Aguilar A, Borrell A
Department of Animal Biology (Vertebrates), Faculty of Biology, University of Barcelona, Spain.
Sci Total Environ. 1994 Sep 16;154(2-3):237-47. doi: 10.1016/0048-9697(94)90091-4.
PCB concentrations and total lipid content were determined in the blubber and liver of striped dolphins affected by the 1990 morbillivirus epizootic in the Mediterranean Sea, and in the blubber of striped dolphins from the same area sampled with a biopsy dart in 1987-1989 and 1991. PCB levels were found to be significantly higher in the individuals that succumbed to the epizootic than in the 'healthy' population sampled before or after the event. Although recent mobilization of lipid reserves was found to have occurred in some of the diseased dolphins, this had little effect on their PCB blubber concentrations and cannot explain the observed difference with the healthy individuals. Three hypotheses are put forward to explain the apparent link between high PCB levels and mortality caused by the epizootic: (i) depressed immunocompetence caused by PCBs leading to an increase in individual susceptibility to the morbillivirus infection, (ii) mobilization of fat reserves leading to increased PCB levels in blood which, in turn, may produce a liver lesion capable of increasing the individual's susceptibility to the morbillivirus infection, and (iii) previous existence of an unspecific hepatic lesion producing impairment of the liver function which, in turn, could lead to an increase both in tissue PCB concentrations and in individual susceptibility to the morbillivirus infection.
对受1990年地中海地区麻疹病毒 epizootic影响的条纹原海豚的鲸脂和肝脏，以及1987 - 1989年和1991年用活检镖从同一地区采集的条纹原海豚的鲸脂，测定了多氯联苯（PCB）浓度和总脂质含量。结果发现，死于 epizootic的个体中的PCB水平显著高于在该事件之前或之后采样的“健康”群体。尽管在一些患病海豚中发现近期出现了脂质储备的动员，但这对它们鲸脂中的PCB浓度影响很小，无法解释观察到的与健康个体的差异。提出了三个假说来解释高PCB水平与 epizootic导致的死亡率之间的明显联系：（i）PCB导致免疫能力下降，从而增加个体对麻疹病毒感染的易感性；（ii）脂肪储备的动员导致血液中PCB水平升高，进而可能产生一种肝脏病变，增加个体对麻疹病毒感染的易感性；（iii）先前存在一种非特异性肝脏病变，导致肝功能受损，进而可能导致组织中PCB浓度升高以及个体对麻疹病毒感染的易感性增加。
