Prediction of the bioaccumulation of PAHs in surface sediments of Bohai Sea, China and quantitative assessment of the related toxicity and health risk to humans.

Assessing the health risk of PAHs in sediments was quite difficult because sediment occurred in sea floor, and it was very hard to contact with them directly for humans. This study was attempted to reveal the relationship between concentrations of PAHs in surface sediments and health risk of seafood consumers. The transfer (bioaccumulation) of PAHs from surface sediment into benthic organisms was predicted. Source contributions to PAHs and related toxicity and health risks (from intake of PAHs-contaminated benthic organisms) were studied based on PMF model and Monte Carlo simulation, respectively. Total concentrations of PAHs (TPAHs) ranged from 149.40 to 1211.97 ng g(-1) in sediments of Bohai Sea (BS), China. Petroleum and vehicular emission, coal combustion and coke oven constituted 40.0%, 32.2% and 27.8% of PAHs, respectively, but contributed 53.0%, 22.8% and 24.2% of toxicity posed by PAHs in sediment. For children, teens and adults, the 95th percentile carcinogenic and non-carcinogenic risks were below the threshold values of 10(-6) and 1.0, respectively, suggesting no potential health risk. Sensitivity analysis suggested that exposure duration (ED) and PAH concentrations (CS) were the two most sensitive parameters in risk assessment. The results provided a method to evaluate the quality of sediments and the potential health risk related to PAHs in marine sediments.