Abstract

In order to evaluate possible effects of lead exposure, lead absorption and subjective symptoms in the expressway tollgate workers, 147 workers who have benn working at 4 expressway tollgates werer studied. Study variables were blood lead(PbB), urine lead(PbU), delta-aminolevulinic acid in urine (ALAU), coproporphyrin in urine (CPU), zinc protoporphyrin in whole blood (ZPP), hemoglobin, hematocrit, red blood cell count and symtom index of lead exposure. Subjective symptoms, 16 items, were investigated by a physician's interview. The results were as follows: 1. The most prevailing subjective symptom related to lead exposure were reported fatigue (41.5%), follow by abdominal discomfort (26.5%), loss of appetite (23.8%) and numbness (21.0%). 2. The mean air concentrations of lead at inside and outside of tollbooth were 6.8 (0.2~17.9) and 4.8 (0.2~17.5) microgram/m3, respectively. 3. The mean values of lead absorption indices (blood lead, urine lead, delta-aminolevulinic acid, coproporphyrin in urine and zinc protoporphyrin in blood) of workers were 19.99 (4.2~38.9) microgram/ dl, 29.82(6.3~68.6) microgram/l, 1.04(0.17~3.41) mg/l, 30.30(11.6~58.0) microgram/l and 10.51(1.0~31.0) microgram/l, respectively. And the mean values of hemoglobin, hematocrit and red blood cell count were 15.41 (10.2~18.9)g/dl, 45.88(33.9~54.7)%, 497.37(415~591)x10(4)/mm3, respectively. 4. The mean number of positive responses to subjective symptoms(16 items) was 2.08(13%) and tended to decrease with increasing work duration and age. 5. The number of positive responses of subjective symptoms did not show dose-response relationship with lead absorption indices.

• Keywords: lead exposure;subjective symptoms;lead absorption indices;tollgate workers