OCCUPATIONAL LEAD-EXPOSURE AND BLOOD-PRESSURE

Background. To assess the relation between occupational lead exposure and elevated blood pressure with consideration of a possible confoundi ng effect by noise exposure. Materials and Method. Some 112 male and 1 10 female workers at two lead battery manufacturing factories were rec ruited for this 1992 study in Taiwan. Study participants received regu lar physical examinations, including standard measurement of blood pre ssure, body height/weight. Current occupational exposures to lead and noise were measured by a personal sampling scheme and instruments, and included individual ambient lead/noise exposure and blood lead level. Results. Among the 222 battery-factory workers, the average blood lea d level was 56.9 +/- 25.5 mu g/dl (mean +/- standard deviation), the a verage concentration of ambient lead exposure was 0.190 +/- 0.331 mg/m (3), average noise exposure was 85.9 +/- 5.7 dBA, average systolic blo od pressure was 125.2 +/- 14.9 mmHg, average diastolic pressure was 80 .2 +/- 10.9 mmHg, and average mean arterial pressure was 95.2 +/- 11.1 mmHg. After considering all possible confounding variables, multivari ate regression analyses demonstrated that current blood lead level was not a significant predictor for both systolic and diastolic blood pre ssures in either sex. In the final model, body mass index and years of working in the factory were the only two factors significantly associ ated with a change in blood pressure. No evidence of an effect of ambi ent lead exposure or noise exposure on blood pressure were found. Conc lusions. The present study suggests that short-term lead exposure, eit her ambient lead exposure or blood lead level, was not related to bloo d pressure change among workers who had been exposed at work to occupa tional lead. These results add to the body of evidence indicating that blood lead exposure does not adversely affect blood pressure.