Distribution, Sources, and Risk of Polycyclic Aromatic Hydrocarbons in the Core Sediments from Baiyangdian Lake, China

摘要

The burial characteristics and risks of 16 polycyclic aromatic hydrocarbons (PAHs) in core sediments from Baiyangdian Lake were investigated through gas-chromato graphy/mass spectrometry. The total concentrations of the 16 PAHs ranged from 39.48-1877.75 ng g~(-1). The low-molecular-weight PAHs (two- to three-ring PAHs) were the dominant species, contributing 40.10-92.18% to the total PAHs, with a mean of 71.01%. Based on the observed molecular indices and on principal component analysis, the PAHs inputs were initially dominated by biomass and coal combustion, and atmospheric deposition and surface runoff could be the major transport pathways. The contaminated source characteristics, hydrodynamic condition, and sediment textural composition are the key factors affecting the distribution and source of PAHs. By conducting a risk quotient analysis between specific PAH concentrations and their corresponding sediment quality values, the top layer sediments were found to have a potential biological impact and relatively high toxicity. However, such impact should have no impairment. The toxic potency of PAHs in Baiyangdian Lake could be described by using the toxic equivalent of benzo[a]pyrene.