ACID AEROSOL--RESPIRATORY EFFECTS IN INFANTS AND MOTHERS

动物和对照人类的研究表明，暴露在酸性环境中 气雾剂影响呼吸道反应性、粘液纤毛清除和肺功能 气流。初步数据显示，长期暴露在低水平 周围的酸性气溶胶可能与慢性肺部疾病有关， 尤其是支气管炎。美国环保局正在积极考虑环境保护 酸性气溶胶空气质量标准。这样的标准将启动一个 在方法上，主要的国家监管努力建立在几个基础上 弱小，学习。 酸性气溶胶与健康关系的流行病学研究 影响已经被明显的空间和时间所阻碍。 环境酸性气溶胶的可变性，室外低浓度， 混杂空气污染物的存在和评估的困难 曝光。人们一直认为，住宅室内暴露不会 有关于室内暴露的研究，但还没有。 我们已经确定无通风的煤油空间加热器是 室内酸性气溶胶。这些结果在现场测量中得到了证实。 考虑到受感染人数的潜力(1800万人 加热器已经在美国销售，它们是家庭供暖的主要来源 在一些国家)和接触水平，煤油加热器用户 会构成一个独特的群体，在这个群体中决定一个 酸性气溶胶暴露与呼吸健康影响之间的关系。 这项研究检验了暴露在高浓度环境中的假设 煤油造成的酸性和硫酸盐气溶胶空气污染物 使用加热器会增加急性或慢性上皮炎的风险 和6-24个月婴儿的下呼吸道症状(一种敏感的 人群)，包括咳嗽、痰、喘、流鼻水/鼻塞等。 假设接触不吸烟的婴儿的母亲也在 高峰期出现呼吸道症状和可逆性下降的风险增加 呼气流量也进行了测试。这些关联将被评估为 调整其他已知危险因素时的剂量反应关系 (环境烟草烟雾、二氧化氮、母亲吸烟、健康状况等)。 研究人群将从8700例活产中挑选出来 在延安医院度过了18个月的时间。接触过的婴儿(N=300)和 他们的不吸烟母亲(N=228)将住在使用煤油加热器的家庭中。 他们将与对照组的婴儿(N=600)进行比较，他们的 不吸烟母亲(N=456)在非采暖期间不使用煤油 季节包括婴儿和儿童的呼吸道症状报告 母亲和加热器的兼用。日最大流量差 为母亲在供暖和非供暖期间提供两周的时间 赛季将会被记录下来。嵌套暴露评估方案将是 现有的和潜在的混杂因素将得到控制。如果是季节性的 在症状发生率和肺功能测量方面发现了差异 此设计将允许区分曝光效果和 季节性变化的影响。 这项研究将对确定一个 酸性气溶胶需要环境空气质量标准来保护环境 公共卫生。它还将确定任何增加的健康风险 大量的煤油加热器用户。

Animal and controlled human studies indicate that exposure to acidic aerosol affect airway reactivity, mucociliary clearance and pulmonary airflow. Preliminary data suggests that long term exposure to low level ambient acidic aerosol may be associated with chronic lung disease, particularly bronchitis. The U.S. EPA is actively considering an Ambient Air Quality Standard for acidic aerosol. Such a standard would initiate a major national regulatory control effort based on a few, methodologically weak, studies. Epidemiologic studies of an association between acidic aerosol and health effects have been handicapped by the pronounced spatial and temporal variability of ambient acidic aerosol, the low outdoor concentrations, presence of confounding air contaminants and difficulties assessing exposures. It has been assumed that residential indoor exposures do not exist and not studies of indoor exposures have been done. We have identified unvented kerosene space heaters as a major source of indoor acidic aerosol. These results are confirmed in field measurements. Given the potential for the number of individuals exposed (18 million heaters have been sold in the U.S. and they are a major source of home heat in a number of countries) and the levels of exposure, kerosene heater users would constitute a unique population in which to determine the nature of an association between acidic aerosol exposure and respiratory health effects. This study tests the hypothesis that exposures to elevated concentrations of acidic and sulfate aerosol air contaminants, resulting from kerosene heater use are associated with an increased risk of acute or chronic upper and lower respiratory symptoms in infants age 6-24 months (a sensitive population), including cough, phlegm, wheeze, runny/stuffy nose, etc. The hypothesis that the nonsmoking exposed mothers of the infants are also at an increased risk of respiratory symptoms and reversible decrements in peak expiratory flow is also tested. these associations will be evaluated for a dose response relation while adjusting for other known risk factors (environmental tobacco smoke, NO2, maternal smoking, health status, etc.). The study population will be selected from 8,700 live deliveries occurring at YHN Hospital during a 18 month period. The exposed infants (N=300) and their nonsmoking mothers (N=228) will live in homes using kerosene heaters. They will be compared to a control group of infants (N=600) and their nonsmoking mothers (N=456) not using kerosene during the nono-heating season including reports of respiratory symptoms in both the infants and mothers and concurrent use of the heater. Diurnal peak flow differences for the mothers for a two week period during the heating and non-heating season will be recorded. A nested-exposure assessment protocol will be employed and potential confounding factors will be controlled. If seasonal differences are found for symptom rates and pulmonary function measurements this design will allow for a distinction between exposure effects and seasonal variation effects. This study will have important implications in determining whether an Ambient Air Quality Standard is needed for acidic aerosol to protect the public health. It will also identify any increased health risk for the large population of kerosene heater users.