A 13‐Week Toxicity Study of Bismuth in Rats by Intratracheal Intermittent Administration

A 13‐Week Toxicity Study of Bismuth in Rats by Intratracheal Intermittent Administration: Yuri Sano, et al. Department of Preventative Medicine and Public Health, School of Medicine, Keio University—Although bismuth is widely used as a lead substitute in the industrial field, the toxicity of bismuth by inhalation is little known. We performed a 13‐wk intratracheal intermittent bismuth dose toxicity study. Bismuth was administered at dose levels of 0, 0.8, 4, 20 mg/kg to male Crj:CD(SD)IGS rats (SPF) by intratracheal intermittent administration once a week for thirteen weeks to investigate its potential toxic effects; especially for specific adverse effects and changes related to pre‐neoplastic lesions. Our results showed foreign body inflammation in the lungs, which was caused by intratracheal administration of bismuth, and physical changes related to pulmonary lesions; however, there were no serious changes in other organs. We concluded that dose‐dependent, but not specific adverse effects, were attributable to bismuth inhalation in the rat.