郑州大气PM10的形貌特征及生物活性研究

Morphology and Bioreactivity of PM_(10) in Air of Zhengzhou

采集郑州市区和郊区秋季大气PM10样品，利用场发射扫描电镜（FESEM）和图像分析技术对PM10颗粒进行形貌特征和粒度分布进行分析，同时应用质粒DNA评价法研究了市区和郊区PM10样品的生物活性.结果显示，在市区采集的样品中燃煤飞灰占有相当大的数量，而在郊区采集的样品中矿物质占有较大的数量，粒径分析表明，市区PM10的数量-等效球直径分布较为集中，主要分布在0.1～0.4μm范围内，郊区则相对比较分散;PM10的体积-等效球直径主要分布在〉1μm范围内。结果表明，在郑州市秋季大气PM10中，数量上细粒子占优势，而在体积上（质量上）较粗颗粒占优势，质粒DNA评价结果表明，郑州市区和郊区PM10颗粒对DNA的损伤程度不同，市区样品的生物活性大于郊区样品。

PM10 was collected at the urban and suburban sites of Zhengzhou city during autumn. High solution field emission scanning electron microscopy （FESEM） and image analysis （IA） were used to analyse the morphology and size distribution of individual particles in PMjo. Plasmid DNA assay was employed to investigate the bioreactivity of PM10. The results showed that the coal fly ash particles were dominated in the PM10 at the urban site while mineral particles were dominated at the suburban site. The number-size distribution showed that the PM10 at the urban site was mainly concentrated in the range of 0.1 μm to 0.4 μm, but the PM10 at the suburban site was scattered in a relatively wider size range. The volume-size distribution demonstrated that the PMio from both urban and suburban sites occurred mainly in the size range 〉 1 μm. These facts showed that by number the fine particles were prevailing in the PM10, while by volume （mass） the coarse particles had a major contribution to the total PM10. The results from plasmid assay showed that the bioreactivity of the urban PM10 was obviously higher than that of the suburban PM10.