STATE OF THE GREAT LAKES 2005
CAN WE EAT THE FISH?
Generally yes, if appropriate fish consumption advisories are followed.
Fish are an important part of a healthy diet because
they contain high-quality protein and essential
nutrients, are low in saturated fat and contain
omega-3 fatty acids.
The Issues
There may be health risks associated with
consumption of Great Lakes fish if the
contaminant concentrations in the fish are above
recommended levels. These health risks are
particularly important for sensitive populations,
such as women who are or may become
pregnant, nursing mothers, young children and
subsistence fishers.
All eight Great Lakes states, Tribes, First Nations,
and the province of Ontario currently advise
people to limit their intake of certain Great Lakes
fish species or sizes of fish due to chemical
contamination.
Currently, the goal of unlimited human
consumption of Great Lakes fish is not being met
because of continued and past inputs of
persistent toxic substances such as PCBs,
chlordane, dioxin, mercury and toxaphene.
The Indicator
Levels of many persistent bioaccumulative toxic
(PBT) chemicals in the Great Lakes basin have
declined since the 1970s as a result of restrictions and
bans on the use and production of some chemicals
(e.g., PCBs, pesticides) and reductions in the release
and emissions of other chemicals (e.g., dioxins,
mercury). Because PBT chemicals persist, continue to
be released into the environment and accumulate in
organisms, these contaminants continue to be a
significant concern.
Chemical contaminants are currently introduced into
the waters of the Great Lakes primarily from
atmospheric deposition and contaminated
sediments, although other sources exist. Once
transferred to the water, some contaminants can be
ingested, absorbed and accumulated in Great Lakes
fish. This process is known as bioaccumulation. As
these fish are ingested by other predator fish, the
contaminants accumulate at increasingly higher
concentrations. As a result, the large fish usually
desired for human consumption are often those
carrying the greatest amounts of contaminants. This
process is called biomagnification.
As an indicator of chemical contamination of fish,
and to assess potential human exposure to PCBs
through sport fish consumption, this report
evaluates PCB levels in coho salmon and lake trout
by qualitatively comparing these levels to the fish
consumption guidelines found in the Protocol for a
Uniform Great Lakes Sport Fish Consumption Advisory,
developed by the eight Great Lakes states, and in the
Guide to Eating Ontario Sport Fish. Although not
intended as fish consumption advice, this report
assesses the edibility of coho salmon and lake trout
from the Great Lakes.
Coho salmon. Photo: U.S. EPA Great Lakes
National Program Office.
The Assessment
Concentrations of banned contaminants in fish tissue
are decreasing over time, but many are still present
at levels that can affect humans. In recent years, PCB
concentrations in coho salmon and lake trout in all of
the Great Lakes often exceeded health protection
values set by the Great Lakes Protocol for unrestricted
fish consumption or the Guide to Eating Ontario Sport
Fish for consumption of 8 meals per month.
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CAN WE EAT THE FISH?
2.5
2
1.5
1
0.5
0
Lake Superior Coho Salmon
Lake Huron Coho Salmon
Do not eat
Oner
eal every two months
One meal a month
1.0
0.2
a o
&.
K9 Kl K9 K9 K9 K9 N? N? Kt ^v
One meal a week
Lake Michigan Coho Salmon
Unrestricted consumption
Lake Erie Coho Salmon
One meal every two months
One meal a month
JdU
? 1-5
-
0.2 °- 0
0.05 ,£
Do not eat
One meal every two month
CJ <\J\<\J <\J <\J <\J <\J \J
One meal a week Unrestricted consumption
0.2
0.05
Lake Ontario Coho Salmon
2
1.5
0.5
0
£ne
One meal a week
Lake Superior Lake Trout
Lake Huron Lake Trout
month Eight
Lake Erie Lake Trout
Do not eat
I Four meals a month I |
Eightmealsamonthj |
Lake Ontario Lake Trout
0.305
0.153
O 1.5
Do not eat
llLn i
0.610
0.305
0.153
0.2
0.05
Year
Application of a uniform sport fish consumption advisory protocol (A) and a guide to eating
Ontario sport fish (B) for PCB concentrations, measured in parts per million (ppm), in coho
salmon and lake trout, respectively. Absence of a bar indicates fish tissues were not
analyzed for a given year. Note the scale variations for PCB concentrations and total
number of years reported. Source: State of the Lakes 2005 report.
Year
Current Actions
Fish consumption advisories issued by Great Lakes
states and the province of Ontario range from
recommending no or limited consumption of
specific sizes of fish, fish species and/or fish from
particular water bodies, to unrestricted
consumption of fish from various locations.
Actions Needed
Increased awareness of the fish consumption
advisories by Great Lakes basin residents,
especially in sensitive populations, is needed.
Monitoring of contaminant levels in human tissues
must continue. More knowledge of the potential
negative health effects from the exposure to PBT
chemicals is needed.
Although concentrations of many contaminants
have decreased in fish tissue, fish consumption
advisories continue to be in effect in the Great
Lakes for PCBs, mercury and other contaminants.
Elevated concentrations of these compounds
indicate that the domestic release of toxic
chemicals, inputs from long range atmospheric
transport and remaining legacy sources of banned
contaminants in the Great Lakes region (such as
contaminated sediments, old agricultural fields,
landfills and PCB transformer storage sites)
continue to be a problem and must be remediated.
Further research is needed regarding the control of
non-native species and their ability to alter the
pathways and fate of persistent toxic substances.
Non-native species may change the contaminant
accumulation pattern among fish, particularly near
the top of the food chain.
To Learn More
For further information about Great Lakes sport
fish contaminant monitoring, refer to the State of
the Great Lakes 2005 report which, along with
other Great Lakes references, can be accessed at
www.epa.gov/glnpo/solec. For information on
local fish consumption advisory programs, visit
www.epa.gov/ost/fish (United States) and
www.ene.gov.on.ca/envision/guide/index.htm
(Ontario).
02/06
EPA 905-F-05-002
IISG-05-08
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