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Toxicological information

Genetic toxicity: in vivo

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Administrative data

Endpoint:
in vivo mammalian germ cell study: cytogenicity / chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1974
Report Date:
1974

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 478 (Genetic Toxicology: Rodent Dominant Lethal Test)
GLP compliance:
no
Type of assay:
rodent dominant lethal assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: no data
- Age at study initiation: 10 - 12 weeks

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
- vehicle: 0.85 % saline
- Volume of the vehicle: no data
- Justification for choice of solvent/vehicle: no data
- Concentration of test material in vehicle: no data


MAXIMUM DOSE VOLUME APPLIED: no data
Duration of treatment / exposure:
single administration ("acute") and repeated administration (5 times, "subacute")
Frequency of treatment:
1x and 5x (1x/day)
Doses / concentrations
Remarks:
Doses / Concentrations:
150, 500 and 1500 mg/kg bw, suspended in 0.85 % saline, administered 1x/d (Test I), 5000 mg/kg bw (Test II)
Basis:

No. of animals per sex per dose:
10 males (treated) mated to virgin female rats (2 females/1 male)
Control animals:
yes, concurrent vehicle
yes, historical
Positive control(s):
triethylene melamine
- Route of administration: i.p.
- Doses / concentrations: 0.3 mg/kg bw

Examinations

Tissues and cell types examined:
Fertility index = No. pregnant females / No. mated
Total No. of implantations
Total number of corpora lutea
Preimplantation losses
see Report p. 132 - 135:
Dead implants
Females with one or more dead implants
Dead implants per total implants
Statistics:
Chi-square test, Armitage´s trend test, regression analyses, Freeman-Tukey transformation, t-test (Report p. 132 - 135)

Results and discussion

Test results
Key result
Sex:
male
Genotoxicity:
negative
Toxicity:
not specified
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid

Any other information on results incl. tables

For single and repeated dosage of 15, 15, and 150 mg/kg bw (Report p. 80 - 99) as well as single and repeated dosage of 5000 mg/kg bw (Report p. 100 - 117),there was no dose-response and time-trend pattern of effects following the silicate treatment: The values calculated for reproduction parameters (see "Examinations" above) that related to the treated animals did not significantly vary from those obtained from the negative controls, whereas TEM caused a significant preimplantation loss and embryo resorption during the first five weeks.

Applicant's summary and conclusion

Conclusions:
Interpretation of results: negative