Urinary concentrations of trichloroacetic acid in Danish workers exposed to trichloroethylene, 1947-1985

Background Since 1947 the National Labour Inspection Service in Denmark has relied upon urinary measurements of trichloroacetic acid (TCA) in surveys of the occupational exposure to trichloroethylene (TCE). Methods We examined the paper files relating to 2397 TCA measurements to ex tract information about the year the company, the work process and the work er We used multiple regression models to analyze the effects of various fac tors on the urinary concentration of TCA. Results The regression analyses showed that (I) a four-fold decrease in TCA concentrations occurred from 1947 to 1985; (2) the highest concentrations were observed in the iron and metal, chemical, and dry cleaning industries; (3) TCA levels were two times higher among men compared with women in the iron and metal and dry cleaning industries; (4) TCA concentrations were hig her among younger compared with older workers; and (5) persons working in a n area in which TCE was used, but not working with TCE themselves, also sho wed urinary TCA levels indicative of exposure. Conclusion Calendar year; type of industry, degree of contact with TCE, sex and age were predictors of TCA concentration in the urine of Danish worker s. (C) 2001 Wiley-Liss, Inc.