Mercury Accumulation in Harbour Seals from the Northeastern Pacific Ocean: The Role of Transplacental Transfer, Lactation, Age and Location.

摘要: Mercury (Hg) bioaccumulates in the aquatic food chain form of methylmercury, a compound well known for its neurotoxicity. We analyzed total mercury (THg) hair collected from 209 harbour seals captured at 10 sites British Columbia (Canada) and Washington State (USA) between 2003 2010. In addition, laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) allowed highly refined analysis THg accumulation over time by examining nine whiskers taken 4- to 6-week-old pups. estimate that concentrations pups increased sharply point corresponding mid- late gestation their utero (4.7 ± 0.8 6.6 1.3 µg/g dry weight (dw), respectively), then again onset nursing (8.1 dw). These abrupt changes highlight importance both pre- post-natal transfer mother growing fetus newborn pup. While levels varied among sites, analyses same site demonstrated influence age with (5.3 0.3 µg/g) juveniles (4.5 0.5 having lower than those adults (8.3 µg/g). Our results revealed 33 % sampled (n = 167) had surpassed mammalian threshold neurochemical alterations. This study suggests Hg could represent health concern marine wildlife, especially as atmospheric emissions this toxic element human activities Pacific Rim worldwide continue.