城市居民CO_(2)实时暴露特征与家庭个体差异

Real-time Evaluation of Domestic Exposure to CO_(2) in Sichuan,China:Space Function-associated Characteristics and Variations among Family Members

CO_(2)是室内空气质量的重要指标,然而有关居民个体CO_(2)实时暴露研究鲜有报道。为探究城市居民CO_(2)实时暴露特征与家庭个体差异,本研究以四川省32个城市居民家庭(111人)为研究对象,利用CO_(2)实时监测仪监测居民主要生活微环境(厨房、客厅、卧室、室外、办公室和车内)CO_(2)实时浓度,通过详细问卷调查获得居民24 h活动轨迹,绘制CO_(2)实时暴露曲线、分析家庭个体暴露差异、计算不同微环境对居民CO_(2)暴露贡献以及暴露强度。结果表明,13.5%的受试居民存在CO_(2)过度暴露风险(日均暴露浓度>1000 mg·L^(-1));所有受试居民均存在短期CO_(2)高浓度暴露风险,日内暴露于1000 mg·L^(-1)以上浓度累计时长为5.4~11.2 h。受试居民CO_(2)暴露特征存在显著的家庭个体差异。日均暴露浓度与年龄呈正相关,并且存在性别差异。老年、中年和儿童的日均暴露浓度分别为(781±387)、(709±403)和(693±385)mg·L^(-1)。家庭成员中,男童日均暴露浓度高于女童,而中年和老年群体中女性日均暴露浓度均高于男性,控制卧室、客厅、车内和厨房微环境中的CO_(2)浓度可有效减少居民个体CO_(2)暴露风险。本研究为居民CO_(2)实时暴露风险研究和过高浓度暴露风险防控提供参考数据。

CO_(2) is an important indicator of indoor air quality,and elevated indoor CO_(2) concentration can pose varied risks to human health.However,the residents’real-time CO_(2) exposure remains undefined.To explore the characteristics of real-time CO_(2) exposure in urban residents and the intra-individual variations of families,real-time monitors were used to collect CO_(2) concentration in different microenvironments(kitchen,living room,bedroom,outdoor,office and family vehicle)in 32 households in urban community of Sichuan Province.Total 111 residents were involved and the time of their stays in selected spaces were obtained through detailed questionnaires.The real-time CO_(2) exposure curves were drawn,the relative contribution and intensity of each microenvironment to residents’CO_(2) exposure were calculated.The results showed that 13.5%of the residents were at risk of excessive exposure to CO_(2),whose daily average exposure concentration were higher than the national standard limit of 1000 mg·L^(-1).All the tested residents had exposed to short-term high concentration CO_(2) over a period of 5.4~11.2 h daily.There were significant family and individual differences in the characteristics of CO_(2) exposure among the subjects.The average daily exposure CO_(2) concentration was positively correlated with the increase of the residents’age((693±385)mg·L^(-1) in children,(709±403)mg·L^(-1) in middle-aged adults,and(781±387)mg·L^(-1) in elderly).Among family members,the average daily exposure level of male children was significantly higher than that of female children,while the exposure level of female adults was higher than that of male adults.It is of great importance to maintain the CO_(2) level in living room,bedroom,kitchen and family vehicle under the threshold to lower the associated health risks.The study focused on the variations of CO_(2) exposure among family members and provided health strategies on lowering the CO_(2) excessive exposure.More public attention should be raised on the CO_(2) exposure characteristics between male and female at different age,and differentiated public health strategies should be introduced too.