Exposure To Polycyclic Aromatic Hydrocarbons And Male Sperm Quality

多环芳烃（PAHs）是最普遍存在的环境污染物之一。人类经常暴露于各种来源的复杂混合物中。越来越多的动物研究证据表明，燃料燃烧过程的副产品多环芳烃会导致雄性大鼠精子功能障碍。同时，基于有限的流行病学研究结果，多环芳烃对人类男性精子的影响尚无定论。我们建议进行一项纵向研究，以评估多环芳烃对人类受试者男性精子的影响。核心假设是多环芳烃暴露导致焦炉工人精子质量下降。我们的具体目标是：(1)评估焦炉工人的精子质量；ii)确定精子染色质完整性与多环芳烃生物标志物之间的相关性；iii)通过识别特定的DNA损伤来确定精子氧化损伤。纵向研究包括重复测量，以解释多环芳烃暴露，因为它与精子发生过程中对精子的毒性作用有关。收集个人呼吸区空气样本和尿液样本，分别确定多环芳烃的外部和内部暴露水平。收集精液以评估精子质量、DNA加合物和氧化损伤。该设计的特点包括对混杂因素的有效控制，准确的暴露确定，以及足够的功率来检测与暴露相关的精子质量变化。研究结果有助于为今后多环芳烃对生殖健康影响的相关研究奠定基础。此外，研究结果可用于改革最佳管理做法和政策，从而保护接触多环芳烃的个人和/或工人的生殖健康。因此，这项拟议的研究符合国家环境健康科学研究所和国家职业安全与健康研究所的使命，即通过了解多环芳烃与男性生殖健康的相互关系，减轻环境和职业原因造成的人类功能障碍的负担。

DESCRIPTION (provided by applicant): Exposure to Polycyclic Aromatic Hydrocarbons and Male Sperm Quality Polycyclic aromatic hydrocarbons (PAHs) are one of the most ubiquitous environmental pollutants. Humans are constantly exposed to complex mixtures from a variety of sources. Increasing evidence from animal studies has shown that PAHs, byproducts of the fuel combustion process, contribute to dysfunction of male rat sperms. At the same time, the effects of PAHs on human male sperms have been inconclusive based on the limited results from epidemiologic studies. We propose a longitudinal study to assess the effect of PAHs on male spermatozoa of human subjects. The central hypothesis is that PAH exposure contributes to decreased sperm quality of coke-oven workers. Our specific aims are to i) assess sperm quality of coke-oven workers; ii) determine the correlation between sperm chromatin integrity and PAH biomarkers; iii) determine sperm oxidative damage by identifying specific DNA lesions. The longitudinal study includes repeated measurements to account for PAH exposure as it relates to toxic effects on sperms during spermatogenesis. Personal breathing-zone air samples and urine samples will be collected to determine PAH external and internal exposure levels, respectively. Semen will be collected to assess sperm quality, DNA adducts, and oxidative damage. Features of this design include efficient control for confounding factors, accurate exposure ascertainment, and sufficient power to detect exposure related changes in sperm quality. Research results are useful to lay a foundation for future study related to the effects of PAHs on reproductive health. Also, the results can be useful for reforming best management practices and policies, thus protecting the reproductive health of individuals and/or workers exposed to PAHs. Thus, this proposed study is in line with the mission of the National Institute of Environmental Health Sciences and the National Institute for Occupational Safety and Health to reduce the burden of human dysfunction from environmental and occupational causes by understanding how PAHs interrelate with male reproductive health. PUBLIC HEALTH RELEVANCE: The longitudinal study aims to assess alteration of male sperm quality and DNA oxidative effects caused by occupational exposure to PAHs.