不同通勤模式暴露于VOCs的健康风险评价

Health Risk Assessment of Volatile Organic Compounds for Different Commuting Modes

针对国内外交通微环境VOCs健康风险研究中通勤模式和有害挥发物较为单一的不足,选取广州市家庭轿车、空调公共汽车、非空调公共汽车、地铁和自行车这5种通勤模式中的苯、甲苯、二甲苯、乙苯、苯乙烯、甲醛、乙醛和丙烯醛等8种VOCs,运用Monte-Carlo模拟方法,进行健康风险评价并对各吸入暴露参数做出敏感性分析.结果表明,空调公交车和家庭轿车的致癌风险较大,分别服从t分布和对数正态分布,为1.65×10^(-5)±5.74×10^(-9)和5.01×10^(-6)±3.56×10^(-11),超过10^(-6)的概率分别为97%和74.85%,自行车和非空调公交车次之,地铁的致癌风险最小,但平均值皆超过10^(-6);家庭轿车和空调公共汽车的非致癌风险较大,服从对数正态分布,分别为2.51±2.74和1.20±1.36,其中丙烯醛的贡献皆在80%以上,骑自行车的非致癌风险较小,预期将不会对人体健康产生威胁;各暴露参数中,对健康风险敏感度较大的依次为:每天的暴露时间(ET)、有害挥发物的浓度(CA)、终生暴露年限(ED)、呼吸速率(IR)和每年的暴露天数(EF),而体重(BW)具有负敏感性.

In order to overcome the shortcomings of a single commuting mode,eight VOCs including benzene,toluene,xylene,ethylbenzene,styrene,formaldehyde,acetaldehyde,and acrolein were studied in five commuting modes in Guangzhou. Applying the Monte Carlo simulation method,we assessed the health risk of these VOCs in five commuting modes,cars,air-conditioned buses,nonair-conditioned buses,subways,and bicycles,and analyzed the sensitivity of each exposure parameter. We used Crystal Ball 11. 1 with10 000 iterations of independent runs and 95% confidence interval. The results show that the commuters of air-conditioned buses and cars are subjected to a higher cancer risk,following the t-distribution and lognormal distribution with 1. 65 × 10-5± 5. 74 × 10-9 and5. 01 × 10^（-6）± 3. 56 × 10-11,with the probability of exceeding 10^（-6） of 97% and 74. 85%,respectively. The cancer risks of bicycles,non-air-conditioned buses,and subways are smaller,but their averages are higher than 10^（-6）. The commuters of cars and airconditioned buses were subjected to a larger non-cancer risk,following the lognormal distribution of 2. 51 ± 2. 74 and 1. 20 ± 1. 36; the contributions of acrolein are above 80%. The non-cancer risk of bicycles is the smallest and will not be a threat to human health.Sensitivity analysis shows that the sensitivities of ET,CA,ED,IR,and EF are larger,with the values of 55. 5%,32%,10. 5%,1. 1%,0. 2%,respectively,and BW has negative sensitivity.