Analysis of organochlorine compounds and extractable organic halogen in three subspecies of ringed seal from Northeast Europe

Abstract

Oganochlorine compounds in blubber samples of the ringed seal (Phoca hispida saimensis, P. h. ladogensis, and P. h. hispida) were analyzed in order to estimate the state of pollution in three different water areas in Northeast Europe, namely, Lake Saimaa in Finland, Lake Ladoga, and the White Sea in Russia. Geographic differences in concentrations and in relative concentrations of tri‐ and tetrachlorocymenes, hexachlorobenzene, α‐HCH, β‐HCH, ‐γ‐HCH (Lindane), seven polychlorinated bi‐phenyl (PCB) congeners, and p,p′‐DDT and its metabolites in ringed seals were compared. Concentrations of chlorinated hydrocarbons varied between the water areas. The highest concentrations were found in Saimaa ringed seals, followed by Ladoga ringed seals, and the lowest concentrations were detected in ringed seals from the White Sea. Extractable organic halogen (EOX) concentrations in blubber were also analyzed. The concentrations showed a geographic trend similar to those for the individual compounds identified. In Lakes Ladoga and Saimaa, the concentrations of EOX and chlorinated hydrocarbons in the blubber were dependent on the age and sex of the seals, but no such relationship was observed in samples from the White Sea.

Organochlorine concentrations in the saimaa ringed seal (Phoca hispida saimensis) from Lake Haukivesi, Finland, 1981 to 2000, and in its diet today

“…However, that phenomenon is not general. In a previous study of ringed seals from Lake Ladoga and Lake Saimaa, β‐HCH was the most abundant form from 1988 to 1995, indicating persistence of this isomer [25]. The termination of use of HCHs in the Lake Saimaa area also is evident from to this study, because only β‐HCH and some traces of lindane were present in ringed seals from the late 1990s.…”

“…The proportions of HCHs to ∑HCH in Lake Haukivesi ringed seals that died during the 1980s are similar to those of technical HCH, in which the proportions are 60 to 70% of α‐HCH, 5 to 12% of β‐HCH, and 10 to 15% of lindane [42], except that the proportion of β‐HCH was higher in this study. Many studies have shown the high ratio of α‐HCH in Arctic waters, mainly because of long‐range transport of that isomer [9,25,32,42]. However, that phenomenon is not general.…”

“…The ringed seal blubber samples were homogenized with acetone:hexane (7:2, v/v) and reextracted with hexane:diethylether (9:1, v/v). More detailed methods and information about the chemicals and standards that were used are reported by Kostamo et al [23,25]. For the OCl analysis, a Hewlett‐Packard 6890 gas chromatograph with a mass selective detector (Hewlett‐Packard, Avondale, PA, USA) in selected ion monitoring mode and a 7673 autosampler was used as described by Kostamo et al [25].…”

“…More detailed methods and information about the chemicals and standards that were used are reported by Kostamo et al [23,25]. For the OCl analysis, a Hewlett‐Packard 6890 gas chromatograph with a mass selective detector (Hewlett‐Packard, Avondale, PA, USA) in selected ion monitoring mode and a 7673 autosampler was used as described by Kostamo et al [25]. Total concentrations of PCBs (∑PCB7) were calculated as the sum of the seven congeners (International Union of Pure and Applied Chemisty numbers 28, 52, 101, 118, 138, 153, and 180) that were found to represent 32.9% of Aroclor 1260.…”

“…Extractable organic halogen (EOX) is a sum parameter for halogenated compounds, and has been used in estimation of quantities of OCls discharged from the pulp and paper industry [21,22]. Previously, EOX was analyzed in fish and mussels [21–23], but only few studies have reported concentrations in marine mammals [23–25]. The EOX parameter is not unambiquous.…”