PAH Exposure and DNA Damage in Roofers

描述(由申请人提供)：建筑业是最常见的与职业癌症有关的行业之一，屋顶工人报告的癌症风险较高。接触致癌的多环芳烃(PAHs)一直是该行业的主要担忧，主要是接触沥青烟雾和煤焦油的工人。这一领域的大多数流行病学研究都因缺乏具体的定量暴露数据和对吸烟等混杂因素的考虑不足而受到批评。据估计，50,000名屋顶工人在平均40%的工作时间内暴露在沥青烟雾中。佛罗里达州是屋顶工人密度最高的州，占美国所有屋顶工人的近10%。然而，还没有研究调查这一群体中沥青暴露及其相关的健康风险。拟议研究的目的是同时量化南佛罗里达州屋顶工人暴露于多环芳烃(个人和区域测量)、其内部剂量(血液中的多环芳烃和尿液中选定的代谢物)和DNA损伤(使用具有自动图像捕获和无偏见评分的彗星分析)。有关工作和任务相关因素、个人防护设备的使用和非职业性接触的信息将通过问卷调查和在工作期间观察屋顶工人来收集。多元线性回归模型将被用来调查生物标记物和DNA损伤的变异来源。拟议研究的创新方面包括使用基于萘的生物标记物来提高分析技术的灵敏度和实用性，在自动图像捕获和无偏彗星分析方面应用新进展，以及在南佛罗里达州屋顶工人中实现暴露、内部剂量和癌症风险标记物之间的直接联系。这项拟议的研究是专门为应对国家职业健康研究所(NIOSH)、国家职业研究议程(NORA)部门的研究空白而设计的，它将回应建筑部门暴露评估和生物监测研究优先领域的需求。拟议的研究将通过提供有关改变工作场所暴露水平的因素的信息，为NIOSH指导的“从研究到实践的努力”做出贡献。我们预计，这一结果将指导未来的战略，以减少和防止屋顶工人接触多环芳烃。 公共卫生相关性：以前的研究报告称，接触沥青的屋顶工人患癌症的风险增加；然而，研究未能衡量每个工人暴露在沥青中的风险。使用尿中的萘代谢物作为沥青中化学物质的替代品，我们建议测量南佛罗里达州屋顶工人接触沥青及其与DNA损伤的潜在联系。将调查几个与工作、任务和生活方式有关的因素(如吸烟)对接触水平和DNA损伤的贡献。

DESCRIPTION (provided by applicant): Construction is among the top industries most commonly linked to occupational cancers with elevated cancer risks being reported in roofers. Exposure to the carcinogenic polycyclic aromatic hydrocarbons (PAHs) has been a major concern in this industry, mainly in workers exposed to asphalt fumes and coal tar. Most epidemiology studies in this area have been criticized for lack of specific quantitative exposure data and inadequate consideration of confounding factors such as cigarette smoking. It is estimated that 50,000 on-roof workers are exposed to asphalt fumes during on average 40% of their working hours. The State of Florida has the highest concentration of roofers accounting for almost 10% of all roofers in the U.S. However, no studies have investigated asphalt exposure and the related health risks in this group. The objective of the Proposed Research is to simultaneously quantify exposure to PAHs (personal and area measurements), their internal dose (PAHs in blood and selected metabolites in urine) and DNA damage (using the Comet assay with an automatic image capture and un-biased scoring) in South Florida roofers. Information on work and task related factors, use of personal protective equipment and non-occupational exposures will be collected via questionnaires and also by observing the roofers during work. Multiple linear regression models will be applied to investigate the sources of variation in biomarkers and DNA damage. The innovative aspects of the Proposed Study are the use of naphthalene-based biomarkers to increase sensitivity and practicality of analytical techniques, the application of new advances in the automatic image capture and un- biased Comet assay, and the achievement of a direct linkage between exposure, internal dose and cancer risk marker among roofers in South Florida. The Proposed Study is uniquely designed to respond to research gaps in the National Institute of Occupational Health (NIOSH) National Occupational Research Agenda (NORA) sectors and it will respond to needs in exposure assessment and biomonitoring research priority areas for the construction sector. The Proposed Research will contribute to the NIOSH guided 'research to practice efforts' by providing information on factors altering exposure levels at the workplace. We expect that results will guide future strategies to reduce and prevent PAH exposures in roofers. PUBLIC HEALTH RELEVANCE: Previous studies have reported increased cancer risk among roofers who are exposed to asphalt; however studies have failed to measure asphalt exposures for each worker. Using naphthalene metabolites in urine as a surrogate for the chemicals in asphalt, we propose to measure asphalt exposure and its potential link to DNA damage in South Florida roofers. The contribution of several work, task and lifestyle related factors (e.g. smoking) on the levels of exposure and DNA damage will be investigated.