北京大学生个体臭氧暴露直接测量及潜在健康风险评估

Measurement of Individual Ozone Exposure and Assessment of Potential Health Risks Among College Students in Beijing

为探究个体臭氧暴露量与臭氧环境监测值之间的关系,准确评估北京市臭氧污染的健康风险,本工作利用小型臭氧测量仪,直接测量在校大学生的个体臭氧暴露浓度,获取了北京地区特定群体个体平均臭氧暴露浓度与环境中臭氧监测值之间的定量关系。根据臭氧暴露浓度与人体健康效应关系模型,对北京地区2018-2020年大学生群体的臭氧污染健康风险进行了评估。结果表明,大学生群体日间个体暴露率为39±1%。取《环境空气质量标准》(GB3095—2012)中规定的臭氧浓度一级标准限值(100μg/m^(3))作为健康风险评估的参考浓度,则大学生群体归因臭氧污染过早死亡人数在2018、2019和2020年分别为14人、20人和23人。暴露率增加20%,臭氧健康风险约增加2~3倍;暴露率增加50%,臭氧健康风险约增加6~8倍。参考浓度取较低阈值26.7ppb时,评估得到的健康风险约升高了两倍。在一天24h内,下午13时到17时臭氧造成的健康危害最大,在一年四季中,夏季臭氧造成的健康危害最大,这与大气臭氧浓度变化规律相一致。在臭氧污染严重的天气,应尽量减少室外活动或者采取防护措施,以降低臭氧暴露带来的健康风险。

To investigate the relationship between individual ozone exposure and environmental ozone monitoring values, and to accurately assess the health risk of ozone pollution in Beijing, this work directly measured individual ozone exposure of university students in university using a personal ozone monitor, and obtained the quantitative relationship between individual ozone exposure and environmental ozone monitoring values for a specific group in Beijing. Based on the relationship model between ozone exposure and human health effects, the ozone health risk on student population of the universities in Beijing from 2018 to 2020 was assessed. The result showed that the daytime individual exposure rate of the university student population was 39±1%. Taking the primary standard limit of ozone concentration(100 g/m^(3)) specified in the Ambient Air Quality Standard(GB3095-2012) as the reference concentration for health risk assessment, the numbers of premature deaths attributed to ozone pollution in the university student population were 14, 20 and 23 in 2018, 2019 and 2020, respectively. A 20% increase in exposure increased the ozone health risk by approximately 2-3 times;a 50% increase in exposure increased the ozone health risk by approximately 6-8 times. At the lower threshold of 26.7 ppb for the reference concentration, the assessed health risk was approximately twofold higher. The health risk from ozone was much greater from 13:00 to 17:00 p.m. during the day and in the summer months of the year than in other times, which was consistent with the pattern of variations in ambient air ozone concentrations. During days of high ozone levels, outdoor activities should be minimized or protective measures should be taken to reduce the health risks associated with ozone exposure.