The Marine Mammal Center, 2000 Bunker Road, Sausalito, CA 94965, USA.
Sci Total Environ. 2011 Aug 15;409(18):3537-47. doi: 10.1016/j.scitotenv.2011.05.047.
Persistent organic pollutants have been associated with disease susceptibility and decreased immunity in marine mammals. Concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), polybrominated diphenyl ethers (PBDEs), chlordanes (CHLDs), and hexachlorocyclohexane isomers (HCHs) were evaluated in terms of stage of development and likely exposure routes (in utero, suckling, fasting) in the blubber of 202 stranded and wild-caught, primarily young of the year (n=177), harbor seals (Phoca vitulina) in the central California coast. This is the first report of HCH concentrations in the blubber of California seals. Lipid normalized concentrations ranged from 200 to 330,000 ng/g for sum PCBs, 320-1,500,000 ng/g for sum DDTs, 23-63,000 ng/g for sum PBDEs, 29-29,000 ng/g for sum CHLDs, and 2-780 ng/g for sum HCHs. The highest concentrations were observed in harbor seal pups that suckled in the wild and then lost mass during the post-weaning fast. Among the pups sampled in the wild and those released from rehabilitation, there were no differences in mass, blubber depth, or percent lipid although contaminant concentrations were significantly higher in the pups which nursed in the wild. When geographic differences were evaluated in a subset of newborn animals collected near their birth locations, the ratio of sum DDTs to sum PCBs was significantly greater in samples from an area with agricultural inputs (Monterey), than one with industrial inputs (San Francisco Bay). A principal components analysis distinguished between seals from San Francisco Bay and Monterey Bay based on specific PCB and PBDE congeners and DDT metabolites. These data illustrate the important influence of life stage, nutritional status, and location on blubber contaminant levels, and thus the need to consider these factors when interpreting single sample measurements in marine mammals.
持久性有机污染物与海洋哺乳动物的疾病易感性和免疫力下降有关。在加利福尼亚中部海岸搁浅和野生捕获的主要是幼仔（n=177）的 202 只港湾海豹（Phoca vitulina）的鲸脂中，评估了多氯联苯（PCBs）、二氯二苯三氯乙烷及其代谢物（DDTs）、多溴联苯醚（PBDEs）、氯丹（CHLDs）和六氯环己烷异构体（HCHs）的浓度及其发育阶段和可能的暴露途径（宫内、哺乳、禁食）。这是加利福尼亚海豹鲸脂中 HCH 浓度的首次报告。脂标准化浓度范围为 PCBs 总量为 200-330,000ng/g，DDTs 总量为 320-1,500,000ng/g，PBDEs 总量为 23-63,000ng/g，CHLDs 总量为 29-29,000ng/g，HCHs 总量为 2-780ng/g。在野生环境中哺乳并在随后的断奶禁食期间减轻体重的幼海豹中观察到最高浓度。在野生采样的幼海豹和从康复中释放的幼海豹中，体重、鲸脂厚度或脂肪百分比没有差异，尽管在野生哺乳的幼海豹中污染物浓度明显更高。在收集于其出生地点附近的一组新生动物中评估地理差异时，来自农业投入（蒙特雷）地区的样本中，DDTs 总量与 PCBs 总量的比值明显大于来自工业投入（旧金山湾）地区的样本。主成分分析根据特定的 PCB 和 PBDE 同系物以及 DDT 代谢物区分了来自旧金山湾和蒙特雷湾的海豹。这些数据说明了生命阶段、营养状况和位置对鲸脂污染物水平的重要影响，因此在解释海洋哺乳动物的单次样本测量时需要考虑这些因素。
