PAH's in Suspension 



It is known that PAH's, being of poor water solubility, are 

 readily sorbed onto suspended particulate matter, accumulated 

 in bottom sediments and are sorbed by biota (Fig. 1 ). In the 

 Bering Sea and the Bering Strait, five suspended matter samples 

 werecollectedatdepthsof 70and 170 m. The total concentration 

 of PAH's in the suspended matter of the surface layer reached 

 1,620 ng/g, but in deeper horizons the maximum was only up 

 to 1,018 ng/g (Station 110). 



In the samples at the surface in the Bering Sea the following 

 4-6-nucleated PAH's (Table 4) were identified (wt %): BaA 

 plus Chr, 19.8; Py, 44.8; BeP, 22.0; BbF, 14.8; BaP, 12.8; and 

 BkF, 2.5. It should be noted that the weight composition of 

 PAH's in these suspended sediment samples varied within a 

 wide range depending on the regions sampled; for example, at 

 some locations the concentration of BbF reached 48%, that of 

 BaA plus Chr, 42%, and BeP, 22%. At the same time, at deeper 

 horizons, BeP concentration increased up to 78% of the total 

 PAH's concentration and, correspondingly, the percent 

 composition of the above PAH's decreased. The BaP 

 concentration in the suspended matter never exceeded 1 5% of 

 total PAH concentration. 



In the Chukchi Sea the concentration of total PAH's in 

 suspended matter in the upper horizons. Station 45, was 

 3,544 ng/g, and at 40 m it was 89.0 ng/g. The PAH's in the 

 suspended matter samples at the surface from the western part 

 of this sea contained the same 4- to 6-nucleated PAH' s as were 

 identified in the Bering Sea (Table 2) (wt %): BaA plus Chr, 

 16.4; BkF, 1.6; BaP, 2.2; BeP, 8.5; BbF, 0.33; and P was 

 qualitatively identified. However, among the PAH's, 

 dibenz(a)anthracene |DBA] prevailed, whose concentration 

 reached 7 1 %. In the surface layer, BaA and Chr predominated, 

 their concentration reaching 69% of the total PAH concentration, 

 that of BbF was 20%. At deeper horizons, as a rule — BbF and 

 BaP in the suspended matter averaged 30% of the total PAH's. 

 Thus, the suspended matter of the Bering and Chukchi Seas 

 contained a wide range of 4-6-nucleated PAH's. The 

 composition and ratio of PAH's differed depending on depth 

 and sampling area. 



PAH's in Biota 



The concentration of PAH's in the biota, as in the other 

 elements of the ecosystem of the Bering and Chukchi Seas, is 

 low, generally below the sensitivity of HPLC. The BaP 



TABLE 4 



PAH content in the suspension ( ne/g I of the Bering ( 1 ) and Chukchi ( 2 ) Seas 

 (47th cruise of the R/V Akadeinik Korolev. July-November 1988). 



Py 



BaA+ 

 Chr 



BPer 



BkF 



BbF 



BaP 



BeP 



DBA 



TABLE 5 



Concentration of BaP (ng/i) in surface 1 1 ) and boundary bottom (2) 



water layers of the Bering Sea, the Bering Strait and the 



Chukchi Sea (August 1988). 



Object 



Plankton 



Zooplankton 



Neuston 



Number of min average standard 

 Points max dev. 



0.4-10.6 3.0 



0.5-8.4 2.2 



up to 10.0 2.6 



Number of min average standard 

 Points max dev. 



2.9 

 2.4 

 3.0 



10 0.22-12.6 

 7 0.6-1.9 



2.8 

 2.0 



3.9 



2.6 



.^(15 



