shellfish harvested nearby (e.g., Versar 1985). Site rankings may be 

 used to establish priorities for investigation of contaminant sources and 

 for cleanup. Maps of chemical residue data or risk estimates provide 

 a geographic overview of the condition of resources linked to human 

 exposure. Second, priority chemicals can be identified according to 

 associated health risks or indices of relative hazard (e.g., Ames et al. 

 1987) . Finally, various fishery species and size (or weight) classes within 

 species can be ranked according to relative risks. 



Risk assessment is an important analytical tool for developing environ- 

 mental criteria and guidelines. For example, water quality criteria 

 derived by U.S. EPA (1980b, 1986h) are based in part on human health 

 risk assessment. FDA uses quantitative risk assessment to estimate 

 potential human health risks, which are considered together with 

 economic factors in developing action levels for chemical con- 

 taminants in fishery products (U.S. FDA 1984). Risk assessment 

 models can be used to develop guidelines on maximum advisable 

 contaminant concentrations in recreationally harvested species. Such 

 guidelines can contribute to development of target cleanup criteria 

 established to develop remedial actions for contaminated sites. 



The results of risk assessments may be used to inform the public about 

 the relative health risks of various fishery species and geographic 

 locations. Providing the recreational public with such information 

 allows for individual choice in determining harvest area, target species, 

 consumption rates, and other factors based on relative risk. Further- 

 more, risk assessment may contribute to management decisions by 

 federal, state, and local agencies, which may include: 



• Investigating sources of pollution 



• Reducing exposure potential by implementing pollution con- 

 trols 



• Restricting fishery harvests by geographic area or by species 



9- Issuing public advisories or controls to limit: 



- Geographic area of harvesting 



- Harvest season 



- Harvest methods 



- Species harvested 



- Catch number 



- Size range harvested 



- Consumption rate. 



Further information on the relationship between risk assessment and 

 risk management maybe found in Lowrance (1976), U.S. EPA (1984b), 

 Lave and Menkes (1985), Ames et al. (1987), Lave (1987), Russell and 

 Gruber (1987), and Travis et al. (1987). 



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