Mercury Biomagnification in Marine Zooplankton Food Webs in Hudson Bay

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• 作者：Karen L. Foster ; Gary A. Stern ; Monica A. Pazerniuk ; Brendan Hickie ; Wojciech Walkusz ; Feiyue Wang ; Robie W. Macdonald
• 刊名：Environmental Science & Technology (ES&T)
• 出版年：2012
• 出版时间：December 4, 2012
• 年：2012
• 卷：46
• 期：23
• 页码：12952-12959
• 全文大小：402K
• 年卷期：v.46,no.23(December 4, 2012)
• ISSN：1520-5851

文摘

While much research has been carried out on mercury in large marine mammals and associated food webs in northern regions, comparatively less has been conducted on lower trophic levels including zooplankton and the subsequent transfer to predators, which marks the entry of mercury into northern marine food webs. We present here the first database for mercury uptake and transfer exclusively within zooplankton food webs in northern marine waters. We have investigated both total (THg) and monomethylmercury (MMHg) concentrations, and isotopic signatures (未¹⁵N and 未¹³C) in individual zooplankton taxa collected over a period of eight years (2003鈥?010) from across Hudson Bay (including Hudson Strait and Foxe Basin) as part of research icebreaker cruises. 未¹⁵N values ranged from 3.4 to 14.0鈥? implying trophic levels ranging from 1 to 4, and THg concentrations ranged from 5 to 242 ng g^鈥? dw. Food web linkages were identified within the data set, and mercury biomagnification was evident both with THg and MMHg concentrations increasing from prey to predator, and with trophic magnification factors (TMFs). Total mercury and MMHg transfer in a unique prey鈥損redator linkage (Limacina helicina鈥揅lione limacina) are investigated and discussed with regard to known physiological and biochemical characteristics. The results suggest that exposure to mercury at higher trophic levels including humans can be affected by processes at the bottom of Arctic marine food webs.