College of Medicine, Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267, USA.
Sci Total Environ. 2012 Jun 15;427-428:19-25. doi: 10.1016/j.scitotenv.2012.03.037. Epub 2012 May 1.
Airborne exposure to manganese (Mn) can result in neurologic effects. Stationary air sampling is the traditional technique to assess Mn exposure for communities, yet may not accurately reflect children's personal exposure. The goal of the study was to characterize personal exposure to Mn and PM(2.5) in a cohort of children ages 7-9 years residing near a ferromanganese refinery. A subset of children living in non-smoking households ages 7-9 enrolled in the Marietta Community Actively Researching Exposure Study during March-June 2009 and 2010 were invited to participate. Blood and hair were collected and analyzed for Mn. Participants wore a PM(2.5) sampler (Personal Modular Impactor) for 48 h. TWD was based on time spent at home and school and the distance of each from the refinery. Stationary outdoor air sampling was conducted 8 km from the refinery using a Harvard-type PM(2.5) impactor. The relationship between personal Mn exposure and TWD was examined by multiple regression adjusting for stationary air Mn concentration, wind speed and direction, and precipitation. Complete personal air sampling data were collected on 38 children. TWD ranged from 4.7 km to 28.5 km with a mean distance of 11.1 (4.7 sd) km. Mn concentration in personal air samples ranged from 1.5 ng/m3 to 54.5 ng/m3 (geometric mean, 8.1 ng/m3). TWD was a significant predictor of natural log personal air Mn concentration (lnMn) with an associated decrease of 0.075 lnMn for each km TWD (p<0.05, 95% CI -0.13 to -0.01). Personal Mn exposures were positively associated with stationary air Mn levels and inversely associated with wind speed. A child's location (home and school) relative to the refinery is a significant predictor of personal Mn exposure. Wind speed is also an important contributor to personal Mn exposure.
空气中的锰（Mn）暴露可导致神经系统影响。固定空气采样是评估社区 Mn 暴露的传统技术，但可能无法准确反映儿童的个人暴露情况。本研究的目的是描述居住在锰铁合金精炼厂附近的 7-9 岁儿童的个人 Mn 和 PM（2.5）暴露情况。2009 年 3 月至 6 月期间，马里埃塔社区主动研究暴露研究（Marietta Community Actively Researching Exposure Study）邀请了居住在非吸烟家庭中的部分 7-9 岁儿童参加。采集了血液和头发样本并进行了 Mn 分析。参与者佩戴了 PM（2.5）采样器（个人模块化冲击器）48 小时。总每日暴露量（TWD）基于在家和学校的时间以及从精炼厂的距离。在距离精炼厂 8 公里处使用哈佛型 PM（2.5）冲击器进行了固定室外空气采样。通过多元回归调整固定空气 Mn 浓度、风速和风向以及降水量，检验了个人 Mn 暴露与 TWD 之间的关系。对 38 名儿童进行了完整的个人空气采样。TWD 范围为 4.7 公里至 28.5 公里，平均距离为 11.1（4.7 sd）公里。个人空气样本中的 Mn 浓度范围为 1.5 ng/m3 至 54.5 ng/m3（几何平均值，8.1 ng/m3）。TWD 是个人空气 Mn 浓度自然对数（lnMn）的重要预测因子，每公里 TWD 下降 0.075 lnMn（p<0.05，95%置信区间-0.13 至-0.01）。个人 Mn 暴露与固定空气 Mn 水平呈正相关，与风速呈负相关。儿童相对于精炼厂的位置（家庭和学校）是个人 Mn 暴露的重要预测因子。风速也是个人 Mn 暴露的重要因素。
