ESTIMATION OF CUMULATIVE EXPOSURES TO NAPHTHA AT AN AUTOMOBILE FUEL-INJECTOR MANUFACTURING PLANT

As part of an epidemiologic study of neuropsychological and renal effe cts of occupational exposure to organic solvents, estimates of cumulat ive exposure to naphtha were derived for workers at an automobile fuel -injector manufacturing plant. The approach to exposure estimation was relatively unusual in three respects: (1) a marked association betwee n indoor naphtha air concentration and outdoor temperature was modeled and applied to detailed historical temperature data to calculate cumu lative exposure estimates; (2) the large number of investigator-genera ted air samples allowed the use of analyses of variance to compare alt ernative job-grouping schemes; and (3) the young age of the plant and few process changes allowed for historical exposure estimates with a h igh degree of confidence. The derived estimates of cumulative exposure appear to offer a firm basis for epidemiologic analyses of exposure-h ealth outcome relationships.