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12 SEAFOOD SAFETY 



significant include reproductive effects from polychlorinaied biphenyls (PCBs) and 

 methylmercury; carcinogenesis from selected congeners of PCBs, dioxins, and 

 dibenzofurans (all of which appear to act primarily by binding to a single type of 

 receptor); and, possibly, parkinsonism in the elderly from long-term mercury exposure. 

 Several other metallic and pesticide residues also warrant attention. 



Principal Conclusions 



• A small proportion of seafood is contaminated with appreciable 

 concentrations of potentially hazardous organic and inorganic chemicals from both 

 natural and human sources. Some examples of the risks that may be significant include 

 reproductive effects from PCBs and methylmercury, and carcinogenesis from selected 

 PCB congeners, dioxins, and chlorinated hydrocarbon pesticides. 



• Consumption of some types of contaminated seafood poses enough risk that 

 efforts toward evaluation, education, and control of that risk must be improved. 



• Present quantitative risk assessment procedures used by government agencies 

 should be improved and extended to noncancer effects. 



• Current contaminant monitoring and surveillance programs provide an 

 madequate representation of the presence of contaminants in edible portions of 

 domestic and imported seafood, resulting in serious difficulties in assessing both risks 

 and specific opponunities for control. 



• Due to the unevenness of contamination among species and geographic 

 sources, it is feasible to narrowly target control efforts and still achieve meaningful 

 reductions in exposure. 



• The data base for evaluating the safety of cenain chemicals that find their 

 way into seafood via aquaculture and processing is too weak to suppon a conclusion 

 that these products are being effectively controlled. 



Principal Recommendations 



• Existing regulations to minimize chemical and biological contamination of the 

 aquatic environment should be strengthened and enforced. 



• Existing FDA and state regulations should be strengthened and enforced to 

 reduce the human consumption of aquatic organisms with relatively high contaminant 

 levels (e.g., certain species from the Great Lakes with high PCB levels, swordfish and 

 other species with high methylmercury levels). 



• Federal agencies should actively support research to determine actual risks 

 from the consumption of contaminants associated with seafood and to develop specific 

 approaches for decreasing these risks. 



• Increased environmental monitoring should be initiated at the state level as 

 part of an overall federal exposure management system. 



• States should continue to be responsible for site closures, and for issuing 

 health and contamination advisories tailored to the specific consumption habits, 

 reproductive or other special risks, and information sources of specific groups of 

 consumers. 



• Public education on specific chemical contaminant hazards should be 



