Mercury biomagnification in freshwater ecosystems of Nova Scotia

Abstract

Mercury (Hg) biomagnifies consistently in aquatic food webs around the world. This can be a human health concern in areas with recreational and subsistence fisheries, as the main biomagnifying agent (methylmercury), is a potent neurotoxin. My objective was to assess mercury biomagnification rates in freshwater ecosystems across Nova Scotia and provide data on potential Hg risk in freshwater based on environmental parameters. Trophic magnification slope factors and intercepts varied significantly among the 21 waterbodies examined (TMS; 0.021 - 0.423). Potential bioavailable Hg in freshwater, calculated using water quality data (chlorophyll-a, phosphorus, total organic carbon, and pH) and percent wetland cover, showed that Hg risk varied across the province.