Ecological risk analysis of polycyclic aromatic hydrocarbons (PAHs) in surface sediments from Laizhou Bay.

Concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in surface sediments collected from 17 stations in Laizhou Bay were measured by gas chromatography-mass spectrometry. The results showed that the total concentrations of PAHs varied from 23.3 to 292.65 ng/g with a mean value of 134.27 ng/g. The total PAHs concentrations were at lower level compared to other marine coastal areas. The proportion of two to four ring PAHs was quite high. Sediment quality guidelines (SQGs) were conducted to assess the toxicity posed to the benthic community by PAHs. It was showed that concentrations of PAHs were below their respective effects range-median (ERM) and probable effects level (PEL) values in 17 stations using effects range-low (ERL)/ERM values and threshold effects level (TEL)/PEL values. Acenaphthene concentrations in surface sediment exceed TEL only in station L14, the concentrations were at levels where adverse biological effects may occasionally occur (> or =TEL and or =ERL/TEL and or =TEL and