[Accumulation Characteristics and Health Risk Assessment of Heavy Metals in Wild Fish Species from Diaojiang River, Guangxi].

ABSTRACT

To explore the accumulation characteristics and health risk assessment of heavy metals in wild fish species, the concentrations of heavy metals (Pb, Cd, Cr, As and Hg) in the muscle samples of eight wild fish species collected from Diaojiang River, Guangxi were analyzed. The degree of pollution, food safety and health risk of heavy metals in wild fish species were evaluated using the average pollution index and the target hazard quotient methods. The results showed that the concentrations of Pb, Cd, Cr, As and Hg in wild fish species ranged from 0.041 to 1.160, 0.0001 to 0.066, 0.173 to 0.789, 0.010 to 2.420 and 0.0007 to 0.077mg·kg-1, respectively. The concentrations of Pb and As in wild fish species exceeded the limit values of the Maximum Levels of Contaminants in Foods (GB 2762-2012), and the over-standard rates were 5.06% and 64.56% respectively. The concentrations of Cd, Cr and Hg did not exceed the standard. The average pollution index results showed that Acheilognathus tonkinensis and Acheilognathus barbatus were seriously polluted by heavy metals. The Oreochromis niloticus were moderately polluted. The Siniperca kneri Garman, Carassius auratus, Pseudohemiculter dispar, Ctenopharyngodon idellus, Hemiculter leucisculus were slightly polluted. Higher bioaccumulation factors of Pb, Cr and Hg were found in wild fish species from Diaojiang River. The concentrations of heavy metals in carnivorous fish and omnivorous fish were higher than those in herbivorous fish. Potential health risk assessment showed that the total target hazard quotients (TTHQ) of Acheilognathus tonkinensis and Acheilognathus barbatus were higher than 1. It indicated that the local residents posed higher human health risk due to the long-term consumption of Acheilognathus tonkinensis and Acheilognathus barbatus. Among all the TTHQ in wild fish species (except Pseudohemiculter dispar and Hemiculter leucisculus), the contribution rate of As was the highest, and the average contribution rate reached 76.63%, which indicated that As was the main risk factor.