Hall Ailsa J, Thomas Gareth O
Sea Mammal Research Unit, Gatty Marine Laboratory, University of St. Andrews, St. Andrews, Fife KY18 8LB, United Kingdom.
Environ Toxicol Chem. 2007 May;26(5):851-61. doi: 10.1897/06-310r.1.
Polychlorinated biphenyls, DDT and its metabolites, polybrominated diphenyl ethers, and selected organochlorine pesticide concentrations were measured in blubber samples from 60 free-living harbor seals in 2003 from five sites around the United Kingdom coast. Significant regional differences among contaminant levels were found, with seals on Islay and Jura (southwest Scotland) having the highest levels of polychlorinated biphenyls and seals in the Wash (eastern England) having the highest polybrominated diphenyl ether levels. Animals from the north and northeast of Scotland (Orkney and the Moray Firth) had the lowest levels of all the contaminant groups studied. Congener-specific profiles of polychlorinated biphenyls and polybrominated diphenyl ethers showed relatively higher levels of the lower chlorinated and brominated compounds at the more northerly sites, with the lowest total levels of both chemical groups. Significant positive relationships between blubber contaminants and total triiodothyronine (TT3) concentrations were found after controlling for the potential effects of confounding because of sex, mass, and season. Increased serum TT3 levels were significantly related to higher blubber contaminant concentrations in the following order: sum of all contaminants > polybrominated diphenyl ethers > polychlorinated biphenyls > DDT. Serum TT3 levels in the harbor seals with the highest exposures might be indicative of a T3 thyrotoxicosis, but without information on free T3 and circulating thyroid-stimulating hormone levels, it is difficult to determine the importance of this observation for the health of the individuals or populations. However, the mixture of contaminants to which United Kingdom harbor seals are exposed has changed over the last few decades, and the toxicological and epidemiological importance of adding the brominated compounds to the classical organochlorine and heavy metal mixture is not known.
2003年，在英国海岸周围五个地点采集了60只自由生活的港海豹的脂肪样本，检测了其中多氯联苯、滴滴涕及其代谢产物、多溴二苯醚和选定的有机氯农药的浓度。研究发现污染物水平存在显著的区域差异，艾莱岛和朱拉岛（苏格兰西南部）的海豹体内多氯联苯水平最高，沃什湾（英格兰东部）的海豹体内多溴二苯醚水平最高。苏格兰北部和东北部（奥克尼群岛和莫雷湾）的动物体内所有研究的污染物组水平最低。多氯联苯和多溴二苯醚的同系物谱显示，在更偏北的地点，较低氯化和溴化化合物的水平相对较高，而这两类化学物质的总水平最低。在控制了性别、体重和季节等混杂因素的潜在影响后，发现脂肪污染物与总三碘甲状腺原氨酸（TT3）浓度之间存在显著的正相关关系。血清TT3水平升高与脂肪污染物浓度升高显著相关，顺序如下：所有污染物总和>多溴二苯醚>多氯联苯>滴滴涕。暴露水平最高的港海豹的血清TT3水平可能表明存在T3甲状腺毒症，但由于缺乏游离T3和循环甲状腺刺激激素水平的信息，很难确定这一观察结果对个体或种群健康的重要性。然而，在过去几十年里，英国港海豹接触的污染物混合物发生了变化，将溴化化合物添加到经典有机氯和重金属混合物中的毒理学和流行病学重要性尚不清楚。
