锦州市大气颗粒物中重金属形态分析及生物有效性评价

Speciation analysis and bioaccessibility of heavy metal in atmospheric particulate matters from Jinzhou

研究了锦州市秋冬季大气颗粒物中重金属元素Al、Cd、Cr、Cu、Zn、Pb 的化学形态和生物有效性。结果表明锦州市主要商业街和交通主干道的PM10 和PM2． 5 污染比较严重,冬季取暖期间PM2． 5 平均超标3． 4 倍,最高超标达8． 1 倍。PM10 和PM2． 5 中重金属Zn、Pb 和Cu 的含量较高,在PM10 中最大值分别为0． 903、0． 392、0． 272 μg·m-3 。Cd、Cu、Pb、Zn 在大气颗粒物中主要以酸可提取态(F1 )和氧化物结合态(F2 )存在,这两种形态在环境中易迁移和转化,特别是Cd 的F1 和F2 形态含量之和占总量的95%,其毒性较大。Cd 的含量较低(0． 006 ~0． 018 μg·m-3 ),但富集因子高(1880 ~2819),表明Cd 人为污染严重;Cu、Zn 和Pb 的富集因子较高(>100),表明其受人类活动影响较大。Cd 和Zn 在PM2． 5 中生物有效性系数分别为0． 56 和0． 58,对大气环境和人体健康危害较大。

Chemical speciation and bioaccessibility of heavy metals(Al,Cd,Cr,Cu,Zn,Pb)in atmospheric particulate matters fromJinzhou were studied. The results show that the pollution of PM10 and PM2. 5 in business street and trunk road was relatively serious.The contents of PM2. 5 in winter heating season was 3. 4 times more than the standard,more than 8. 1 times the maximum safe limit.The content of Zn,Pb and Cu in PM10 and PM2. 5 was high,which were 0. 903,0. 392,0. 272 μg·m-3 respectively. The chemical speciationof Cd,Cu,Pb and Zn in atmospheric particulate matters were acid extractable(F1 )and oxides bound(F2 )with a total amountof approximately 95%. The content of Cd was low(0. 006 ~0. 018 μg·m-3 ),but enrichment factor was high(1880 ~2819). The coefficientof biologic effectiveness of Cd and Zn were 0. 56 and 0. 58,which can be a threat to both human health and environment.