Instituto Nacional de Salud Pública, Centro de Investigación en Salud Poblacional, Dirección de Salud Ambiental, México.
Universidad Autónoma Metropolitana, Unidad Iztapalapa, División de Ciencias Sociales y Humanidades, México.
Neurotoxicology. 2018 Jan;64:142-151. doi: 10.1016/j.neuro.2017.08.014. Epub 2017 Sep 10.
In the state of Hidalgo, Mexico, is found the largest second deposit of Manganese (Mn) in Latin America. Various studies on the sources of emission, exposure, and the effects on the health of children and adults have been conducted utilizing an ecosystem approach. Given the findings of Mn levels in air and the neurocognitive effects, an Environmental Management Program (EMP) was designed and implemented with the purpose of reducing exposure to Mn of the population, including various actions for reducing Mn emissions into the atmosphere.
To evaluate the impact of the EMP on the concentrations of Mn in air, as well as the modification of exposure to Mn in the blood and hair of adult residents of the communities intervened.
A quasi-experimental study was conducted in five rural communities, in which Mn concentrations were evaluated in air and in blood in the years 2002 and 2007, pre-intervention, and in 2013, postintervention. In 2003, the concentration of hair Mn among the communities was evaluated. Measurements were carried out of Particulate Matter (PM) of >10 and 2.5μm (PM10 and PM2.5), and Mn in PM10 and PM2.5 were measured using proton-induced X-ray emissions (PIXE). The method of Difference in Differences (DID) was applied to estimate the impact of EMP on Mn concentrations in particulate matter via linear regression through multilevel models. To evaluate the effect of Mn concentrations in air over Mn concentrations in blood in both study periods in the mining communities per year (2002 and 2013), a linear regression model for each year was employed.
We estimated that the EMP contributed to reducing the average daily concentrations of Mn in PM10 and PM2.5 by 92 and 85%, respectively. The adjusted model did not show an effect of Mn concentrations in air over Mn concentrations in blood in both study periods.
The results suggest that the measures implemented to reduce Mn emissions in air exerted a significant impact on the reduction of inhaled exposure in adult population.
在墨西哥伊达尔戈州，发现了拉丁美洲最大的第二大锰（Mn）矿床。利用生态系统方法对该地区的排放源、暴露情况以及对儿童和成人健康的影响进行了各种研究。鉴于空气中 Mn 含量和神经认知效应的研究结果，设计并实施了环境管理计划（EMP），目的是减少人群接触 Mn，包括采取各种行动减少向大气中排放 Mn。
评估 EMP 对空气中 Mn 浓度的影响，以及干预后社区成年居民血液和头发中 Mn 暴露程度的变化。
在五个农村社区开展了一项准实验研究，在干预前的 2002 年和 2007 年以及干预后的 2013 年，评估了空气中和血液中的 Mn 浓度。2003 年，评估了社区中头发中的 Mn 浓度。使用质子诱导 X 射线发射（PIXE）测量了>10μm 和 2.5μm 的颗粒物（PM10 和 PM2.5）中的 PM 以及 PM10 和 PM2.5 中的 Mn。应用差异中的差异（DID）方法，通过多水平模型中的线性回归，估计 EMP 对颗粒物中 Mn 浓度的影响。为了评估矿区社区每年（2002 年和 2013 年）两个研究期空气中 Mn 浓度对血液中 Mn 浓度的影响，我们为每一年建立了一个线性回归模型。
我们估计 EMP 有助于将 PM10 和 PM2.5 中 Mn 的日均浓度分别降低 92%和 85%。调整后的模型显示，两个研究期内空气中 Mn 浓度与血液中 Mn 浓度之间没有关系。
结果表明，为减少空气中 Mn 排放而采取的措施对减少成年人群的吸入暴露量产生了显著影响。
