Neurologic and Reproductive Effects of Hexane on Workers

描述(申请人提供)：正己烷是汽车机械师从1990年到2002年使用的许多脱脂产品的一种成分；当几名机械师被发现患有周围神经病时，它的使用停止了。暴露数据表明，这些工人接触的正己烷水平低于阈值限值(TLV)的一半。动物研究表明，丙酮可以增强正己烷的影响并增加持久性，它于1997年被添加到这些产品中。这项回溯性队列研究旨在调查停止接触后，正己烷和丙酮可能对神经系统、生殖和眼睛造成的持续影响。样本将从1990-2002年期间受雇于旧金山湾区的机械师队列中抽取。潜在暴露的工人队列将通过工会记录(国际机械师和航空航天工人协会第190区)确定。将从工会记录中提取所有可能符合研究条件的参与者的数据。根据对哪些雇主使用含正己烷产品的了解，我们将从600名曾在曾经使用过含正己烷产品的汽车修理店工作的机械师中招聘，并从从未使用过含正己烷产品的汽车修理店再招聘600名。参与者将接受一份问卷调查，以获得所经历的症状和溶剂使用的历史，以及人口统计数据和潜在的混杂暴露。他们还将接受一系列测试，以评估周围神经功能和认知功能，以及蓝黄色辨别测试。将采集尿样以测定促性腺激素FSH和LH值。动物证据表明，正己烷可能导致睾丸萎缩，这将反映为尿液中FSH代谢产物水平的升高。调查问卷还将询问受试者可能遇到的任何生育问题。将根据溶剂的使用和使用历史，结合现有的暴露测量和历史产品成分信息，创建单独的正己烷和其他溶剂暴露情况。对数据的统计分析将调查接触史与症状学、临床和实验室检测结果以及怀孕时间的关系。这些结果可能为重新评估当前正己烷的TLV提供基础，特别是当它与丙酮一起使用时。与公众健康相关：己烷是一种在工业、消费品和汽油中广泛使用的化学品，已知有毒性影响，特别是对神经系统。由于正己烷暴露很普遍，了解当前允许的暴露水平是否具有保护性是很重要的。这项研究将通过调查一大群汽车修理工对神经系统、生殖系统和眼睛的可能影响来评估这一点，他们中的许多人在工作中接触过己烷。

DESCRIPTION (provided by applicant): N-hexane was a component of many degreasing products used by auto mechanics from 1990-2002; its use ceased when several mechanics were identified as having peripheral neuropathy. Exposure data suggested that these workers were exposed to levels of n-hexane less than half the Threshold Limit Value (TLV). Acetone, which has been shown in animal studies to potentiate the effects of n-hexane and increase persistence, was added to these products in 1997. This retrospective cohort study aims to investigate possible persistent neurologic, reproductive and ocular effects of n-hexane and acetone after cessation of exposure. The sample will be drawn from the cohort of mechanics employed in the Bay Area during 1990- 2002. The cohort of potentially exposed workers will be identified through union records (District 190 of the International Association of Machinists and Aerospace Workers). Data will be abstracted from the union records for all potentially eligible participants in the study. Based on knowledge of which employers used hexane-containing products, we will recruit a sample of 600 mechanics who had worked at automotive repair shops that had once used hexane-containing products and another 600 will be recruited from such shops that never used hexane-containing products. Participants will be administered a questionnaire to obtain histories of symptoms experienced and solvent use, as well as demographic data and potential confounder exposures. They will also be administered batteries of tests to assess peripheral nerve function and cognitive function, as well as a test of blue-yellow color discrimination. Urine samples will be collected for measurement of the gonadotropins FSH and LH. Animal evidence indicates that n-hexane may cause testicular atrophy, which would be reflected by raised urinary metabolite levels of the FSH. The questionnaire will also inquire about any fertility problems subjects may have experienced. Individual n- hexane and other solvent exposure profiles will be created on the basis of solvent use and employment histories combined with existing exposure measurements and historical product composition information. Statistical analysis of the data will investigate associations of exposure histories with symptomatology, clinical and laboratory test results, and time-to-pregnancy. These results may provide a basis for reassessment of the current TLV for n-hexane, particularly when it is used in conjunction with acetone. PUBLIC HEALTH RELEVANCE: Hexane is a very widely used chemical in industry, consumer products and gasoline that has known toxic effects, particularly on the nervous system. As hexane exposure is widespread, it is important to understand whether current permitted exposure levels are protective. This study will assess this by investigating possible effects on the nervous system, the reproductive system and the eye in a large group of auto mechanics, many of whom have been exposed to hexane in their work.