Lung cancer risk by polycyclic aromatic hydrocarbons in a Mediterranean industrialized area

This study focuses on characterizing the chronic risk assessment from inhalation of polycyclic aromatic hydrocarbons (PAHs) for people living near the largest chemical complex in the Mediterranean area. Eighteen PAHs were determined in the atmospheric gas and particle phases, counting PM₁₀ and total suspended particles. The lifetime lung cancer risk from PAH exposure was estimated, and the contribution was assessed by phases. The results obtained with the continuous lifetime scenario were compared with those obtained with different chronic scenarios. The estimated chronic risk was also compared with those reported in previous studies. PAHs were present at higher concentration in the gas phase (>84 %) with a major contribution of the most volatile PAHs, and an equitable distribution of heavy PAHs between gas and particle phases was observed. Petroleum combustion and traffic emissions were suggested as the main sources, but the influence of petrogenic sources cannot be ruled out. The estimated average lifetime lung cancer risk in this study ranged between 3.2 × 10^-5 and 4.3 × 10^-5. The gas phase accounted for the most significant contribution to the total risk (>60 %). Fluoranthene (FluT), dibenzo(a,h)anthracene (DahA) and benzo(a)pyrene (BaP), as a whole, made the greatest contribution to the total risk (>80 %). BaP-bound PM₁₀ accounted for a small contribution of the total risk (10 %). Chronic exposures lower than total lifetime hours could even pose a risk >10^-5. The results also showed that BaP-bound PM₁₀, according to current legislation, may not be a good indicator of the real risk by PAH exposure. Concerning previous studies, the economic situation may have an impact on reducing the cancer risk by PAH inhalation.