Chan P C, Hasemani J K, Mahleri J, Aranyi C
National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
Toxicol Lett. 1998 Sep 30;99(1):23-32. doi: 10.1016/s0378-4274(98)00133-7.
Carcinogenesis studies of ethylbenzene were conducted because of its extensive use as a solvent and because it is structurally similar to the known carcinogen benzene. Groups of 50 male and 50 female Fischer rats and B6C3F1 mice were exposed to ethylbenzene by inhalation at 0, 75, 250, and 750 ppm 6 h per day, 5 days per week, for 2 years. The dose levels were selected based on the results of 13-week studies. In the 750 ppm group of male and female rats, body weights were slightly lower and incidences of renal hyperplasia and tubular neoplasms were significantly increased compared with controls. Incidence of testicular tumors was also significantly increased in male rats. Survival and body weights of the exposed groups of male and female mice and controls were comparable. Incidences of alveolar epithelium metaplasia, alveolar/bronchiolar adenoma, and hepatocyte hypertrophy and necrosis were significantly increased in the 750 ppm male mice and incidences of liver eosinophilic foci and hepatocellular neoplasms were significantly increased in the 750 ppm female mice compared with controls. Ethylbenzene is carcinogenic inducing neoplasms in kidneys and testes in Fischer rats and in lungs in male and liver in female B6C3F1 mice.
由于乙苯作为溶剂被广泛使用，且其结构与已知致癌物苯相似，因此开展了乙苯的致癌性研究。将50只雄性和50只雌性Fischer大鼠以及B6C3F1小鼠分为几组，每天吸入0、75、250和750 ppm的乙苯，每周5天，每天6小时，持续2年。剂量水平根据13周研究的结果选定。在750 ppm组的雄性和雌性大鼠中，与对照组相比，体重略有降低，肾增生和肾小管肿瘤的发生率显著增加。雄性大鼠睾丸肿瘤的发生率也显著增加。暴露组的雄性和雌性小鼠以及对照组的存活率和体重相当。与对照组相比，750 ppm雄性小鼠的肺泡上皮化生、肺泡/细支气管腺瘤以及肝细胞肥大和坏死的发生率显著增加，750 ppm雌性小鼠的肝脏嗜酸性病灶和肝细胞肿瘤的发生率显著增加。乙苯具有致癌性，可在Fischer大鼠的肾脏和睾丸以及雄性B6C3F1小鼠的肺部和雌性B6C3F1小鼠的肝脏中诱发肿瘤。
