Changes in external and internal lead load in different working areas of a starter battery production plant in the period 1982 to 1991.

Our investigation was based on routine ambient and biological monitoring data in a starter battery production plant from 1982 to 1991. This retrospective longitudinal study included 134 blue collar workers in seven main production areas (casting, lead oxide production, bunker, pasting, formation, plate stacking, assembly). Over the whole period a statistically significant decrease in blood lead concentration in the whole sample, from 48.92 micrograms/dl (1982) to 22.99 micrograms/dl (1991), could be ascertained. This positive trend could also be proven for the most important production areas. The highest internal lead load was present in employees from the formation and adjoining production areas, followed by pasting, casting and assembly. In comparison to other battery factories our results are in the lower range. Furthermore, we carried out a data linkage between air and blood lead concentrations. We were able to demonstrate a decrease in external lead load in most of the production areas, but this reduction was not so distinct as that in the blood lead concentration. These results indicate the efficiency of preventive efforts in technical work protection and especially in intensive medical supervision of the exposed workers. Influencing personal hygienic behaviour and intervention at blood lead levels of 50 micrograms/dl promises the best success in worker protection.