Changes of Blood Lead and Oxidative Stress Enzymes among the Workers Exposed to Lead / 预防医学

ABSTRACT

Objective To study oxidative damage for occupational lead exposure, the relationship between serum lead and oxidative stress enzymes, and the mechanism of lead poisoning. Methods The lead content in the air was determined by flame atomic absorption spectrophotometric method, the lead concentration in serum was determined by graphite furnace atomic absorption spectrophotometric method. Superoxide dismutase (SOD) and malondialdehyde (MDA) as the effect indicators of oxidative stress were used to analyze the relationship between blood lead and the indicators. Results Five workplaces were monitored. The lead concentration in exposed group (244.27±124.59ug/L) was significantly higher than that in control group (P<0.01). The SOD activity in exposure group was 61.27±6.97KU/L not significantly different from that in control group (P>0.05), while MDA concetration in exposure group (9.42±3.89mmol/L) was significantly higher than in control group (P< 0.01). There was positive correlation between serum MDA and blood lead concentration (r = 0.3, P < 0.01) . The effects of smoking and drinking on the SOD activity and MDA content were not statistically significant. Conclusion Occupational lead exposure increases the blood lead level. It is inconsistent between the changes of lead concentration in workplace air and in blood lead. Blood lead is a sensitive indicator as the lead internal exposure. The higher blood lead level is, the higher the SOD activity and the MDA concentration, the more seriousthe oxidative damage is.