EMW Initial Phase Report 



found in the NOAA S&T data and the IMW data. Possibly this reflects similar overall use and/or 

 release of PCBs in the IMW Phase I region, but this hypotheses cannot be tested unless adequate 

 production and use data becomes available. 



OVERVIEW OF CHLORINATED PESTICIDE AND PCB DATA 



Many of the analyte tissue concentrations are at, or below, detection limits. This is good 

 news from an environmental quality perspective. There are no samples for which contaminant 

 concentrations exceed the various national and international recommended action limits for these 

 individual chemicals in seafood destined for human consumption. This does not address the issue 

 of the long term effects of exposure at low concentrations of these chemicals (Colborn et al, 1993; 

 Sheehan et al, 1984; Slorach and Vaz, 1983). 



We must keep in mind that the IMW Project was designed to provide a broad geographic 

 assessment only, and at only one point in time. We suspect that concentrations of most of the 

 chlorinated pesticides and chlorobiphenyls are on a curve of decreasing concentrations over time; 

 perhaps similar to that experienced in the United States in the mid-to-northem latitudes of the 

 Western Hemisphere (O'Connor, 1991). However, we cannot be certain until some measures of a 

 time series, either through continuation of a time series of IMW stations and analyses in the near 

 future, or by judicious selection and analyses of sediment cores in key locations, provides 

 definitive proof. 



Local areas of intense pollution of major consequence may not have been detected. The 

 original sampling plan was intended to survey coastal contamination from the range of human land 

 uses and was not designed to detect "hot spots". This initial survey should be followed by a more 

 detailed assessment of specific embayments by participating Host-Country scientists and 

 colleagues in their countries using similar techniques. In addition, the stations identified in the 

 EMW data set as having significantly elevated concentrations of chlorinated pesticides or 

 chlorobiphenyl congeners do require further investigation at the regional and local level into the 

 reason for these elevated concentrations in order to provide effective protection of valuable living 

 natural resources and to minimize future threats to public health. 



POLYNUCLEAR AROMATIC HYDROCARBONS (PAHS) 



Although funding constraints for the Initial Implementation Phase restricted chemical 

 analysis to the chlorinated biocides, scientific and environmental issues of interest in fossil fuel 

 hydrocarbons persist. As part of GERG's routine screening methodology for trace organic 

 contaminants in environmental samples (and with no contractual commitment or funding from the 

 International Mussel Watch Program) concentrations of several PAHs (Table 15) were determined 



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