Department of Chemistry and CESAM, University of Aveiro, 3810-193, Aveiro, Portugal; Pelagic Ecology Research Group, Scottish Oceans Institute, University of St Andrews, St Andrews, KY16 8LB, UK.
British Antarctic Survey, NERC, High Cross, Madingley Road, CB30ET, Cambridge, UK; MARE-Marine and Environmental Sciences Centre, Department of Life Sciences, University of Coimbra, 3000-456, Coimbra, Portugal.
Environ Pollut. 2019 Apr;247:332-339. doi: 10.1016/j.envpol.2019.01.031. Epub 2019 Jan 14.
Total and organic mercury concentrations were determined for males, females and juveniles of Euphausia superba collected at three discrete locations in the Scotia Sea (South Orkney Islands, South Georgia and Antarctic Polar Front) to assess spatial mercury variability in Antarctic krill. There was clear geographic differentiation in mercury concentrations, with specimens from the South Orkney Islands having total mercury concentrations 5 to 7 times higher than Antarctic krill from South Georgia and the Antarctic Polar Front. Mercury did not appear to accumulate with life-stage since juveniles had higher concentrations of total mercury (0.071 μg g from South Orkney Islands; 0.014 μg g from South Georgia) than adults (0.054 μg g in females and 0.048 μg g in males from South Orkney Islands; 0.006 μg g in females and 0.007 μg g in males from South Georgia). Results suggest that females may use egg laying as a mechanism to excrete mercury, with eggs having higher concentrations than the corresponding somatic tissue. Organic mercury makes up a minor percentage of total mercury (15-37%) with the percentage being greater in adults than in juveniles. When compared to euphausiids from other parts of the world, the concentration of mercury in Antarctic krill is within the same range, or higher, highlighting the global distribution of this contaminant. Given the high potential for biomagnification of mercury through food webs, concentrations in Antarctic krill may have deleterious effects on long-lived Antarctic krill predators.
在斯科舍海（南奥克尼群岛、南乔治亚岛和南极极锋）的三个不同地点采集了磷虾属（Euphausia superba）的雄性、雌性和幼体，以评估南极磷虾中汞的空间变异性。汞浓度存在明显的地域差异，南奥克尼群岛的样本总汞浓度比南乔治亚岛和南极极锋的南极磷虾高 5 至 7 倍。汞似乎没有随着生命阶段而积累，因为幼体的总汞浓度更高（南奥克尼群岛的 0.071μg/g；南乔治亚岛的 0.014μg/g）高于成体（南奥克尼群岛的 0.054μg/g 在女性中；0.048μg/g 在男性中；南乔治亚岛的 0.006μg/g 在女性中；0.007μg/g 在男性中）。结果表明，雌性可能会利用产卵作为排泄汞的机制，其卵中的汞浓度高于相应的体组织。有机汞占总汞的比例较小（15-37%），而成体中的比例高于幼体。与来自世界其他地区的磷虾相比，南极磷虾中的汞浓度处于相同范围内，或更高，突显了这种污染物的全球分布。鉴于汞通过食物网高度生物放大的潜力，南极磷虾中的浓度可能对寿命长的南极磷虾捕食者产生有害影响。
