Persistent organic pollutants in ringed seals from the Russian Arctic

Area of Science:

• Environmental Science
• Ecotoxicology
• Arctic Research

Background:

• Persistent organic pollutants (POPs) accumulate in Arctic marine mammals.
• Ringed seals are key indicators of Arctic ecosystem health.
• Understanding contaminant distribution is crucial for conservation.

Purpose of the Study:

• To analyze organochlorine compounds (DDT, HCH, PCBs, PBDEs, etc.) in Russian Arctic ringed seals.
• To compare contamination levels across different Russian Arctic regions.
• To assess seal contamination relative to other Arctic populations.

Main Methods:

• Blubber samples from adult ringed seals (2001-2005).
• Analysis of total DDT (ΣDDT), HCH isomers (ΣHCH), toxaphenes, mirex, endrin, methoxychlor, chlorinated benzenes (ΣCBz), chlordane compounds (ΣCHL), PCBs (56 congeners; ΣPCBs), PCDD/Fs, and PBDEs (7 congeners; ΣPBDEs).
• Geographical comparison of contaminant levels.

Main Results:

• Kara Sea seals (Dikson Island) showed highest ΣDDT, ΣPCBs, ΣCHL, and mirex.
• Chukchi Sea seals had highest ΣHCHs; White Sea seals had highest PCDD/Fs.
• European Russian Arctic seals had higher ΣDDT and ΣPCBs than other Arctic regions; other organochlorines were similar or lower.
• ΣPBDEs were widespread, with Chukchi Sea seals having significantly lower levels.

Conclusions:

• Geographic variation in POPs contamination exists within the Russian Arctic ringed seal population.
• Ringed seals in the Kara Sea and Chukchi Sea face distinct contaminant burdens.
• Russian Arctic seal contamination levels for most compounds are comparable to or lower than other Arctic regions, except for ΣDDT and ΣPCBs.