Long-term health care for workers exposed to low concentration of lead.

Practical indicators for the health care of 64 workers exposed to a low concen-tration of lead were looked for from an experience of the five-year health examina-tion carried out at six month intervals starting from the pre-employment in a modern industry producing ceramics. Blood lead levels in workers changed in relation to the amount of lead materials consumed for the production of ceramics. Furthermore, blood lead levels and delta-aminolevulinic dehydratase activity were different in each section of mixing, spray-drying, pressing, calcining, lapping, electroding and polarizing processes. Significant correlations between blood and urine lead concentrations were found when the blood lead level was higher than 20μg/100 ml of blood. Anemic markers of red blood cell count, hematocrit, hemo-globin levels and specific gravity of whole blood did not show a significant correla-tion to blood lead level, urinary lead level or ALAD activity. But, a positive or negative correlation was recognized between two items among blood lead level, urinary lead level, and ALAD activity.For these results, it is suggested that the most satisfactory examinations for diagnosis of the effect of low lead exposure are blood lead levels and ALAD activity in red blood cells. These parameters are useful for the preventing of lead poisoning.