Although more than ten years have already passed since the May 2004 effectuation of Stockholm Convention on Persistent Organic Pollutants (POPs), POPs are still present in the environment and high trophic-level wild animals, such as marine mammals, accumulate elevated levels of these environmental contaminants. Our study group has been conducting temporal trend analyses of POPs pollution using sediment core samples and archived blubber samples of marine mammals stored in the Environmental Specimen Bank (
es-BANK) of Ehime University. Our results showed that concentrations of POPs registered on the effectuation date (May 2004) tended to decrease since the 1970s, but those of brominated flame retardants,
i.e., polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs), registered after 2009 (new POPs) clearly increased. Especially, levels of PBDEs and HBCDs in the pelagic whale species were steady-state or increased even since 2000, indicating a continuous transportation of these new POPs into the oceanic region. Development of an international monitoring network including developing regions for global and local POPs pollution in the environment and various wildlife species is needed to verify the effect of POPs regulation.
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