Cresols, monomethyl derivatives of phenol, are high production chemicals with potential for human exposure. The three isomeric forms of cresol are used individually or in mixtures as disinfectants, preservatives, and solvents or as intermediates in the production of antioxidants, fragrances, herbicides, insecticides, dyes, and explosives. Carcinogenesis studies were conducted in groups of 50 male F344/N rats and 50 female B6C3F1 mice exposed to a 60:40 mixture of m- and p-cresols (m-/p-cresol) in feed. Rats and mice were fed diets containing 0, 1500, 5000, or 15,000 ppm and 0, 1000, 3000, or 10,000 ppm, respectively. Survival of each exposed group was similar to that of their respective control group. Mean body weight gains were depressed in rats exposed to 15,000 ppm and in mice exposed to 3000 ppm and higher. A decrease of 25% over that of controls for the final mean body weight in mice exposed to 10,000 ppm appeared to be associated with lack of palatability of the feed. A marginally increased incidence of renal tubule adenoma was observed in the 15,000-ppm-exposed rats. The increased incidence was not statistically significant, but did exceed the range of historical controls. No increased incidence of hyperplasia of the renal tubules was observed; however, a significantly increased incidence of hyperplasia of the transitional epithelium associated with an increased incidence of nephropathy was observed at the high exposure concentration. The only significantly increased incidence of a neoplastic lesion related to cresol exposure observed in these studies was that of squamous cell papilloma in the forestomach of 10,000-ppm-exposed mice. A definitive association with irritation at the site-of-contact could not be made because of limited evidence of injury to the gastric mucosa at the time of necropsy. However, given the minimal chemical-related neoplastic response in these studies, it was concluded that there was no clear evidence of carcinogenicity in male rats or female mice exposed to the cresol mixture.

中文翻译：

---

甲酚对大鼠和小鼠的致癌作用研究。


甲酚是苯酚的单甲基衍生物，是一种高产量化学品，有可能被人类接触。甲酚的三种异构形式可单独或混合用作消毒剂、防腐剂和溶剂，或用作生产抗氧化剂、香料、除草剂、杀虫剂、染料和炸药的中间体。致癌研究是在 50 只雄性 F344/N 大鼠和 50 只雌性 B6C3F1 小鼠组中进行的，这些小鼠暴露于饲料中 60:40 的间甲酚和对甲酚混合物 (m-/p-cresol)。大鼠和小鼠的饮食分别含有 0、1500、5000 或 15,000 ppm 和 0、1000、3000 或 10,000 ppm。每个暴露组的存活率与其各自的对照组相似。暴露于 15,000 ppm 浓度的大鼠和暴露于 3000 ppm 及更高浓度的小鼠的平均体重增加受到抑制。暴露于 10,000 ppm 浓度的小鼠的最终平均体重比对照组下降了 25%，这似乎与饲料适口性的缺乏有关。在 15,000 ppm 暴露的大鼠中观察到肾小管腺瘤的发病率略有增加。发病率的增加没有统计学意义，但确实超出了历史对照的范围。未观察到肾小管增生发生率增加；然而，在高暴露浓度下，观察到移行上皮增生的发生率显着增加，并与肾病发生率增加相关。在这些研究中观察到，与甲酚暴露相关的肿瘤病变发生率唯一显着增加的是暴露于 10,000 ppm 甲酚的小鼠前胃中的鳞状细胞乳头状瘤。 由于尸检时胃粘膜损伤的证据有限，因此无法确定与接触部位刺激的明确关联。然而，鉴于这些研究中与化学相关的肿瘤反应极小，得出的结论是，没有明确的证据表明暴露于甲酚混合物的雄性大鼠或雌性小鼠具有致癌性。