Estimating Dioxin Exposure from Indoor Woodsmoke and the Burning of Plastics

描述（由研究者提供）：用于烹饪和取暖的木材是世界上大部分人口的基本燃料。做饭和取暖通常是在室内使用效率低的无通风口的炉子，使许多人暴露在高浓度的木材烟雾中。烟雾的成分包括不完全燃烧产生的数百种化合物，其中许多是有毒的，甚至是致癌的。二恶英和呋喃是世界上毒性最大的物质之一，在木材燃烧过程中与其他数百种化合物沿着形成。以每单位燃料质量的二恶英/呋喃比较，木柴燃烧所排放的二恶英浓度低于工业废物处理过程所排放的二恶英浓度。然而，一个人在厨房用明火做饭时吸入的二恶英/呋喃的实际数量估计要高得多。对一名在明火上做饭的妇女每日摄入量的粗略估计得出的摄入量在二恶英和呋喃的国际限值范围内。过去八年来，我们一直在危地马拉农村高地研究烹饪产生的室内木材烟雾的影响。这项研究提供了大量关于木材烟雾影响的信息，以及改进炉灶作为干预措施的成功。在危地马拉逗留期间，我们注意到在火中加入塑料作为废物处理手段的做法，因为在这些贫困地区没有垃圾处理设施。焚烧垃圾的做法在世界各地都很普遍，特别是在已经燃烧室内生物质烟雾的贫困地区。添加塑料可能会增加二恶英的浓度，从而使更多人接触到剧毒化合物。为了更好地估计由于木材和塑料烟雾导致的二恶英暴露风险的数量级，我们将量化二恶英的浓度。我们将首先进行一系列基于实验室的室实验，以完善现场采样技术以及化学分析。然后，我们将测量二恶英浓度在一个典型的危地马拉乡村厨房从木材和塑料燃烧在不同的比例。使用这些数据和调查塑料燃烧沿着与厨房颗粒物浓度，和个人暴露于室内空气污染收集从我们以前的两个研究在同一地区，我们将估计二恶英暴露从木材烟雾和可能增加的浓度从塑料燃烧。这项研究将提供一个更准确的估计二恶英暴露于木材和塑料燃烧，并可能突出暴露于大量人口的一种极毒污染物。 公共卫生相关性：二恶英被认为是人类已知的最危险的化学品之一，量化与室内烹饪有关的木材和塑料烟雾的暴露量可能会揭示已经承受严重贫困的人们的大量先前未测量的暴露量。

DESCRIPTION (provided by investigator): Wood for cooking, and heating is an essential fuel to a large portion of world's population. Often cooking and space heating occurs on inefficient unvented stoves indoors exposing many to very high concentrations of wood smoke. The components of the smoke include hundreds of compounds created from incomplete combustion, many of which are toxic and even carcinogenic. Dioxins and furans, some of the most toxic substances in the world, are formed in wood combustion along with the other hundreds of compounds. The concentrations of dioxins emitted from a wood fire are lower than those from an industrial waste process when compared on a dioxin/furan per unit fuel mass basis. However an estimation of the actual quantity of dioxins/furans inhaled by a person in a kitchen cooking over an open fire is much higher. A rough estimation of the daily intake fraction of a woman, who cooks over an open fire yielded an intake that was in the range of international limits for dioxins and furans. We have been studying the impacts of indoor wood smoke from cooking for the past eight years in the rural highlands of Guatemala. This research has provided a wealth of information about the impacts of wood smoke and the success of an improved stove as an intervention. During the time spent in Guatemala we have noticed the practice of adding plastic to a fire as means of waste disposal as trash disposal is not available in such poor areas. The practice of burning trash is commonplace worldwide, especially in poor areas already burned with indoor biomass smoke. The addition of plastic may increase the concentrations of dioxins creating an even larger exposure to extremely toxic compounds. In order to better estimate the order of magnitude of the risk from dioxin exposure due to wood and plastic smoke we will quantify the concentrations of dioxins. We will first conduct a series of lab based chamber experiments to perfect a field sampling technique, as well as the chemical analysis. Then we will measure dioxin concentrations in a typical Guatemalan village kitchen from both wood and plastic combustion at varying ratios. Using this data and surveys on plastic burning along with kitchen particulate matter concentrations, and personal exposures to indoor air pollution collected from our two previous research studies in the same area, we will estimate dioxin exposure from wood smoke and the possibly increased concentrations from plastic burning. This study will provide a more accurate estimate of dioxin exposure from wood and plastic combustion, and possibly highlight an exposure to a large population of a extremely toxic pollutant. PUBLIC HEALTH RELEVANCE: Dioxins are considered to be one of the most dangerous chemical known to man. Quantifying exposures from wood and plastic smoke associated with indoor cooking may reveal a large previously unmeasured exposure to people already burdened with the severity of poverty.