1988 strandings was - 142 ± 1 10 ^g/g (wet weight). Kuehl, et al. (1991 ) also 

 analyzed for PCBs, and other halogenated compounds in a different subset of 

 dolphins (n = 7) from the 1987-1988 stranding; the results for CHs were similar 

 to those found by Geraci. 



In this study, we analyzed samples of blubber, liver and kidney from 20 

 bottlenose dolphins from the 1990 Gulf Coast stranding for a broad spectrum of 

 chemical contaminants such as (THs and certain toxic metals. Chlorinated 

 hydrocarbons are among the most widespread and persistent chemical 

 contaminants in the near coastal environment and can accumulate in the lipid-rich 

 blubber tissue as well as in the liver of marine mammals. Several metals were 

 analyzed because of their toxicological significance and their possible 

 accumulation in the liver, as well as in the kidney — an extrahepatic organ with a 

 specific affmity to certain toxic metals (e.g. mercury). 



In additon to CHs and toxic metals, polycyclic aromatic hydrocarbons 

 (PAHs) are ubiquitous pollutants in urban areas. However, because of extensive 

 metabolism by marine mammals and fish, PAHs are not detected in their original 

 fomi. The presence of PAH metabolites can be determined by analysis of bile, a 

 biological fluid which accumulates PAH metabolites, and has been effective in 

 demonstrating PAH-exposure in harbor seals and sea lions (Varanasi et al. 1991). 

 However, dolphins do not have gall bladders, thus precluding the use of this 

 technique. Levels of DNA-xenobiotic iddncts (Varanasi et al. 1989A) which 

 represent the binding of contaminants such as carcinogenic PAHs to DNA may be 

 a useful indicator of exposure to PAHs, and hence we attempted to analyze liver 

 samples for DNA-adducts. 



The results to date showed that several of these stranded dolphins contained 

 elevated concentrations of PCB, DDTs and certain metals. DNA analyses showed 

 that samples with better integrity need to be tested before drawing any firm 

 conclusion with regard to PAH-exposure of the manunals. 



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