Dep. of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, Denton, TX 76201, USA.
Dep. of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, Denton, TX 76201, USA.
Mar Environ Res. 2018 Jul;138:96-101. doi: 10.1016/j.marenvres.2018.04.008. Epub 2018 Apr 22.
Polybrominated diphenyl ethers (PBDEs) are highly lipophilic components of brominated flame retardants that are environmentally persistent and bioaccumulate. PBDEs are taken up from the gastrointestinal tract and accumulate mainly in fat depots and liver tissues. Seal species inhabiting Arctic and sub-Arctic regions can have upwards of 30% of their body mass composed of blubber. When those blubber stores are mobilized for energy, stored toxicants are also released into circulation. Most studies reporting accumulation of PBDEs in seals have focused on harbor and grey seals with few examining harp and hooded seals. In this study, PBDEs concentrations were analyzed in seal blubber from 21 stranded harp and 9 stranded hooded seals sampled along the northeast coast of the U.S. (1999-2010). A PBDE congener profile was determined for each individual. The results show that both species of seals are accumulating PBDEs with BDE-47 being the dominant congener. Mean ƩPBDE concentrations in harp seals were 70.55 ± 33.59 ng/g ww and for hooded seals 94.28 ± 42.65 ng/g ww. The results of this study are consistent with previous studies reporting a decrease in bioaccumulation with an increase in bromination. For both species, BDE-47 represented the highest percentage of the ƩPBDEs, composing over 50% of the ƩPBDEs in harp seals. When compared to stranding condition code, animals found alive had overall higher PBDE concentrations than those found in a state of moderate decomposition. This difference could be due to decreased blubber levels in the decomposed animals or potential degradation of the compounds in the blubber. Almost all seals used in this study were yearlings which is the most likely age class to strand. Yearling seals are at a crucial stage of development, especially of their immune system, which can be impacted by high levels of contaminants like PBDEs and increase the susceptibility to disease.
多溴二苯醚（PBDEs）是溴化阻燃剂中高度亲脂性的成分，具有环境持久性和生物累积性。PBDEs 可从胃肠道吸收，并主要积聚在脂肪组织和肝脏组织中。栖息在北极和亚北极地区的海豹物种的身体质量中有多达 30%是由鲸脂组成的。当这些鲸脂储存被动员用于能量时，储存的有毒物质也会释放到循环系统中。大多数报告海豹体内 PBDEs 积累的研究都集中在港湾海豹和灰海豹上，很少有研究检查竖琴海豹和冠海豹。在这项研究中，分析了在美国东北海岸搁浅的 21 只竖琴海豹和 9 只冠海豹的鲸脂中的 PBDE 浓度（1999-2010 年）。为每个个体确定了 PBDE 同系物谱。结果表明，这两个物种的海豹都在积累 PBDEs，其中 BDE-47 是主要的同系物。竖琴海豹的平均 ΣPBDE 浓度为 70.55±33.59ng/gww，而冠海豹的浓度为 94.28±42.65ng/gww。本研究结果与先前报道的生物累积随溴化程度增加而减少的研究结果一致。对于这两个物种，BDE-47 代表了 ΣPBDEs 的最高百分比，在竖琴海豹的 ΣPBDEs 中占比超过 50%。与搁浅状况代码相比，发现存活的动物的 PBDE 浓度总体高于处于中度分解状态的动物。这种差异可能是由于分解动物的鲸脂水平降低，或鲸脂中化合物的潜在降解。本研究中使用的几乎所有海豹都是一岁龄，这是最有可能搁浅的年龄组。一岁龄的海豹正处于发育的关键阶段，尤其是它们的免疫系统，可能会受到 PBDE 等污染物的高水平影响，并增加患病的易感性。
