Effect of Cumulative Blood Lead and Cumulative Blood ZPP as Lead Body Burden on Renal Lead Biomarkers / 대한산업의학회지

OBJECTIVE: To evaluate the possibility of cumulative blood lead and blood ZPP as surrogates of lead body burden and to investigate their association with renal function as an index of lead body burden. METHODS: The study subjects comprised 678 lead workers with past blood lead and blood ZPP data from their employment. Cumulative blood and ZPP were calculated by accumulating the every year mean value of both indices from the new employment since 1983. To assess the cumulative data of lead workers who started their lead work before 1983, the years before 1983 were simulated with the first available data from 1983. Study variables for lead body burden were tibia bone lead and DMSA chelatable lead, whereas those for current lead biomarkers were blood lead and blood ZPP. BUN and serum creatinine were selected as clinical renal biomarkers, while NAG (N-acetyl-D-glucosamine) and RBP (Retinol binding protein) were selected as early renal biomarkers. RESULTS: The association between cumulative blood lead and blood ZPP with tibia bone lead was statistically significant with determinant coefficients (r(2)) of 0.72 and 0.567, respectively, and their relationships were better explained by the curvilinear regression model. In multiple regression analysis of current lead biomarkers on the renal biomarkers after controlling for possible confounders (age, sex, job duration, smoking and drinking status), blood lead was associated only with log-transformed NAG, whereas blood ZPP was associated with 3 other renal biomarkers. On the other hand, in multiple regression analysis of biomarkers of lead body burden on renal biomarkers after controlling for possible confounders (age, sex, job duration, smoking and drinking status), cumulative blood ZPP and tibia bone lead were associated with all 4 renal function biomarkers, whereas cumulative blood lead and DMSA chelatable lead were associated with 3 renal biomarkers except BUN. CONCLUSION: Cumulative blood and ZPP were demonstrated to be good surrogates of lead burden. Furthermore, the cumulative blood ZPP was confirmed to have a better association than the cumulative blood lead.

A cohort study on blood zinc protoporphyrin concentration of workers in storage battery factory / 예방의학회지

To investigate the effectiveness of the interventions in working environment and personal hygiene for the occupational exposure to the lead, the blood zinc protoporphyrin(ZPP) concentrations of 131 workers ( 100 exposed subjects and 31 controls ) of a newly established battery factory were analyzed. They were measured in every 3 months up to 18 months. Air lead concentration (Pb-A) of the workplaces was also checked for 3 times in 6 months interval from August 1987. Environmental intervention included the local exhaust ventilation and vacuum cleaning of the floor. Intervention of the personal hygiene included the daily change of clothes, compulsory shower after work and hand washing before meal, prohibition of cigarette smoking and food consumption at the work site and wearing mask. Mean blood ZPP concentration of the controls was 16.45+/-4.83 microgram/dashliter at the preemployment examination and slightly increased to 17.77+/-5.59 microgram/dashliter after 6 months. Mean blood ZPP concentration of the exposed subjects who were employed before the factory was in operation (Group A) was 17.36+/-5.20 microgram/dashliter on employment and it was increased to 23.00+/-13.06 microgram/dashliter after 3 months. The blood ZPP concentration was increased to 27.25+/-6.40 microgram/dashliter on 6 months (p<0.01) after the employment which was 1 month after the initiation of intervention program. It did not increase thereafter and ranged between 25.48 microgram/dashliter and 26.61 microgram/dashliter in the subsequent 4 results. Mean blood ZPP concentration of the exposed subjects who were employed after the factory had been in operation but before the intervention program was initiated (Group B) was 14.34+/-6.10 microgram/dashliter on employment and it was increased to 28.97+/-7.14 microgram/dashliter (p<0.01) in 3 months later(1 month after the intervention). The values of subsequent 4 tests were maintained between 26.96 microgram/dashliter and 27.96 microgram/dashliter. Mean blood ZPP concentration of the exposed subjects who were employed after intervention program had been started (Group C) was 21.34+/-5.25 microgram/dashliter on employment and it was gradually increased to 23.37+/-3.86 microgram/dashliter (p<0.01) after 3 months, 23.93+/-3.64 microgram/dashliter after 6 months, 25.50+/-3.01 microgram/dashliter (p<0.01) after 9 months, and 25.50+/-3.10 microgram/dashliter after 12 months. Workplaces were classified into 4 parts according to Pb-A. The Pb-A of part I, the highest areas, were 0.365 microgram/m4, and after the intervention the levels were decreased to 0.216 microgram/m4 and 0.208 microgram/m4 in follow-up test. The Pb-A of part II which was resulted in lower value than part I was decreased from 0.232 microgram/m4 to 0.148 microgram/m4, and 0.120 microgram/m4 after the intervention. The Pb-A of part III was tested after the intervention and resulted in 0.124 microgram/m4 in January 1988 and 0.081 microgram/m4 in August 1988. The Pb-A of part IV was also tested after the intervention and resulted in 0.110 microgram/m4 in August 1988. There was no consistent relationship between Pb-A and blood ZPP concentration. The blood ZPP concentration of the group A and B workers in the part of the highest Pb-A were lower than those of the workers in the parts of lower Pb-A. The blood ZPP concentration of the workers in the part of the lowest Pb-A increased more rapidly. The blood ZPP concentration of the group C workers was the highest in part III. These findings suggest that the intervention in personal hygiene is more effective than environmental intervention, and it should be carried out from the first day of employment and to both the exposed subjects, blue color workers and the controls, white color workers.

The effect of smoking and drinking habit on the health status of lead workers / 예방의학회지

To investigate the effect of smoking and drinking habit on the health status in lead using industries, 2,785 male workers in lead using industries (7 storage battery industries, 7 secondary smelting and related industries, and 4 primary metal and other manufacturing industries) were selected for this study. This study was carried out as a part of periodic health examination. Selected study variables were zinc protoporphyrin in whole blood (ZPP), SGOT and SGPT for laboratory test. Questionnaire for lead related symptoms and smoking and drinking habit was provided to all the workers and filled up by themselves and reconfirmed by physician. The results obtained were as follows; 1. The overall smoking and drinking rate of study population were 69.8% and 73.6%, respectively. While the smoking and drinking rate of storage battery workers were 68.8% and 72.3%, those of secondary smelting industries and other industries were 66.0% and 66.4% and 74.6 and 80.3% respectively. 2. While the mean values of blood ZPP of lead exposed workers were significantly higher than other group, those of SGOT of storage battery workers were significant higher than other worker. But there were no differences of mean values of other variables. 3. Smoking habit did not affect on the mean value of blood ZPP of workers in special health examination group, but there were significant differences of blood ZPP and SGOT between drinker and non-drinker. 4. Symptom prevalence of lead exposure were higher in drinking and smoking group than non-drinking and non-smoking group. 5. In multiple regression analysis of the total lead related symptoms, blood ZPP, SGOT, and SGPT as dependent variable, respectively, and age, work duration, blood ZPP, pack year and amount of alcohol drinking as independent variables, work duration, pack year, amount of alcohol drinking, age contributed to total symptoms; and age, work duration, pack year contributed to blood ZPP; and age, amount of alcohol drinking, work duration contributed to SGOT; and pack year contributed to SGPT.