以某化工企业的聚氯乙烯分厂为研究对象,引入美国环境保护署(EPA)推荐的健康风险评价四步法,即危害鉴定、剂量-反应评价、暴露评价和风险表征,对不同作业任务(清釜、看釜、巡检和配料)工人的氯乙烯职业暴露进行健康风险评价。结果表明,从非致癌效应来看,看釜、巡检和配料岗位工人暴露于VC引起肝细胞多态性的HI值均高于安全阈值1,其中看釜工的危害指数最大,引起的不利健康效应最严重。从致癌效应来看,清釜工暴露于VC引起肝血管肉瘤的风险处于可接受水平;而看釜工患肝血管肉瘤的风险值R,达到可接受上限10-4对应的工作年限ED=1.91 a,因此,需要尽可能地采用安全防护措施减少该岗位的职业暴露。巡检和配料岗位的肝血管肉瘤风险达到可接受水平上限10-4时,对应的工作年限分别为4.36 a和9.33 a。由于健康风险评价更侧重长期暴露危害物质对人体健康的影响,即使工作场所满足国标规定的浓度阈值,仍然存在工人长期暴露于低浓度致癌物的风险。 Taking a PVC plant of a chemical enterprise as a research object, the four-step health risk assessment recommended by the U.S. Environmental Protection Agency (EPA) was introduced, namely hazard identification, dose-response evaluation, exposure evaluation and risk characterization. (Clear kettle, see kettle, inspection and ingredients) workers VC exposure to health risk assessment. The results showed that in terms of non-carcinogenic effects, the HI values ​​of hepatocyte polymorphisms exposed to VC in workers exposed to VC, autopsy and ingredient workers were all above the safety threshold of 1, among which the hazard index was the largest The health effects are most serious. From the carcinogenic effect point of view, Qingke workers exposure to VC caused by the risk of hepatic angiosarcoma at an acceptable level; and see the kettle workers suffering from hepatic angiosarcoma risk value R, reaching an acceptable upper limit of 10-4 corresponding to the working life ED = 1.91 a. Therefore, it is necessary to adopt safety protection measures to minimize occupational exposure of the post. When the risk of hepatic angiosarcoma at the inspection and batching positions reaches an acceptable upper limit of 10-4, the corresponding working years are 4.36 a and 9.33 a, respectively. Since health risk assessment focuses more on the human health effects of long-term exposure to hazardous substances, there is a risk that workers will be exposed to low levels of carcinogens long-term even if the workplace meets the concentration threshold specified by the national standard.