Registration Dossier

Administrative data

Endpoint:
short-term repeated dose toxicity: oral
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Only a brief report was available for review. The study predates guidelines and GLP.

Data source

Reference
Reference Type:
other company data
Title:
Unnamed
Year:
1967
Report Date:
1967

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
The study was carried out to see if there was any evidence for repeated administration of the test substance causing reduction in weight of testicles
GLP compliance:
no
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent

Test animals

Species:
rat
Strain:
Wistar
Sex:
male
Details on test animals and environmental conditions:
No details given in study report

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: oil
Analytical verification of doses or concentrations:
no
Duration of treatment / exposure:
twenty days
Frequency of treatment:
Daily, five days a week, for four weeks
Doses / concentrations
Remarks:
Doses / Concentrations:
100, 300, 1000 mg/kg bw
No. of animals per sex per dose:
Twenty
Control animals:
yes

Examinations

Observations and examinations performed and frequency:
Daily observations for condition, weekly bodyweight determination
Sacrifice and pathology:
Animals were sacrificed 24 hours after the final dose and the testicles were weighed and examined microscopically.

Results and discussion

Results of examinations

Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Organ weight findings including organ / body weight ratios:
no effects observed
Description (incidence and severity):
on testicle weight
Histopathological findings: non-neoplastic:
no effects observed
Description (incidence and severity):
on testicle histology

Effect levels

Dose descriptor:
NOAEL
Effect level:
> 1 000 mg/kg bw/day (nominal)
Sex:
male
Basis for effect level:
other: No change in bodyweight or effects on testicle weight or histology was observed.

Target system / organ toxicity

Critical effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
In a very limited non-guideline study conducted prior to the introduction of GLP, (trimethylsiloxy)phenylsilane was administered daily by oral gavage, five days a week for four weeks, at doses of 100, 300 and 1000 mg/kg bw/day. No mortalities occurred and no test substance-induced effects on condition or body weight gain were observed in the course of the study. On final sacrifice no effects on weight or histology of testicles were recorded and it is concluded by the reviewer that the NOAEL for effects on body weight and testicle weight and histology is > 1000 mg/kg bw/day.