工业中的致癌因素往往难以发现和肯定,一般认为要符合下列条件,才能确认致癌物与接触工人罹患肿瘤之间的因果关系:①接触人群的肿瘤发病率高于不接触人群;②接触致癌物的剂量与发生致癌效应之间有正比关系;③发病部位可能是接触部位,或者是经过代谢以后能够转运到达的部位;④在实验动物中,该致癌物质能够引起相同的致肿瘤作用。近年来国外有不少关于氯甲甲醚和二氯甲醚的毒性报导,并证明它们是具备了以上几方面的条件,且认为是对人有较强致 Carcinogenic factors in industry are often difficult to find and affirmative, generally agreed that in order to meet the following conditions, in order to confirm the causal relationship between carcinogens and workers exposed to cancer: ① the incidence of cancer exposure to the population is higher than non-contact with the population; ② exposure to carcinogens Of the dose and the occurrence of carcinogenic effects have a direct relationship between; ③ the site of disease may be contact parts, or after the transfer of metabolites to reach the site; ④ In experimental animals, the carcinogen can cause the same tumor-causing effect. In recent years, there are many foreign reports on the toxicity of chloromethyl ether and dichloro methyl ether, and prove that they are equipped with the above conditions, and that is stronger for people