Assessing correlations between monomethylmercury accumulation in fish and trophic states of artificial temperate reservoirs

Abstract

We investigated monomethylmercury (MMHg) concentrations in 448 samples of four common fish species (barbel steed, largemouth bass, leopard mandarin, and bluegill) and the trophic states of 14 artificial reservoirs in South Korea in order to understand how trophic states of reserviors affect MMHg concentrations in fish. The trophic state index (TSI) of each reservoir was determined usingampirical equations based on the monthly chlorophyll-a, total phosphorus, and Secchi depth, collected over a three-year period. The length-normalized MMHg concentrations in fish showed a negative correlation with the TSI based on chlorophyll-a (r(2) = 0.90) and total phosphorus (r(2) = 0.75) that may be a result of particle dilution of MMHg in surface waters. This study revealed that MMHg accumulation in fish was better correlated with TSI than MMHg in water, therefore, we suggest that the measurement of TSI based on chlorophyll -a and total phosphorus is an effective way to predict MMHg bioaccumulation across diverse reservoirs. (C) 2016 Published by Elsevier B.V.