Hake C L, Stewart R D
Environ Health Perspect. 1977 Dec;21:231-8. doi: 10.1289/ehp.7721231.
There is considerable potential for worker exposure to tetrachloroethylene, both by skin contact and by inhalation, during its use in dry cleaning and degreasing operations. This paper reviews accounts of both accidental overexposures of workers and controlled exposures of human subjects by these two routes of exposure. Several reported cases of accidental overexposure to anesthetic doses of the chemical reveal that recovery was generally complete but prolonged, and accompanied by many days of measurable levels of the chemical in the patient's alveolar breath. Chronic overexposures of workmen have lessened since the general acceptance by the Western world of the recommended TLV of 100 ppm for 8 hr of daily exposure. Controlled inhalation studies with volunteer subjects at this level of exposure revealed no effects upon health but did indicate a slight decrement in performance on a coordination test. Additional behavioral and neurological tests revealed no interactive effects when alcohol or diazepam, two depressant drugs, were added singly to tetrachloroethylene exposures. Individual susceptibility to the vapor of this chemical, as evidenced by subjective complaints, was noted in approximately one of ten subjects. The authors conclude that the TLV concentration of 100 ppm in the workplace has a negligible margin of safety regarding unimpaired performance during repeated exposures which could be especially hazardous if the worker is physically active or is in a situation where skin absorption presents an added burden.
在干洗和脱脂作业中使用四氯乙烯时，工人通过皮肤接触和吸入接触该物质的可能性很大。本文回顾了工人意外过度接触以及人体受试者通过这两种接触途径进行受控接触的相关报道。几起报告的意外过量接触该化学物质麻醉剂量的案例显示，恢复通常是完全的，但过程漫长，且患者肺泡呼出气体中该化学物质的可测量水平会持续多日。自从西方世界普遍接受每日8小时接触的建议阈限值为100 ppm以来，工人的慢性过度接触情况有所减少。在这个接触水平对志愿者进行的受控吸入研究表明，对健康没有影响，但确实显示在一项协调测试中的表现略有下降。当将两种抑制性药物酒精或地西泮单独添加到四氯乙烯接触中时，额外的行为和神经学测试显示没有交互作用。大约十分之一的受试者出现主观不适，表明个体对这种化学物质的蒸气敏感。作者得出结论，就重复接触期间不影响表现而言，工作场所100 ppm的阈限值浓度的安全边际可忽略不计，如果工人身体活跃或处于皮肤吸收增加负担的情况下，这可能特别危险。
