Characterization of PAHs in surface sediments of aquaculture farms around the Pearl River Delta

The distribution and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of freshwater fishponds and mariculture rafts around the Pearl River Delta (PRD) were investigated. Twenty-one sample sites were chosen, consisting of fifteen freshwater fishponds and six mariculture rafts. The total PAH ( summation SigmaPAH) concentrations measured in all the sediment samples ranged from 52.7 to 717 ng g(-1), with mean of 184 ng g(-1). The marine sediment samples contained higher levels of summation SigmaPAH, high molecular weight (HMW) PAHs and carcinogenic PAHs than freshwater sediments (p