In sediments in the southwestern parts of the Bering Sea 

 and the Bering Strait, the PAH concentration is primarily 

 below the detection limits of the method. At the same time, 

 seven PAH's were detected near St. Lawrence Island and 

 northeast of there (Table 7). Their total concentration ranged 

 from 0.87 to 4.8 |ig/kg on a dry wt. basis, while BbF accounted 

 for the major part (up to 66.77%). In addition to the PAH's 

 listed in Table 7, low amounts of BaA and IP were detected in 

 the southeastern part of the Bering (up to 10 and 10.48 wt'/r, 

 respectively). The total PAH concentration in the sediment of 

 the Chukchi Sea varied from 8.3 to 76.4 |ig/kg on a dry wt. 

 basis. These values were higher than for the Bering Sea, and 

 BbF accounted for 56.4% of this total. Seven representatives 

 of the 4- to 5-nucleated PAH's were identified. 



Benzo(a)pyrene was present in nearly all of the sediment 

 samples from the Chukchi Sea. The highest was 4.5 |ig/kg on 

 a dry wt. basis (Station 40) which is about x3 higher than was 

 measured in the sediment samples from the Bering Sea. 



Publisheddata(Malinsefa/.,1985;Israel&Tsyban, 1987; 

 Kirso et ai, 1988) and those obtained by us show a relatively 

 low level of PAH pollution of water, biota, and sediments in the 

 Bering and Chukchi Seas. Of more concern, however, is the 

 accumulation of the dangerous carcinogen BbF (Fig. 6) which 

 was observed in these ecosystems both in the process of 

 circulation and in biosedimentation. 



Apparently entering into the marine environment as part 

 of oil pollution, BkF appears to have become concentrated in 

 the neuston, suspended matter, and bottom sediments of these 

 regions. Minor portions also seem to reenter the surface layer. 

 Finally, this carcinogen enters the food chain making it a 

 possible risk to man under the right conditions. 



(C) 



(d) 



Fig, 6. Distributionof PAH's (wt?}-) in compartments of the ecosystem of the 

 Chukchi Sea (Station 74): near bottom layer (a); sediment (b); 

 suspended matter (c); neuston (d). 



TABLE 7 



Concentration (%) of individual compounds of total PAH concentration in the bottom sediments of the 

 Bering Sea. the Bering Strait and the Chukchi Sea. 



307 



