Registration Dossier

Administrative data

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route
Dose descriptor:
NOAEL
10 mg/kg bw/day
Additional information

Toxicity to reproduction has been tested for sodium fluoride. No studies are available for disodium hexafluorosilicate. Due to the presence of hydrolysable groups on its chemical structure, fluorosilicate anions are not expected to remain in solution long under environmental conditions. Instead, fluoride anions will be formed. Thus, the performance of such tests is unjustified, since there are reliable studies on sodium fluoride or hydrogen fluoride. Read-across to sodium fluoride is appropriate.

Sodium fluoride in drinking water of Sprague-Dawley rats at levels up to 250 ppm (equivalent to 28.4 mg sodium fluoride/kg body weight/day or 12.8 mg fluoride/kg body weight/day) had no adverse effects on reproduction throughout three generations. No cumulative toxic effects were observed in the three generations.

Short description of key information:
No effects were observed.

Effects on developmental toxicity

Description of key information
No significant effects were oserved.
Effect on developmental toxicity: via oral route
Dose descriptor:
NOAEL
14 mg/kg bw/day
Additional information

A concentration of 175 ppm sodium fluoride in drinking water of a parental (P) and two filial generations (F1 and F2) of rats did not produce developmental effects and is considered a no-observed effect concentration for developmental toxicity. A concentration of 250 ppm sodium fluoride in drinking water of a parental (P) and two filial generations (F1 and F2) of rats caused statistically significant decreased ossification of the hyoid bone in F2 fetuses and is considered an effect concentration for developmental toxicity. No definative treatment-related effects on foetal growth or on the incidence of external, visceral, or skeletal abnormalities at levels of sodium fluoride up to and including 250 ppm (25.1 mg/kg/day) were found. Maternal exposure to sodium fluoride at conentrations up to 400 ppm (approximately 29 mg/kg/day) during organogenesis (gestation days 6 to 19) did not significantly affect the frequency of postimplantation loss, mean fetal body weight/litter, or external, visceral or skeletal malformations in the rabbit.

Justification for classification or non-classification

No classification is proposed, since data obtained from reliable studies show the absence of developmental toxicity or reproductive toxicity of fluoride.