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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro cytogenicity / chromosome aberration study in mammalian cells
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Study period:
1974
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study was conducted using a method similar to OECD Testing Guideline 473 and meets acceptable scientific standards.

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
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Deviations:
yes
Remarks:
Study performed without metabolic activation using a non-standard cell lines (WI-38 - human embryonic lung cultures)
GLP compliance:
no
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Constituent 1
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
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): FDA 71-45 (Sodium silicoaluminate)
- Physical state: Fine white powdered material
- Lot/batch No.: SR-1621

Method

Species / strain
Species / strain / cell type:
mammalian cell line, other: WI-38 - human embryonic lung cultures
Details on mammalian cell type (if applicable):
- Type and identity of media: Not provided
- Properly maintained: yes
- Periodically checked for Mycoplasma contamination: yes
- Periodically checked for karyotype stability: Not provided
- Periodically "cleansed" against high spontaneous background: Not provided
Metabolic activation:
without
Test concentrations with justification for top dose:
1, 10 and 100 µg/ml
Vehicle / solvent:
- Vehicle: 0.85 saline
Controls
Negative solvent / vehicle controls:
yes
Remarks:
Saline solution
Positive controls:
yes
Positive control substance:
triethylenemelamine
Remarks:
0.1 µg/ml
Details on test system and experimental conditions:
METHOD OF APPLICATION: in suspension

DURATION
- Exposure duration: 24 - 48 h

STAIN: acetic acid-orcein stain (20%)

NUMBER OF REPLICATIONS: 3 per concentration

NUMBER OF CELLS EVALUATED: 100 per concentration

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index

OTHER EXAMINATIONS:
- Determination of polyploidy
Evaluation criteria:
Evaluation of the genetic damage by identification of the aberrations (bridges, pseudochiasmata, multipolar cells, acentric fragments, etc) induced by the test substance.
Statistics:
Not provided

Results and discussion

Test results
Species / strain:
mammalian cell line, other: WI-38 - human embryonic lung cultures
Metabolic activation:
without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
250 µg/ml
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Additional information on results:
Acentric fragments:
- Negative control: 2%
- 1 µg/ml: 0%
- 10 µg/ml: 1%
- 100 µg/ml: one cell with an acentric fragment and one cell with a bridge (non significant).
- Positive control: four cells with pulverization together with the other aberrations.
Remarks on result:
other: strain/cell type: WI-38 - human embryonic lung cultures
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

The test item was considered to be non-mutagenic under the conditions of the test.
Executive summary:

The in vitro cytogenicity in mammalian cells of the read-across substance sodium silicoaluminate branded as FDA 71-45 was determined according to a method similar to the OECD Guideline for Testing of chemicals 473. Chromosome aberrations were evaluated in WI-38 - human embryonic lung cultures without metabolic evaluation.

The in vitro mammalian chromosome aberration test was performed with concentrations of 1, 10 and 100 µg/ml in a saline solution at 0.85%. Anaphase preparations were made by growing the WI-38 cells in presence of the test item. Cells were then suspended in acetic acid-orcein stain (20%) and put in slides to be evaluated. Evaluation of the genetic damage was made by identification of the aberrations induced by the test item.

Cytotoxicity was observed at a concentration of 250 µg/ml. No significant numbers of aberration were observed for each tested concentration.

The test item was considered to be non-mutagenic under the conditions of the test.