title: Accumulation features and temporal trends of PCDDs, PCDFs and PCBs in Baikal seals (Pusa sibirica).
abstract: This study investigated the accumulation features and temporal trends of PCDD/Fs, dioxin-like PCBs (DL-PCBs) and non-dioxin-like PCBs (NDL-PCBs) in the blubber of Baikal seals collected in 1992 and 2005. DL-PCBs (480-3600ng/g) and NDL-PCBs (980-35,000ng/g) were dominant contaminants. Concentrations of PCDDs and PCBs in males were significantly higher than in females. In males, age-dependent accumulation was observed for PCDDs, mono-ortho PCBs and NDL-PCBs. PCDFs and non-ortho PCBs showed no such trends, implying that exposure of seals to these contaminants has been decreasing in recent years. No decreasing temporal trend was observed for PCDDs, mono-ortho PCBs and NDL-PCBs, suggesting that Baikal seals are still exposed to PCDDs and PCBs. TEQs of PCDDs and mono-ortho PCBs in seals collected in 2005 accounted for 62-77% of total TEQs. The TEQ levels in 40% of the specimens exceeded the threshold level for immunosuppression observed in harbor seals (209pg/g).
authors.affiliation: Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Imaeda
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kunisue
authors.forename: Yoko
authors.initials: Y
authors.lastname: Ochi
authors.forename: Hisato
authors.initials: H
authors.lastname: Iwata
authors.forename: Oyuna
authors.initials: O
authors.lastname: Tsydenova
authors.forename: Shin
authors.initials: S
authors.lastname: Takahashi
authors.forename: Masao
authors.initials: M
authors.lastname: Amano
authors.forename: Evgeny A
authors.initials: EA
authors.lastname: Petrov
authors.forename: Valeriy B
authors.initials: VB
authors.lastname: Batoev
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Tanabe
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry* / Q000378:metabolism; D000818:Animals; D001822:Body Burden; D054750:Ecotoxicology / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis* / Q000493:pharmacokinetics; D005260:Female; D005618:Fresh Water; D008297:Male; D011078:Polychlorinated Biphenyls / Q000032:analysis* / Q000493:pharmacokinetics; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis / Q000493:pharmacokinetics; D046048:Seals, Earless / Q000378:metabolism*; D012800:Siberia; D013997:Time Factors
chemical_list: D004785:Environmental Pollutants; D000072317:Polychlorinated Dibenzodioxins; D011078:Polychlorinated Biphenyls