Distribution and potential ecological risk of polycyclic aromatic hydrocarbons in the sediments from typical electronics industrial zone

In order to investigate the polycyclic aromatic hydrocarbons (PAHs) contamination status in a river of a typical electrical equipment industrial area, Ronggui, Foshan, 8 sediments simples were collected. The results showed that 12 components of PAHs were detected in all sediment samples, and the other 4 components were also detected in different degree. The total 16 EPA priority PAHs contents in surface sediments varied from 343.5 μg·kg^-1 to 2099 μg·kg^-1(dry wt), with an average of 1215.9 μg·kg^-1, and no significant variation was found in vertical distribution. The 2 to 3 aromatic rings were the dominant PAHs, and they accounted for 50.6% to 82.5% of the total PAHs. Diagnostic ratios were used to identify the possible sources of PAHs, and the results indicated that PAHs were mainly pyrogenic origin. Sediments were polluted by PAHs heavily according to Maliszewska-Kordybach's standard, the very high risk level was also confirmed by the contamination factors assessment which was investigated by comparison with the background area (S0). The assessment by the method of sediment quality guidelines (SQGs) and relative contamination factor (RCF) demonstrated that adverse biological toxicity effect might occasionally happen in a few sampling sites, and the ecological risk components included acenaphthene (Ace), fluorine (Flu), and phenanthrene (Phe).