Gutiérrez-Castillo Maria E, Roubicek Deborah A, Cebrián-García Mariano E, De Vizcaya-Ruíz Andrea, Sordo-Cedeño Monserrat, Ostrosky-Wegman Patricia
Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados IPN, Mexico D.F., Mexico.
Environ Mol Mutagen. 2006 Apr;47(3):199-211. doi: 10.1002/em.20186.
Airborne particulate matter (PM) contains a large number of genotoxic substances capable of endangering human health. In the present study, we have investigated the ability of chemically characterized water-soluble and organic-soluble fractions of two particle sizes (PM2.5 and PM10) from different regions of Mexico City to induce DNA damage in a human lung epithelial cell line. We also evaluated associations between the physicochemical parameters of the PM and its genotoxicity. The airborne particulate samples were collected from four regions of the city; a HiVol air sampler was used to collect PM10 on glass fiber filters and a tapered element oscillating system coupled to an automatic cartridge collection unit was used to collect PM2.5 on teflon filters. PM mass was determined by gravimetric analysis of the filters. Filters containing PM2.5 and one section of each PM10 filter were agitated either with deionized water to extract water-soluble compound, or with dichloromethane to prepare organic-soluble compounds. The chemical composition of the extracts was determined by ion and gas chromatography and atomic adsorption spectroscopy. A549 human type II alveolar epithelial cells were exposed to different concentrations of the PM2.5 and PM10 extracts, and alkaline single cell gel electrophoresis or the Comet assay was performed to measure DNA damage and repair. These analyses indicated that soluble transition metals and the organic-soluble PM fractions are crucial factors in the DNA damage induced by PM. PM composition was more important than PM mass for producing genotoxicity. The results of this study showed that the constituents of the water-soluble PM extract are more likely to induce DNA damage than the organic compounds.
空气中的颗粒物（PM）含有大量能够危害人类健康的基因毒性物质。在本研究中，我们调查了来自墨西哥城不同区域的两种粒径（PM2.5和PM10）的化学特征水溶性和有机溶性组分在人肺上皮细胞系中诱导DNA损伤的能力。我们还评估了PM的物理化学参数与其基因毒性之间的关联。空气颗粒物样本从城市的四个区域采集；使用高容量空气采样器在玻璃纤维滤纸上采集PM10，使用与自动滤芯收集装置相连的锥形元件振荡系统在聚四氟乙烯滤纸上采集PM2.5。通过对滤纸的重量分析确定PM质量。含有PM2.5的滤纸和每个PM10滤纸的一部分，要么用去离子水搅拌以提取水溶性化合物，要么用二氯甲烷搅拌以制备有机溶性化合物。通过离子色谱、气相色谱和原子吸收光谱法测定提取物的化学成分。将A549人II型肺泡上皮细胞暴露于不同浓度的PM2.5和PM10提取物中，并进行碱性单细胞凝胶电泳或彗星试验以测量DNA损伤和修复。这些分析表明，可溶性过渡金属和有机溶性PM组分是PM诱导DNA损伤的关键因素。对于产生基因毒性而言，PM的组成比PM质量更重要。本研究结果表明，水溶性PM提取物的成分比有机化合物更有可能诱导DNA损伤。
