title: Thyroid follicular lesions induced by thiazole-Zn feed treatment for one year in Sprague-Dawley rats.
abstract: Thiazole-Zn is a newly created Chinese systemic fungicide that is a thiadiazole compound. The toxicity of thiazole-Zn was examined in Sprague-Dawley rats fed diets containing 0, 4, 20 and 100mg/kg thiazole-Zn for one year. Lower body weight gains were noted in both males and females of the 100mg/kg diet group. Moreover, we show that the toxicity of thiazole-Zn was low, as evidenced by the absence of toxicologically significant changes in the general condition and appearance, hematology and clinical chemistry parameters, organ weights and necropsy findings of the rats. Thyroid follicular cell hyperplasia was the only finding of potential significance. The incidence of thyroid follicular cell hyperplasia significantly increased in high-dose males (4/10) and females (3/10) at the 26-week interim examination; one follicular adenoma in the thyroid was observed in high-dose males. At 52 weeks, the incidence of thyroid follicular cell hyperplasia was significantly higher in high-dose males (4/10) and females (4/10) than in the controls. Two thyroid follicular adenomas were observed in high-dose males. Other treatment-related effects and tumors at other sites were not observed. This study suggests that thiazole-Zn is a thyroid disrupter and likely a rat thyroid carcinogen.
authors: Tianjin Institute of Health and Environmental Medicine, A Key Laboratory of Risk Assessment and Control Technology for Environment & Food Safety, Tianjin 300050, China.
authors: Honglian
authors: H
authors: Yang
authors: Pharmaron Preclinical Services Laboratories, Beijing 102206, China.
authors: Qingxi
authors: Q
authors: Kong
authors: Tianjin Institute of Health and Environmental Medicine, A Key Laboratory of Risk Assessment and Control Technology for Environment & Food Safety, Tianjin 300050, China.
authors: Huanliang
authors: H
authors: Liu
authors: Tianjin Institute of Health and Environmental Medicine, A Key Laboratory of Risk Assessment and Control Technology for Environment & Food Safety, Tianjin 300050, China.
authors: Wei
authors: W
authors: Zhang
authors: Tianjin Institute of Health and Environmental Medicine, A Key Laboratory of Risk Assessment and Control Technology for Environment & Food Safety, Tianjin 300050, China.
authors: Lei
authors: L
authors: Tian
authors: Tianjin Institute of Health and Environmental Medicine, A Key Laboratory of Risk Assessment and Control Technology for Environment & Food Safety, Tianjin 300050, China.
authors: Bencheng
authors: B
authors: Lin
authors: Tianjin Institute of Health and Environmental Medicine, A Key Laboratory of Risk Assessment and Control Technology for Environment & Food Safety, Tianjin 300050, China.
authors: Yanjun
authors: Y
authors: Fang
authors: Tianjin Institute of Health and Environmental Medicine, A Key Laboratory of Risk Assessment and Control Technology for Environment & Food Safety, Tianjin 300050, China. Electronic address: zhugexi2003@sina.com.
authors: Zhuge
authors: Z
authors: Xi
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000008:administration & dosage / Q000009:adverse effects*; D056831:Coordination Complexes / Q000008:administration & dosage / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006965:Hyperplasia / Q000139:chemically induced; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013830:Thiadiazoles / Q000008:administration & dosage / Q000009:adverse effects*; D013961:Thyroid Gland / Q000187:drug effects* / Q000473:pathology
chemical_list: D000935:Antifungal Agents; D056831:Coordination Complexes; D013830:Thiadiazoles; C000606707:bis(2-amino-5-sulfhydryl-1,3,4-thiadiazole)zinc(II)
keywords: Chronic toxicity; Thiazole–Zn; Thyroid follicular cell hyperplasia; Thyroid tumor in rats