Distribution, source and pollution level of heavy metals in river sediments from South China

The sediment pollution caused by heavy metals has attracted a great deal of attention due to its persistence, bioaccumulation and toxicity. This research was the first to consider the whole of South China to obtain an overall profile of heavy metal spatial distribution, possible sources and pollution levels in river systems. For these data, 14 selected heavy metals were analysed in river sediments collected from sampling sites in Guangdong, Fujian, Guangxi and Hainan Provinces. The geoaccumulation index and enrichment factor revealed that river systems in South China were universally contaminated by Cd, As and Sn, which might be distributed by anthropogenic activities. Moreover, Guangdong Province, a relatively developed area in South China, was relatively polluted by certain heavy metals such as Ni, Cu, Zn and Mn. Multivariate statistical analyses such as Pearson's correlation matrix and a principal component analysis determined that several of the heavy metals might be derived from similar anthropogenic activities such as industrial effluents and domestic sewage discharge. In terms of heavy metal contamination in South China, necessary measures should be undertaken to protect rivers in South China.