Polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the largest deep plateau lake in China: Occurrence, sources and biological risk

The unprecedented rate at which economy, urbanization and industrialization have occurred in China in the last few decades has resulted in environmental pollution in China. Polycyclic aromatic hydrocarbons (PAHs) are of great concern because of their persistence, long-range transport properties, and health risk as potential carcinogens and mutagens. Plateau lakes are special ecosystem and located in remote western China. To our knowledge, studies on PAHs in sediments of plateau deep lakes in China are scarce. Therefore, PAHs in surface sediments from Fuxian Lake, the largest deep plateau lake in China, were investigated. The total PAH concentrations ranged from 83.2 to 261.7, with a mean concentration of 143.3 ng/g. Four-ring PAHs (39.173.9%) were most abundant in all samples. The composition of PAHs was characterized by high molecular weight PAHs, and FA and PHE were the dominant constituents. A correlation analysis revealed that TOC was positively significantly correlated with total PAHs, while percentages of grain size fraction were poorly correlated with total PAHs. PAH diagnostic ratios demonstrated that PAHs mainly originated from biomass, coal, and petroleum combustion. Taking as a whole, surface sediments of Fuxian Lake had a 9% incidence of adverse biological effects based on the mean effects range-median quotient. (C) 2017 Elsevier B.V. All rights reserved.