Physical and Biological Factors Affecting Mercury and Perfluorinated Contaminants in Arctic Char (Salvelinus alpinus) of Pingualuit Crater Lake (Nunavik, Canada)

• Published in: Arctic 2012-06, Vol.65 (2), p.S1
• Main Authors: Gantner, Nikolaus, Veillette, Julie, Michaud, Wendy K, Bajno, Robert, Muir, Derek, Vincent, Warwick F, Power, Michael, Dixon, Brian, Reist, James D, Hausmann, Sonja, Pienitz, Reinhard
• Format: Article
• Language: English
• Subjects: Anthropogenic factors; Arctic environments; Catchments; Chemical contaminants; Contaminants; Cosmetics; Degradation products; Dry deposition; Emissions; Fish; Food packaging; Food webs; Grease; Human populations; Industrial areas; Lakes; Local population; Mercury; Methylmercury; Microbial activity; Predators; Traditional foods; Trophic levels; Wildlife
• ISSN: 0004-0843; 1923-1245

In the Arctic, concentrations of the neurotoxic form of mercury (Hg), methylmercury, in aquatic, marine, and terrestrial apex predators often exceed consumption guidelines for humans (WHO or Health Canada), posing risk to local populations that harvest these traditional food items (AMAP, 2009). The majority of anthropogenic mercury in the Arctic environment is considered to originate from emissions in industrialized areas to the south, particularly from Eurasia (Pacyna et al., 2006). Atmospheric transfer is facilitated by the long atmospheric residence time of mercury (up to 1.5 years) (Lindberg et al., 2007). Arctic lakes receive Hg through wet and dry deposition, as well as runofffrom the surrounding catchments ([DEREK MUIR] et al., 2009; Gantner et al., 2010). Anthropogenic emissions have doubled the background concentrations of Hg in northern Quebec lakes (Muir et al., 2009). Once in lakes, Hg is methylated by microbial communities in sediments and anoxic lake bottom waters, and it enters the food web, where it is biomagnified along trophic levels. Catchments can also influence Hg concentrations in char; large catchments surrounding small lakes yield greater Hg concentrations in char (Gantner et al., 2010). Lake Pingualuk, widely lacking this catchment influence, represents a unique opportunity to determine anthropogenic Hg concentrations in arctic char, which (theoretically) must originate solely from atmospheric deposition to the lake itself. Perfluorinated chemicals have been detected worldwide in humans, in wildlife, and in the global environment, including remote locations such as the High Arctic (Martin et al., 2004; Houde et al., 2006; Stock et al., 2007; [Young, C.J.] et al., 2007). These persistent, human-made substances have been used over the last 50 years in an array of industrial and commercial products such as cosmetics, and water and grease repellent coatings for fabrics and food packaging (e.g., 3M: "Scotch Gard", DuPont: "Zonyl") (Kissa, 2001). However, unlike legacy POPs that accumulate in lipid-rich tissues, PFCs bind to blood proteins and are found mainly in the liver, kidneys, and bile secretions. The two most widely studied PFCs globally have an eightcarbon backbone: perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS ). Both PFOS and PFOA are the final degradation products of volatile precursors that are subject to long-range atmospheric transport to the Arctic (Table 1; Stock et al., 2007; Young et al., 2007). An alter