Lead exposure and blood lead level of workers in a battery manufacturing plant in Thailand.

This study was conducted in a battery manufacturing plant where lead was used in the processes of production, to survey the working conditions and safety behaviors, and to measure the airborne lead level contaminated in the workplace and the blood lead level of workers. The survey of working conditions showed that the workers were directly exposed to lead in sections e.g. grid casting, spreading, forming and polishing, assembly and special battery production sections. Some workers in these sections used a cotton mask to protect dust exposure, but most workers did not use any masks. High airborne lead level more than 0.2 mg/m3 was frequently measured in these sections. Geometric average of blood lead level slightly increased from 17.9 microg/dl to 22.3 microg/dl during 1998 and 2001. However, the geometric average of blood lead level dropped to 17.4 microg/dl in 2002. No workers had blood lead level above 60 microg/dl. Workers with different age groups had no significantly different average blood lead level. Workers whose duration of work was between 20-29 years had average blood lead level of 21.5 microg/dl. This group of workers had slightly higher blood lead level than those whose duration of work was 19 years or less, but with no significant difference. 21 subjects underwent annual health examination and exposure monitoring in 2002. There was no significant relation between airborne lead level and blood lead level.