial or household uses—for example, acetone, benzene, and
naphthalene; petroleum hydrocarbons, particularly the more toxic
polynuclear aromatic hydrocarbons (PAH); pesticides, and
polychlorinated biphenyls (PCB).
The major reason for concern about these materials is that, in addition
to their known toxic effects, many have a tendency to accumulate in
living tissue. Plants and animals living in an environment with even
small amounts of toxic chemicals can gradually build up contaminant
concentrations in their bodies. This effect is intensified when one plant
or animal is eaten by another, and the process is repeated up the Jeveis
of the food web. PCBs, for example, are of major interest to regulators
because they are potential carcinogens and have been shown to be
present in elevated levels in species prized as seafood. Metals are
known to have toxic effects in humans. For example, mercury and its
compounds can cause damage to the nervous system and, at higher
concentrations, can be fatal. Lead exposure can result in behavioral
disorders, brain damage, and death. In general, toxic chemicals have
also been implicated in disease and lesions in fish and shel}fish, and in
other adverse effects such as lowered reproductive success in some
species.
Despite the variety of chemical contaminants and their different origins
and uses, evidence suggests that many of these materials behave in a
similar way physically. For this reason, discussion here is limited to a
few representative substances. In Boston Harbor, the main sources of
toxic materials, which are frequently associated with particulate matter,
are sewage effluent, sludge, and rivers, as illustrated in Figure 2.2.
Toxic contaminants enter the MWRA sewerage system from industrial
and commercial discharges, residential discharges, and street runoff.
Fate of Materials in the Harbor
Having seen where most of the contaminants come from, we must look
at where they go once they enter Boston Harbor. As already discussed,
the major sources of contamination to the harbor are sewage effluent,
sludge discharge, and CSOs. The locations of the existing discharges
are shown in Figure 2.3. Contaminants from these sources tend to be
associated with fine particulate material because many toxic chemicals
and bacteria adhere to particles in the discharges or in the receiving
Understanding the Problem
How severe is the toxic contamination in Boston Harbor?
The severity of toxic contamination in Boston Harbor can be evaluated by considering (1) levels
of specific contaminants in effluent, water, and sediment, (2) the bioaccumulation of these
materials in marine animals, and (3) the toxicity of the effluent as a whole.
There is evidence that the amounts of specific contaminants being added to the harbor are
declining. MWRA routinely collects monthly samples of influent, effluent, and digested sludge
from its facilities. These samples are analyzed for the presence of toxic metals of concern. In
addition, at intervals, samples are taken for other pollutants, including PCBs and other organic
compounds, Analysis of these samples shows that, on average, the amount of metals entering
the two sewage treatment plants and then being discharged to Boston Harbor is about 75%
Jower than it was 8 years ago. For PCBs, compounds whose manufacture was banned in the
1970s, current levels are at least 100 times lower than 10 years ago. Three major factors have
contributed to the decline in the amount of toxic materials being added to Boston Harbor:
« MWRA has strengthened its controls on industrial and commercial discharges. Stricter
regulation includes establishment of local limits governing discharge of toxic materials, more
industria] inspections, and tougher enforcement.
¢ Public awareness of the problem has increased. Presentations by MWRA, harbor tours by
Save the Harbor/Save the Bay, exhibits at the New England Aquarium, and efforts by the
Conservation Law Foundation and Greenpeace have all played roles in public education.
¢ The Federal government has taken action on a national fevel. Manufacture of many of the
most toxic pesticides and other hazardous materials has been banned. In addition, EPA has
developed standards for its pretreatment program, which regulates the amount of toxic
materials that an industrial discharger can dispose through a sewer systern.
Bioaccumulation, the second method of judging toxic contamination, is studied in the harbor
through experiments using caged mussels placed near the effluent outfall and through other
studies that measure tissue levels in natural populations of animals. These studies are discussed
in Section 4. :
Finally, the toxicity of the discharged effluent can be assessed by exposing marine organisms,
typically algae or shrimp, to various concentrations of effluent for a standard period in the
laboratory, The concentration at which 50% of the organisms die is known as the LCS0. The
toxicity of Boston Harbor effluent ranked below the midpoint of 30 effluents, from other urban
sewage treatment plants, tested by EPA in 1989 —that is, the wastewater discharged by MWRA
was less toxic than half the other effluents tested. MWRA’s goal is to produce effluent with no
acute toxicity at all.
Understanding the Problem
Water circulation
in the harbor is
strongly influenced
by the tides; this
movement helps
to determine the fate
of contaminants’
The time that
dissolved materials
remain in the
harbor is estimated:
to be 1 to 2 weeks
2-8
water. Broadly speaking, two things can happen to these particles and
their associated contaminants —they can be flushed out of the harbor or
they can remain within its confines and eventually sink out of the water
and be deposited on the bottom.
Water Movement
We must know how the water moves to understand where particulate
matter ends up. The water circulation in the harbor is dominated by
the strong tides found in New England. The tides are magnified
because the natural resonance frequency of the Gulf of Maine/Bay of
Fundy system is close to the frequency of the Junar sernidiurnal tide.
Boston Harbor lies at the southeastern end of the Gulf of Maine;
although the tides, with an average range of 2.7 m, are smaller than
those in the Bay of Fundy, they are still large compared to those south
of Cape Cod.
Boston Harbor is generally very shallow. At mean low water, the
average depth is less than 3 m, except in President Roads and Nantasket
Roads, the shipping channels, Therefore, nearly half of the water in
Boston Harbor exits on an ebb tide. Based on the volume of the tidal
flow, the residence time (the time that the water remains in the harbor)
is about 1 or 2 days. However, the Inner Harbor and shallow areas of
the Outer Harbor are. flushed more slowly than the deep channels.
Numerical modeling and field studies conducted by the Massachusetts
Institute of Technology indicate that the residence time of dissolved
constituents in the harbor is 1 to 2 weeks.
Boston Harbor is an unusual estuary in that over half of its freshwater
inflow comes from sewage effluent, and this enters at the mouth rather
than the head of the estuary. The major rivers that discharge into
Boston Harbor are the Charles, Mystic, Chelsea, and Neponset; their
combined flow i is about 10 m/s. The effluent flow, by comparison, is
about 20 m/s.
There is little stratification (that is, vertical layering due to differences in
temperature and salinity) of the water in the harbor. Strong tidal
currents act to mix the harbor water, keeping stratification to a
minimum. The large volume of tidal flow must enter and leave the
harbor through the narrow, deep harbor entrances. Tidal currents of
50 cm/s have been measured in these shipping channels. Constriction of
this flow causes turbulent mixing, and the flow around the many harbor
islands also serves to mix the water.
The U.S. Geological Survey (USGS) has constructed a two-dimensional
mathematical model of the harbor, which, unlike previous models, can
A computer model
of the harbor helps
to understand
water movement
and predict
contaminant fate
Particles, and
associated
contaminants, are
eventually deposi-
ted to become part
of sediments
Understanding the Problem
resolve eddying motions and variations in currents due to flow around
the harbor’s complicated bathymetry.
Experiments with the USGS model, combined with field observations of
the sewage plume from Deer Island and tidal residual flow, indicate that
effluent-derived solids are being concentrated in the area of the Deer
Island Flats. On the ebb tide, the discharge from Deer Island is
effectively mixed with seawater in President Roads and carried out of
the harbor along the North Channel. Effluent discharged on the flood
tide enters the harbor and turns northward onto Deer Island Flats.
On the outgoing tide, sludge produced at the Nut Island Treatment
Plant is discharged into President Roads from an outfall at the tip of
Long Island. Field observations suggest that the sludge plume does not
move far from its discharge site, at least during calm weather. On the
flood tide, some of the sludge plume may return to the harbor. The
mode] predicts that, on the early part of the ebb tide, the sludge leaves
the harbor along the South Channel. Sludge discharged Jater in the ebb
stays near Long Island.
Comparison of the Nut Island sludge plume with the Deer Island plume
shows that the discharges behave very differently even though they are
released in the same narrow channel]. Drs. W.R. Geyer of the Woods
Hole Oceanographic Institution and R. Signell of the USGS suggest, on
the basis of current measurements in the channel, that the Nut Island
sludge is released in a stagnant region caused by coastline geometry.
The motion of the effluent plume from the Nut Island outfalls has also
been described. Discharges from these outfalls usually exit the harbor
through Nantasket Roads on the ebb tide and enter Hingham Bay on
the flood; however, the motion of this plume is influenced most by the
direction and strength of the wind. The USGS model predicts that
material from the Nut Island effluent plume remains in Hingham Bay
and Nantasket Roads. In general, the fate of sewage particles released
from the sludge and effluent outfalls is very sensitive to the phase of the
tide and the location of the outfall.
Sedimem Deposition
The distance that particles are carned with water movements depends
on the size of the particles and the strength of the currents. Eventually,
the particles settle out of the water and become part of the bottom
sediments. The distribution of sediment types on the harbor bottom
shows the effects of tidal currents. In President Roads and Nantasket
Roads, the strong currents scour the fine sediment away, leaving sandy
or gravelly sediments. Fine sediments are deposited on shatlow mud
2-9
Understanding the Problem
Many of the solid
particles from
sewage have been
shown to settle in
the harbor
The fate of
contaminants is
complex:
deposited particles
can be
resuspended and
move from their
2-10
initial settling
location
flats or in those deep areas that have less energetic circulation. Large
depositiona! areas are found over much of the southern half of the
harbor. Shallow areas around some of the harbor islands and some of
the mainland shoreline are also sandy, because wave action does not
allow fine sediment to accumulate. Areas in which the currents vary
considerably in time or space have. a combination of erosion and
deposition of fine sediments. Sediment texture is important in
determining not only the concentrations of contaminants in the
sediments, but also the type of animals that live there.
Any particles of effluent and sludge that are not transported out of the
harbor with the circulation described above will settle somewhere in the
harbor. A field study of sludge plumes from Deer and Nut Islands
included profiles through the plume to determine if the sludge reaches
the bottom in the vicinity of the discharges. The Nut Island sludge
outfall discharges in and near very shallow water, so the plume
essentially reaches to the bottom. Additional evidence comes from
measurements of spores of Clostridium perfringens. This bacterium is
found in the digestive systems of mammals and is excreted along with
waste products. Outside of the body, the bacteria form spores, which
make a good “tracer” for the presence of sewage, especially sludge,
because they are resistent to chlorination, persist in the environment for
a Jong time, and are easy and inexpensive to measure.
There is evidence that initial deposition of sewage solids from the
treatment plants occurs at the northern tip of Long Island and on Deer
Island Flats. No information is currently available about deposition of
solids from the Nut Island effluent discharge into Nantasket Roads.
Resuspension, Transport, and Long-Term Accumulation
Contaminated particles deposited close to their source may eventually
find their way to distant parts of the harbor, or even Out of the harbor,
by being resuspended and transported along the harbor bottom. This
may occur during particularly large tides or during storms. Solids will
ultimately tend to accumulate in depositional areas where tida) currents
are weak or where there are depressions in the seafloor. Transport and
depositional processes are very complex, producing heterogeneity in
distribution of contaminants and hot spots.of accumulated material.
To determine which areas of sediment deposition are affected by
sewage, MWRA has measured spores of the sewage tracer Clostridium
perfringens in the bottom sediments of the harbor (Figure 2.4).
Concentrations throughout the harbor are at Jeast 100 times higher than
Understanding the Problem
C. perfringens Spore Count
1°
= 10
RRRRRORERA = 10°
Values ore exponents (base 10)
of numbers per grom (dry w.}
Massachusetts
Peddocks
{sland
Figure 2.4. The spores of Clostridium perfringens show where sewage is being deposited in the
harbor. Figure adapted from SAIC (1990).
2-1h
Understanding the Problem
those found in Narragansett Bay, Rhode Island. Especially high levels
were observed near the Nut Island sludge discharge at the tip of Long
Island, on Deer Island Flats, in the Inner Harbor, and in Quincy Bay.
2-12
Pathogen
contamination at
harbor beaches is
monitored by the
MDC during the
swimming season
3. IS IT SAFE TO SWIM IN BOSTON HARBOR?
Most Boston Harbor beaches are not heavily used for swimming,
perhaps because of a perception that they are all polluted. Although
some harbor beaches, like Wollaston and Tenean, are posted with a
health warning more than 50% of the time, others, like Pleasure Bay,
are almost never posted (Figure 3.1), .
The Metropolitan District Commission (MDC) conducts a weekly
testing program at Boston Harbor beaches during warm weather. Until
1988, MDC analyzed samples for fecal coliform bacteria only; this
indicator group is described in Section 2. In 1988, the program was
expanded to also test for the presence of Enterococcus, another group of
bacteria found in the feces of warm-blooded animals and thus indicative
of the presence of sewage. Enterococci, like some viruses, are more
able to survive in salt water than are coliform bacteria. Numbers of
enterococci have been shown to correlate with rates of diseases
associated with swimming. When tests show that fecal coliform
concentrations exceed a geometric mean of 200 in each 100 milliliters of
What are the risks of swimming in seawater contaminated with
sewage?
The most common public health risk of swimming in seawater polluted
with pathogens from domestic wastewater is the possibility of
contracting gastroenteritis. Gastroenteritis is an infection of the
stomach and intestines; its symptoms include stomachache, diarrhea,
nausea, and vomiting, sometimes accompanied by a low fever. The
symptoms, although usually short-lived, can be violent, and the effects
can be severe in older people or in those who have other health
problems. Most cases of gastrointestinal illness associated with
seawater are attributed to a virus known as the Norwalk agent.
Because the symptoms tend to be self-limiting and the patient recovers
without medical attention, the actua] frequency of such illness is difficult
to estimate. More serious risks— including typhoid, hepatitis, dysentery,
and infections of the skin, eye, and ear—do exist; but again, it is
difficult to estimate their frequency.
3-1
Is it Safe To Swim in Boston Harbor?
PERCENTAGE TIME POSTED
50 100
Winthrop Beach
8%
7,
Constitution Beach
E RUERACEGRG Boe 55%
7,
Yirell Beach
Eg 8%
0%
Pleasure Bay : a Massachusetts
| 0% ra
Ma x f Boy 8
Carson Beach
Wollaston Beach
Si NLR LIES REE
ays,
REEF RENEON OR OMARECRORR %
RONNIE LOSER ROP
|
is 37 |
Figure 3.1. In 1989 and 1990, most of the major harbor beaches were posted as polluted at
Jeast once during the summer. Percentages represent the number of times
pathogen levels exceeded standards, divided by the number of times the beach
was tested.
‘Pathogen
concentrations are
affected by many
factors, but rainfall
increases the
likelihood of
contamination
At Outer Harbor
beaches, pathogen
conditions are
influenced by
different sources
Is it Safe To Swim in Boston Harbor?
water, or when enterococci are more abundant than 33 per 100 mL,
signs are posted warning that swimming may be hazardous.
Pathogen contamination is found in localized hot spots that are caused
by different factors, depending upon location. However, rainfall is a
triggering mechanism for beach pollution, whether the immediate source
is CSO discharge, stormwater, river influence, or effluent. It takes 3 to
4 days for the harbor to recover after a large rainstorm washes
pathogens into its waters. Beach contamination is also influenced by
water circulation in the area. Beaches in open areas swept by strong
currents are less likely to suffer from contamination than those in
enclosed or depositional areas. The factors that affect water quality are
complex, and we are stil] learning about how they interact to determine
conditions in a given location.
The Outer Harbor
In the Outer Harbor, sources of pathogen contamination include
effluent and sludge discharges, CSOs, storm drains, and river inflow.
The relative importance of different contamination sources differs from
beach to beach.
Effluent
Wollaston Beach can be affected by effluent discharge if heavy rains
cause some sewage going to Nut Island to bypass the treatment plant.
Sludge and effluent discharges may affect the harbor island beaches,
and may occasionally be carried to Malibu and Tenean beaches by tidal
currents.
Storm Drains
Many beaches that experience pathogen contamination are in proximity
to one or more storm drains. Although stormwater carries some
bacteria from land drainage, illegal sewage connections to storm drains
are the main origin of contamination. The Boston Water and Sewer
Commission is working to eliminate such illegal connections. Storm
drains are a major source of pathogens to Wollaston Beach, Tenean
Beach, and Constitution Beach, Figure 3.1 shows that water quality at
Constitution Beach improved in 1990, mostly because illegal connections
were eliminated.
3-3
Js it Safe To Swim in Boston Harbor?
The Inner Harbor
is often unsuitable
for swimming, but
a new goal for
water quality
signals interest in
improvement
CSOs and
Stormwater cause
most pathogen
contamination in
3-4
this area
CSOs
Water quality at Malibu, Constitution, and Tenean Beaches has
historically been affected by discharge from CSOs in these areas. Now,
however, treatment facilities have been installed near these three
locations to alleviate beach pollution. As mentioned above,
Constitution Beach shows improvement. At these facilities, waste is
screened and chlorinated before it is released to the harbor. In the
past, Wollaston Beach was also affected by a Jarge CSO on Moon
Island, but discharges from Moon Island are now much less frequent
and are chlorinated.
Rivers
In several rivers that flow into Boston Harbor, bacterial contamination
upstream of all CSOs is high enough to violate standards, but the source
of the problem is incompletely understood. Contamination from the
Neponset River is responsible for continuing problems at Tenean Beach.
The Inner Harbor
The State has recently reclassified water in the Inner Harbor from a
goal of Class SC (suitable for boating and fishing) to a goal of Class SB
(swimmable). Although there are no swimming areas in the Inner
Harbor, it is surrounded by residential areas, tourist attractions,
walkways, and parks; it is also heavily used for recreational boating.
The upgrade in classification reflects public interest in improving water
quality in this area.
Nevertheless, a study conducted by MWRA in 1989 to monitor water
quality and the effects of CSOs showed that most areas in the Inner
Harbor violated less stringent Class SC standards during wet weather.
Two areas, Fort Point Channel and a station in the lower Mystic River,
violated Class SC standards during dry weather as well. During dry
weather, much of the Inner Harbor had counts of indicator bacteria
below 200 colonies/100 mL (swimmable, or Class SB, standard), but the
high counts caused by wet weather meant that the Inner Harbor did not,
_ Overall, meet the swimmable standard.
In the Inner Harbor, CSOs are the major source of pathogens, followed
by stormwater. A major issue is whether contamination from the Inner
Harbor affects beaches in the Outer Harbor. Recent dye studies
showed that contaminated water, especially in Fort Point Channel,
stayed in the Inner Harbor long enough for a large proportion of the
pathogenic bacteria to settle and die off before they reached the Outer
Is it Safe To Swim in Boston Harbor?
Harbor. Inner Harbor water is diluted with reJatively clean Outer
Harbor water over the distance to the nearest beaches (Carson Beach
and Pleasure Bay). Thus, after an average storm, high bacterial counts
at beaches can usually be attributed to sources other than the Inner
Harbor.
REPORT CARD Now 1992 1995 2000 2005
IS IT SAFE TO SWIM?
Swimming beaches D D+ Cc Cc B
3-5
4, IS IT SAFE TO EAT FISH AND SHELLFISH?
Because of
pathogens, no
clam beds in
the harbor are
open for
unrestricted harvest
Harvesting with
depuration is
sometimes allowed
in selected beds
Another question of great interest to the public is whether fish and
shellfish from Boston Harbor are safe to eat. At present, some fish and
other animals in the harbor are diseased and some have high levels of
toxic or pathogen contamination.
Bacterial Contamination in Shellfish
There are extensive beds of soft-sheiled clams (Mya arenaria) in Boston
Harbor. At present, however, all of them are either entirely closed or
are restricted to harvest by master diggers who must subject the shellfish
they collect to a purifying procedure known as depuration. These
measures are required because of the high levels of pathogen
contamination, as measured by indicator organisms, found in the beds.
The State’s Division of Marine Fisheries (DMF) assesses levels of
pathogens in harvesting areas by monitoring indicator bacteria; that is,
bacteria whose presence is associated with sewage. DMF uses standards
established by the National Shellfish Sanitation Program. The program
is overseen by the Interstate Shellfish Sanitation Conference, and
incorporates action levels approved by the U.S. Food and Drug
Administration (FDA). These action levels specify that a harvesting
area must be closed if the geometric mean of the most probable
number (MPN) of fecal coliform bacteria, the indicator used, exceeds
14/100 mL or if more than 10% of the samples exceed an MPN of 43.
On any given day, DMF tries to locate at least three areas that can be
open for harvest with depuration—one area in the East Boston/
Winthrop region; one in Quincy Bay; and one in either Weymouth,
Hingham, or Hull. It is usually relatively easy to find an acceptable area
in Hingham or Hull, because these have the best overall water quality.
In Quincy Bay, the Jarge number of flats means that the odds are in
favor of finding one with acceptable pathogen Jevels. It is most difficult
to keep beds open in Weymouth, East Boston, and Winthrop.
Interestingly, the most productive beds are found on Bird Island Flats,
an area that is sometimes closed because of contamination by effluent
from Deer Island.
Even when fecal coliform contamination is low enough that beds are
open in all three areas, there is sti] one obstacle to harvesting. The
only place the shellfish can be taken to cleanse themselves of bacteria is
a depuration plant in Newburyport, and it can handle only 200 to 250
4-1
Is It Safe To Eat Fish and Shellfish?
Threat of some
types of disease
has been virtually
eliminated; other
illnesses can still
be contracted from
contaminated
shellfish
Proper cooking of
shellfish can
reduce the chance
of illness
4.2
Experience has shown that levels of pathogens in the harbor’s
_ Shellfish beds are directly related to rainfall
The Massachusetts Division of Marine Fisheries has formulated general
tules for the management of the shellfish resource in Boston Harbor.
These rules are based on studies of pathogen concentration after
rainfall. When the amount of rain is between 1/2 and 1 in., all beds are
automatically closed for at least 3 days. When the amount of rain
exceeds 1 in., the beds are closed for at Jeast 5 days. When an unusual
amount of rain falls in a short time, the beds are closed until testing
can demonstrate that pathogen concentrations have declined to an
acceptable level.
bushels of shellfish each day. Thus, the capacity of the purification
facilities may limit the number of acres open to restricted harvesting.
The answer to the question of whether it is safe to eat Boston Harbor
shellfish is complex, As a result of the State monitoring program,
legally harvested shellfish can be assumed not to have unsafe levels of
bacteria that have a direct association with sewage. For example, the
Shellfish Sanitation Program has virtually eliminated outbreaks of
typhoid fever, which was formerly the major disease caused by
consumption of contaminated shellfish.
Today, the most common illness from eating shellfish is gastroenteritis.
As noted in the section on swimming (Section 3), symptoms are usually
self-limiting — principally involving stomachache, diarrhea, and nausea,
with perhaps a low fever or vomiting—and seldom require medica]
attention. Microorganisms responsible for gastroenteritis include
bacteria belonging to the genus Vibrio, and viruses, especially the
Norwalk agent. Hepatitis A, a more serious, but rarer, viral illness, can
also be contracted from contaminated shellfish.
Studies suggest that the presence of viruses and vibrio bacteria does not
correlate well with the presence of fecal coliform bacteria, the indicator
organism on which routine testing is now based. There is also evidence
that depuration may not offer protection against illness from these
pathogens. However, the odds of contracting such illnesses are reduced
by proper cooking of shelifish. Although a clam will open after about a
minute of steaming, 4 to 6 min are needed to inactivate viruses. In
1986, the New England Journal of Medicine published an article
recommending that the practice of eating raw shellfish from any area
Winter flounder
are a good subject
for study of toxic
contamination
PCBs, PAHs, and
trace metals have
been investigated
in harbor flounder
Is It Safe To Eat Fish and Shellfish?
should be reconsidered in light of evidence that the risks are. higher
than previously realized.
Toxic Contamination in Marine Animals
Most studies of toxic contamination in marine animals have
concentrated on winter flounder, mussel, and lobster. A few other
species (other bivalves such as oyster and soft-sheJled clam; crab; and
other fish) have been examined in some studies, but not consistently
enough to build a good information base. .
Fish
Winter flounder (Pseudopleuronectes americanus) are chosen for study
for a combination of reasons. First, they are abundant and thus easy to
sample. Second, they represent a significant resource —the recreational
fishery for this species is the largest fishery in the harbor. Third, because
of their living and feeding habits, winter flounder are susceptible to the
effects of a contaminated environment. Like all flatfish, winter
flounder, or blackback, live on the bottom, frequently burying
themselves in the sediments. They feed on small invertebrate animals
found on or in the sediments. Flatfish are exposed to contaminants
directly (from sediment particles taken in during feeding) and indirectly
(from their prey, which absorb contaminants as they feed). One
invertebrate, the polychaete worm Capitella capitata, is a common food
for bottom feeders and is able to tolerate contaminated environments.
This species is found in abundance on the Deer Island Flats, which are
near the Deer Island outfall that discharges sludge and primary éffluent
into Boston Harbor. Flatfish, because of their lifestyle, are more
susceptible to adverse effects and disease due to contaminated
sediments than are roundfish (e.g., silver hake) that.live and feed in the
water column.
The contaminants that have received the most attention in Boston
Harbor are polychlorinated biphenyls (PCBs), polynuclear aromatic
hydrocarbons (PAHs), and trace metals. Three investigations (EPA’s
Quincy Bay study, and studies performed for the National Oceanic and
Atmospheric Administration [NOAA and the Massachusetts Division of
Marine Fisheries) compared levels of PCBs in winter flounder tissue
between fish in Boston Harbor and areas farther offshore. All found
higher levels in harbor flounder than in offshore specimens. The EPA
and NOAA studies examined PAH tissue concentrations in flounder
from the harbor and found them to be very low (< 10 ppb) or below
the detection limits of the analysis. The EPA study also looked at
sediment PAHs and found very high concentrations at two of the sites
4-3
Is It Safe To Eat Fish and Shellfish?
The question of PAHs in harbor sediments and seafood
Polynuclear aromatic hydrocarbons (PAH) are natural components of
petroleum, but are also formed by the incomplete combustion of
hydrocarbons or by the breakdown of hydrocarbon compounds by
ultraviolet radiation. PAHs occur naturally in many plants and in fossil
fuel and are produced as a result of burning of coal, oil, gasoline, wood,
and other fuels. The main source of PAH to the harbor is the
combustion of fossil fuels. In the Inner Harbor, petroleum (from waste
oil, spills, etc.) is also a significant source of PAH.
Certain PAH compounds are known to cause cancer in man and
animals. Early studies described tumors in chimney sweeps and coke-
oven workers. Although not all PAHs have known carcinogenic effects,
the EPA Quincy Bay study reports that there is sufficient evidence for
five PAHs identified in seafood from Boston Harbor to be classed as
carcinogenic to animals. These five are benzo(a)anthracene,
benzofluoranthene, benzo(a)pyrene, indeno(1,2,3-c,d)pyrene, and
dibenz(a,h)anthracene. There is some evidence that PAHs are
associated with the development of tumors in fish.
The fact that high levels of PAHs have been found in sediments at the
bottom of Boston Harbor is cause for concem about whether local
seafood species are accumulating these potentially hazardous chemicals
in their tissues. Because PAHs are metabolized by fish and Jobster, the
absence of these compounds does not always indicate safety because
some of the metabolites may be toxic.
sampled (near Moon and Nut Islands). The authors hypothesized that,
because PAHs are metabolized rapidly by fish, tissue concentrations
may not be a good indicator of exposure. In the one study (EPA) that
examined selected trace metals, levels were relatively low in all samples
of flounder tissue.
EPA judged the _ EPA also assessed the potential public health implications of
risk of eating consumption of seafood from Quincy Bay. It was concluded that
Quincy Bay consumption of “typical” amounts of flounder (less than 10 meals per
seafood to be — year) had risks similar to other eating and drinking activities. Even
average when PCB levels were elevated in the tissue of food species,
concentrations were less than the 2 ppm set as a standard by the FDA.
4-4
Mussel Watch
studies monitor
toxic contaminants
in shellfish
Both NOAA and
the New England
Aquanum have
Mussel Watch sites
in Boston Harbor
Four years of
NOAA Mussel
Watch data reveal
only one temporal
trend at harbor
sites: PCBs
declined at Deer
Island
Is It Safe To Eat Fish and Shellfish?
Mussels
Until the inception of the Mussel Watch Project established by NOAA
as part of the National Status and Trends (NS&T) Program, data
regarding contaminants in shellfish in Boston. Harbor were relatively
patchy with respect to species covered, locations, and chemicals. The
NOAA Mussel Watch Project began sampling bivalves at selected sites
on the east and west coasts of the United States in 1986. Four sites
were established in the Boston Harbor area: one near the Deer Island
sewage outfall, one in Dorchester Bay, one in Hingham Bay, and one at
Outer Brewster Island. Samples of the blue mussel (Mytilus edulis) have
been collected once annually since the late winter of 1986 and analyzed
for several organic contaminants and trace metals.
In 1987, the New England Aquarium began its own Mussel Watch
research, establishing three sites, including the same Outer Brewster
Island site being monitored by the NOAA project, and two additional
sites, one near the Central Wharf and one at Peddock’s Island.. A
reference site near Nahant is also sampled. The Mussel Watch: studies
have provided the first comprehensive overview of the status of.
contaminants in Boston Harbor shellfish populations. Figure 4.1 shows
Mussel Watch sites for both the NS&T and New England Aquanum
programs.
Just how contaminated are Boston Harbor shellfish? Based on
measurements of contaminants in fish, shellfish, and sediments by an
earlier (1976-1978) U.S. EPA Mussel Watch Program and the first 2
years of the NS&T Program, Boston Harbor was accused of being the
most polluted harbor in the country. To examine the validity of this
conclusion, we have used the mean contaminant concentration for the
past 4 years as a baseline against which contaminant concentrations may
be compared among sites and with other sites around the country.
This is a reasonable approach because no temporal trends have been
detected in any contaminant in mussels at any of the Boston Harbor
sites except for a significant decline in PCB concentrations at the Deer
Island site over the past 4 years. The mean concentrations can also be
compared to results of earlier measurements of contaminants in Boston
Harbor shellfish to assess possible long-term changes in contaminant
loads in the Harbor’s shellfish.
Table 4.1 shows the mean concentrations for five organic contaminant
groups and 11 metals monitored annually at the four Boston Harbor
NS&T sites. For general comparison, the table also shows regulatory
action levels established by the FDA, where they exist. When levels of
contamination exceeding the action level are found in a food species
from a particular area, FDA issues either a warning or an advisory
(depending upon the circumstances) to alert the public to risks
45
Is It Safe To Eat Fish and Shellfish? .
SY
sii
Dorche:
NE Aquarium
© Central Wharf ® Deer Island
@ Peddocks Island @® Dorchester Bay
© Outer Brewster Island @ Hingham Bay
© fast Point, Nahant © @) Outer Brewster Is.
©
Figure 4.1. Mussel Watch sites monitor the status of contamination in Boston Harbor
shellfish.
In general, mussels
at all harbor sites
have similar levels
of contamination
Boston is among
the nation’s most
contaminated sites
for 25% of the
contaminants
‘Concentrations of
PCBs seem to be
declining in the
harbor
Is It Safe To Eat Fish and Shellfish?
associated with consumption of that type of seafood. At present, such
standards have been set for only a few substances. For other
contaminants, the table shows values based on standard EPA methods
for assessment of health effects.
PCB values must be interpreted with some caution because the
analytical method used in the NS&T Program yields a total PCB value
that is about half that obtained by the method used by FDA to set
standards.
Table 4.1 also shows that, except for low molecular weight PAHs (from
a petrogenic source such as oil) in Deer Island mussels and lead in
Dorchester Bay mussels, the sites are very similar. Furthermore, results
of metal analyses in mussel] tissue from the New England Aquarium
Mussel Watch study are generally similar to those of the NS&T
Program. For the years 1987, 1988, and 1989, concentrations of silver,
cadmium, chromium, and zine are comparable in mussels collected for
both programs at the site that they share in the Outer Brewster Islands.
Copper results in the New England Aquarium study tend to be
somewhat lower, probably because the Aquarium depurates thé mussels
before analysis, whereas those collected for the NS&T Program are
analyzed with full guts that may be high in copper because of the
elevated copper content of the sediments.
The fact that results from all sites are quite comparable is worrisome in
one respect. The sites range ftom a location in the Inner Harbor all the -
way to a reference site near Nahant, but the more distant locations are
not demonstrably less contaminated. This suggests that, even when
sources of contamination are reduced, improvements in metal
contamination will not be detectable for a long time. Changes in
organic contaminants, on the other hand, are more likely because the
amount of contamination is higher compared to pristine sites.
Table 4.2 illustrates how Boston Harbor sites compare to other NS&T
sites nationwide (209 sites). On a national scale, Boston Harbor sites
appear on the top 10 most contaminated list for only 4 of the 16
contaminants examined (low molecular weight PAHs, PCBs, Jead, and
mercury).
Trends over Time: As stated earlier, no trends over the last few years,
except for the downward trend in PCBs, have been detected through
either the NS&T or New England Aquarium programs. Because of the
inconsistency in species, sampling seasons, and probable changes in
analytical technique, it is difficult to make meaningful comparisons of
NS&T or Aquarium data with results of earlier shellfish contamination
studies in Boston Harbor. Some comparisons, however, might be
4-7
Is It Safe To Eat Fish and Shellfish?
Table 4.1. Mean concentrations (ppm dry weight) of selected contaminants in mussels
collected at four NS&T sites in Boston Harbor from 1986 through 1989 are very
comparable,
Contami- Deer Dorchester © Hingham Brewster Comparative
nant Island Bay Bay Islands Value"
LMW PAH 2.0 16 0.9 1,0 43 (EPA)?
HMW PAH 17 18 1.2 0.8 NA
PCB 0.7 14 0.8 0.6 2 (FDA)
DDT 0.1 0.1: 0.1 0.1 5 (FDA)
Dieldren 0.02 0.02 0.01 0.01 . 03(FDA)
Silver 11 1.0 1.0 0.7 NA
Arsenic 9.0 93 8.7 10.4 11 (EPA)
Cadmium 14 15 1.0 12 11 (EPA)®
Chromium 7 2.6 1.8 21 54 (EPA)*
Copper 12.0 14.6 11.5 10.5 430 (EPA)*
Mercury 03 02 0.2 0.2 1 (FDA)!
Nickel 0.8 1 14 Li 215 (EPA)
Lead 73 13.8 8.7 63 NA
Selenium 15 19 19 1.9 3 (EPA)
Tin 0.4 03 02 03 6460(EPA)®
Zinc. 122.4 121.9 109.2 132.5 2150 (EPA)
LMW PAH: low molecular weight PAH; HMW PAH: high molecular weight PAH; NA: not
available,
EDA values are regulatory action levels; EPA values are target levels (used for comparative
evaluations only) calculated using Risk Reference Dose chronic values. Both are parts per
million wet weight.
>Based on naphthalene.
Risk Reference Dose for food.
$Chromium IV. .
From drinking water.
fOrganomereury.
Inorganic tin.
4-8
Is It Safe To Eat Fish and Shellfish?
relevant. For example, comparison of PAH and PCB results from the
NS&T samples collected at Deer Island from 1986 through 1989 with
results from the earlier EPA collections at the same site shows that
PAH and PCB concentrations were somewhat lower in 1976 and 1977
than in 1986 and 1987, respectively. There has been no major shift in
PAH concentrations in mussels at Deer Island since 1976, but the
decreasing trend in PCB levels since 1986 is apparent in Figure 4.2.
Table 42. Boston Mussel Watch sites are compared to the 10 most
contaminated sites nationwide. No Boston site ranked in
the top 10 for DDT, dieldrin, arsenic, chromium, copper,
nickel, selenium, silver, tin, zinc, or high molecular weight
PAH.
Mercury Lead
Tampa Bay, FL
Hudson - Raritan Upper Bay, NY
San Miguel Island, CA
San Francisco Bay, Emeryville, CA
Papys Bayou, FL
Matagorda Bay, TX
Moriches Bay, NY
Honolulu Harbor, HI
San Francisco Bay, San Mateo, CA
Deer Island, MA
PCBs
Buzzards Bay, Angelica Rock, MA
Hudson - Raritan Lower Bay, NY
Buzzards Bay, Round Hill, MA
Hudson - Raritan Upper Bay, NY
Sandy Hook, NJ
San Diego Harbor, CA
Throgs Neck, NY
Dorchester Bay, MA
Shark River, NJ
Galveston Bay, TX
Marina del Rey, CA
Salem Harbor, MA
Hudson - Raritan Upper Bay, NY
Dorchester Bay, MA
Monterey Bay, CA
Anaheim Bay, CA
Sandy Hook, NJ
Hingham Bay, MA
Throgs Neck, NY
Deer Island, MA
Low Molecular Weight PAHs
Panama City, FL
St. Andrew Bay, FL
Elliott Bay, WA
Hudson - Raritan Upper Bay, NY
Deer Island, MA
Dorchester Bay, MA
Jamaica Bay, NY
Throgs Neck, NY
Coos Bay, OR
San Diego Bay, CA
4-9
Is It Safe To Eat Fish and Shellfish?
ppm (Dry Weight)
PAH FDA PCB
PCB Standard
‘86 ‘87 ‘88 "89
Year
Figure 4.2. PCB concentration in mussels from Deer Island appears to have declined since
1986. No trend is apparent for PAHs. Data are from the NOAA NS&T Musse}
Watch program.
Mussels kept in
cages at outfall
Sites seem to
accumulate some
4-10
contaminants
Bioaccumulation in Caged Mussels: At least four studies have
investigated the rates at which mussels deployed at Boston Harbor sites
bioaccumulate selected contaminants in their tissues. These studies
were performed with mussels taken from uncontaminated areas and
suspended near outfalls at Deer Island, Nut Island, or both. After
intervals of about a month, tissue of mussels at the outfall sites was
compared with tissue from mussels at control sites.
In general, all of the studies showed some bioaccumulation for some
contaminants at some of the outfall sites. For metals, copper and zinc
increased in all four studies, Jead and mercury in three out of four, and
cadmium, nickel, and arsenic in two. Silver, chromium, and iron
increased in at least one study. For the organic compounds, PCBs
increased measurably in three studies, and results were inconclusive in
the fourth. PAH results were inconclusive in one study and not
investigated in a second; in the other two studies, however, PAHs were
found to accumulate at least slightly. Although variable, the results of
PCB
concentrations In
lobster muscle are
below the FDA
action level
PCB accumulation
is higher in lobster
tomalley than in
“muscle tissue
PAR
concentrations are
higher in lobster
than in fish
Among metals
Studied, copper,
Zinc, and mercury
had the highest
concentrations
Is It Safe To Eat Fish and Shellfish?
these four studies permit us to conclude that a number of toxic
contaminants are both present and available to marine organisms in
Boston Harbor.
Lobster
Several] studies have analyzed toxic contamination in tissue of lobster
(Homarus americanus) in and around Boston Harbor.
PCBs; The FDA action level for PCBs in marine animals is 2 ppm (wet
weight). Concentrations (parts per million wet weight) of PCBs in
muscle from lobster caught in Boston Harbor have been found to range
from as low as 0.03 to as high as 0.7. Animals examined in the EPA
1987 study of Quincy Bay had concentrations ranging from 0.20 to 0.27.
Although these levels are considerably below the action level,
differences in analytical methods mentioned previously must be kept in
mind. Studies that analyzed concentrations in all edible tissue,
including the hepatopancreas, or tomalley, found much higher levels of
PCBs. Values for these studies ranged from 0.1 to 61.8 ppm wet weight.
The marked difference in concentrations for different tissue has led to
the suggestion that consumers of lobster should avoid eating the
tomalley. In evaluating the risk of eating Quincy Bay fish and shellfish, —
the EPA study concluded that the risk of regular consumption of
tomalley from Quincy Bay lobster is high compared to that from other
types of eating and drinking activities and is comparable to that
associated with consumption advisories or fishery closures in upper New
York Harbor and Lake Michigan. Risk of consuming “typical” (about
10 meals per year) amounts of lobster muscle (without the tomalley)
was judged to be similar to that of other eating and drinking activities.
PAHs: Few data are available for PAHs in lobster tissue. The Quincy
Bay study, which did analyze PAH levels, found concentrations (parts
per million wet weight) up to 0.8 in lobster muscle and up to 4.2 in
tomalley. These concentrations are high compared to PAH levels found
in winter flounder tissue.
Metals: Of three studies that examined metal concentrations, al found
copper to be relatively high. However, the highest mean value (14.4
ppm wet weight) is still below the 430 ppm calculated as a target level
using the EPA Risk Reference Dose chronic values, and is comparable
to values found by the same study in Salem Harbor. This study,
4-11
Is It Safe To Eat Fish and Shellfish?
PCBs and pesti-
cides seem to be
decreasing in
shellfish
The risk of eating
diseased fish has
Transmission of
not been fully
evaluated
cancer from
diseased animals
consumption of
is unlikely, but
carcinogens is a
4-12
potential risk
conducted by investigators from the University of Massachusetts Boston
Harbor Campus, also found relatively high mean wet weight levels of
zine (17.6 ppm) and mercury (0.14 ppm). Once again, however, these
concentrations do not approach the target (2150 ppm for zinc) or action
(1 ppm for organomercury) levels for either metal.
Summary
For purposes of comparison, FDA action levels are available for PCBs,
DDT, dieldrin, and organomercury (see Table 4.1), For some other
contaminants, a screening assessment of impacts to human health can be
conducted using EPA’s health effects assessment methods. The
resulting target values have no regulatory significance and serve only to
indicate that contaminants at these concentrations should be monitored.
Major metal contaminants have been consistently below the action or
target levels. As already mentioned, direct comparison of data for
PCBs is probsematic. A number of the contaminants are found at
concentrations among the highest in the region and, in some cases, the
country. Only PCBs and the pesticides appear to have been decreasing
in harbor shellfish over the past 15 years. Nevertheless, it is reasonable
to conclude that from the standpoint of toxic contaminants, Boston
Harbor shellfish are relatively safe for human consumption.
Disease in Fish and Other Animals
The issue of disease and abnormal conditions such as fin rot in marine
animals is discussed in detail] in the next section, Are Fish and Other
Marine Resources Being Protected?, which deals with the health of the
living marine resources in Boston Harbor. The related question of
whether animals suffering from these conditions are safe for human
consumption is examined here.
The term safe daes not have a precise definition in this context. Most
activities have some risk associated with them, and the key is to decide
at what point the risk in a given situation is unacceptabje — that is,
outweighs the benefits. To date, no such evaluation has been made for
consumption of diseased fish. ,
One aspect of the question was addressed at a symposium on
Chemically Contaminated Aquatic Food Resources and Human Cancer
Risk held by the National Institute of Environmental Health Sciences.
Participants and members of the steering committee considered the
risks associated with consumption of fish or other seafood with tumors
and related conditions. These scientists unequivocally agreed that the
risk of becoming infected with cancer through transplantation of viable
Is It Safe To Eat Fish and She)lfish?
tumor cells, infection by a virus or bacteria, or more subtle mechanisms
involving transfer of the genetic material of the consumed tissues is too
remote to be worth considering. Any cancer risk, therefore, is confined
solely to the effects of ingesting carcinogens present in the animal at the
time of consumption. Thus the key question is whether animals with
neoplasms have elevated Jevels of cancer-causing chemicals in their
tissue. .
Results of various studies show that, although the edible flesh of some
tumor-bearing fish may contain residues of animal carcinogens such as
PAHs and PCBs, this is not the case for afl tumor-bearing fish. In fact,
residues measured in the edible tissue of tumor-bearing fish are usually
low. It is true, however, that fish with elevated concentrations of PCBs
and PAHs have been found in Boston Harbor, and the implications of
this issue are discussed above.
REPORT CARD Now 1992 1995 2000 2005
IS IT SAFE TO EAT FISH AND SHELLFISH?
Shellfish: Pathogens D- D c- C- B-
Fish: Organic contamination c- Cc c C+ B-
Fish: Metal contamination B- B- B- B Bt
4-13
5. ARE FISH AND OTHER MARINE RESOURCES
‘BEING PROTECTED?
The well-being of
marine animals is
related to
conditions in the
water and
sediments
The harbor usually
meets standards
for toxic materials;
dissolved oxygen
and pathogens are
sometimes outside
established limits
Concern about whether marine resources are being protected from
pollution is not the same as concern about whether we will be able to
safely eat fish and shellfish. In this section, we are interested in the
well-being of the resources themselves. We focus on fish and benthic
animals as groups that contain commercially valuable species and have
been subject to enough investigation to make useful data available. A
third factor influencing the choice is the likelihood that members of
these groups will show effects that can be related to contamination of
the environment. The health of fish and benthic animals is affected by
conditions in the water and in the sediments.
What are the priority pollutants?
As defined by the Federal Clean Water Act, priority pollutants are
selected compounds considered to be the most persistent, prevalent,
and toxic. In marine waters, the following priority polJutants are closely
regulated:
Aldrin Dieldrin PCB
Arsenic Endosulfan Pentachloro-
Cadmium Endrin phenol
Chlordane Heptachlor Selenium
Chromium Lindane Silver
Copper Lead Toxaphene
Cyanide Mercury Zinc
DDT PAH
One way to judge the condition of the water in Boston Harbor is by
comparing observed conditions with standards established by agencies
that regulate the environment. In general, concentrations of the priority
pollutants in the harbor are rarely greater than established standards,
dissolved oxygen concentrations in the Inner Harbor are sometimes
Jower than the minimum standard, and concentrations of fecal coliforms
and enterococci often do not meet established standards.
5-1
Are Fish and Other Marine Resources Being Protected?
The State has set a
goal that Boston
Harbor be suitable
for swimming and
fishing (in some
areas, harvested
shellfish may
require depuration)
Studies show that
_ Boston Harbor
usually meets
Standards that
support the State
goals
Pathogens and
dissolved oxygen
are sometimes
outside set limits
Metal
concentrations are
generally below
established
guidelines
Water
Water Quality Criteria
The Federal Clean Water Act requires EPA to develop water quality
criteria for marine waters. These criteria are then used by the States to
set water quality standards. designating different classes of waters, based
on goals for the use of those waters. Marine and coastal waters are
separated into classes, each with a set of minimum criteria as goals for
water quality. Waters in Boston Harbor are rated as either SA or SB,
as shown in Figure 5.1. Class SA waters are designated for the
protection and propagation of fish, other aquatic life, and wildlife. They
are intended to be suitable for primary and secondary contact
recreation, and for shellfish harvesting without depuration in approved
areas, Class SB waters have a similar designation, except that any
shellfish harvested must undergo depuration.
One program that monitors water quality in the harbor is being
conducted by the New England Aquarium. Measurements of water
temperature, salinity, pH, dissolved oxygen concentration, suspended
solids, and turbidity are made monthly between March and November.
Data are available for measurements between April 1987 and July 1989.
Results from 10 stations in the harbor and one just outside, in Broad
Sound, show that, overall, few water quality criteria are being violated in
Boston Harbor. The main exceptions are criteria for pathogens and
dissolved oxygen in the Inner Harbor, Pathogens are discussed in the
previous two sections, because they affect human users of the harbor
rather than its marine resources.
For dissolved oxygen, standards were not met on 10 of 22 sampling
dates. Most of these cases were in the Inner Harbor, especially in Fort
Point Channel. The minimum oxygen concentration seen, 4.07 mg of
oxygen per liter of seawater, could cause physiological stress in marine
animals such as fish, but is not low enough to kill a healthy animal.
These conclusions are supported by results of other studies conducted
by the Massachusetts Audubon Society and the Massachusetts Division
of Water Pollution Control.
Metal Contamination
Massachusetts has not yet adopted criteria for the maximum
concentrations of metals allowed in marine waters; however, some
Federal guidance is available. EPA has established Criteria Maximum
Concentrations, which are concentrations of contaminants considered
safe. For the most part, metal concentrations in the harbor are below
these Jevels.
Are Fish and Other Marine Resources Being Protected?
Nohant
Bay
Broad Sound
Southeast
Harbor
Hingham
$A = Swimming, Fishing and Shellfishing
$B = Swimming, Fishing and Restricted Shelifishing
Figure 5.1. Massachusetts Surface Water Quality Standards set goals for Quincy and
- Hingham Bays of Class SA, the highest quality with the strictest standards. All
other harbor areas are Class SB.
5-3
Are Fish and Other Marine Resources Being Protected?
Studies suggest.
that metal
concentrations in
the harbor are
decreasing
Contaminants
accumulated in
sediments are an
environmental
problem, but no
5-4
regulatory
standards now
exist
Over the years, data have been collected in a number of studies on
concentrations of metals in Boston Harbor. To try to establish what the
harbor’s conditions are now, and how they are changing, MWRA has
examined data from six studies by different groups. To simplify the
comparisons, two representative metals were examined in detail: copper
because of its well-known toxicity and zinc because it is found in
relatively high concentrations in the harbor. One further simplification
was used. Metals in seawater can be dissolved in the aqueous phase or
be adsorbed to particles, but most of the studies found that the
particulate concentrations of zinc and copper are about 30% of the
dissolved amount. Therefore, only dissolved metals were considered.
Comparison of data from the six studies suggests that concentrations of
metals dissolved in Boston Harbor water are decreasing (Figure 5.2).
This agrees with the observation, discussed in Section 2, that the amount
of metals in sewage entering the MWRA system has declined about
75% over the past 8 years. Additional work is needed to study the
remobilization of metals from the sediment to the water column, but
indications are that levels of metals in harbor water will respond quickly
once the sludge discharge is stopped and the effluent outfall is moved
to Massachusetts Bay.
Sediments
The levels of contaminants in the water and biota have been of concern
for many years. It has also been recognized for some time that
contaminants accumulate in sediments, but most people considered this
process a means of removing toxic contaminants and keeping them “in
place.” It has now become clear that toxic contaminants in sediments
also pose a threat to aquatic and human health and that these in-place
contaminants can be transported on sediment particles to other areas
and released to the overlying water column. Therefore, the levels of
contaminants in sediments are as important as those in water.
Unfortunately, it is more difficult to assess the condition of sediments
than the condition of water because no numerical standards have been
established for sediment contaminants. Although EPA and several
states are currently developing quality criteria for sediment, the scientific
basis for determining what levels of contaminants constitute a problem
is not well developed, and several technical difficulties must be
overcome before any standards can be implemented.
Current methods used to assess the condition of sediments in Boston
Harbor are (1) description of the geographic extent of contamination,
(2) comparison of contaminant concentrations in Boston Harbor with
other areas, (3) direct observation of the fish and other organisms
Are Fish and Other Marine Resources Being Protected?
72
a3 "67 "88 ‘BS
Inner Harbor Cu (ug/L) 2n (ug/L)
10
8 (40
6 30
Tel] 4 (__] Cu i 2n 20
Z) ‘a7 ‘88 ‘89 ’ 2 10
° '72 "83 "87 '88 "BS °
NW Harbor Year
Central Harbor
Figure 5.2. Concentrations of copper and zinc in Boston Harbor water seem to have declined
between 1972 and 1988. Data from Gilbert et al. (1972), Wallace et al. (1988),
MWRA (1988), Sunda and Huntsman (1989a,b).
5-5
Are Fish and Other Marine Resources Being Protected?
Data on present
conditions will
help assess future
changes
Improvements in
sediment
conditions will
take place slowly
5-6
Why are we concemed about contaminants in sediments?
Many organisms have direct contact with sediments, so contaminants in
sediment may have as much of an impact on their health and survival
as those in the water.
Many contaminants are not very soluble in water, but readily bind to
sediment particles. For example, the levels of PCBs are usually a
million times greater in sediments than they are in the overlying water.
Low-level discharge of a contaminant may meet State and Federal
water quality standards, but long-term accumulation in sediments can
Tesult in high levels. In addition, sediment-bound contaminants will
remain for long periods of time, even after the sources of
contamination are shut off. This sink can later serve as a source, as
contaminants are released from the sediments and sediment particles
are transported to other areas.
J
residing in or near the sediment, and (4) determination of any trends in
the levels or geographical extent of contaminants (are the problems
getting better or worse?).
The contamination of Boston Harbor began a hundred years ago when
Gomestic and industrial waste was first discharged to harbor waters.
Scientific studies, on the other hand, have been conducted for only
about 20 years, and any study can provide a picture of contamination
levels and locations at only 4 particular point in time. Nevertheless,
data gathered over two decades have helped us reach some conclusions
about present conditions. We can now use this baseline of information
to monitor changes and assess the response of the harbor to mitigation
measures.
The harbor will not recover overnight. Not all sources of contamination
are being eliminated, and contaminants built up over the years are
tightly bound by sediments. Processes that result in the removal of the
accumulated contamination are slow. These processes include gradual
Telease of contaminants to the overlying water, followed by dispersal, or
burial by the cleaner sediment that will be deposited in the future. We
should, however, begin to see a stabilization of conditions and eventual
improvement.
Our most reliable
- information is on
the amount of
contamination for
particular times
and places
Data must be
interpreted
carefully: a few
atypical areas can
bias results
Most
contaminants are
highest in the
Inner Harbor and
decrease in the
Outer Harbor from
north to south; hot
spots are found in
areas where
sediments
accumulate
Are Fish and Other Marine Resources Being Protected?
What Is the Extent of Sediment Contamination in Boston Harbor?
Several scientific studies have identified the sources and estimated the
amounts of contaminants entering Boston Harbor each year. Results
from these studies clearly indicate that sewage and CSO discharges are
the primary sources of most contaminants and that atmospheric
deposition, direct river inflow, and direct land runoff are less important,
but stilf significant. However, the fraction that each source contributes
to the total input cannot be estimated very accurately. We also do not
know for sure how long the contaminants remain in the harbor or where
they eventually end up. What we do know is the concentration of
contaminants in many locations within the harbor at a particular time.
The extent of sediment contamination is often expressed as the mean
(average) level of a contaminant in a particular area. This assumes that
the mean value represents a value typical of the area. In reality, the
distribution of contaminants is often uneven: there will be some hot
spots and many cleaner areas. For example, a study of organic
contaminants in the sediments at five locations in Boston Harbor
yielded a mean PAH level of 180 ppm, but only one value exceeded 6.5
ppm. A hot spot on Deer Island Flats had a concentration of 880 ppm
and caused the high mean value. If that hot spot is excluded, the mean
value becomes only 4.4 ppm. Furthermore, the median value was only 6
ppm, and is much more representative of the typical PAH level in
Boston Harbor. The median value in a set of numbers is the value in
the middle; 50% of the values are higher and 50% are lower. We can
obtain a very different picture of the sediment quality, depending on the
distribution of contamination (more or less homogeneous and with or
without hot spots) and how we present the data (mean or median). The
information presented below includes the mean values with and without
hot spots to illustrate this difference.
Levels of contaminants in the sediments of the four regions in Boston
Harbor have been reported by several investigators and these data are
summarized in Table 5.1. Although it is often difficult (and sometimes
inappropriate) to compare data from different scientific studies when
different procedures were used for sample collection and analysis, the
methods used to obtain these data are considered sufficiently
comparable (within a factor of 2 or 3) to develop a general picture of
Boston Harbor. Most contaminant levels are highest in the Inner
Harbor, decrease stightly in the northwest harbor, decrease stil] further
in the central harbor, and are lowest in the southeast harbor. This
pattern is particularly true for PCBs and most metals (copper, lead,
cadmium, nickel, zinc, chromium, mercury, and arsenic). Silver and the
pesticide DDT are more evenly distributed throughout the harbor.
PAHs have an uneven distribution, with locally elevated concentrations,
or hot spots, in the Inner Harbor, on Deer Island Flats, and off Moon
5-7
Are Fish and Other Marine Resources Being Protected?
Table 5.1. Mean contaminant concentrations (ppm dry weight) in the sediments of Boston
Harbor.
Contaminant Region Reference
: Value™
Overall Inner Northwest Central Southeast
Harbor Harbor Harbor Harbor Harbor
PAH? 7.9 (84) 20(173) 4.4 (154) 4.4(8) 2.2 35
PCB 0.56 0.75 0.67 0.37 0.17 0.4
DDT 0.035 ND 0.050 0.029 ~—0.025 0.35
Arsenic 14.2 20.3 . 9.7 10.5 15 85
Cadmium 2.75 432 2.91 1.48 1,28 9
Chromium 133 166 145 107 86 145
Copper 105 150 105 84 57 390
Lead 131 192 127 83 101 110
Mercury 1,33 1.61 1.57 0.98 0.71 13
Nickel 34 52 27 33 24 50
Silver 3.12 3.32 3.40 3.21 1.22 2.2
Zinc 219 348 184 151 134° 270
Data are from Battelle (1990), Boehm et al. (1984), COE (1981), DEQE (1986,
1987), Gilbert (1972), Isaac and Delaney (1972), Iwanowicz et al. (1973), Shiaris
and Jambard-Sweet (1986), U.S. EPA (1987), White (1972). ND = no data.
*Effects level (Effects Range — Median) calculated by NOAA (Long and Morgan,
1990) from collated data (see text).
’Number in parentheses includes all “hot spots.”
‘Includes DDT and its metabolites. The data set is very small.
5-8
Boston Harbor
sediments are
generally 2 to 5
times more
contaminated than
those typical of
New England
coastal areas
Geographical
comparisons must
be kept in proper
perspective
NOAA NS&T
daia are useful for
general
comparisons
Are Fish and Other Marine Resources Being Protected?
Island. Mean PAH levels were calculated both with and without the hot
spots, yielding about a factor of 10 difference. The geographic
distribution of five of these contaminants is shown in Figure 5.3, along
with National Status and Trends (NS&T) data from the remaining New
England sites and for the five cleanest NS&T sites in the nation, There
are clear differences in the levels of contaminants in different regions of
Boston Harbor and very dramatic differences when one considers the
hot spots that exist. These hot spots are usually a result of high rates of
sediment accumulation —areas where the transport of contaminated
suspended particles tends to focus. Thus, small areas within the harbor
have become much more contaminated than the overall harbor.
It is clear from the data in Table 5.1 and Figure 5.3 that all of these
contaminant levels are significantly above the most pristine sites in the
nation. Contaminant levels are elevated by factors from 3 (for arsenic)
to nearly 1000 (for PAH), and are even greater at the hot spots.
However, the levels of contaminants in Boston Harbor sediments are
only 2 to 5 times higher than those typical of coastal New England
sediments. Although there are no State and Federal guidelines for
sediments, NOAA has collated results of studies for which data on both
sediment concentrations and biological effects are available. This
information was used to develop effects levels at the midrange of
reported values associated with biological effects. On average, PCBs,
lead, mercury, and silver concentrations in Boston Harbor exceed the
NOAA effects levels. PAHs, chromium, and zine can exceed those
levels in contaminated hot spots.
How Do Boston Harbor Sediments Compare to Other Urban Areas?
The contamination of Boston Harbor sediments with toxic chemicals
received immense public and political attention in the last few years.
Comparison of Boston Harbor to other urban coastal regions resulted in
the label “the dirtiest harbor in the nation.” Comparisons such as these
are easily misinterpreted and often inappropriate — comparing apples to
oranges. Nevertheless, general comparisons are useful for putting the
levels of contaminants in perspective and selecting the areas in greatest
need of attention to mitigate environmental degradation.
The data most commonly used to compare harbor contamination are
from the NS&T Program. This is a large data set that does not include
a lot of hot spots, so the mean and median values are similar for most
sites, and all of the sampling and analytical methods are identical. The
mean and range of PAH levels in the sediments of several urban coastal
areas measured over the past 4 years is shown in Figure 5.4. Although
the mean PAH level in Boston Harbor is elevated above background
(Table $.1 and Figure 5.3), it is similar to other urban areas on
5-9
Are Fish and Other Marine Resources Being Protected?
Overall Harbor New Eaglond Average Pristine Site
bors
=
Cadmium
87 [-) PAH Mill Pcs
Mercury £r2] Silver
NW Harbor
J southeast
Harbor
‘SE Harbor
rirt
Figure 53. The distribution of toxic chemicals in Boston Harbor sediments illustrates the
geographic pattern of contamination (excluding hot spots).
5-10
Are Fish and Other Marine Resources Being Protected?
Level of PAH in Sediment (ppm)
35
BO feccceeeeeceeeeteseeesteeeeeeetesteeeentessneieaa|eeeeessnaneeeenees
DB deecccceeee tees eetet esa eeeteeeeeeeeesaaaaaaeeesed [oeeeeeetesaaaaaess
DO diicccectcceeeeeeee etree eteeeteeteuasaaeeneeeeee [occeeeersgaaeeees ~
15 fecceeeeee cess ee eeetee se eseeeeeeeeeeeeana serene [ocaeneeeeesaaaeees
AO fececcceeeee seen teeeeterecstenteserteeteeeeeteeefeseeesseeseeeenaea
Boston Buzzards Long Island New York Chesapeake
Harbor Bay Sound Bight Bay
Figure 5.4. Comparison of the levels of PAHs in sediments from several locations on the east
coast. The vertical lines represent the range of values and the squares represent
the mean, All data are from the NS&T Program.
5-11
Are Fish and Other Marine Resources Being Protected?
Some research
indicates that
concentrations of
metals are
decreasing
The relation
between pollution
and abnormal
conditions in fish
has been studied
in winter flounder
5-12
the east coast. The same type of comparison can be found for PCBs,
pesticides, and metals. Thus Boston Harbor ranks among the highest in
contamination, but it has a lot of company.
Are the Problems in Boston Harbor Getting Better or Worse?
We do not have data from the NS&T program over a long enough time
period to determine with confidence whether contaminant levels in
Boston Harbor sediments are increasing or decreasing. Only now are
we beginning to establish the baseline from which future measurements
can be used to determine trends in sediment contamination.
However, some scientists have suggested that the levels of some
contaminants, primarily metals, may be decreasing already. These
claims are based on data from sediment cores where contaminant levels
were measured at depth intervals down into the sediment, rather than
just at the sediment surface (all of the data presented above), The core
measurements allow one to estimate thé historical accumulation of
contaminants by measuring the concentration of contaminants at a
particular depth in the sediment and using lead-210 dating to determine
when those contaminants reached the sediment. One study indicated
that there has been a significant reduction in the input of copper and
cadmium (and possibly other meta}s) to the sediments of Boston
Harbor in recent years. This could be due to the reduced metal content
in the sewage discharges mentioned above. The rates of reductions in
input suggest it could take more than 100 years to lower the meta) input
by 50%. However, this assumes that no further mitigation will occur,
With the removal of sewage sludge from the discharge (in 1991), the
extension of the outfall 15 km into Massachusetts Bay, and the
remediation of most CSOs, the time required to see a noticeable
improvement should be much shorter. ;
Fish
A number of diseases and conditions have been observed in fish and
linked, at least circumstantially, to pollution. Conditions can be broadly
categorized as external abnormalities, including fin erosion, skin and gill
lesions, parasites, skeletal abnormalities, and abnormal pigmentation;
and internal abnormalities, involving lesions such as tumors.
Although several recreationally and commercially important fish species
are exposed to contaminants in Boston Harbor, investigations of disease
Ave Fish and Other Marine Resources Being Protected?
Glossary of disease-related terms
Carcinogen: A cancer-producing substance.
Carcinoma: New and abnormal tissue growth that is malignant.
Fin rot: A condition characterized by the progressive death and erosion of the tissue of the fins
in fish; also known as fin erosion. .
Hepatic: Pertaining to the liver.
Lesion: An abnormal change in the structure of tissue, caused by disease or injury.
Lymphocytosis: A condition-characterized by an excess of normal lymphocytes in the blood;
lymphocytes are a type of white biood cell.
Neoplasm: New and abnormal tissue growth that may be either malignant or benign; a tumor.
Preneoplastic: An abnormal change in the structure of a tissue prior to the formation of a
tumor, ~
Vacuolated cells: Cells whose protoplasm contains spaces or cavities; also known as
preneoplastic lesions.
and abnormalities in harbor fish have concentrated on winter flounder
(Pseudopleuronectes americanus). These studies have focused on winter
flounder for the same reasons discussed in Section 4; that is, because
they are an abundant and valuable species and because their behavior
makes them susceptible to the effects of contamination in the
environment. ‘
External Abnormalities
Fin rotis A variety of external abnormalities occur in fish. Fin rot, also known as
frequently observed fin erosion, is the condition recognized most frequently; it attacks the
in fish dorsal and pectoral fins. Pathologists disagree about the cause of this
condition. No conclusive evidence exists to confirm that fin rot is
causéd by bacteria, vitamin deficiencies, or pollution.
§
Authors of a NOAA special report suggested that a fin rot prevalence of
greater than 25% is alarming because (1) fin rot seen in 25% of an
individual fish stock is rare and indicates the likelihood of other
pollutant-induced effects (e.g. lesions) that may or may not have been
5-13
Are Fish and Other Marine Resources Being Protected?
Other kinds of external abnormalities in fish
The presence in winter flounder of the other diseases discussed below is not reported in the
literature as frequently as fin rot and liver lesions. There is no conclusive evidence to suggest
that the occurrence of these diseases in fish is caused by contaminants in the marine
environment. Some of these conditions were observed during Fish Day, a monitoring effort
sponsored by the New England Aquarium.
Epidermal Lesions
Epidermal (skin) lesions include skin tumors (benign or malignant), viral-induced lesions, and
other types of lesions. Epidermal tesions may result from direct exposure to contaminated
sediments. Topical application of contaminated sediments to the brown bullhead (Icta}urus
nebulosus), under laboratory conditions, resulted in the production of epidermal lesions. Six of
914 winter flounder collected during a series of trawl surveys off Boston from 1979 to 1983 and
examined by the Division of Marine Fisheries had skin lesions.
Parasites
Pepper spot disease was reported in 26% (20 of 79) of fish examined for Fish Day. Pepper spot
disease is caused by encysted trematodes (parasitic flatworms). It js diagnosed most often in
fish collected from inshore areas. Trematodiasis of the gills was observed in 90% of winter
flounder collected from Quincy Bay.
Gill Neoplasms/Lesions
Gill neoplasms, a type of tumor, were diagnosed in winter flounder collected during the
National Status and Trends Program. Gilt lesions were detected in winter flounder collected in
Quincy Bay.
Skeletal Abnormalities
Skeletal abnormalities were diagnosed in 4 of 914 winter flounder examined by the Department
of Marine Fisheries. Fish Day results indicated that 39% (31 of 79) of fish examined had bent
fin rays. The majority (58%) of these fish were caught on Deer Island Flats. Also, 5 5% (6 of
120) of fish examined for Fish Day were dwarfs.
Abnormal! Pigmentation
Color anomalies were diagnosed in 2 of 914 winter flounder examined by the Division of
Marine Fisheries. Ambicoloration was diagnosed in 28% (22 of 79) of the fish examined for
Fish Day. Most of the fish (63%) with ambicoloration were caught on Deer Island Flats.
measured; and (2) the portion of the fish stock with fin rot may cause
increased mortality through fishing (the fish is unable to avoid the net
because the fin is damaged), and predation (the strong prey on the
weak), and thus may have economic and aesthetic consequences for
both commercial and recreational fishing.
5-14
Studies disagree
about the
incidence of fin rot
in harbor flounder
Circumstantial
evidence links fin
rot to
contamination
Lesions, especially
of the liver, are the
most common
internal
abnormality seen
in fish
Studies suggest
that some internal
abnormalities may
be related to
contamination
Arse Fish and Other Marine Resources Being Protected?
Boston Harbor Studies: Some studies found the prevalence of fin rot to
be more than 25%—what the NOAA repart called the warming Sevel—in,
Boston Harbor winter flounder. However,-at least one study found a
similar result in coastal areas (<27 m in depth) of Cape Cod and
Massachusetts Bays. Fin rot was found to be prevalent in winter
flounder collected for the Metropolitan District Commission near Deer
Island during the summers of 1978 and 1979. Forty-two percent of all
flounder collected during the 1979 survey exhibited some degree of fin
erosion. During the Fish Day exercise in May 1989, only 2.5 % (2 of
79) of the fish were observed with active fin rot. Sixteen percent (13 of
79 fish) examined had fin rot that was in the process of healing.
Evidence for an Environmental Connection: Although the etiology of fin
rot has not been conclusively determined, it has been generally
associated with coastal environments degraded by pollutants and
directly associated with the discharge of municipal wastewater. Fin rot
was induced in spot (Leiostomus xanthurus) and Dover sole when each
species was exposed to contaminated sediments. A study of disease in
commercially valuable fish stocks in the Northwest Atlantic revealed that
fin rot and other abnormal conditions such as lymphocystis and skeletal
abnormalities were more numerous in flatfish than in roundfish such as
hake. In addition, several of these conditions reached maximum n levels
in fish stocks located near major cities.
Internal Abnormalities
Internal abnormalities may be diagnosed using histopathologic
techniques that study the microscopic structure of tissue.
Histopathologic studies of fish most often involve the examination of
lesions— abnormal changes in the structure of tissue —in the liver, skin,
and gill. Lesions involving the liver, known as hepatic lesions, are very
prevalent in fish residing in contaminated marine environments. |
The liver is susceptible to tissue damage because it metabolizes toxins
taken up by fish inhabiting contaminated environments. The
metabolism of the toxins may result in the formation of lesions.
Hepatic lesions have been compared microscopically to several types of
liver cancer found in warm-blooded animals, including man.
Boston Harbor Studies: Relatively few studies have been conducted on
the occurrence of histopathological conditions in finfish from Boston
Harbor, but those that have been done have created considerable
interest. Attention was originally focused on Boston Harbor fish
histopathology by a study from the National Marine Fisheries Service
5-15
Are Fish and Other Marine Resources Being Protected?
Data from other
5-16
areas suggest
a relation to
contamination
that described-a high prevalence of carcinomas in winter flounder from
the harbor. Winter flounder collected from the southern shore of Deer
Island had a number of visible hepatic lesions that might be indicative
of the fish livers’ efforts to metabolize toxic substances. The fish also
had a large number of unusual vacuolated cells, and 10% of the animals
examined had preneoplastic or neoplastic lesions.
Another author examined winter flounder collected near Deer Island
and from a reference site off Plymouth Beach during the summers of
1981 and 1982, The livers in these Deer Island fish also had a
disproportionately large number of the unusual vacuolated cells. More
intensive study revealed that these abnormal cells were often found in
large nodules of several hundred cells and that the same nodules often
contained clumps of neoplastic cells.
The Benthic Surveillance Project of the NOAA NS&T Program
reported on the results of histopathological observations of winter
flounder collected from Boston Harbor and other northeastern sites
during 1984, 1985, and 1986. Seventy-five percent of the tumors found
in the flounder were in fish from the Boston Harbor area. Of winter
flounder collected in Quincy Bay during 1987, 29 of 100 had neoplastic
growths. Most of the neoplasms were tumors of the liver and bile ducts.
A characteristic of most of these studies was that larger/older fish
exhibited more severe lesions than smaller/younger fish. This may be
due to a longer period of exposure for older fish indigenous to a
contaminated area.
Links between Disease and a Contaminated Environment: Comparisons
can be made between the results of histopathological studies of Boston
Harbor winter flounder and Puget Sound English sole (Parophirys
vetulus), Puget Sound is an estuary that is contaminated, like Boston
Harbor; English sole is a flatfish, like winter flounder. The results of
studies conducted on Puget Sound English sole to determine the cause
of hepatic carcinoma and other hepatic fesions revealed that (1) the
number of hepatic lesions (nonspecific) was significantly correlated
(positive) with leveJs of PAHs and metals in sediments, and (2) the
number of neoplasms had a significant positive correlation only to PAH
concentrations in the sediments, Neither the number of hepatic lesions
nor the number of neoplasms was significantly correlated with
chlorinated hydrocarbons such as PCBs. The results indicate that the
presence of chemical agents in the sediments can be correlated with the
prevalence of hepatic lesions. This type of study has yet to be done on
Boston Harbor winter flounder.
Are Fish and Other Marine Resources Being Protected?
Fish Day at the New England Aquarium
May 13, 1989, was Fish Day in Boston Harbor. In an unprecedented enterprise organized by
the New England Aquarium and the Massachusetts Audubon Society, 100 fishermen turned out
to catch fish for study by scientists from 12 organizations. The purpose of the effort was to
assess the health of the fish population and provide information useful to those responsible for
decisions about the harbor.
The fishermen caught more than 200 winter flounder at 10 locations. Participating scientists
performed 13 separate studies, looking at everything from stomach contents (to provide
information about diet) to enzyme analysis (to evaluate exposure to toxic chemicals).
The study produced valuable background information such as fish size and age and gave
scientists a chance to test certain diagnostic techniques.
Some conditions, including liver lesions and neoplasia, were puzzlingly less prevalent than
expected among the catch. On the other hand, more than a third of the fish, especially those
from Deer Island, had bent fin rays. Many had other abnormalities that suggested they were
suffering from the effects of a contaminated environment. Clearly, the results of Fish Day-must
be interpreted with caution, and more studies wil! be needed to evaluate trends with confidence.
The fishermen near Deer Island caught more fish than their counterparts elsewhere in the
harbor. Half the fish from Deer Island Flats had stomachs filled with a marine worm whose
presence is frequently associated with sewage pollution. It seems that even if Deer Island fish
are unhealthy, they make extensive use of the large food reserves found there.
In Boston Harbor, At present, the co-occurrence of neoplastic lesions in Boston Harbor
hepatic lesions can _ winter flounder and sediments containing high concentrations of PAHs
be circumstantially and PCBs is circumstantial and inconclusive. Inferences that specific
linked to chemical agents cause hepatic neoplastic lesions found in Boston
environmental Harbor winter flounder are unsubstantiated by experimental data.
contamination However, the high prevalence of hepatic lesions can be linked, in
general, to poor environmental quality. This link has been substantiated
by a panel of the National Institute of Environmental Health, which
reported a definite correlation between the high prevalence of hepatic
and epidermal tumors and the presence of carcinogens in the habitats of
the fish. Further circumstantial evidence is provided by the fact that
morphological changes observed in the livers of Boston Harbor winter
flounder are comparable to changes experimentally induced with
carcinogens in rodents.
5-17
Are Fish and Other Marine Resources Being Protected?
The effects of
disease on fish are.
not well known;
flounder appear to
live successfully in
contaminated
areas
Bottom-living
animals are also
studied to gain
information about
the environment
In the late 1970s
and early 1980s,
parts of the harbor
were found to
show signs of
environmental
stress
CSOs have been
shown to adversely
affect nearby
benthic
communities
5-18
Effects on Population: The consequences of hepatic carcinomas
(malignant hepatic lesions) on winter flounder populations are not
known. Most winter flounder containing hepatic carcinomas appear to
be as robust as fish without cancers. In a summary report, the National
Status and Trends Program reported that, because winter flounder
appear to thrive (e.g., grow and reproduce) in contaminated
environments such as Boston Harbor, winter flounder may be an
inappropriate indicator species (the indicator would be the formation of
tumors) to be used as an early warning of environments that are
beginning to degrade as a result of increased presence of contaminants.
Benthic Animals
Benthic animals live in or on sediments at the bottom of a body of
water. Common benthic marine animals include polychaetes (worms);
clams, mussels, and other bivalves; starfish, sea urchins, and other
echinoderms; amphipods (a type of crustacean related to shrimp), crab,
and lobster; and other sessile, creeping, or burrowing forms. Some
members of the benthic community are important for their commercia!
value (e.g., lobster, crab, and clam); others serve as food for bottom-
feeding fish and lobster. In addition, benthic communities have
traditionally been monitored as an indicator of environmental health.
Because most of these animals live a sedentary existence, they are
susceptible to contamination from a localized source and show its
effects by changes in the structure of their communities. These changes .
are expressed as variations in the kinds of animals found at a particular
site (composition), the number of different species (diversity), and the
total number of individuals (abundance or density).
In support of an application for a waiver from the requirement to
institute secondary treatment for effluent discharged to Boston Harbor,
benthic samples were collected during the summers of 1978, 1979, and
1982. In general, the results suggest that the environment is stressed in
the middle of the harbor and in the Inner Harbor, and on the mud flats
west of Deer Island where the water is shallow and the currents weak.
Stations in the rest of the Outer Harbor are more similar to Stations in
Massachusetts Bay than to stations in the Inner Harbor and the north-
west Outer Harbor, indicating that they are less affected by pollution.
Intensive studies near one CSO indicated that these overflows have
severe, localized effects on the adjacent benthic communities. A 1987
investigation of the benthos near the Fox Point CSO demonstrated that
both diversity and abundance were significantly lower at the mouth of
the discharge than at a nearby reference site. Similarly, other studies
have found that the abundance and diversity of the benthos decline as
Fox Point is approached.
Recent research
suggests that
benthic
communities near
discharges are
affected by
contamination, but
other areas of the
harbor are
relatively
unimpacted
Ase Fish and Other Marine Resources Being Protected?
A recent study, performed using sediment profile imaging, identified
general areas showing environmental stress. In this technique, a camera
designed like an inverted periscope photographs a cross section of the
top 15 to 20 cm of sediment, and the photographs are analyzed in
several ways. With the exception of one replicate from a station on
Deer Island Flats, all sites showed evidence of benthic fauna. However,
results showed that the fauna on Deer Island Flats, in Winthrop
Channel, and in the approach channels to East Boston and Cambridge
was mostly restricted to smail organisms that inhabit a thin layer of
oxygenated sediment that overlies a thick layer devoid of oxygen.
Large, deep-dwelling organisms that introduce oxygen into the
sediments by their burrowing and feeding activities were apparently
missing from these areas. Such large organisms are among the most
sensitive to large amounts of organic matter, which suggests that the
locations mentioned are being affected by additions of sewage to the
bottom habitat.
A combination of other observations, including biological mixing,
dissolved oxygen, and size of particles making up the bottom sediments,
also pointed to Deer Island Flats, Winthrop Channel, the entrance to
the Inner Harbor, an area immediately north of Spectacle Island, and
most of the Inner Harbor and Dorchester Bay as impacted sites. Most
sites in Quincy, Hingham, and Hull Bays were less stressed. In general,
conditions improved with distance offshore toward Massachusetts Bay.
In summary, these results all suggest that the benthos in some areas of
the harbor (particularly those close to discharges) shows adverse effects
due to contamination, but that other areas (particularly the Outer
Harbor) are relatively heaJthy. This reinforces the general picture that
conditions in the harbor cannot be summed up as uniformly bad. It
also suggests that monitoring of benthic populations in the more
affected areas offers a means to detect whether there are improvements
over time.
5-19
Are Fish and Other Marine Resources Being Protected?
REPORT CARD Now 1992 1995 2000 2005
ARE MARINE RESOURCES PROTECTED?
Sediment contamination D- D D Cc C-
Water quality: Oxygen c- Cc B B B
Water quality: Toxic contamination B- B B+ B+ A-
Fish disease D- D D+ C- C+
Benthic communities D- D D [on C-
5-20
6. HOW DOES THE HARBOR RATE
AESTHETICALLY?
Sights and smells
related to sewage
interfere with
enjoyment of the
harbor
MWRA has halted
the daily discharge
of £0,000 gal
of scum
Sludge discharge
will cease in 199];
effluent discharge
will be moved
offshore in 1995
Water clarity
should improve
Aesthetics are an important part of the cleanup effort. To some people,
a harbor that looks and smells clean is almost as important as one that
is free of chemicals and microorganisms that are a threat to health.
Unpleasant sights and odors keep people away from the harbor and
interfere with its use as a recreational resource. The main
considerations in the aesthetic rehabilitation of Boston Harbor are
scum, sludge, and effluent from treatment plants, turbidity, algal
blooms, and floatable debris.
Scum
MWRA has already taken a major step by implementing a new system
of handling scum, the floating material generated by the wastewater
treatment process at a rate of 10,000 gai per day. In 1989, MWRA
eliminated scum discharges to the harbor. Under the new system,
grease, fats, most tampon applicators, and other floating pollutants are
removed from wastewater. The dewatered and chemically fixated scum
is now being disposed in a landfill, but by the end of 1991 it will be
processed along with the sJudge.
Effluent and Sludge
Plumes of waste material flowing into the harbor from treatment plant
discharges wili be a thing of the past within a few years. Streams of
malodorous and unsightly sludge will be eliminated in 1991 when sludge
is treated at land-based facilities instead of being discharged into the
harbor. As for effluent, by 1995 the new outfall will be completed,
permitting discharge farther offshore in Massachusetts Bay.
Turbidity
Cessation of particle-laden sludge and effluent discharges will also have
a positive effect on turbidity. Water transparency is expected to
improve substantially except when river flow is heavy or if the altered
conditions in the harbor increase blooms of algae. Concentrations of
suspended solids are about 100 times higher near the sludge outfall and
some CSOs than they are in other parts of the harbor.
6-1
How Does the Harbor Rate Aesthetically?
Algal blooms
could become
more frequent
Dangerous and
unsightly floatable
debris has many
SOUFCES
Algal Blooms
Blooms of the minute algal species that make up the phytoplankton
could become more of a problem than in the past. Such blooms can
discolor the water, produce unpleasant odors when their cells decay,
and potentially result in fish kills that cause further undesirable sights
and smells. Two factors that influence such blooms are concentrations
of nutrients, especially nitrogen and phosphorus, and available light.
The New England Aquarium describes Boston Harbor’s current nutrient
concentrations as high, but within the ranges observed for temperate
estuaries. Of the stations sampled by the Aquarium, nutrient
concentrations were highest in the Inner Harbor and lowest at the
southern stations in Hingham Bay, Weymouth Fore River, and Quincy
Bay. Both nutrients and available light are expected to change as the
harbor cleanup progresses. When sludge and effluent are no longer put
into the harbor, available light will increase and nutrient levels are
predicted to decrease.
Floatable Debris
The problem of marine debris floating in coastal waters and washing up
on beaches and shorelines has attracted considerable public attention in
recent years. Floating marine debris can be made up of an assortment
of waste materials. Plastic articles are one of the biggest categories of
floatable debris. The list includes bottles, bags, and six-pack yokes;
cups, plates, and utensils; fishing line, nets, floats, and ropes; diapers,
tampon applicators, and condoms; and polystyrene particles of all sizes,
Articles of metal, glass, paper, wood, and other substances are also
common.
What items of beach debris are most common?
These are the 12 most common debris items reported to the Center for Marine Conservation
from beach cleanups in 1988, in order of abundance. Together these items accounted for more
than 50% of the items collected.
Fragments of plastic
Small foamed-plastic particles
Plastic eating utensils
Metal beverage cans
Foamed-plastic cups
Glass beverage bottles
Plastic caps and lids
Paper pieces
Plastic trash bags
Other plastic bags
Glass pieces
Plastic beverage bottles
6-2
How Does the Harbor Rate Aesthetically?
In addition to its unsightly appearance, floatable debris in the marine
environment is a danger to fish, birds, marine mammals and turtles.
These animals can ingest floatable debris~with dire consequences —or
become fatally entangled in it. Still another possible undesirable effect
is damage to vessels through collision, fouling of propellers, or clogging
of engine intakes with floating waste.
Floatable debris originates from a variety of sources, including sewage
treatment plants and CSOs; solid-waste disposal) facilities; commercial
fishing vessels (nets and other fishing gear as well as general trash);
recreational, commercial, military, and research vessels; offshore drilling
operations; and the general public (beach and roadway litter). Data
compiled by the Center for Marine Conservation in 1989 showed that in
Massachusetts about 2% of the debris collected in beach cleanups
originated from sewage treatment plants. The national percentage
varied from less than 1 to about 3.5.
Cleanups at Cleanups were conducted at several Boston Harbor beaches in: 1988 and
Boston beaches 1989. These volunteer efforts were sponsored by the Massachusetts
produced more Office of Coastal Zone Management. In 1989, cleanup at four Boston
trash than Harbor beaches produced an average of 2090 Ib of trash per mile of
elsewhere in beach (Figure 6.1). This was 20 times more than found on Cape Cod
Massachusetts _ beaches,
The ocean outfall MWRA estimates that between 1000 and 50,000 plastic tampon
and CSO controls applicators enter the wastewater system each day. It is not known how
will reduce the many escape the screening and skimming processes and are discharged
amount of sewage- _-with the effluent. In addition, of course, some enter the harbor through
related debris | CSO discharges. The number of these and other sewage-related
floatable items will decline in Boston Harbor after construction of the
ocean outfall and implementation of CSO controls.
REPORT CARD Now 1992 1995 2000 2005
HOW DOES THE HARBOR RATE
AESTHETICALLY?
Aesthetics D Cc. B- B+ B+
6-3
How Does the Harbor Rate Aesthetically?
BEACH CLEANUP STATISTICS _ ~~
Ss
0 2500 5000
(Lb of trash per mile)
North Shore
me 453 [h/mile
Massachusetts
Bay
Metro Baston (overall)
es 1090 |b/ril
Revere Beach
eee PRUNES
Boston Horbor
Aad :
SE zm 370) Ib/mite
Orient Heights
E
me 2000) Ib/mile
Ci Is
SP nia
Quincy
1000 Ib/mile
South Shore
mus (790 [b/mie
Cape Cod _ Ln
mw 114 (b/mile
Figure 6.1. In the 1989 Coastsweep cleanup, Boston Harbor beaches produced more trash
per mile than beaches in other areas of Massachusetts.
6-4
7. PRESENT AND FUTURE: A SUMMARY
Some
improvements will
be rapid; others
will not be seen for
years
Halting of sludge
discharge will
improve water
clarity and reduce
concentrations of
pathogens and
toxic materials
Predictions for the Harbors Future
In Section 2, we pointed out that different contaminants have different
major sources. This fact has implications for how conditions will be
affected by various parts af the remediation plan. In addition, we
expect that different aspects of environmental quality will respond at
different rates. Changes in water quality, for example, should occur on
a scale of months to years; changes in sediment quality and fish
condition may take decades.
Cessation of Sludge Discharge
Sludge is one of the most important sources of contaminants to the
harbor. Thus, we can expect that plans to halt dumping of sludge ‘into
the harbor will also result in significant improvements in all contaminant
groups. Sludge discharge will cease by the end of 1991, and the sludge
will be made into fertilizer at the Fore River Staging Area.
Cessation of sludge discharge will reduce pathogen and toxic
contaminant discharge into the harbor by 30%, The major beneficiary
of pathogen reduction will be beaches in Winthrop and the outer
islands. Because sludge contributes about 25% of the total load of solid
material to Boston Harbor, water clarity is expected to improve with
cessation of sludge discharge, making a significant aesthetic contribution
to the harbor cleanup,
MWRA’s Harbor Studies is monitoring the amount of sludge now in the
harbor, and will compare the results to levels recorded after sludge is
no longer discharged. This program is a joint effort with the New
England Aquarium, the Massachusetts Audubon Society, and several
universities and public agencies. These groups will examine data on
fish, bottom-dwelling animals, and water circulation to measure the
recovery of the harbor over time.
Effluent-Related Changes
In general, effluent from the MWRA primary treatment plants on Deer
and Nut Islands is a major source of all groups of contaminants. As a
result, parts of the remediation plan that affect effluent (i.e., con-
struction of new plants to supply secondary treatment and construction
7-1
Present and Future: A Summary
flounder.
Cessation of sludge discharge is expected to make substantial improvements
The monitoring program designed to assess the effects of cessation of sludge discharge to the
Harbor has made predictions about what will happen. These predictions are being used as
scientific hypotheses to objectively analyze how much conditions have improved, These are -
some of the benefits expected as a result of the decrease in pathogen and toxic contamination
associated with halting of sludge discharge into Boston Harbor:
Rapid Improvements (1 Year or Less)
¢ The concentrations of bacteria indicative of recent sewage contamination will decline in
the clam beds near Deer Island and along Winthrop beaches.
* Turbidity will decrease as a result of the decrease in the particulate materia! discharged
into the harbor from both sludge and effluent.
Long-Term Improvements (5 to 10 Years)
¢ Sources of toxic contaminants to sediment will be reduced.
* Incidence of pathological conditions in fish will decline, including fin erosion in winter
* Concentration of toxic contaminants in shellfish will decline.
¢ Benthic communities in areas now impacted by sludge will show improved conditions of
Species richness, abundance, and diversity.
Changes in
effluent treatment
will further reduce
concentrations of
pathogens and
toxic materials
7-2
of the ocean outfall) will have a significant positive effect on all
contaminants. By 1995, sewage effluent from the new Deer Island
wastewater treatment plant will be discharged 15 km (9.5 miles) offshore
in Massachusetts Bay, in water 33 m (110 ft) deep. This represents a
Major milestone in the rehabilitation of the harbor. Beneficial effects
are a result of the improved capacity and efficiency of the new
treatment plant and the increased dilution that all contaminants will
experience, The concentration of pathogens and toxic materials will be
10 times less, thanks to the increased volume of water available for
dilution. Because nutrients and organic particles will also be more
dilute, the likelihood of oxygen depletion will be lower. On the other
hand, it is possible that the area surrounding the new outfall may be
more sensitive to reduced oxygen conditions,
The secondary
treatment plant
will benefit
Massachusetts
Bay, the site of the
new outfall
The remaining
pathogen and toxic
contamination
would be helped
by CSO control;
improvement
would be most
dramatic near
individual
overflows
Present and Future: A Summary
By the end of the decade, new treatment facilities will have been
constructed and the effluent discharged from the ocean outfall will be ©
receiving secondary treatment. The main effect of the change from
primary to secondary treatment will be an additional 30% reduction in
the toxic materials discharged to the ocean. The change will be
beneficial for Massachusetts Bay, but will have little effect on the
harbor. There will be little change in pathogen or nutrient
concentrations.
The MWRA Harbor Studies Department is conducting a long-term
program to provide information about conditions at the outfall site. By
determining conditions before and after the outfall is in operation, the
impacts of effluent discharges can be determined.
CSO Control
In addition to effluent and sludge, CSOs are a significant source of
contamination to Boston Harbor. Raw sewage released from CSOs is a
major cause of environmental degradation in Boston Harbor. Because
of the viruses and bacteria in untreated sewage, many areas in the
harbor fail to meet microbial standards for swimming and shellfishing.
Tf complete CSO contro] were implemented, the improvement in
pathogen concentration near individual discharges would be 100-fold,
and there would be a 25% reduction in beach closings harborwide. For
toxic contaminants, the harborwide decrease would be about 5%, again ©
with greater effects felt around individual overflows.
CSOs present a difficult problem in the remediation of Boston Harbor.
MWRA has just completed a plan for addressing the CSO issue. The
plan calls for installation of underground tunnels to store the overflow
of combined sewage until the main plant is ready to receive it.
Implementation of this plan will be difficult and expensive ~ the cost is
estimated at $1.2 billion. Unfortunately, even complete control of CSO
discharges will not totally eliminate the pathogen problem in the harbor
because a significant number of pathogens also come from stormwater
and rivers.
Harbor Studies has also developed a monitoring program to determine
the effects of CSOs on the environment. The baseline data on
microbial contamination from current sampling will be compared to
measurements made after completion of each stage of CSO control.
Present and Future: A Summary
Some sources of
contamination will
remain
Stormwater
contributes to-
contamination,
especially from
pathogens
Rivers contribute
. significant
amounts of metals
and pathogens
Contaminated
Sediments are a
source of toxic
materials
Remaining Problems
Unfortunately, even when the MWRA remediation plans are completed,
all sources of contamination to the harbor will not be eliminated.
Stormwater and rivers carry pollution in amounts that seem generally
unimportant in comparison to effluent and sludge, but which can be
significant when these other sources are reduced. In addition,
contaminants accumulated in Boston Harbor sediments are a major
concern, as discussed in Section 5.
Stormwater: Stormwater —water from rain or other precipitation — picks
up contaminants as it flows across the ground. Much of this water
eventually drains into surface waters, either by being collected in ditches
and drains and directed there, or by natural flow over the land until it
encounters a body of water. Depending upon what the Jand that it
flows over is used for, stormwater may become contaminated with
materials such as oil from roadways; pesticides and fertilizers from
cropland and gardens; and pathogens from sewage or from feces of
domestic, agricultural, or wild animals. In Boston Harbor, as in many
other coastal areas, pathogens in stormwater are a major issue. MWRA
has estimated that beach closings around the harbor would be reduced
by 40% if stormwater discharges were eliminated. In some localized
areas near discharges, the improvement would be 100-fold. This
suggests that after the remediation plans are complete, unless
stormwater discharges are reduced, there may still be some beach and
shellfish closures for short periods after rains in areas within a few
hundred yards of stormwater discharges.
Rivers: Rivers are also known sources of pollutants. In Boston Harbor,
flow from rivers is about half that from the sewage treatment plants.
The Charles is the largest river in the area, and discharges 7.5 m? of
water, into the Inner Harbor each second. phis compares to a flow of
20 m/s for the treatment plants and 10 m 3/s for all rivers combined.
The remaining large river discharges are the Neponset, Mystic, Chelsea,
Weymouth Fore, Weymouth Back, and Weir rivers, all in the southern
part of the harbor. In Boston Harbor, rivers are significant sources of
metals such as mercury and zinc and of feca) coliform bacteria.
Sediment: The problem of materials accumulated and stored in the
sediment at the bottom of the harbor is primarily a significant issue for
toxic contaminants. After the MWRA remediation projects are
complete, Boston Harbor waters probably will meet water quality
standards for these contaminants. However, the contaminants
Leaching from
hazardous waste
Sites remains a
problem
Boston Harbor
conditions are
summed up in a
report card
Present and Future: A Summary
remaining in the sediments will continue to provide some risk to fish
and shellfish living in these sediments. In addition, there is the danger
that materials could be released from the sediment to recontaminate the
overlying water. Sediment contamination is most likely to be a problem
in areas where sediment is deposited at a high rate. Such depositional
areas where contamination with toxic materials has been found include
Deer Island Flats, the Inner Harbor, and the portion of Dorchester Bay
bounded by Moon, Thompson’s, Long, and Spectacle islands.
Leaching of Hazardous Waste: A number of hazardous waste sites are
found in the Boston area. Leaching of materials from these sites is yet
another source of continued contamination to the harbor.
The Boston Harbor Report Card
As we looked at different aspects of the condition of Boston Harbor, we
gave each one a grade. As an overview of the contents of this report on
the status of the harbor, we present a complete report card covering all
the factors and all the grades (Figure 7.1). Some may think our grades
are too high; others that they are too low. We look to the future to
provide the answer.
7-5
Present and Future: A Summary
KEY TO GRADES
A Exce llant: Consistently maintains conditions characteristic of other clean coastal
sites.
B Good: Frequently exceeds Federal water quality standards and expectations for
an urban estuary.
C Satlstactory: Complies with Federal water quality standards and meets
expectations for an urban estuary.
D_ Poor: Sometimes fails to comply with existing standards or meet expectations for
an urban estuary; some uses of the harbor are maintained.
F Failing: Consistently fails to comply with Federal water quality standards or meet
expectations for an urban estuary; there is obvious environmental
degradation, and uses of the harbor are fost.
REPORT CARD FOR Boston Harbor
Now | 1992 | 1995 | 2000 | 2005
IS iT SAFE TO SWIM?
Swimming beaches D D+ | C Cc B
{S IT SAFE TO EAT FISH AND SHELLFISH?
Shellfish: Pathogens D- | D C- | C- | B-
Fish: Organic contamination C- | C- | C- | C+] B-
Fish: Metal contamination B- B- B- B B+
ARE MARINE RESOURCES PROTECTED?
Sediment contamination | D- D D C- C-
Water quality: Oxygen ; c- | c B B.
Water quality: Toxic contamination B- B B+} B+ | A-
Fish disease ; D- D + | C- C+
Benthic communities D- D C- C-
HOW DOES THE HARBORRATE AESTHETICALLY?
Aesthetics D C- | B- | B- | B+
OVERALL GRADE. D+ | C- | C | C+] B-
Figure 7.1. Thé Boston Harbor Report Card sums up our knowledge of present conditions
and our hopes for the future.
7-6
BIBLIOGRAPHY
1: The Problem and the Plan
MWRA. 1989. 5-Year Progress Report. Massachusetts Water
Resources Authority, Boston, MA.
2: Understanding the Problem
Battelle. 1989. A Pilot Study of the Deer Island and Nut Island
Sewage Outfalls within Boston Harbor, June 8-9, 1989. Report to
Massachusetts Water Resources Authority, Boston, MA.
Bumpus, D-F., W.S. Butcher, and W.D. Athern. 1951. Literature Survey
of Oceanograptuc Information Concerning Boston Harbor. Woods
Hole Oceanographic Institution Technical Report, Woods Hole, MA
Bumpus, D.F., W.S. Butcher, W.D. Athern, and C.G, Day. 1953.
Inshore Survey Report, Boston. Final Report. Woods Hole
Oceanographic Institution Technical Report, Woods Hole, MA.
Camp Dresser and McKee. 1985. Drogue Tracking Studies in Quincy
Bay. Report to the Massachusetts Department of Environmental
Quality Engineering, Boston, MA.
EG&G. 1984. Oceanographic Study of Various Outfall Siting Options
for the Deer Island Treatment Plant. Report to Havens and
Emerson/Parsons Brinkerhoff, Boston, MA.
Fitzgerald, M.G. 1980. Anthropogenic Influence on the Sedimentary
Regime of an Urban Estuary—Boston Harbor. Ph.D. Thesis,
Massachusetts Institute of Technology/Woods Hole Oceanographic
Institution Joint Program in Oceanography. WHOI Technical Report
80-38.
Keay, K.E., and C.R. Clavet. 1990, Distribution of a Sewage-Indicating
Bacterium in Boston Harbor Sediments. Presented at the Fifth
Annual Boston Harbor/Massachusetts Bay Symposium, Boston, MA.
Kelly, J. 1989. Report to the Massachusetts Water Resources
Authority, February 1989.
B-1
Bibliography
B-2
Knebel, HJ., R.R. Rendigs, and M.H. Bothner. 1990. Modern
sedimentary environments in Boston Harbor, Massachusetts.
Unpublished manuscript.
Kossik, R.F. 1987. Mathematical Simulation of Pollutant Transport in
Boston Harbor. MIT Sea Grant Report No. MITSG 87-3TN.
Massachusetts Institute of Technology, Cambridge, MA.
Massachusetts Institute of Technology. 1989. Transport of
Contaminated Sediments in Boston Harbor: Proposal to the
Massachusetts Water Resources Authority, Boston, MA, May 1989.
Massachusetts Institute of Technology. 1990. Transport of
Contaminated Sediments in Boston Harbor: Progress Report, March
1990, :
MWRA. 1989. 5-Year Progress Report. Massachusetts Water
Resources Authority, Boston, MA.
MWRA. ND. Staff Summary: Trend Analysis of Pollutant Loads to
the Deer Island and Nut Island Wastewater Treatment Facilities and
Boston Harbor. Massachusetts Water Resources Authority, Boston,
MA.
MWRA. 1990. Sludge Abatement Monitoring Program. Preliminary
Draft. Massachusetts Water Resources Authority, Boston, MA.
National Ocean Survey. 1977. Tidal Current Charts, Boston Harbor:
Scale 1:50,000. National Ocean Survey, Rockville, MD.
Science Applications International Corporation. 1990. REMOTS®
Sediment-Profile Photography Surveys of Boston Harbor, Dorchester,
Quincy, Hingham, and Hull Bays, June 1989 and May 1990. Draft
Report to the Massachusetts Walter Resources Authority, June 1990.
Signell, R.P., and B. Butman. 1990. Tidal Flushing of Boston Harbor.
Presented at the Fifth Annual Boston Harbor/Massachusetts Bay
Symposium, Boston, MA.
Smith, W. 1990. Sludge Fate Report. Draft Report. Massachusetts
Water Resources Authority, Boston, MA.
University of Massachusetts at Boston. 1989. Sediment-Water
Exchange of Contaminants in Boston Harbor: Proposal to the
Massachusetts Water Resources Authority, Boston, MA, May 1989.
Bibliography
University of Massachusetts at Boston. 1990. Sediment-Water
Exchange of Contaminants in Boston Harbor: Progress Report,
March 1990.
US. Geological Survey. 1990. Studies of Circulation and Pollutant
Transport in Massachusetts Coastal Waters: First Interim Report.
Woods Hole, MA.
3: Is It Safe To Swim in Boston Harbor?
MWRA. 1990. Sludge Bacterial Monitoring. Draft Report.
Massachusetts Water Resources Authority, Boston, MA.
Rex, A. 1989. Combined Sewer Overflow Monitoring Results. MWRA
Staff Summary. Massachusetts Water Resources Authority, Boston,
MA.
Rex, A. 1990. Preliminary Summary of Results and Condition of 1989
MWRA Combined Sewer Overflow Receiving Water Monitoring
Program. Draft Report. Massachusetts Water Resources Authority,
Boston, MA.
4: Is It Safe To Eat Fish and Shellfish?
Battelle. 1988. Mussel Watch 2-Year Report. Report to the National
Oceanic and Atmospheric Administration, Rockville, MD.
Boehm, P.D., W. Steinhauer, and J. Brown. 1984. Organic Pollutant
Biogeochemistry Studies Northeast U.S. Marine Environment, Part 1:
The State of Organic Pollutant (PCB, PAH, Coprostanol)
Contamination of the Boston Harbor - Massachusetts Bay - Cape
Cod Bay System: Sediments and Biota. Report to the National
Oceanic and Atmospheric Administration, Rockville, MD.
DuPont, H.L. 1986. Consumption of raw shellfish: Is the risk now
unacceptable? [Editorial]. New England Journal of Medicine
314:707-708.
Enseco. 1990. Bioaccumulation Assessment for the Massachusetts
Water Resources Authonity’s National Pollutant Discharge
Elimination System Permit Monitoring Program. 1988 Deployment,
Final Report to the Massachusetts Water Resources Authority,
Boston, MA.
Bibliography
B-4
Enseco. 1990. Bioaccumulation Assessment for the Massachusetts
Water Resources Authority’s National Pollutant Discharge
Elimination System Permit Monitoring Program. 1989 Deployment.
Draft Report to the Massachusetts Water Resources Authority,
Boston, MA.
Farrington, J.W., R.W. Risebrough, P.L. Parker, A.C. Davis, B. de
Lappe, J.K. Winters, D. Boatwright, and N.M. Frew, 1982.
Hydrocarbons, Polychlorinated Biphenyls, and DDE in Mussels and
Oysters from the U.S, Coast, 1976-1976—the Mussel Watch. WHOT
Technical Report 82-42. Woods Hole Oceanographic Institution,
Woods Hole, MA.
Grimes, DJ. and G.R. Heufelder. 1990. The Buzzards Bay Project
Synthesis Report on Pathogen Issues. Available from Massachusetts
Coastal Zone Management, Marion, MA.
Hillman, R.E., M.S. Connor, and R.A. McGrath. 1989. Ratios of
Edible Tissue to Whole Body PCB Concentrations in Flounder and
Lobster from New Bedford Harbor. Final Report to the U.S.
Environmental Protection Agency, Office of Marine and Estuarine
Protection, Washington, DC.
Metcalf & Eddy, Inc. 1988. Review of Historical Data for
Characterization of Quincy Bay Contamination: Task I Report.
Prepared for U.S. Environmental Protection Agency, Water Quality
Branch, Boston, MA.
Metcalf & Eddy, Inc. 1988. Analysis of Risks from Consumption of
Quincy Bay Fish and Shellfish. Prepared for U.S. Environmental
Protection Agency, Water Quality Branch, Boston, MA.
Metcalf & Eddy, Inc. 1988. Summary Report for Assessment of
Quincy Bay Contamination: Task V Report. Prepared for U.S.
Environmental Protection Agency, Water Quality Branch, Boston,
MA.
Morse, D.L., J.J. Guzewich, J.P. Hanrahan, R. Stricof, M. Shayegani, R.
Deibel, J.C. Grabau, N.A. Nowak, J.E. Herrmann, G. Cukor, and
N.R. Blacklow. 1989. Widespread outbreaks of clam- and oyster-
associated gastroenteritis: Role of Norwalk virus. New England
Journal of Medicine 314:678-81.
New England Aquarium. 1988, Bioaccumulation of Metal and Organic
Contaminants in the Mussel, Mytilus edulis, Transplanted to Boston
Harbor, Massachusetts. Report to Camp Dresser & McKee, Inc.,
Boston, MA.
Bibliography
NIEHS. ND. Symposium on Chemically Contaminated Aquatic Food
Resources and Human Cancer Risk: Epilogue. National Institute of
Environmental Health Sciences.
NOAA. 1988. National Status and Trends Program Benthic
Surveillance Project: Summary Report, 1984-86. U.S. Department of
Commerce, National Oceanic and Atmospheric Administration,
National Marine Fisheries Service, Northeast Fisheries Center.
Schwartz, J.P. 1987. PCB Concentrations in: Marine Fish and Shellfish
from Boston and Salem Harbors, and Coastal Massachusetts.
Progress Report. Publication #14,997-36-110-8-87-CR. Division of
Marine Fisheries, Salem, MA.
U.S. Environmental Protection Agency. 1988. A Histopathological and
Chemical Assessment of Winter Flounder, Lobster and Soft-Shelled
Clam Indigenous to Quincy Bay, Boston Harbor, and an i Sine
Evaluation of Oysters Including Sediment (Surface and Cores)
Chemistry. Task IT and IIIf Report. Environmental Research
Laboratory, Narragansett, RI.
Wallace, G.T., RP. Eganhouse, L.C. Pitts, and B.R. Gould. 1988.
Analysis of Contaminants in Marine Resources. Final Report by the
University of Massachusetts at Boston to the Massachusetts
Department of Environmental Quality Engineering and the US.
Environmental Protection Agency.
Ziskowski, JJ., L. Despres-Patanjo, RA. Murchelano, A.B. Howe, D.
Ralph, and S. Atran. 1987. Disease in commercially valuable fish
stocks in the Northwest Atlantic. Marine Pollution Bulletin
18(a):496-504,
5: Are Fish and Other Marine Resources Being Protected?
Battelle. 1990. Phase IV Final Report, National Status and Trends
Mussel Watch Program. Collection of Bivalves and Surficial
Sediments From Coastal U.S. Atlantic and Pacific Locations and
Analysis for Organic Chemicals and Trace Elements. Report to U.S
Department of Commerce, National Oceanic and Atmospheric
Administration, Ocean Assessments Division, Rockville, MD.
Blake, J.A., NJ. Maciolek, and P. Rosen. ND. Benthic Infaunal
Communities of Boston Harbor.
B-5
Bibliography
B-6
Boehm, P.D., W. Steinhauer, and J. Brown. 1984. Organic Pollutant
Biogeochemistry Studies Northeast U.S. Marine Environment. Part 1:
The State of Organic Pollutant (PCB, PAH, Coprostanol)
Contamination of the Boston Harbor - Massachusetts Bay - Cape
Cod Bay system: Sediments and Biota. Final Report from Battelle
Ocean Sciences to the National Oceanic and Atmospheric
Administration, Rockville, MD.
Carr, R.S., R.E. Hillman, and J.N. Neff. Field assessment of
biochemical and histopathological indicators of stress for winter
flounder. Unpublished manuscript, Battelle, Duxbury, MA.
COE. 1981. Environmental Assessment for Boston Harbor
Maintenance Dredging. U.S. Army Corps of Engineers, New
England Division, Waltham, MA.
Couch, J.A, and D.R. Nimmo. 1974, Detection of interactions between
natural pathogens and pollutants in aquatic animals. In: Hood, M.A.
and R.R. Miller (eds). Proceedings Gulf Coast Regional Symposium
on Diseases of Aquatic Animals. Louisiana State University, Cent.
Wetland Resour. Pub. No. LSU-SG-74-05.
DEQE. 1986. Boston Harbor Water Quatity Survey and Wastewater
Discharge Data. Massachusetts Department of Environmental
Quality and Engineering, Division of Water Pollution Control,
Westborough, MA.
DEQE. 1987. Boston Harbor Water Quality Survey and Wastewater
Discharge Data. Massachusetts Department of Environmental
Quality and Engineering, Division of Water Pollution Control,
Westborough, MA.
Gallagher, E.D. and J.P. Grassle. 1989, Assessment of the Savin Hill
and Fox Point Benthic Community Structure before Modification of
the Fox Point Combined Sewer Overflow, 1987. Executive Summary.
Report to the Massachusetts Water Resources Authority, Boston,
MA.
Gilbert, T., G.C. McLeod, R. Maehl, KV. Ladd, A. Clay, and A. Barker.
1972. Trace Metal Analysis of Boston Harbor Water and Sediments.
Report by the New England Aquarium to the Commonwealth of
Massachusetts, Divison of Water Pollution Control. Contract Report
70-26.
Hall, M.P. Feb 1990. Boston Harbor Monitoring Report: October 1986
to October 1989. Massachusetts Audubon Sociely, Boston, MA.
Bibliography
Isaac, R.A. and J. Delaney. 1972, Toxic Element Survey, Progress
Report No. 1. Massachusetts Division of Water Pollution Control.
Publication No. 6108.
Iwanowicz, H.R. R.D. Anderson, and B.A. Ketschke. 1973. A Study of
the Marine Resources of Hingham Bay. Mono. Ser. No. 14.
Massachusetts Division of Marine Fisheries, Boston, MA.
Long, E.R. and L.G, Morgan. 1990. The Potential for Biological
Effects of Sediment-Sorbed Contaminants Tested in the National
Status and Trends Program. NOAA Technical Memorandum NOS
OMA 52. U.S. Department of Commerce, National Oceanic and
Atmospheric Administration, National Ocean Service, Seattle, WA.
Malins, D.C., B.B. McCain, D.W. Brown, M.S. Myers, M.M. Krahn, S-L
Chan. 1984. Toxic chemicals, including aromatic.and chlorinated
hydrocarbons and their derivatives, and liver lesions in white croaker
(Genyonemus lineatus) from the vicinity of Los Angeles.
Environmental Science & Technology 21:765-770.
Mearns, A.J., and M.J. Sherwood. 1977. Distribution of neoplasms and
other diseases in marine fish relative to the discharge of waste water.
Ann. N.Y. Acad. Sci. 298:210-224.
Murchelano, R.A. 1988. Fish as Sentinels of Environmental Health.
U.S. Department of Commerce. Nationa] Oceanic and Atmospheric
Administration. NOAA Technical Memorandum. NMFS-F/NEC-61.
Murchelano, RA. and R.E. Wolke. 1985. Epizootic carcinoma in
winter flounder, Pseudopleuronectes americanus. Science 228:587-589.
MWRA. 1987. Secondary Treatment Facilities Plan, Volume V,
Appendix X: Bioaccumulation. Massachusetts Water Resources
Authority, Boston, MA.
NOAA. 1987. National Status & Trends Program — Draft Interpretive
Report, National Benthic Surveillance Project, Cycle I. U.S.
Department of Commerce, National Oceanic and Atmospheric
Administration, National Marine Fisheries Service, Northeast
Fisheries Center.
NOAA. 1988, Nationa} Status and Trends Program Benthic
Surveillance Project: Summary Report, 1984-86. U.S. Department of
Commerce, National Oceanic and Atmospheric Administration,
National Marine Fisheries Service, Northeast Fisheries Center.
Bibliography
B-8
O’Connor, J.S., JJ. Ziskowski, and R.A. Murchelano. 1987. Index of
Pollutant-Induced Fish and Shellfish Disease. U.S. Department of
Commerce, National Oceanic and Atmospheric Administration,
National Ocean Service. NOAA Special Report.
Robinson, W.E., TJ. Coffey, and P.A. Sullivan. 1990. New England
Aquarium’s Ten Year Boston Harbor Monitoring Program. First
Report (March 1987 - July 1989). Draft Report. New England
Aquarium, Boston, MA.
SAIC. 1990. REMOTS® Sediment-Profile Photography Surveys of
Boston Harbor, Dorchester, Quincy, Hingham, and Hull Bays, June
1989 and May 1990. Report No. SAIC-90/7578&236. Science
Applications International Corp., Woods Hole, MA.
Sass, S.L., and R.A. Murchelano. 1988. Hepatic tumors and other liver
pathology in Massachusetts flatfish. (Abstract). Aquatic Toxicology
11:420-421.
Sherwood, M.J., and AJ. Mearns, 1977. Environmental significance of
fin erosion in sourthern California demersal fishes. Ann. NY Acad.
Sci. 298:177-189.
Shiaris, M.P., and D. Jambard-Sweet. 1986. Polycyclic aromatic
hydrocarbons in surficial sediments of Boston Harbor, Massachusetts,
U.S.A. Marine Pollution Bulletin 17:469-472. :
Sullivan, P.A. and W.E. Robinson. 1990. The Health of Winter
Flounder from Boston Harbor: A Summary of Results from “Fish
Day,” May 13, 1989. New England Aquarium, Boston, MA.
Sunda, W.G., and S.A. Huntsman. 1989a. Concentrations and
Chemical Speciation of Trace Metal Contaminants jn Coastal Waters
of the Northeastern United States. Summary Progress Report for
FY88. Submitted to Ocean Assessments Division, National Ocean
Service, NOAA by NMFS Beaufort Laboratory.
Sunda, W.G., and S.A. Huntsman. 1989b, Concentrations, Chemical
Speciation and Toxicity of Trace Metal Contaminants in Coastal
Waters of the Northeastern United States. Summary Progress Report
for FY89. Submitted to Ocean Assessments Division, National
Ocean Service, NOAA by NMFS Beaufort Laboratory.
Sung, W. 1990. Water Quality: Metals. Massachusetts Water Resources
Authority, Boston, MA.
Bibliography
U.S. Environmental Protection Agency. 1988. A Histopathological and
Chemica] Assessment of Winter Flounder, Lobster and Soft-Shelled
Clam Indigenous to Quincy Bay, Boston Harbor, and an in Situ
Evaluation of Oysters Including Sediment (Surface and Cores)
Chemistry. Task Il and I Report. Environmental Research
Laboratory, Narragansett, RI.
Wallace, G.T., JH. Waugh, and K.A. Garner. 1988. Metal distribution
in a major urban estuary (Boston Harbor) impacted by ocean
disposal. Chapter 7 in Wolfe, D.A. and T.P. O'Connor (eds.), Urban
Waste in Coastal Marine Environments, Volume 5 of Oceanic
Processes in Marine Pollution. Kreiger, Malibar, FL.
Wallace, G.T., C. Krahforst, L. Pitts, J. Shine, M. Studer, and C.
Bollinger, 1990. Assessment of the Chemical Composition of the
Fox Point CSO Effluent and Associated Subtital-and Intertidal
Environments. Draft Final Report from the University of
Massachusetts at Boston to the Massachusetts Department of
Environmental Protection.
White, RJ. 1972. The Distribution and Concentration of Selected
Metals in Boston Harbor Sediments. M.S. Thesis, Northeastern
University, Boston, MA.
Williams, J.W. 1981. The Occurrence of Fin Erosion in Winter
Flounder, Pseudopleuronectes americanus, from the Vicinity of Boston
Harbor, Massachusetts. Interhouse Report, Battelle, Duxbury, MA.
Ziskowski, J.J., L. Despres-Patanjo, R.A. Murchelano, A.B. Howe, D.
Ralph, and S. Atran. 1987. Disease in commercially valuable fish
stocks in the Northwest Atlantic. Marine Pollution Bulletin
18(a):496-504.
6: How Does the Harbor Rate Aesthetically?
Maciolek, N. 1990. Report on Floatable Debris on Boston Harbor
Beaches. Massachusetts Executive Office of Environmental Affairs,
Coastal Zone Management, Boston, MA.
Robinson, W.E., TJ. Coffey, and P.A. Sullivan. 1990. New England
Aquarium’s Ten Year Boston Harbor Monitoring Program. First
Report (March 1987 - July 1989). Draft Report. New England
Aquarium, Boston, MA.
B-9
Bibliography
B-10
7; What Can We Expect in the Future?
MWRA. 1990 (Draft). Sludge Abatement Monitoring Program.
Massachusetts Water Resources Authority, Boston, MA.
MWRA. 1989. Staff Summary: Costs and Benefits of Different Harbor
Projects. Massachusetts Water Resources Authority, Boston, MA.
Robinson, W.E., TJ. Coffey, and P.A. Sullivan. 1990. New England
Aquarium’s Ten Year Boston Harbor Monitoring Program. First
Report (March 1987 - July 1989). Draft Report. New England
Aquarium, Boston, MA.
ACKNOWLEDGMENTS
This report was conceived and coordinated by Michae] Connor and
edited by Victoria Gibson. Sections were written by Karen Foster,
Victoria Gibson, Robert Hillman, Kenneth Keay, Andrea Rex, Damian |
Shea, Wendy Smith, and Windsor Sung. Graphics were produced by
Julie Uller. The draft report was reviewed by Eric Adams, Cindy Lee,
Francoise Morel, John Ryther, Keith Stolzenbach, and Gordon Wallace.
Massachusetts Water Resources Authority
Charlestown Navy Yard
100 First Avenue
Boston, MA 02129
(617) 242-6000
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