Ingestion bioaccessibility of indoor dust-bound PAHs: Inclusion of a sorption sink to simulate passive transfer across the small intestine

Abstract In this study, we investigated the levels of 12 priority polycyclic aromatic hydrocarbons (PAH 12 ) pollutants, bioaccessible PAH 12 , and sorption sink for PAH 12 by a silicone sheet of indoor dust samples, which were collected from teachers' offices (n = 17), students' offices (n = 17), laboratory (n = 11), and experimental center (n = 9), using an in vitro digestive model. In PAH 12 , bioaccessible PAH 12 , and sorption sink PAH 12 , benzo[ b ]fluoranthene (BbF), phenanthrenes (Phe), and fluoranthene (FLA) were labeled respectively the most significant PAHs (6.61 ± 4.42 μg/g, 0.16 ± 0.11 μg/g, and 0.08 ± 0.06 μg/g) after indoor dust ingestion, whereas the proportions of anthracene (Ant), benzo(g,h,i)perylene (BghiP), and BghiP (0.34 ± 0.17, 0.03 ± 0.03 and 0.01 ± 0.01 μg/g) were low. Based on benzo[ a ]pyrene- equivalent carcinogenic concentrations, the mean daily exposure of bioaccessible PAH 12 and sorption sink for PAH 12 by indoor dust ingestion was 4.07 × 10 −3  ± 1.73 × 10 −3 and 3.23 × 10 −3  ± 1.36 × 10 −3  μg/day in the experimental center; 4.01 × 10 −3  ± 2.05 × 10 −3 and 1.46 × 10 −3  ± 6.72 × 10 −4  μg/day in students' offices; 8.25 × 10 −4  ± 2.33 × 10 −4 and 5.15 × 10 −4  ± 1.37 × 10 −4  μg/day in laboratory; and 7.05 × 10 −4  ± 4.12 × 10 −5 and 2.82 × 10 −4  ± 4.36 × 10 −5  μg/day in teachers' offices, respectively. Our results indicated that the passive transfer fraction of PAH 12 (44.07%–67.36% in this case) is therefore large and needs to be considered in exposure and risk assessments.