Analysis of methyl tert-butyl ether in urine of primary school students in Beijing

Abstract

Objective To investigate the urine methyl tert-butyl ether (MTBE) level of a primary school students in Chang- ping District, Beijing, and analysis the effect factors, give the advice if the MTBE is eligibility as an exposure biomarker of automobile exhaust.

Methods Using the panel study, randomly selected 20 sixth-grade students (10 male and 10 female) from Zhixing School in Changping district, Beijing, from June 7th to 13th, 2018. All participants completed a questionnaire for collecting demographic and geographic information and daily activities. All participants were given guidance to repeatedly collected urine samples 3 times (8: 00, 11: 00 and 16: 00 instant urien) a day for 7 days, totally 420 urine samples were collected. Urine MTBE were measured and the statistic significant of the Urine MTBE at different groups were evaluated.

Results MTBE were detected in all 420 urine samples of primary school students, the geometric mean of creatinine-corrected MTBE exposure level in 8: 00, 11: 00 and 16: 00 instant urine were 0.12, 0.12 and 0.12 mg/g creatinine, respectively. Urine MTBE concentration was statistical significant in different daily outdoor activity time, the distance of home address to the main road, and daily use time of air purification equipment in class ( P =0.00, 0.04, 0.00).

Conclusion There was a universal MTBE exposure among students in a primary school in Beijing, and the impact factors to exposure level were daily outdoor activity time, distance from home address to the closest main road, and daily use time of air purification equipment in class. This result indicate MTBE may be a valuable candidate for exposure biomarker of automobile exhaust, and more research should be done.

Abstract

【摘要】 目的 了解北京市昌平区小学生尿中甲基叔丁基醚 (methyl tert-butyl ether, MTBE) 的暴露水平及其影响因 素, 为评价 MTBE 作为小学生汽车尾气内暴露生物标志物的可行性提供线索。 方法 采用定群研究的设计方法, 于 2018 年 6 月 7—13 日连续 7d (每天 3 次, 分别为 8:00、11:00 和 16:00, 包括工作日和休息日) 对从昌平区智星学校随机抽取的 20 名六年级学生 (男、女各 10 名) 进行尿样采集, 共收集尿样 420 份, 测定其中MTBE水平。通过问卷获取小学生基本信 息与日常活动情况。 结果 420 份尿样均检出 MTBE。经过校正, 小学生 8:00、11:00 和 16:00 的即时尿中MTBE暴露水平 的几何均数分别为 0.12, 0.12, 0.12 mg/g 肌酐。暴露水平分别按室外活动时间、家是否靠近主干道、所在班级每天使用空 气净化设备时间分组时, 组间差异有统计学意义 ( P 值分别为 0.00, 0.04, 0.00)。 结论 北京市某小学学生存在MTBE普遍 暴露, 尿中 MTBE 暴露水平的影响因素有家是否靠近交通主干道、每日室外活动时间、班级每日使用空气净化设备时间。有必要对尿 MTBE 作为汽车尾气暴露内标志物开展更深人研究。