INVESTIGATION OF HEMATURIA AT A PRINTING COMPANY

An investigation was undertaken at a printing company into an apparent ly high prevalence of trace dipstick hematuria discovered during routi ne medical examinations. In both the printing employees (n = 225) and a control group (n = 118) from other industries, the prevalence of hem aturia exceeded that described in most previous reports (31% and 25%, respectively, using the criterion of >12 glomerular red cells or >2 no nglomerular red cells/mul of urine). No focus of abnormality was ident ified within the printing plant and no association was identified betw een reported exposure to potentially toxic substances and the degree o f hematuria. An occupational hygiene inspection and medical follow-up of selected workers did not reveal any significant abnormalities. The limitations of available information concerning ''normal'' urinalysis results suggests that hematuria may not be a useful test for the scree ning of occupational groups at risk of bladder cancer.