Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
no data available
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Essential details given; well-documented publication, although no positive control substance was stated/used.

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
Primary mutagenicity screening of food additives used in japan
Author:
Ishidate, M.; et al.
Year:
1983
Bibliographic source:
Food Chem. Toxicol. 8, 623-636
Reference Type:
publication
Title:
Methods for detecting carcinogens and mutagens with the Salmonella/mammalian-microsome mutagenicity test.
Author:
Ames, B.N.; et al.
Year:
1975
Bibliographic source:
Mutation Research 31, 347-364

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Reverse mutation assays using Salmonella typhimurium strains TA92, TA1535, TA100, TA1537, TA94 and TA98 were carried out according to the method of Ames, McCann & Yamasaki (1975).
GLP compliance:
no
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Sodium disulphite, anhydrous
- Substance type: pure active substance
- Physical state: solid
- Analytical purity: 95 %
No further details are given.

Method

Target gene:
not applicable
Species / strainopen allclose all
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Additional strain characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9-mix
Species / strain:
other: TA 92 and TA 94
Additional strain characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9-mix
Test concentrations with justification for top dose:
six test concentrations, up to 50 mg/plate
Vehicle:
- Vehicle(s)/solvent(s) used: phosphate buffer
- Justification for choice of solvent/vehicle: no data
Controls
Negative controls:
no
Solvent controls:
yes
Remarks:
phosphate buffer
True negative controls:
no
Positive controls:
not specified
Positive control substance:
not specified
Details on test system and conditions:
METHOD OF APPLICATION: in agar (preincubation)

DURATION
- Preincubation period:20 minutes at 37°C
- Exposure duration: 48 hours at 37°C

NUMBER OF REPLICATIONS: Duplicate plates were used for each of the 6 different concentrations of the test item.

EVALUATION: The number of revertant (his+) colonies was scored.

DETERMINATION OF CYTOTOXICITY
- Method: no data

Evaluation criteria:
The result was considered positive if the number of colonies found was twice the number in the control (vehicle control).
Statistics:
Statististical analysis is not mandatory for this test.

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
not specified
Vehicle controls valid:
yes
Negative controls valid:
not specified
Positive controls valid:
not specified
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.
Species / strain:
other: TA 92 and TA 94
Metabolic activation:
with and without
Genotoxicity:
negative
Remarks:
No significant increases in the numbers of revertant colonies were detected in any S. typhimurium strains at the highest dose tested.
Cytotoxicity:
not specified
Vehicle controls valid:
yes
Negative controls valid:
not specified
Positive controls valid:
not specified
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.
Additional information on results:
No further details are reported.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

Sodium bisulfite was negative in the Ames test, no significant increases in the number of revertant colonies were detected in any S. typhimurium strains at the maximum dose.
Executive summary:

Reverse mutation assays using Salmonella typhimurium strains TA92, TA1535, TA100, TA1537, TA94 and TA98 were carried out according to the method of Ames, McCann & Yamasaki (1975). The cells were preincubated with 6 different concentrations up to 50 mg/plate for 20 minutes before plating. Plates in duplicate were incubated for 2 days at 37°C, and then the number of revertant colonies were counted. The result was considered positive if the number of colonies found was twice the number in the vehicle control (phosphate buffer).

Sodium disulfite was negative in the Ames test, no significant increases in the number of revertant colonies were detected in any S. typhimurium strains at the maximum dose.