An apportionment method for the oxidative potential of atmospheric particulate matter sources: application to a one-year study in Chamonix, France

摘要

Inhaled aerosolized particulate matter (PM) induces cellular oxidative stress invivo, leading to adverse health outcomes. The oxidative potential (OP) of PMappears to be a more relevant proxy of the health impact of the aerosol ratherthan the total mass concentration. However, the relative contributions of theaerosol sources to the OP are still poorly known. In order to better quantifythe impact of different PM sources, we sampled aerosols in a French city for oneyear (2014, 115 samples). A coupled analysis with detailed chemicalspeciation (more than 100 species, including organic and carbonaceous compounds,ions, metals and aethalometer measurements) and two OP assays (ascorbic acid, AA, and dithiothreitiol, DTT) in a simulated lung fluid (SLF) were performedin these samples. We present in this study a statistical framework using acoupled approach with positive matrix factorization (PMF) and multiple linearregression to attribute a redox-activity to PM sources. Our results highlightthe importance of the biomass burning and vehicular sources to explain theobserved OP for both assays. In general, we see a different contribution of thesources when considering the OP AA, OP DTT or the mass of thePM10. Moreover, significant differences are observed betweenthe DTT and AA tests which emphasized chemical specificities of the two testsand the need of a standardized approach for the future studies onepidemiology or toxicology of the PM.