Distribution and risk assessment of trace metals in riverine surface sediments in gold mining area

Abstract

Recognizing the pollution characteristics and potential risks of trace metals in sediments are important to protect water ecosystem safety. In the present study, a systematic investigation was performed to assess the pollution and risk level of trace metals in river sediments located in the greatest gold production base in China. The geo-accumulation index was used to assess the contamination degree. The sediment quality guidelines and potential ecological risk index were employed to complete an ecological risk assessment. A non-carcinogenic health risk assessment was also carried out to evaluate potential adverse health risks. Correlations and principal component analyses were applied to check relationships among trace metals and ascertain potential pollution sources. The results suggested that the sediments in the river were most polluted by As, Cd, and Hg followed by Cu, Pb, and Zn. The assessment of potential human health risk revealed that there was no significant non-carcinogenic risk to the inhabitants. Gold mining and smelting activities and the long-term excessive application of fertilizers and agrochemicals were identified as the main anthropogenic releases. This study contributed an understanding that possible sources, contamination degree, and ecological risk level of trace metals in riverine surface sediments in a gold mining area.