Collaborative Research: Phthalate Plasticizers: Temperature Dependence of Material/Air Equilibria and Consequences for Emissions, Exposure and Risk

合作研究：邻苯二甲酸酯增塑剂：材料/空气平衡的温度依赖性以及对排放、暴露和风险的影响

• 批准号: 1066802
• 负责人: John Little
• 金额: $ 27.24万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1066802&HistoricalAwards=false
• 关键词: Collaborative; Research; Phthalate; Plasticizers; Temperature

PIs: John Little / Ying XuProposal Numbers: CBET-1066802 / 1066642Institutions: Virginia Tech / Univ. of Texas-AustinTitle: Collaborative Research: Phthalate Plasticizers: Temperature Dependence of Material/Air Equilibria and Consequences for Emissions, Exposure and RiskModern indoor environments contain a vast array of manufactured materials, many of which emit toxic contaminants. Of special concern are indoor levels of phthalate plasticizers, which have increased substantially in recent decades. These semi-volatile organic compounds (SVOCs) enhance product performance, and are ubiquitous, redistributing from their original sources to indoor air, and subsequently to all interior surfaces. Because they partition so strongly to surfaces, many SVOCs persist for years after the source is removed. Biomonitoring (measuring concentrations in blood and urine) provides direct evidence of the virtually universal human exposure to plasticizers, which may result in profound and irreversible changes in the development of the reproductive tract. A recent report by the National Academies urgently recommends that the most important sources of phthalate exposure be identified. While biomonitoring alone cannot provide this answer, the PIs have developed and validated a fundamental approach that can be used to identify the most important sources of exposure to plasticizers. Building on this promising conceptual leap in understanding, their research objectives are to: (1) Select several indoor polyvinyl chloride products (PVCPs) based on the measured concentration of different phthalates present in the materials (C0); (2) Develop a novel, direct, solid-phase microextraction (SPME) method to measure (y0) the gas-phase concentration in equilibrium with C0, and use the resulting C0 vs y0 data to establish the nature of the equilibrium relationship as a function of temperature; (3) Characterize emissions of the target phthalates from nine of the selected PVCPs and validate their emissions model for the new phthalates in chamber experiments over a range of temperatures; (4) Extend the chamber approach to simultaneously measure emissions from two sources of phthalates (with each material acting as a sink for the phthalate from the other material); (5) Test the effect of temperature on phthalate emissions, sorption and condensation in vehicles under controlled conditions, and compare the results with analogous chamber studies; and (6) Use the measured/predicted y0 values to estimate screening-level exposure for the entire range of PVCPs studied and combine exposure with toxicity from ToxCast? to get risk, providing a simple method for the rapid prioritization of indoor sources most harmful to human health. This research builds on the first successful elucidation of the fundamental mechanisms governing the release of phthalates from polymer materials. The PIs will, for the first time, develop an innovative new SPME method to measure y0; establish the equilibrium relationship between C0 and y0 as a function of temperature; and test the temperature effect on phthalate emissions and sorption in cars and homes. The temperature effect could be of great significance when sunlight shines directly on a PVCP surface in a room or car, increasing the emission rate by orders of magnitude. When a person enters a hot car and turns on the air conditioning without opening the windows, the cooling phthalate vapor will condense, coating interior surfaces, including human skin, with a thin film of liquid phthalate, imposing potentially significant health risks. The PIs also will develop a powerful yet simple screening-level exposure assessment approach for PVCPs, and substantially enhance our ability to predict exposure (via inhalation, dermal sorption and oral ingestion of dust) to all phthalate plasticizers. Their fundamental approach to predict exposure to phthalates in PVCPs can almost certainly be generalized to a wide range of other SVOCs (PBDEs, organotins, and pesticides) emitted from a host of materials and products found in homes, cars, schools, offices, and factories. The new mechanistic understanding will enable the conscious design of green materials because the chemical and material properties that govern emissions are clearly understood. Diversity will be inculcated through their ACE (Academic Credit for Experimentation) program, as well as through personal relationships with colleagues at three HBCUs. The undergraduate ACE students at Virginia Tech will estimate exposure to some of the PVCPs in their own homes, enabling identification of new phthalate-laden PVCPs entering the market as well as some of the ?legacy? products that are no longer produced. Given that most PVCPs emit phthalates for decades, this constitutes a vital aspect of the project. The undergraduate students at UT Austin will be engaged in the first temperature controlled tests of automobile cabins. Their approach for estimating screening-level health risks can be used to prioritize cost-effective action, and could revolutionize how human health effects of indoor materials are evaluated.

PIS：John Little / Ying Xuproposal数字：CBET-1066802 / 1066642INSTITUTYS：VIRGINIA TECH / UNIV。德克萨斯 - 奥斯塔特尔（Texas-Austintitle）：合作研究：邻苯二甲酸酯增塑剂：材料/空气平衡的温度依赖性以及对排放，暴露和风险室内环境的后果包含大量制造物质，其中许多材料发出了有毒污染物。 特别令人担忧的是室内水平的邻苯二甲酸酯增塑剂，它们在近几十年来大大增加了。 这些半挥发性有机化合物（SVOC）可以增强产品性能，并且无处不在，从原始来源重新分布到室内空气，然后再分配给所有内部表面。 由于它们非常强烈地分配给表面，因此许多SVOC持续了多年，删除了来源。 生物监测（测量血液和尿液的浓度）提供了几乎普遍接触增塑剂的普遍暴露的直接证据，这可能会导致生殖道发展的深刻和不可逆转的变化。 美国国家科学院的最新报告急切地建议确定邻苯二甲酸盐暴露的最重要来源。 尽管仅生物监测无法提供此答案，但PIS已经开发并验证了一种基本方法，该方法可用于识别最重要的接触塑料来源。 在这种有希望的概念上的理解中，他们的研究目标是：（1）基于材料中存在的不同邻苯二甲酸盐的测量浓度（C0）选择几种室内聚氯化物产物（PVCP）； （2）开发一种新型，直接的，固相微萃取（SPME）方法，以测量（Y0）与C0平衡中的气相浓度，并使用所得的C0 VS Y0数据来确定平衡关系的性质，以作为温度的函数； （3）表征了从选定的PVCP的九个邻苯二甲酸酯的排放，并在一系列温度下验证腔室实验中新邻苯二甲酸盐的排放模型； （4）扩展了从两个邻苯二甲酸盐来源（每种材料用作邻苯二甲酸盐的水槽）同时测量排放的腔室方法； （5）测试温度对受控条件下车辆中邻苯二甲酸酯排放，吸附和凝结的影响，并将结果与​​类似的腔室研究进行比较； （6）使用测量/预测的Y0值来估计所研究的整个PVCP范围的筛选级别的暴露，并将暴露与Toxcast的毒性相结合？为了获得风险，提供一种简单的方法，可以快速对最有害人类健康有害的室内资源进行优先考虑。这项研究是基于首次成功阐明了控制邻苯二甲酸酯从聚合物材料中释放的基本机制。 PI首次将开发一种创新的新SPME方法来测量Y0。建立C0和Y0之间的平衡关系随温度的函数；并测试汽车和房屋中邻苯二甲酸盐排放和吸附的温度影响。 当阳光直接在房间或汽车的PVCP表面上发光，从而增加了数量级的排放速率时，温度效应可能具有重要意义。 当一个人进入热车并在不打开窗户的情况下打开空调时，冷却邻苯二甲酸酯蒸气会凝结，涂有涂层的内部表面，包括人皮，并带有液态邻苯二甲酸盐的薄膜，施加了潜在的重大健康风险。 PI还将为PVCP开发强大而简单的筛选水平暴露评估方法，并大大提高了我们预测所有邻苯二甲酸酯增塑的暴露（通过吸入，真皮吸附和口服粉尘）的能力。 他们预测PVCP中邻苯二甲酸盐暴露的基本方法几乎​​可以肯定地被推广到从房屋，汽车，学校，办公室和工厂中发现的许多材料和产品中发出的其他SVOC（PBDES，Organotins和Organtins和Ofnicides）。 新的机械理解将使绿色材料有意识地设计，因为对排放的化学和材料特性清楚地理解。 多样性将通过其ACE（实验学术学分）以及与三个HBCUS同事的个人关系来灌输多样性。 弗吉尼亚理工大学的本科生ACE学生将估计自己家中的一些PVCP接触，从而确定进入市场的新型PVCP以及一些“传统”？不再生产的产品。 鉴于大多数PVCP数十年来发出邻苯二甲酸酯，这构成了该项目的重要方面。 UT Austin的本科生将参与汽车舱的首次温度控制测试。 他们估算筛查水平健康风险的方法可用于优先考虑具有成本效益的行动，并可以彻底改变室内材料对人的健康影响。