Shukla Y, Baqar S M, Mehrotra N K
Laboratory of Environmental Carcinogenesis, Industrial Toxicology Research Centre, Lucknow, India.
Food Chem Toxicol. 1996 Mar;34(3):283-9. doi: 10.1016/0278-6915(95)00113-1.
Thiram (tetramethyl thiuram disulfide), a carbamate fungicide, is used in the rubber processing industry as an accelerator and vulcanizing agent. Previous studies evaluated the tumorigenic potential of thiram in rodents, but failed to provide conclusive results. In the present study the tumorigenic potential of thiram was evaluated in Swiss albino mice by a two-stage initiation-promotion protocol and a long-term in vivo bioassay for carcinogenicity. Results revealed that following tumour initiation with thiram and promotion with 12-O-tetradecanoyl phorbol 13-acetate, skin tumours developed, mostly at the site of treatment (dorsal skin) in single and multiple dose-initiated animals. Similarly, papillomatous growths were observed on the dorsal skin of the mice initiated with a single subcarcinogenic dose of dimethylbenzanthracene and promoted with thiram. Thiram failed to provoke tumorigenesis when tested as a complete carcinogen for up to 52 wk and thereafter the study was terminated due to increased mortality. It is concluded that thiram has both tumour initiating and tumour-promoting potential in both sexes of Swiss albino mice following topical exposure at the tested dose level.
福美双（四甲基秋兰姆二硫化物）是一种氨基甲酸酯类杀菌剂，在橡胶加工业中用作促进剂和硫化剂。先前的研究评估了福美双在啮齿动物中的致癌潜力，但未能得出确凿结果。在本研究中，通过两阶段启动-促进方案和长期体内致癌生物测定，评估了福美双在瑞士白化小鼠中的致癌潜力。结果显示，在用福美双启动并以12-O-十四烷酰佛波醇13-乙酸酯促进后，皮肤肿瘤出现，大多出现在单次和多次剂量启动动物的治疗部位（背部皮肤）。同样，在用单次亚致癌剂量的二甲基苯并蒽启动并用福美双促进的小鼠背部皮肤上观察到乳头状瘤生长。当作为完全致癌物进行长达52周的测试时，福美双未能引发肿瘤发生，此后由于死亡率增加，该研究终止。得出的结论是，在测试剂量水平下局部暴露后，福美双在瑞士白化小鼠的两性中均具有肿瘤启动和肿瘤促进潜力。
