Objective: To study the relationship between lymphocyte micronucleus rates and blood plasma levels of benzo(a)pyrene [B(a)P] in coking workers.
Methods: One hundred coking workers and 100 unexposed workers were selected, and their lymphocyte micronucleus rates and plasma levels, as well as workplace air concentrations, of B(a)P were determined.
Results: It showed that there was significant difference in plasma B(a)P level between coking workers and unexposed workers, and it correlated with air concentration of B(a)P in the workplace. Positive rates of micronucleus and rates of micronucleus lymphocyte were 60% and 1.79per thousand in coking workers and 29% and 1.10per thousand in controls, respectively, with very significantly statistical difference. It also showed that positive micronucleus rate correlated with plasma level of B(a)P in dose-effect pattern. Multivariate analysis showed that factors contributing to positive micronucleus rate ranked in such an order: plasma level of B(a)P, economic status, regularity of their lifestyle and smoking status of the coking workers.
Conclusion: Accumulation of B(a)P in blood plasma played a major role in the formation of lymphocyte micronucleus. Results of micronucleus test in coking workers could reflect preliminary damage to their health caused by it.