Inhalation cancer risk estimation of source-specific personal exposure for particulate matter bound polycyclic aromatic hydrocarbons (PAHs) based on Positive Matrix Factorization (PMF)

摘要

In previous studies, inhalation risk was estimated using conventional risk assessment method, which was normally based on compound specific analysis, and cannot provide substantial data for source-specific particulate matter concentrations and pollution control. In the present study, we applied a new risk analysis method, which was a synthetic combination of source apportionment receptor model and risk assessment method, to estimate cancer risks associated to individual PAHs coming from specific sources. Personal exposure PM samples referring to an elderly panel were collected in a community of Tianjin, Northern China in 2009, and 12 PAH compounds were measured using GC-MS. Positive Matrix Factorization (PMF) was used to extract the potential sources and quantify the source contributions to the PAHs mixture. Then, the cancer risk of each modeled source was estimated by summing up the cancer risks of all measured PAH species according to the extract source profile. We also used the bootstrap simulation inherent in EPA PMF5.0 for the uncertainty analysis. The final results indicated that the overall cancer risk was 2.11×10~(-5), with the largest contribution from gasoline vehicle emission (42.4%). Unlike other risk estimation studies, this study was successful in combining risk analysis and source apportionment approaches, which allow to estimate the potential risk of all source types and provided suitable information to select prior control strategies and mitigate the main air pollution sources that contributing to health risks.