Thyroid sodium chlorate

Khan MA, Fenton SE, Swank AE, et al. A mixture of ammonium perchlorate and sodium chlorate enhances the pituitary-thyroid axis caused by the individual chemicals in adult male F344 rats. Toxicol Pathol 2005 33(7) 776-83. 

Another study described simple photometric determination of the iodine concentration in the thyroid tissue of small animals. Again, the method was based on the well-known catalytic Sandell-Kolthoff reaction. Prior to the analysis, the tissue was digested in a mixture of sodium chlorate and perchloric acid at 100 degrees C. Using this manner of digestion between 94 and 110% of iodine in the sample was recovered. Comparison with the neutron activation analysis showed excellent agreement of the obtained values (Tiran et al., 1991). 

Table 4. Key neoplastic and non-neoplastic thyroid lesions in the 2-year carcinogenicity study of sodium chlorate in F344/N rats ...

Sodium chlorate concentration in drinking-water (mg/l) Approximate dose of sodium chlorate (mg/kg bw per day) Survival Thyroid gland follicular cell hypertrophy incidence Follicular cell adenoma and carcinoma (combined) incidence... 

Table 5. BMDio and BMDLio calculations for thyroid gland follicular cell hypertrophy in male F344/N rats administered sodium chlorate in drinking-water for 2 years...

Female B6C3F1 mice (six per group) were administered sodium chlorate at concentrations of 0, 0.5,1.0,2.0, 4.0 and 6.0 g/l in the drinking-water for 105 days, equivalent to about 0, 50, 100, 200, 400 and 600 mg/kg bw per day expressed as chlorate. There were no effects on thyroid histology, but no other details were provided (Hooth et al., 2001). 

Based on the negative in vivo genotoxicity data and the nature of the histopathological observations, the Committee concluded that a non-genotoxic mode of action was likely for the induction of thyroid tumours by sodium chlorate. This mode of action is likely to be mediated via decreased serum thyroid hormones, leading to increased release of TSH and consequent stimulation of thyroid cell proliferation and thyroid gland growth, which can lead to thyroid tumours in rodents. 

Hooth, M.J., DeAngelo, A.B., George, M.H., Gaillard, E.T., Travlos, G.S., Boorman, G.A. Wolf, D.C. (2001) Subohronic sodium chlorate exposure in drinking water results in a ooncentration-dependent increase in rat thyroid follicular cell hyperplasia. Toxicol. Pathol. 29(2), 250-259,... 

CPL 46 EINECS 231-511-9 HSDB 5038 Irenat KM Sodium Perchlorate Natriumperchloraat Natriumper-chlorat Perchlorate de sodium Perchloric acid, sodium salt Sodio (perclorato di) Sodium (perchlorate de) Sodium perchlorate UN1502. Used in explosives has been used medicinally as a thyroid inhibitor. Crystals.dec about 130° d = 2.02. Kerr-McGee. 

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