dried at room temperature. A quantitative determination of 

 BaP was performed using the spectral-luminescence methods 

 based on the measurement of the relative intensity of the 

 luminescence of the BaP solution in n-octane and using 

 benzo(ghi)perylene (BPer) as an internal standard, which was 

 frozen at -196°C, (Shpolshy effect- [Fedoseyeva and Khesina, 

 1968]). 



A quantitative determination of the other PAH's was 

 carried out using high-performance liquid chromatography 

 ( HPLC). A mixture of PAH" s similar in composition to known 

 environmental pollutants served as standards [US NIST 

 Standard Reference Material, SRM-1647a|. The determination 

 of the PAH"s was carried out starting with pyrene. which was 

 the first to elute from the column. 



Conditions of Analysis 



Dry samples were dissolved in 0.2 ml of acetonitrile and 

 introduced into a "Knauer" liquid chromatograph equipped 

 with a 'Kratos' fluorescence detector. The excitation and 

 emissions wavelengths were 295 nm and 418 nm; the eluent 

 solution was 95% methanol in water at a flow-rate of 

 0.5 ml/min through a (25 x 0.25-cm) 'Perkin Elmer' Sil ODS 

 column. The absolute calibration method was used for the 

 determination. The sensitivity was 10'' g. 



Results and Discussion 



In the water, sediments, suspended matter, and biota of the 

 Bering and Chukchi Seas, 10 PAH's were identified, of which 

 eight are carcinogenic and three of these (viz., 

 benzo(b)fluoranthene [BbF|, benzo(k)fluoranthene [BkF] and 

 BaP) are highly carcinogenic (Table 1). 



PAH's in Water 



In the Bering Sea and the Bering Strait, the PAH 

 concentration in water was below the sensitivity of the HPLC 

 method. In the northwestern Bering Sea and eastward from 

 St. Lawrence Island, the surface and near-bottom water 

 contained a high concentration of PAH's (from 0.5 to 

 149.2 ng/1) which were made up of seven representatives of 

 four- and five-nucleated PAH's (Table 2). In the surface layer 

 the following compounds prevailed (wt. %): benzo(e)pyrene 

 [BeP] 40.3, pyrene [P] 35.14; the concentration of other 

 PAH's was as follows: BbF, 17.6: BaP, 4.76; and BkF, 2.2%. 

 In the near-bottom layer, the distribution of PAH's was 

 the following: BeP, 47.43: benz(a)anthracene [BaA] and 

 chrysene [Chr], 40.4; Py, 7.67; BbF, 2.7; BaP, 1.9: and 

 BkF, 0.2. 



Thus, the concentration of PAH's in surface and near- 

 bottom layers differed. In the water of the central, southern, 

 and partly northeastern areas of the Bering Sea and the Bering 

 Strait, insignificant amounts of BaP were detected (Table 3), 

 not exceeding the background level. In most cases, the PAH 

 concentration in the surt'ace water layer was twice as high as 

 that in the near-bottom layer. While in the central part of the 

 Bering Sea (Fig. 2), the BaP concentration increased 10-fold 

 from the top to the bottom (e.g.. Station 6 increased from 

 0.1 ng/1 at the surface to 1.02 ng/1 in the deepest sample). 



Table 1 



List ol specific PAH's identified by displacement-elutional liquid chromatography 



Name Symbol Structural formula 



Carcinogenicity 

 (Lee«u/, \VH\) 



Pyrene 



Chrysene 



Ben/(a)anlhracene 



Bcn/otelpyrene 



Ben/oihlfluoranthenc 



oS^ 



BaA 



BbF 



oc6^ 



Benzolkitluoranthene BkF 



Benzotalpyrene BaP 



Benzotg.h.ilperylene BPer 



Dibenzta.hlanthraccnc DBA 



Indeno(l,2,.^-cd)pyrene IPy 



Note 

 Classification 



noncarcinogenic 

 weakly carcinogenic 

 strongly carcinogenic 



Symbol 

 



Criterion: % of animals 



that developed lesions 

 

 33 

 >33 



According to our data the total concentration of PAH's in the 

 SML in that same area was also below the sensitivity of HPLC, 

 but the concentration of BaP ( Fig. 3 ) is x3 as high as that in the 

 surface layer; however, they did not exceed the values 

 established for SML in the other oceanic environments 

 (Anikejev&Urbanovitch, 1989). The concentration of PAH's 

 in the Chukchi Sea waters was also often below the sensitivity 

 of HPLC method. In the water of the southeastern part of this 

 sea, the same 4- to 5-nucleated PAH's were identified as in the 

 Bering Sea (Table 2): Py, BaA, Chr, BeP. BkF, BaP. Their 

 overall concentration in the surface water layers did not exceed 

 5. 1 ng/1, but in the near-bottom layer it reached 24 ng/1, which 

 is considerably lower than the respective values for the Bering 

 Sea. Five-nucleated PAH" s accounted for the major portion of 

 the total concentration of PAH in the surface layer ( wt % ): BeP, 

 72; BbF, 28. Benzo(a)pyrene, BaA, and Chr were present in 

 trace amounts and the near-bottom layer was characterized by 

 the following pattern: BeP, BbF, and BaP which accounted for 

 72, 23, and 5%, respectively. Benzo(a)anthracene and BkF 

 were present in trace amounts. The abundance of BaP in the 

 surt'ace water layers in the Chukchi Sea area, where the level of 

 PAH was below the sensitivity of HPLC. was also insignificant 

 being lower than for the Bering Sea (Table 3). However, in the 

 near-bottom layers of both seas, its level was the same. It 

 should be mentioned that the concentration of BaP in ice 

 samples was somewhat higher than in the surface water layers 

 (Fig. 4) and it increased with depth. 



302 



