One-Hundred-Year Sedimentary Record of Polycyclic Aromatic Hydrocarbons in Urban Lake Sediments from Wuhan, Central China

Abstract

The concentrations and depositional fluxes of polycyclic aromatic hydrocarbons (PAHs) were investigated in a dated sediment core collected from Donghu Lake, central China. Total concentrations of 16 PAHs ranged from 33.32 to 937.24 ng g−1 based on dry weight. Depositional fluxes of total PAHs, ranging 15.84–387.37 ng cm−2 year−1, were in relatively higher levels compared with those in the cores collected from other areas of China. The concentrations and fluxes of total and individual PAHs changed dramatically with depth, reflecting energy usage changes and closely following the historical economic development in central China. Since the initiation of the “Reform and Opening-Up policy” in the late 1970s, the levels of PAHs, especially the high-molecular-weight carcinogenic PAHs, increased rapidly and reached the highest value in recent years, indicating the growth of incomplete combustion of coal and petroleum with the development of economy in this area. Furthermore, analysis of isomer ratios and principle component analysis commonly revealed the main contribution of anthropogenic pyrolytic source to PAH contamination in the largest urban lake of China.