Silanediol, 1-methyl-1-(1-methylethoxy)-, 1,1-diacetate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route

Dose descriptor:

NOAEL

225 mg/kg bw/day

Additional information

In a Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test according to OECD guideline 422 (Tyl, 2002) male and female rats were treated with 25, 75 and 225 mg/kg bw/day Methyldiacetoxyisopropoxysilane. Female rats were treated daily for 10 weeks, male rats daily for 6 weeks. Furthermore the F1 generation was treated from weaning (pnd 21), for approximately seven more weeks (dosing for F1 selected pups began on pnd 22 and continued until all pups were at least 70 days of age). Only mild systemic toxicity in F0 parental males at 225 mg/kg/day was observed, expressed as sporadic effects on hematologic and neurobehavioral parameters and histopathologic lesions in the stomachs of F0 (but not Fl) males. There were no treatment- or dose-related effects on absolute organ weights or organ weights relative to terminal body or brain weights, or on gross findings, clinical chemistry, or urinalysis. There was no evidence of F0 reproductive toxicity in either sex at any dose. However, there were no effects on Fl male reproductive system histopathology or andrology at any dose. There was no other evidence of Fl offspring toxicity, either pre- or postnatally. There were no effects of treatment on acquisition of puberty in either sex and no changes in Fl adult male reproductive tract histopathology or andrology. In conclusion, administration of Methyldiacetoxyisopropoxysilane by gavage once daily at 0, 25, 75, or 225 mg/kg bw/day to parental F0 rats, ten/sex/group, through prebreed, mating, gestation, and lactation, and direct dosing to F1 offspring from weaning to scheduled sacrifice on or about pnd 70, resulted only in minimal adult F0 parental toxicity at 225 mg/kg/day. Therefore, under the conditions of this study, the no observable adverse effect level (NOAEL) for systemic parental toxicity is 75 mg/kg/day; for reproductive and offspring toxicity, the NOAEL is >=225 mg/kg/day.

Short description of key information:
Combined Repeated Dose Toxicity Study with the Reproduclive/Developmental Toxicity Screening Test via oral gavage to rats (OECD 422): NOAEL for reproductive and offspring toxicity: >= 225 mg/kg bw/day

Justification for classification or non-classification

In a Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test the no observable adverse effect level (NOAEL) for systemic parental toxicity was 75 mg/kg/day; for reproductive and offspring toxicity, the NOAEL was >=225 mg/kg/day. Therefore Methyldiacetoxyisopropoxysilane has not to be classified for reproduction toxicity according to DSD and CLP.