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Diss Factsheets

Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / bone marrow chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for type of information:
Test material ist different from reference substance but comparable, see chapter 13, attachment 'Analogue Approach Justification'
Cross-reference
Reason / purpose for cross-reference:
read-across: supporting information

Data source

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

Materials and methods

Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
The host organism is inoculated by intraperitoneal injection with a common indicator microorganism/tester strain before treatment with the test substance. After "incubation" in the host organism, the tester strain is withdrawn from the ascites and tested for mutation on minimal agar plate., e.g. accroding to Ames.
GLP compliance:
not specified
Type of assay:
other: host mediated assy

Test material

Constituent 1
Chemical structure
Reference substance name:
Silicic acid, aluminum sodium salt
EC Number:
215-684-8
EC Name:
Silicic acid, aluminum sodium salt
Cas Number:
1344-00-9
Molecular formula:
AlNaO6Si2
IUPAC Name:
aluminium(3+) sodium bis(oxosilanebis(olate))
Details on test material:
Other Test Substance
SIPERNAT 820A, sodium aluminium silicate (Degussa) [CAS No. 1344-00-9]
Chemical formula: 1.2Na2O x Al2O3 x 13.4SiO2
Degree of Purity: ~99 %
Water solubility: 48 mg/L
Specific details on test material used for the study:
FDA-Compound 71-45, "sodium silicoaluminate",
synthetic silica
Lot no. SR-1621

Test animals

Species:
mouse
Strain:
ICL-ICR
Sex:
male

Administration / exposure

Route of administration:
oral: gavage
Details on exposure:
Type: Salmonella typhimurium reverse mutation assay
Method: The test substance was administered orally to 10 host animals per dose. In the acute study the bacteria (Salmonella typhimurium TA 1530 and his G-46)were inocculated i.p. after the administration of the test substance. In the subacute study the bacteria were injected after the last administration of the test substance. Negative (0.85 % saline) and positive (100 mg/kg dimethylnitrosamine) controls were run in parallel. The animals were sacrificed three hours after administration and the bacteria were removed from the peritoneal cavity. The induction of reverse mutation was quantified on agar plates. 
Duration of treatment / exposure:
single administration ("acute") and repeated administration (5 times, "subacute")
Frequency of treatment:
1x and 5x (1x/d)
Doses / concentrationsopen allclose all
Dose / conc.:
4.25 mg/kg bw/day (nominal)
Remarks:
suspended in 0.85 % saline, administered 1x/d (Test I)
Dose / conc.:
42.5 mg/kg bw/day (nominal)
Remarks:
suspended in 0.85 % saline, administered 1x/d (Test I)
Dose / conc.:
425 mg/kg bw/day (nominal)
Remarks:
suspended in 0.85 % saline, administered 1x/d (Test I)
Dose / conc.:
5 000 mg/kg bw (total dose)
Remarks:
suspended in 0.85 % saline (Test II)
No. of animals per sex per dose:
10 (males only)
Control animals:
yes, concurrent vehicle
Positive control(s):
yes, treated with 100 mg/kg bw Dimethylnitrosamine (DMN)

Results and discussion

Test results
Key result
Sex:
male
Genotoxicity:
negative
Toxicity:
not examined
Positive controls validity:
valid
Additional information on results:
There was a high increase in mutants following oral treatment with Dimethylnitrosamine (DMN), but no significant increases in mutation rates at any dose and dose regimen.

Applicant's summary and conclusion

Conclusions:
There was a high increase in mutants following oral treatment with DMN, but no significant increases in mutation rates at any dose and dose regimen.