Studies of pancreas, liver, and biliary cancer in a cohort of autoworkers exposed to metalworking fluids.

摘要

The General Motors/United Auto Workers (GM/UAW) cohort of 46,400 autoworkers is the largest study to date of workers exposed to metalworking fluids (MWFs). Subjects are comprised of all workers at three auto parts manufacturing plants in Michigan who worked for at least three years between 1941 and 1981. Although the majority of the cohort is comprised of white males, 17% of the workers are black and 10% are female. An extensive historical exposure assessment has been conducted. Cumulative aerosol MWF exposure in mg/m3-years to the different types of MWFs (straight, soluble, synthetic and semisynthetic), and operations (grinding and machining) has been estimated. Exposure to additives and contaminants (aluminum, biocide, ethanolamine, triethanolamine, iron, nitrosamines and steel) has also been quantified by duration of exposure in years.;At the end of the second follow-up period in 1994, a third of the cohort are deceased and elevated standardized mortality ratios (SMRs) for pancreatic and hepatobiliary cancer are found at all three plants and among both blacks, whites, and females. Previous investigations in the cohort have found excess risk for several digestive cancers (larynx, rectal, esophagus and stomach) associated with MWF exposure, therefore the elevated rates of pancreatic and hepatobiliary cancer are of concern.;This research will consist of four separate studies: A pilot case-control study of pancreatic cancers identified by death certificate through 1984 (the initial follow-up period); a cluster investigation of black pancreatic deaths occurring at Plant I; and two case-control studies of registry determined pancreas and hepatobiliary (liver and biliary) cancer based on an extension of follow-up through 1994. Conditional logistic regression models will be fit to estimate exposure response relationships;Both cancers are considered in the same proposal for two reasons: the organs share a close anatomic and physiologic relationship, and the occupational health literature suggests similar risks in related industries. The cancers share a particularly grim prognosis with an average median survival of three to six months after diagnosis. Treatment is infrequently curative and at best only modestly palliative. Prevention may be one of the few means to reduce mortality. Elucidation of risk factors is therefore of utmost importance.