Registration Dossier

Administrative data

Description of key information

In a 90-day repeated oral gavage study conducted to OECD 408 and to GLP (Dow Corning Corporation, 1995), no changes attributable to treatment at doses up to 1000 mg/kg/day (the highest dose tested) silsesquioxanes, phenyl, were observed in rats.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Study duration:
subchronic
Species:
rat

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

The key study is the only repeated dose study available for Silsesquioxanes, Phenyl (Dow Corning Corporation, 1995). In this study F344 rats were given the test substance by oral gavage at doses of 25, 150, 450 or 1000 mg/kg/day (controls received corn oil only) for 91 or92 consecutive days. Absolute and relative liver weights showed statistically significant increase in all treated groups; however, no underlying histopathology was observed to support the organ weight change. Therefore the NOAEL for this study was 1000 mg/kg bw/day.


Justification for classification or non-classification

Based on the 90-day oral gavage study Silsesquioxanes, Phenyl does not require classification for adverse effects following repeated exposures according to Regulation (EC) No 1272/2008.