Size Distributions and Health Risks of Particulate Polycyclic Aromatic Hydrocarbons in the Atmosphere at Coastal Areas in Ningbo, China.

This article focuses on the size distributions, respiratory deposition, and health risk assessment of particulate polycyclic aromatic hydrocarbons (PAHs) in a coastal area of Ningbo, China. Using an Anderson eight-stage air sampler over one year, the study analyzed 16 US Environmental Protection Agency (USEPA) priority PAHs associated with size-segregated particulate matter (PM) and applied the multiple-path particle dosimetry (MPPD) model to estimate respiratory deposition in children, adult males, and females. Results showed a bimodal PAH distribution with peaks in accumulation mode (0.43–0.65 µm) and coarse mode (4.7–5.8 µm), with coarse PM depositions significantly higher in children, indicating greater health risks for this group. The incremental lifetime cancer risks (ILCR) for all groups were below the USEPA guideline value, and the study highlighted that incorporating particle size and deposition rates avoids overestimation of respiratory exposure and associated health risks.