The distribution, accumulation and potential source of seldom monitored trace elements in sediments of Beijiang River, South China

A geochemical study of Beijiang River sediments was carried out to analyze the concentrations, distribution, accumulation and potential sources of the seldom monitored trace elements (SMTEs: Sc, V, Co, Ga, Y, Sn and Sb). The mean concentrations of Sc, V, Co, Ga, Y, Sn and Sb were 8.2, 60.3, 9.6, 17.2, 28.6, 85.6 and 39.0 mg/kg, respectively. The concentrations of the SMTEs, together with their spatial distribution showed that the SMTEs were mainly due to anthropogenic inputs from the metal smelting industries and local mining activities in the upper region of the river. The assessment by geoaccumulation index indicates that Sc, V, Co, Ga and Y are at the unpolluted level, Sn is at the ‘strongly contaminated’ level, and Sb is at the ‘extremely contaminated’ level. The pollution level of the SMTEs is: Sb > Sn > Y > Ga > Co > V > Sc. The results of correlation analysis and principal component analysis indicated the Sn and Sb were positively correlated with each other, indicating a common source in sediments. In conclusion, our results indicate that the sediments in Beijiang River have been severely contaminated by Sn and Sb.