Oral bioaccessibility of polycyclic aromatic hydrocarbons (PAHs) through fish consumption, based on an in vitro digestion model.

An in vitro gastrointestinal digestion model was used to evaluate bioaccessibility of PAHs in 20 fish species collected from Hong Kong markets. The average bioaccessibilities of PAHs were 24.3 and 31.1%, respectively, in gastric and intestinal conditions. When bioaccessibility was taken into consideration, the values of potency equivalent concentrations (PEC) decreased from 0.53 to 0.18 ng g(-1) for freshwater fish and from 1.43 to 0.35 ng g(-1) for marine fish. This indicated that bioaccessibility should be taken into account for health risk assessment with regard to PAH contamination in fish. The relative accumulation ratios (R(nn)) of PAH congeners were significantly correlated with their physicochemical parameters and their corresponding concentrations reported in subcutaneous fats of Hong Kong residents. The data suggest that R(nn) values calculated in the present study could effectively reflect the accumulations of PAHs in the human body.