Abstract:
We describe an approach for estimating the probability that study subjects were exposed to metalworking fluids (MWFs) in a population-based case-control study of bladder cancer. Study subject reports on the frequency of machining and use of specific MWFs (straight, soluble, and synthetic/semi-synthetic) were used to estimate exposure probability when available. Those reports also were used to develop estimates for job groups, which were then applied to jobs without MWF reports. Estimates using both cases and controls and controls only were developed. The prevalence of machining varied substantially across job groups (0.1->0.9%), with the greatest percentage of jobs that machined being reported by machinists and tool and die workers. Reports of straight and soluble MWF use were fairly consistent across job groups (generally 50-70%). Synthetic MWF use was lower (13-45%). There was little difference in reports by cases and controls vs. controls only. Approximately, 1% of the entire study population was assessed as definitely exposed to straight or soluble fluids in contrast to 0.2% definitely exposed to synthetic/semi-synthetics. A comparison between the reported use of the MWFs and U.S. production levels found high correlations (r generally >0.7). Overall, the method described here is likely to have provided a systematic and reliable ranking that better reflects the variability of exposure to three types of MWFs than approaches applied in the past. [Supplementary materials are available for this article. Go to the publisher\'s online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resources: a list of keywords in the occupational histories that were used to link study subjects to the metalworking fluids (MWFs) modules; recommendations from the literature on selection of MWFs based on type of machining operation, the metal being machined and decade; popular additives to MWFs; the number and proportion of controls who reported various MWF responses by job group; the number and proportion of controls assigned to the MWF types by job group and exposure category; and the distribution of cases and controls assigned various levels of probability by MWF type.].
摘要:
我们描述了一种在基于人群的膀胱癌病例对照研究中估计研究对象暴露于金属加工液(MWF)的概率的方法。关于特定MWF的加工频率和使用的研究主题报告(直,可溶性,和合成/半合成)用于估计暴露概率。这些报告还被用来为工作群体制定估计,然后应用于没有MWF报告的工作。仅使用病例和对照和对照进行了估计。加工的患病率在不同的工作群体中差异很大(0.1->0.9%),机械师、工具和模具工人报告的加工工作比例最高。有关直接和可溶MWF使用的报告在各个工作组之间相当一致(通常为50-70%)。合成MWF使用率较低(13-45%)。病例和对照报告与对照报告差异不大仅控制。大约,整个研究人群的1%被评估为明确暴露于直接或可溶性流体,而0.2%则明确暴露于合成/半合成材料。报告的MWF使用与美国生产水平之间的比较发现高度相关(r通常>0.7)。总的来说,本文描述的方法可能提供了系统和可靠的排名,与过去使用的方法相比,该排名更好地反映了暴露于三种类型MWF的变异性。【本文有补充材料。请访问出版商的在线版《职业与环境卫生杂志》,获取以下免费补充资源:职业历史中用于将研究主题与金属加工液(MWFs)模块链接的关键字列表;有关基于加工操作类型选择MWFs的文献建议,正在加工的金属和十年;MWF的流行添加剂;按工作组报告各种MWF响应的控件的数量和比例;按工作组和暴露类别分配给MWF类型的控件的数量和比例;以及按MWF类型分配不同概率级别的案例和控件的分布。].