A method for assessing carcinogenic risk of air fine particle-associated polycyclic aromatic hydrocarbons by considering bioaccessibility in lung fluids.

This study was conducted to evaluate the inhalation carcinogenic risk of PAHs in biochar fine particles using total concentration-based assessment approach and bioaccessibility-based assessment approach. Only limit PAHs in particles can be released in simulated lung fluids, leading to a low bioaccessibility (only ranging from 0.34% to 1.48% for biochar fine particles and from 3.21% to 44.2% for PM2.5), which would significantly affect health risk assessment. Therefore, bioaccessibility should always be favored over more traditional evaluations based on total concentration, while evaluating inhalation health risks of biochar-bound PAHs. To prove the broad applicability of bioaccessibility-based assessment approaches, we also compared health risk of actual atmospheric particles (PM2.5 collected from Nanjing, China) using total concentration-based approaches and bioaccessibility-based approaches.