Winter air pollution by and inhalation exposure to nitrated and oxygenated PAHs in rural Shanxi, north China

Polar polycyclic aromatic hydrocarbons (PAHs) derivatives like nitrated and oxygenated PAHs have higher toxic potentials than the parent one, and are receiving growing interests. In this study, we investigated household air pollution and personal exposure to nitro- and oxy-PAHs during a winter period in rural Shanxi, northern China. The overall arithmetic means of 24-h average indoor nitro-PAHs and oxy-PAHs were 10.2 ± 3.6 and 76.8 ± 51.8 ng/m³, respectively, that were much higher than the 7.98 ± 4.30 and 54.7 ± 45.4 ng/m³ in the outdoor air. Nearly 90% of particulate PAHs derivatives were enriched in fine PM_2.5 and even finer PM_1.0 fraction. Daily inhalation exposure to nitro- and oxy-PAHs for the rural population were 8.41 ± 3.08 and 68.5 ± 79.7 ng/m³, respectively. Residents burning briquette for cooking were found to have lower household air pollution and exposure levels compared with those burning wood. The calculated time-weighted average concentration overestimated, though correlated positively, the daily inhalation exposure compared to the that from personal carried samplers.