Institute for Environment and Resources (IER), 142 To Hien Thanh St., Dist. 10, HCMC, Ho Chi Minh City 700000, Vietnam.
Department of Academic Affairs, Vietnam National University, Ho Chi Minh City 700000, Vietnam.
Int J Environ Res Public Health. 2022 Dec 2;19(23):16156. doi: 10.3390/ijerph192316156.
Benzene, toluene, ethylbenzene, and xylenes (BTEX) are carcinogenic pollutants. However, the average concentration in 1 h of some pollutants belonging to BTEX, such as benzene, in Ho Chi Minh City (HCMC) is higher than the national standard QCVN 06:2009/BTNMT by about ten times. This research is the first to calculate the emission of BTEX for developing countries on a city scale. This paper developed a method to calculate cold emission factors based on hot emission factors for BTEX. Five spreadsheets developed and calculated these cold emission factors for five vehicle categories. A comprehensive emission inventory (EI) for BTEX was conducted in HCMC to determine the cause of BTEX pollution. An innovative methodology with bottom-up and top-down combination was applied to conduct BTEX EI, in which the EMISENS model was utilized to generate the EI for road traffic sources, and the emission factors method was utilized for other emission sources. Among emission reasons, motorcycles contribute the highest to HCMC air pollution, responsible for 93%, 90%, 98.9%, and 91.5% of benzene, toluene, ethylbenzene, and xylene, respectively. Cars contributed 5%, 6%, 0.8%, and 6.5% of benzene, toluene, ethylbenzene, and xylene, respectively. For LDVs, the emission from benzene, toluene, ethylbenzene, and xylene accounted for 1%, 2%, 0.2%, and 1.9%. The major reasons for point sources were metal production, which had 1%, 2%, and 0.1% for benzene, toluene, ethylbenzene, and xylenes emissions. The area source had a minority emission of total BTEX in Ho Chi Minh City. Our findings can be used to invest in the most significant sources to reduce BTEX in HCMC. Our approach can be applied in similar urban areas in BTEX EI. This research also developed nine measures to reduce BTEX in HCMC for human health protection.
苯、甲苯、乙苯和二甲苯（BTEX）是致癌污染物。然而，胡志明市（HCMC）某些 BTEX 污染物，如苯，1 小时内的平均浓度比国家排放标准 QCVN 06:2009/BTNMT 高出约 10 倍。这项研究是首次在城市范围内计算发展中国家的 BTEX 排放量。本文开发了一种基于热排放因子计算 BTEX 冷排放因子的方法。开发了五个电子表格，用于计算五类车辆的冷排放因子。在胡志明市进行了 BTEX 综合排放清单（EI），以确定 BTEX 污染的原因。应用了一种自下而上和自上而下相结合的创新方法来进行 BTEX EI，其中利用 EMISENS 模型生成道路交通源的 EI，利用排放因子法进行其他排放源的 EI。在排放原因中，摩托车对胡志明市空气污染的贡献最大，分别占苯、甲苯、乙苯和二甲苯的 93%、90%、98.9%和 91.5%。汽车分别贡献了 5%、6%、0.8%和 6.5%的苯、甲苯、乙苯和二甲苯。对于 LDVs，苯、甲苯、乙苯和二甲苯的排放量分别占 1%、2%、0.2%和 1.9%。点源的主要原因是金属生产，苯、甲苯、乙苯和二甲苯的排放量分别占 1%、2%和 0.1%。区域源对胡志明市总 BTEX 的排放量较小。我们的研究结果可用于投资于最重要的来源，以减少胡志明市的 BTEX。我们的方法可应用于 BTEX EI 中类似的城市地区。本研究还为保护人类健康制定了九项减少胡志明市 BTEX 的措施。
