Validation of Indirect Pesticide Exposure Estimates

描述(由申请人提供)： 因为通常情况下，致癌性接触之间相隔多年 而随后发生的癌症，流行病学家往往必须使用 间接估计研究参与者的历史暴露。早些时候 研究表明，有关农作物和相关杀虫剂的历史数据 应用可以用来估计农用杀虫剂的概率 生活在田野附近的人中的暴露，但这项追溯工作可能 没有确定附近的居民是否真的接触到了辐射。然而，a 从以下地点收集环境和生物样本的前瞻性研究 离农田不同距离的家庭会透露 清晰的曝光梯度是否作为距离 字段，以及2)指示测量的 基于记录的家庭成员农药暴露量预测方法 曝光。如果随着距离的增加而出现可预测的曝光梯度 从现场，那么追溯暴露估计可能会进一步 对此渐变进行了优化以解决此问题。我们建议研究除草剂 阿特拉津作为生活在玉米地附近人群中农药暴露的标志 在伊利诺伊州，附近有很多农村住房 玉米地，以及2)与 农业用地。为了确定特定的区域和特定的房屋，我们将 使用各种数据，包括：美国农业普查和 伊利诺伊州农业统计局，航空摄影和/或卫星 影像、地理信息系统数据集、本地化普查数据(区块、区块组和人口普查 区域级别)和地形图。我们从50个家庭中的每一个 报名，我们将包括一名成人和一名4岁以下的儿童 我们将获得尿液样本；我们还将获得房屋灰尘样本和 每家每户的饮用水样本。调查问卷将捕获信息 关于行为和住房特征可能影响 参与者的农药剂量。这项拟议的研究将有助于揭示 基于记录的技术将有助于重建农药暴露情况 以及使用额外的暴露相关变量是否会增加 暴露估计的精确度。

DESCRIPTION (provided by applicant): Because many years typically elapse between etiologic carcinogenic exposures and the subsequent occurrence of cancer, epidemiologists often must use indirect estimates of historical exposures for study participants. Earlier work suggests that historical data on crops and associated pesticide applications can be used to estimate the probability of agricultural pesticide exposures among persons living near fields, but this retrospective work could not ascertain whether nearby residents actually were exposed. However, a prospective study that collects environmental and biological samples from households at different distances from agricultural fields would 1) reveal whether a clear exposure gradient occurs as a function of distance from the fields, and 2) indicate whether there is a correspondence between measured exposures and a records-based method for predicting household member pesticide exposures. If a predictable exposure gradient occurs with increasing distance from the fields, then retrospective exposure estimates could be further refined to account for this gradient. We propose to study the herbicide atrazine as a marker of pesticide exposure in persons living near corn fields in Illinois in areas with 1) pockets of rural housing located in proximity to cornfields, and 2) towns and communities that lie in juxtaposition to agricultural lands. To identify specific areas and specific houses, we will use a variety of data including: the U.S. Census of Agriculture and the Illinois Agricultural Statistics Service, aerial photography and/or satellite imagery, GIS data sets, localized census data (block, block group and census tract levels), and topographic maps. From each of the 50 households that we enroll, we will include one adult and one child younger than 4 years from whom we will obtain a urine sample; we will also obtain a house dust sample and drinking water sample from each home. A questionnaire will capture information about behaviors and housing characteristics that might influence the participants' pesticide dose. The proposed study will help reveal whether records-based techniques will be useful for reconstructing pesticide exposures and whether the use of additional exposure-related variables increases the precision of the exposure estimates.