Isocyanate Skin and Air Exposure: Assessment and Control

描述(申请人提供)：这是RO1提案的第二次修订，该提案旨在调查MDI织物涂层工厂的异氰酸酯皮肤和空气暴露，并实施现场干预计划以减少异氰酸酯皮肤暴露。反应性异氰酸酯被广泛用作生产聚氨酯的基本交联剂，50多年来一直是职业性哮喘的主要原因。直到最近，人们一直认为呼吸道是异氰酸酯暴露的关键途径，到目前为止，临床实践、研究和预防几乎完全集中在空气中暴露。越来越多的证据表明，异氰酸酯皮肤暴露会导致异氰酸酯哮喘的发生。尽管呼吸性异氰酸酯暴露减少，异氰酸酯哮喘仍在继续发生，通常在空气中测量水平低于监管标准的工作环境中，也存在皮肤暴露的机会。这项拟议的项目是一项现场干预研究，旨在评估和减少MDI氨纶织物涂层工厂中的异氰酸酯暴露，该工厂雇用了大约100名工人。这家工厂最近的一项健康调查显示，对MDI的敏感率很高，超过三分之一的工人检测到MDI免疫球蛋白，尽管MDI的空气水平基本上无法检测到。具体目标将是：目标1)使用基于定量空气和皮肤采样数据以及暴露的生物标志物的暴露算法来表征个体工人MDI呼吸和皮肤暴露的特征目标2)表征工人的健康状况和早期疾病的标志物目标3)设计和实施综合干预计划以减少异氰酸酯皮肤暴露目标4)评估干预计划的有效性该研究将包括对工人的呼吸和皮肤暴露、健康状况和选定的生物标志物的初步定量评估。随后将制定和实施综合干预计划，以减少MDI皮肤暴露。干预计划的有效性将通过比较干预前后的工作实践、MDI暴露和相关生物标志物来评估。这些发现将极大地扩展我们关于异氰酸酯皮肤暴露的知识，并确定减少此类暴露的有效策略。这些发现应该与越来越多的最终用途MDI聚亚安酯工作环境相关。 公共卫生相关性：异氰酸酯是生产大量聚氨酯泡沫塑料和其他产品所必需的广泛使用的化学品，仍然是职业性哮喘的主要原因。到目前为止，研究和控制主要集中在空气中的暴露。尽管空气水平降低，但暴露于空气中的工人仍会继续患上异氰酸酯哮喘。最近的研究表明，难以监测和控制的异氰酸酯皮肤暴露可能在异氰酸酯哮喘的发展中发挥重要作用。该项目将是一项现场干预研究，旨在评估一家聚氨酯涂料厂皮肤暴露于异氰酸酯的程度和对健康的影响，并确定减少这种暴露的有效战略。这一发现应该与数百万生产和使用聚氨酯产品的工人有关。

DESCRIPTION (provided by applicant): This is the second revision of a RO1 proposal to investigate isocyanate skin and air exposures in an MDI fabric coating factory and implement a field intervention program to reduce isocyanate skin exposures. Reactive isocyanates, widely used as the essential cross-linker for producing polyurethane, have been a leading cause of occupational asthma for over 50 years. Until recently it has been presumed that the respiratory tract is the key route of isocyanate exposure, with clinical practice, research and prevention to-date focused almost exclusively on airborne exposures. There is growing evidence that isocyanate skin exposure can contribute to the development of isocyanate asthma. Despite reduced respiratory isocyanate exposures, isocyanate asthma continues to occur, commonly in work environments where measured airborne levels are below regulatory standards, and also where there is opportunity for skin exposure. This proposed project is a field intervention study aimed at assessing and reducing isocyanate exposures in an MDI polyurethane fabric coating plant employing approximately 100 workers. A recent health survey at this plant showed a high prevalence of sensitization to MDI, with MDI IgG detected in over 1/3 of all workers, despite largely non-detectable MDI air levels. The Specific Aims will be to: Aim 1) Characterize baseline individual worker MDI respiratory and skin exposures using an exposure algorithm based on quantitative air and skin sampling data and biomarkers of exposure Aim 2) Characterize the health status of workers and markers of early disease Aim 3) Design and implement an integrated intervention program to reduce isocyanate skin exposures Aim 4) Evaluate the effectiveness of the intervention program The study will involve an initial quantitative assessment of the worker's respiratory and skin exposures, health status, and selected biomarkers. This will be followed by development and implementation of an integrated intervention program to reduce MDI skin exposures. The effectiveness of the intervention program will be evaluated by comparing work practices, MDI exposures, and relevant biomarkers before and after the intervention. The findings should substantially extend our knowledge concerning isocyanate skin exposure and identify effective strategies to reduce such exposures. The findings should be relevant to the growing number of end-use MDI polyurethane work settings. Public Health Relevance: Isocyanates, widely used chemicals essential to the production of numerous polyurethane foams and other products, remain a leading cause of occupational asthma. Research and controls to-date have focused largely on airborne exposures. Despite reduced air levels exposed workers continue to develop isocyanate asthma. Recent studies suggest that isocyanate skin exposures, which are difficult to monitor and control, may play an important role in the development of isocyanate asthma. This project will be a field intervention study aimed at assessing the extent and health impact of skin exposures to isocyanates in a polyurethane coating factory and also identifying effective strategies to reduce such exposures. The findings should be relevant to the millions of workers who produce and use polyurethane products.