Particulate air pollution is widespread, yet we have little understanding of the long-term health implications associated with exposure. We investigated DNA damage, mutation, and methylation in gametes of male mice exposed to particulate air pollution in an industrial/ urban environment. C57BL/CBA mice were exposed in situ to ambient air near two integrated steel mills and a major highway, alongside control mice breathing high-efficiency air particulate (HEPA) filtered ambient air. PCR analysis of an expanded simple tandem repeat (ESTR) locus revealed a 1.6-fold increase in sperm mutation frequency in mice exposed to ambient air for 10 wks, followed by a 6-wk break, compared with HEPA-filtered air, indicating that mutations were induced in spermatogonial stem cells. DNA collected after 3 or 10 wks of exposure did not exhibit increased mutation frequency. Bulky DNA adducts were below the detection threshold in testes samples, suggesting that DNA reactive chemicals do not reach the germ line and cause ESTR mutation. In contrast, DNA strand breaks were elevated at 3 and 10 wks, possibly resulting from oxidative stress arising from exposure to particles and associated airborne pollutants. Sperm DNA was hypermethylated in mice breathing ambient relative to HEPAfiltered air and this change persisted following removal from the environmental exposure. Increased germ-line DNA mutation frequencies may cause population-level changes in genetic composition and disease. Changes in methylation can have widespread repercussions for chromatin structure, gene expression and genome stability. Potential health effects warrant extensive further investigation.DNA adducts ͉ DNA strand breaks ͉ tandem repeat mutation C ombustion of fossil fuels results in the production of complex mixtures of chemicals that are released into the environment and potentially affect millions of people globally. Previous work demonstrated that the offspring of wild birds breeding near integrated steel mills on the North American Great Lakes inherited increased numbers of tandem repeat DNA sequence mutations compared with those from areas without steel mills (1, 2). Subsequent studies investigated expanded simple tandem repeat (ESTR) mutation in outbred laboratory mice caged near two integrated steel mills and a major highway in Hamilton, Ontario, Canada, and at a rural reference site (3, 4). Using a pedigree approach (5), a significant increase in germ-line mutation rate was found in mice housed in the industrial environment compared with the reference site. The majority of mutations were transmitted through the paternal germ line. High-efficiency particulate-air (HEPA) filtration of the ambient air resulted in a significant reduction in mutation frequency, down to levels measured at the reference location (4). Therefore, the particulate fraction of air in this industrial location was largely responsible for the mutagenic hazard.These findings show that chemical pollutants may cause heritable mutation. Further research is required to confirm these results...

The discriminant analyses demonstrated that asthma and healthy groups are distinct from one another. A total of eight components discriminated between asthmatic and healthy children with a 92% correct classification, achieving a sensitivity of 89% and a specificity of 95%. Conclusion The results show that a limited number of VOC in exhaled air can well be used to distinguish children with asthma from healthy children.

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This is the first study distinguishing COPD subjects from controls solely based on the presence of VOCs in breath. Analysis of VOCs might be highly relevant for diagnosis of COPD.

Chronic inflammation has been recognized as a contributing factor in the pathogenesis of lung cancer. In this process, reactive oxygen species released by neutrophils may play an important role. The aim of the present study was to investigate the capacity of the major neutrophilic oxidant hypochlorous acid (HOCl), which is formed by myeloperoxidase (MPO), to induce DNA damage and mutagenicity in lung cells. HOCl was mutagenic in lung epithelial A549 cells in vitro, showing at physiological concentrations a significant induction of mutations in the HPRT gene. We studied three major types of DNA lesions that could be relevant for this HOCl-induced mutagenicity. Single strand DNA breakage and 8-oxo-7,8-dihydro-2'-deoxyguanosine were not found to be increased following HOCl treatment. On the other hand, HOCl caused a significant increase in the formation of 3-(2-deoxy-beta-D-erythro-pentofuranosyl)pyrimido[1,2-alpha]purin-10(3H)-one (M(1)dG), which can be formed by either malondialdehyde (MDA) or base propenals. We observed an increased MDA formation upon exposure of A549 cells to HOCl, but a role of base propenals cannot be excluded. In line with this, we observed 4-fold increased M(1)dG adduct levels in mice that were intratracheally instilled with lipopolysaccharide to induce a pulmonary inflammation with neutrophil influx. Depletion of circulating neutrophils significantly reduced pulmonary MPO activity as well as M(1)dG adducts levels, thereby providing a causal link between neutrophils/HOCl and pulmonary genotoxicity in vivo. Taken together, these data indicate that MPO catalysed formation of HOCl during lung inflammation should be considered as a significant source of neutrophil-induced genotoxicity.