北京大气环境中的重金属元素

重金属进入环境后会广泛分布于大气、水体、土壤和生物体中。它会长期积累、长程迁移或与其它物质发生化学反应生成有害物质。大气环境中的重金属元素有来自工业生产中的排放物,机动车的排气,燃煤燃油的产物;也有来自天然来源,如风砂、土壤或扬尘。这些重金属一般以颗粒状态分散于大气中,会进入人体呼吸系统,被血液吸收而危害健

Heavy Metals in the Beijing Atmosphere

Variations in concentrations of some heavy metals have been observed in different seasons for four years in Beijing area. The results showed that in general the concetra-tions of heavy metals in particulates were higher in winter than in summer and autumn. The heavy metals Pb,Zn and Cr in fine particles (<2.3μm) were found to be high at all sampling sites. The enrichment factor (EF) of some heavy metals were calculated. The EF values of metal Fe and Mn at the district of steel industry were higher than those of other sites,but metals Cu,Pb,Zn,Cd,Cr,Co and Mo had high EF values in all sites. This might be due to pollution of anthropogenic sources.The increasing coal combustion in winter and automobile exhaust would be one of important anthropogenic sources of air pollution in Beijing.