长株潭城市群秋季大气颗粒物及其重金属元素污染特征

为研究长株潭城市群大气颗粒物及典型元素污染特征,于2011年11月在长沙、株洲、湘潭三地采集TSP和PM₁₀样品,同期在北京进行采样,以分析颗粒物及其中重金属元素(Cr、Cd、Hg、Pb和As)质量浓度的分布特征. 结果表明:秋季长沙、株洲、湘潭三地的ρ(TSP)均低于北京,背景点(长沙沙坪站)最低,为(110±48)μg/m3. 株洲ρ(PM₁₀)与北京相近,略高于湘潭和长沙,但背景点ρ(PM₁₀)仍为最低. ρ(PM₁₀)/ρ(TSP)在70.26%~95.80%之间,平均值为85.90%. 长株潭城市群的ρ(Cr)、ρ(Hg)、ρ(As)、ρ(Cd)和ρ(Pb)在TSP中分别为37.7~60.7、0.2~1.5、22.7~92.0、4.2~36.8和142.9~508.3ng/m3,在PM₁₀中相应分别为20.4~33.5、0.1~1.0、20.6~74.2、3.8~31.9和126.1~432.4ng/m3. 长株潭城市群各采样点Cd在TSP和PM₁₀中的富集因子均最大,分别为475.8~4690.7和840.5~7489.8；其次为Hg、Pb和As；Cr的富集因子在TSP和PM₁₀中分别为7.8~33.3和9.1~33.6,均为最小. 

Study on the Pollution Characteristics of Atmospheric Particles and Heavy Matals in Autumn in Chang-Zhu-Tan Metropolitan Area

To understand the pollution characteristics of atmospheric particles and heavy metals in Chang-Zhu-Tan metropolitan area, TSP and PM₁₀ samples were collected in Changsha, Zhuzhou and Xiangtan in November 2011. Sampling was also concurrently conducted in Beijing for comparison of the concentrations of TSP and PM₁₀. The concentrations of heavy metals (Cr, Cd, Hg, Pb and As) in both TSP and PM₁₀ samples were measured. Results showed that the average TSP concentrations in Changsha, Zhuzhou and Xiangtan were all less than that in Beijing, with the lowest concentration (110±48) μg/m3] in the background site (Shaping station, Changsha). The average concentration of PM₁₀ in Zhuzhou was similar to that in Beijing, but slightly higher than those in Changsha and Xiangtan. The lowest concentration of PM₁₀ also occurred in the background site, Shaping station of Changsha. The average ratio of ρ(PM₁₀)/ρ(TSP) was 85.90%, ranging from 70.26% to 95.80%. Concerning heavy metals, the ρ(Cr), ρ(Hg), ρ(As), ρ(Cd) and ρ(Pb) were 37.7-60.7,0.2-1.5,2.7-92.0,4.2-36.8and 142.9-508.3ng/m3, respectively, in TSP samples, while they were 20.4-33.5,0.1-1.0,0.6-74.2,3.8-31.9and 126.1-432.4ng/m3, in PM₁₀ samples, in Changsha, Zhuzhou and Xiangtan respectively. The enrichment factor of Cd was the highest (475.8-4690.7,0.5-7489.8in TSP and PM₁₀), followed by Hg, Pb, and As, while that of Cr was the lowest (7.8-33.3,9.1-33.6in TSP and PM₁₀) among heavy metals.