Neale J C C, Gulland F M D, Schmelzer K R, Harvey J T, Berg E A, Allen S G, Greig D J, Grigg E K, Tjeerdema R S
Department of Environmental Toxicology, University of California at Davis, Davis, California 95616, USA.
J Toxicol Environ Health A. 2005 Apr 23;68(8):617-33. doi: 10.1080/15287390590921748.
An expanding body of research indicates that exposure to contaminants may impact marine mammal health, thus possibly contributing to population declines. The harbor seal population of the San Francisco Bay (SFB), California, has suffered habitat loss and degradation, including decades of environmental contamination. To explore the possibility of contaminant-induced health alterations in this population, blood levels of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs) were quantified in free-ranging seals; relationships between contaminant exposure and several key hematological parameters were examined; and PCB levels in the present study were compared with levels determined in SFB seals a decade earlier. PCB residues in harbor seal blood decreased during the past decade, but remained at levels great enough that adverse reproductive and immunological effects might be expected. Main results included a positive association between leukocyte counts and PBDEs, PCBs, and DDE in seals, and an inverse relationship between red blood cell count and PBDEs. Although not necessarily pathologic, these responses may serve as sentinel indications of contaminant-induced alterations in harbor seals of SFB, which, in individuals with relatively high contaminant burdens, might include increased rates of infection and anemia.
越来越多的研究表明，接触污染物可能会影响海洋哺乳动物的健康，从而可能导致其种群数量下降。加利福尼亚州旧金山湾（SFB）的斑海豹种群遭受了栖息地丧失和退化，包括数十年的环境污染。为了探究该种群中污染物导致健康改变的可能性，对自由放养海豹的血液中多氯联苯（PCBs）、二氯二苯二氯乙烯（DDE）和多溴二苯醚（PBDEs）的水平进行了定量；研究了污染物暴露与几个关键血液学参数之间的关系；并将本研究中的PCB水平与十年前在SFB海豹中测定的水平进行了比较。在过去十年中，斑海豹血液中的PCB残留量有所下降，但仍处于足以预期产生不良生殖和免疫影响的水平。主要结果包括海豹体内白细胞计数与PBDEs、PCBs和DDE之间呈正相关，红细胞计数与PBDEs之间呈负相关。尽管这些反应不一定是病理性的，但它们可能是SFB斑海豹中污染物引起改变的哨兵指标，在污染物负荷相对较高的个体中，可能包括感染率和贫血率增加。
