目的探讨氯乙烯累积暴露造成的遗传毒性效应及其可能的影响因素,建立氯乙烯接触与遗传损伤效应间的剂量-反应关系,并估算氯乙烯致遗传毒性的基准剂量值。方法选择上海某氯碱化工厂氯乙烯作业工人为氯乙烯接触组(229人),对照组138人,使用调查问卷收集个人健康信息,采用胞质分裂阻滞微核评价外周血淋巴细胞DNA损伤;计算基准剂量(BMD),推算基准剂量的95%低限水平(BMDL)。结果对照组微核计数值为(1.23±0.11)‰,接触组微核计数值为(3.73±0.16)‰,两组比较,差异有统计学意义(P<0.01);氯乙烯累积接触量与微核率之间存在剂量-反应关系,得到BMD10的范围在7.20～9.64 mg/(m3.年),基准剂量下限值介于1.71～3.614mg/(m3.年)之间[2.86 mg/(m3.年)]。将工作年限按40年计,氯乙烯的时间加权平均阈限值应为0.072 mg/(m3.年)。结论氯乙烯作为确定的致癌物质,氯乙烯累积接触量与氯乙烯作业工人微核率之间存在相互关联;基于遗传毒性的职业接触限值的研究,有助于推动以保护职业有害物质接触人群为目标的职业安全制度的修订。 Objective To investigate the genotoxic effects caused by the cumulative exposure of vinyl chloride and its possible influencing factors, to establish a dose-response relationship between the exposure of vinyl chloride and the genetic damage effect and to estimate the baseline dose of vinyl chloride-induced genotoxicity. Methods A total of 229 VCV workers were employed in a chlor-alkali chemical factory in Shanghai. Among them, 138 were in the control group. Personal health information was collected using a questionnaire. DNA damage in peripheral blood lymphocytes was assessed using cytokinesis-block micronuclei. Baseline dose (BMD) was calculated and the 95% lower limit (BMDL) of the baseline dose was derived. Results The micronucleus count of the control group was (1.23 ± 0.11) ‰ and that of the contact group was (3.73 ± 0.16) ‰, the difference was statistically significant (P <0.01) There is a dose-response relationship between rates, giving a range of BMD10 of 7.20 to 9.64 mg / (m3. Year) and a baseline dose limit of 1.71 to 3.614 mg / (m3. Year) [2.86 mg / (m3 .year)]. Based on 40 years of service life, the time-weighted average threshold for vinyl chloride should be 0.072 mg / (m3. Year). Conclusions There is a correlation between the cumulative exposure of vinyl chloride and the micronucleus rate of vinyl chloride workers as a deterministic carcinogen. The study on the limit of occupational exposure based on genotoxicity may help to promote the protection of occupational exposure to harmful substances As the goal of the revision of the occupational safety system.