Abstracts of the 2019 Annual Conference of the International Society for Environmental Epidemiology, August 25-28 2019, Utrecht, the Netherlands
Total Mercury Concentrations in Freshwater Fish & Riverine Sediment in Suriname, South America
TPS 621: Exposure to metals, Johan Friso Foyer, Floor 1, August 26, 2019, 3:00 PM - 4:30 PM
This study focuses on comparing total mercury concentrations, between 2017 and 2018, in fish and sediment samples of rivers in the lowlands of Central and Western Suriname. The use of mercury, as an amalgamation agent, in the artisanal and small scale gold mining (ASGM) industry has resulted in the release of this heavy metal into the environment. Previous studies have shown that mercury accumulates in areas downstream and downwind of ASGM activities. Subsequently, anaerobic bacteria will convert mercury into methylmercury, a highly neurotoxic organic compound. Climate variables (such as temperature, rainfall) and water quality parameters (pH, temperature, conductivity, dissolved oxygen content, etc.) influence the rate and amount of methylation. In fish, methylmercury accounts for approximately 83% of total mercury concentrations. This ongoing research, which started in October 2017, assessed total mercury concentrations in fish tissue and riverine sediment samples at seven locations close to communities that incorporate fish into their diet. Sampling took place in both a cool and a warm period of the year. In addition to fish and sediment sampling, water quality measurements at each location were taken. For both fish and sediment, sampling was conducted in duplicate. Total mercury concentrations in fish ranged from 0.01 ug/g to 1.01 ug/g between sites, with one site (Pikien Saron) consisting of more than 50% of sampled fish above the EPA screening level of 0.3 ug/g. Total mercury concentrations in sediment ranged from 0.02 ug/g to 0.24 ug/g. For sediment there is a Threshold Effect Level (TEL) of 0.17 ug/g total mercury concentration. At or below this level rarely results in adverse biological effects. For the sampling site of Pikien Saron, all sediment samples were above the TEL. Ultimately, these data will support future health risk assessments with regards to the exposure of local communities to methylmercury by consuming fish.Copyright © 2019 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of Environmental Epidemiology. All rights reserved.