Global lung cancer risk from PAH exposure highly depends on emission sources and individual susceptibility

The health impacts of polycyclic aromatic hydrocarbons (PAHs), the most concerning organic pollutants, depend not only on the locations and strengths of emission sources, but also on individual susceptibility. Moreover, trans-boundary transport makes them a global concern. In this study, a comprehensive analysis of the global health impacts of polycyclic aromatic hydrocarbons (PAHs) in ambient air is presented. Model resolution is critical in exposure modelling. Globally, incremental lifetime lung cancer risk (ILCR) induced by ambient PAH exposure is 3.1 × 10^-5. If the individual susceptibility was not taken into consideration, the overall risk would be underestimated by 55% and the proportion of highly vulnerable population would be underestimated by more than 90%. Emphasizing on individual susceptibility, our study provides an instrumental revision of current risk assessment methodology. In terms of lung cancer risk, the most important sources are combustion of biomass fuels (40%) and fossil fuels (14%) in the residential/commercial sector, coke (13%) and aluminium (12%) production, and motor vehicles (9%). PAHs can travel long distance globally especially within the Eurasian continent. Still, the risk is dominantly contributed by local.