UNS: Organophosphates and Phthalates in Sleep Microenvironments: Emission, Transport, and Infants' Exposure

1512610xu现代室内环境中含有大量的工业产品，其中许多产品会释放有毒污染物，对儿童有害。特别值得关注的是婴儿床床垫，因为婴儿大部分时间都在睡觉，他们的呼吸区和皮肤靠近或接触污染源，因此很可能暴露在高浓度的释放化学物质中，包括有机磷和邻苯二甲酸盐。虽然与接触这些半挥发性有机化合物有关的不良健康影响已得到广泛证明，但由于对这些半挥发性有机化合物在睡眠微环境中的排放和命运了解不足，对婴儿接触和随后的健康影响的准确评估仍然受到阻碍。本研究的目的是明确阐明与睡眠微环境中有机磷酸盐和邻苯二甲酸盐相关的排放、运输和婴儿暴露的基本机制。该项目将阐明控制婴儿床床垫中有机磷和邻苯二甲酸盐释放的基本机制，并将这些机制纳入新的运输和暴露模型。该项目将率先开发一种通用和快速的方法来测量控制半挥发性有机排放的关键参数，这对于快速筛选对儿童健康危害最大的半挥发性有机添加剂产品是迫切需要的。PI还将使用创新的直接方法精确测量半挥发性有机气体/颗粒分配。这项研究将首次将对排放的机理理解与之前被忽视的空气中颗粒、床上材料和皮肤的强吸收以及随后对吸入和皮肤暴露的影响联系起来。它将大大提高预测一系列化学品在睡眠微环境和其他类似微环境（如婴儿保育箱）中的排放、命运和运输以及暴露的能力，这些环境尚未就接触有毒化学品进行广泛研究。具体的研究目标是：1)开发一种新的、快速的方法来表征婴儿床床垫中有机磷酸盐和邻苯二甲酸盐的排放；2)通过系统的实验室研究确定目标半挥发性有机化合物与颗粒和表面（如床上用品和衣服）的吸附相互作用；3)建立创新的综合排放、运输和暴露模型，以预测睡眠婴儿附近污染物的时空分布和随后的暴露；4)在一个房间大小的室内，用婴儿呼吸热人体模型进行一系列的对照试验，以验证模型，并研究各种环境因素对婴儿暴露的影响。该项目将受益于与儿童环境卫生研究所的合作，并承诺共同组织一次专题讨论会，将项目的研究结果转交给大批保健研究人员和从业人员。

1512610XuModern indoor environments contain a vast array of manufactured products, many of which emit toxic contaminants that can harm children. Of special concern are crib mattresses, as infants spend most of their time sleeping, with their breathing zone and skin in close proximity to, or touching, the source, and thus are likely to be exposed to elevated concentrations of released chemicals, including organophosphates and phthalates. Although the adverse health effects associated with exposure to these semi-volatile organic compounds have been extensively demonstrated, accurate evaluation of infants' exposure and the subsequent health effect remain hamstrung by a poor understanding of the emission and fate of these semi-volatile organic compounds in sleep microenvironments. The goal of this research is to explicitly elucidate the fundamental mechanisms governing emission, transport, and infants' exposure associated with organophosphates and phthalates in sleep microenvironments.This project will elucidate the fundamental mechanisms that govern the release of organophosphates and phthalates from crib mattresses and incorporate these mechanisms into a new transport and exposure model. The PI will be the first to develop a general and rapid method for measuring key parameters that control semi-volatile organic emissions, which is urgently needed for rapid screening of products for semi-volatile organic additives that are most harmful to children's health. The PI will also accurately measure semi-volatile organic gas/particle partitioning using an innovative direct approach. This research will, for the first time, connect the mechanistic understanding of emissions to the previously-overlooked strong sorption by airborne particles, bedding materials, and skin, and to the subsequent impacts on inhalation and dermal exposures. It will significantly advance the ability to predict emission, fate and transport, and exposures for a range of chemicals in sleep microenvironments and other similar microenvironments (e.g., infants' incubators), which have not been extensively researched with respect to exposure to toxic chemicals. The specific research objectives are to: 1) develop a novel, rapid method to characterize the emissions of organophosphates and phthalates from crib mattresses; 2) determine the sorptive interactions of the target semi-volatile organic compounds with particles and surfaces (e.g., bedding and clothing) through systematic laboratory studies; 3) develop an innovative combined emission, transport, and exposure model to predict the spatial and temporal distributions of pollutants in the vicinity of sleeping infants and subsequent exposures; and 4) conduct a series of controlled tests in a room-sized chamber with a breathing, thermal manikin of an infant to validate the model and to investigate the influences of various environmental factors on infants' exposures. The project will benefit from collaboration with the Children's Environmental Health Institute, with commitment for co-organizing a symposium that will involve the transfer of the project findings to a large base of health researchers and practitioners.