天津市某社区老年人PM2.5暴露痕量元素健康风险评估

为研究PM_2.5暴露特征,对天津市某社区101名老年人(平均年龄67岁)夏季(2011年6月13日—7月2日)和冬季(2011年11月30日—12月12日)的PM_2.5暴露水平进行了监测,并分析了PM_2.5载带痕量元素的含量及其健康风险. 结果表明,研究对象夏、冬两季PM_2.5个体暴露浓度分别为(124.2±75.2)、(170.8±126.6)μg/m3,室内暴露浓度分别为(120.0±48.9)、(164.9±125.7)μg/m3,环境暴露浓度分别为(98.6±33.3)、(140.0±87.7)μg/m3. 10种痕量元素中,ρ(Zn)最高,夏季为324.18~345.65ng/m3,占痕量元素总质量浓度的37%以上；冬季为148.36~362.00ng/m3,占痕量元素总质量浓度的35%以上. V、Cr、Mn、Cu、Zn和Pb的非致癌风险值均小于1,理论风险较小；但其中Cr和Mn风险值均超过0.1〔HQ(风险系数)分别为0.882和0.306〕,对于属于易感人群的老年人群体,仍有可能对其身体健康产生危害,需引起重视；As、Cd和总体致癌风险均超过10-6,对人体健康的危害不容忽视. 

Health Risk Assessment of Trace Elements of PM2.5 Exposure for the Elderly Subpopulation in Tianjin, China

To investigate exposure characteristics of PM_2.5, a panel study was conducted for elderly subpopulation in Tianjin. Totally 101elderly participants with mean age 67were selected and their exposure to PM_2.5 were monitored longitudinally in summer (13th June-2nd July) and winter (30th November-12th December) of 2011. Personal and indoor PM_2.5 samples were collected by a personal environmental sampler. Ambient PM_2.5 samples were obtained by a median-volume PM_2.5 sampler. All samples were analyzed using inductively coupled plasma-mass spectroscopy (ICP-MS) for trace elements (V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd and Pb). The results showed that the personal, indoor and ambient PM_2.5concentrations were (124.2±75.2) μg/m3, (120.0±48.9) μg/m3, (98.6±33.3) μg/m3for summer, and (170.8±126.6) μg/m3, (164.9±125.7) μg/m3, (140.0±87.7) μg/m3for winter, respectively. The result of the concentration analysis for trace elements showed that Zn was the most abundant element, accounting for over 37% of the total trace element concentration in summer (324.18-345.65ng/m3) and over 35% in winter (148.36-362.00ng/m3). The hazards quotients (HQ) of 6non-cancer-risk elements (V, Cr, Mn, Cu, Zn and Pb) were below 1. The HQ of Cr and Mn were higher than 0.1, which might have non-cancer-risk for the elderly subpopulation. The median value of Incremental Lifetime Cancer Risk (ILCR) of As was 1.12×10-5. The total ILCR and ILCRs of As and Cd were all higher than the acceptable risk level of 10-6, indicating an unacceptable potential cancer risk.