Occupational exposure to inorganic lead in a printing plant in Mexico City.

Objective. To describe occupational lead exposure and its biological indica tors in workers in a printing company. Material and methods. An epidemiolog ical and industrial hygiene research was undertaken. Lead was measured in t he air of work environment and on the hands of the participants; additional ly, subjects underwent a venous blood samples for the determination of whol e blood lead by atomic absorption spectrophotometry; and a bone lead measur ement using a spot-source Cd K-X-ray fluorescence instrument. Also, a stand ardized questionnaire was applied. We obtained information on demographic a nd life styles factors,work history, type of work, position and activity wi thin the company. Results. Of the 209 workers, 117 agreed to participate an d 90 (83.3% males and 16.7% females) completed all phases of the study. The average lead concentrations were: in air samples, of 0.94 mu g/m(3); in ha nds before washing, of 6 802 mu g/m(2); in hands after washing, of 194 mu g /m(2); in whole blood, of 12.3 mu g/dl; and in tibia and fibula, of 25.9 an d 43.3 mu g Pb/g of bone mineral, respectively. Important variations in the se measurements were observed according to the workers post. Conclusions. W orldwide, lead exposure levels have been used to evaluate acute exposures b eing in the workplace. The higher lead levels find in the bone of the worke rs in this study are similar to other occupational studies in the United St ates of America and suggest that the accumulated metal in bone may be an im portant endogenous exposure source, and here its measurement importance. Ho wever in developing countries because its high costs per application, the m easurements in bone lead become limited to epidemiological research, althou gh not as an instrument for occupational epidemiological surveillance. In M exico, there are no reliable studies of occupational lead exposure, which w ould allow the establishment of both, maximum permissible ambient and biolo gical levels. This study is intended to contribute to blood lead standard s etting, which is being discussed in Mexico.