Biomass burning particles in the Brazilian Amazon region: Mutagenic effects of nitro and oxy-PAHs and assessment of health risks

摘要

AbstractEmissions from burning of biomass in the Amazon region have adverse effects on the environment and human health. Herein, particulate matter (PM) emitted from biomass burning in the Amazon region during two different periods, namely intense and moderate, was investigated. This study focused on: i) organic characterization of nitro- and oxy-polycyclic aromatic hydrocarbons (PAHs); ii) assessment of the excess lifetime cancer risk (LCR); and iii) assessment of thein vitromutagenic effects of extractable organic matter (EOM). Further, we compared the sensitivity of two mutagenicity tests:Salmonella/microsome test and cytokinesis-block micronucleus (CBMN) with human lung cells. Among the nitro-PAHs, 2-nitrofluoranthene, 7-nitrobenz[a]anthracene, 1-nitropyrene, and 3-nitrofluoranthene showed the highest concentrations, while among oxy-PAHs, 2-metylanthraquinone, benz[a]anthracene-7,12-dione, and 9,10-anthraquinone were the most abundant. The LCR calculated for nitro-PAH exposure during intense biomass burning period showed a major contribution of 6-nitrochrysene to human carcinogenic risk. The EOM from intense period was more mutagenic than that from moderate period for both TA98 and YG1041Salmonellastrains. The number of revertants for YG1041 was 5–50% higher than that for TA98, and the most intense responses were obtained in the absence of metabolic activation, suggesting that nitroaromatic compounds with direct-acting frameshift mutagenic activity are contributing to the DNA damage. Treatment of cells with non-cytotoxic doses of EOM resulted in an increase in micronuclei frequencies. The minimal effective dose showed thatSalmonella/microsome test was considerably more sensitive in comparison with CBMN mainly for the intense burning period samples. This was the first study to assess the mutagenicity of EOM associated with PM collected in the Amazon region usingSalmonella/microsome test. The presence of compounds with mutagenic effects, particularly nitro- and oxy-PAHs, and LCR values in the range of 10−5indicate that the population is potentially exposed to an increased risk of DNA damage, mutation, and cancer.Graphical abstractDisplay OmittedHighlights•High concentration of nitro- and oxy-PAHs reflected an increased lifetime cancer risk.•Extractable organic matter from moderate and intense burning periods were mutagenic.•The data for YG1041Salmonellastrains were from 5 to 50% higher than TA98.•The EOM was able to increase the micronuclei frequencies in A549 cells.•Salmonella/microsome test was more sensitive than CBMN using human lung cells.High concentration of nitro- and oxy-PAHs reflected an increased lifetime cancer risk. Besides, theSalmonella/microsome test was considerably more sensitive to the organic matter from biomass burning in comparison with CBMN using human lung cells.