AGRICULTURAL DUST AND CHILDHOOD ASTHMA SYMPTOMS

描述(申请人提供)：这项拟议的研究将评估在北卡罗来纳州公立学校就读的7年级和8年级学生中，接触工业畜牧业与哮喘相关症状流行之间的关系。1999-2000学年，北卡罗来纳州卫生与公众服务部在全州范围内对中学生进行了一项以人群为基础的调查，以评估哮喘相关症状、药物使用、充分药物使用的障碍以及报告症状的行为后果的患病率。这项申请旨在通过探索接受调查的学生中哮喘症状的患病率与在校期间接触农业空气污染物之间的关系，扩大全州调查的益处和实用性。将使用工业畜牧业操作的广泛数据库来估计基于学校的接触情况，包括有关大小、动物类型、地理位置和废物管理做法的信息。暴露估计将补充提供有关学校环境的信息，包括空调、霉菌、气味和其他学校建筑特征。流行病学分析将侧重于哮喘相关症状的流行与暴露估计之间的联系。这项研究的具体目的是：(1)通过空间分析估计公立中学工业畜牧业排放的空气污染物：(A)从畜牧业到中学的距离，(B)某所中学周围畜牧业中所有动物的稳态活重，以及(C)从学校工作人员那里获得的关于学校气味、环境和身体状况的信息；(2)确定学生患哮喘相关症状的风险是否与距离最近的工业畜牧业、学校附近的动物数量和学校接触工业牲畜有关；以及(3)评估与哮喘相关的症状和暴露在地理、种族和社会经济类别中的分布，以确定症状和牲畜暴露的频率和严重程度是否对特定学生亚群造成最沉重的负担。

DESCRIPTION (provided by applicant): The proposed study will assess the relationship between exposure to industrial livestock operations and the prevalence of asthma-related symptoms among 7TH and 8TH grade students attending public schools in North Carolina. During the 1999-2000 school year, the North Carolina Department of Health and Human Services conducted a statewide population-based survey of middle school students in order to assess the prevalence of asthma-related symptoms, medication use, barriers to adequate medication use, and behavioral consequences of the reported symptoms. This application seeks to extend the benefit and utility of the statewide survey by exploring the relationship between the prevalence of asthma symptoms among surveyed students and exposure to agricultural airborne pollutants experienced during school hours. School-based exposure will be estimated using an extensive database of industrial livestock operations, including information about the size, type of animals, geographic location, and waste management practices. Exposure estimates will be supplemented with information provided about the school environment, including air-conditioning, mold, odor, and other school-building characteristics. Epidemiologic analyses will focus on the association between the prevalence of asthma-related symptoms and exposure estimates. The specific aims of this study are: (1) to estimate exposure to airborne emissions from industrial livestock operations at public middle schools using spatial analysis of the following measurements: (a) distance from the livestock operation to the middle school, (b) steady state live weight of all animals in livestock operations surrounding a given middle school, and (c) information obtained from school personnel about odor, environmental, and physical conditions at the schools; (2) to determine whether students' risk of asthma-related symptoms is related to the distance to the nearest industrial livestock operation, quantity of animals near the school, and school-based exposure to industrial livestock; and (3) to evaluate the distribution of asthma-related symptoms and exposures within geographic, racial, and socio-economic categories to determine whether the frequency and severity of symptoms and livestock exposures most heavily burden specific subpopulations of students.