Registration Dossier

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)
Deviations:
no
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder

Method

Species / strain
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Metabolic activation:
with and without
Metabolic activation system:
S9 Mix
Test concentrations with justification for top dose:
The test item concentrations to be applied in the main experiments were chosen according to the results of the pre-experiment. 1000 μg/plate was selected as the maximum concentration. The concentration range covered two logarithmic decades. Two independent experiments were performed with the following concentrations:
Experiment I:
3.16, 10.0, 31.6, 100, 316 and 1000 μg/plate in addition: 1.00 μg/plate for TA 1535, TA 1537 and TA 102
Experiment II:
1.58, 5.0, 15.8, 50, 158 and 500 μg/plate
As the results of the pre-experiment were in accordance with the criteria described above, these were reported as a part of the main experiment I.
Vehicle:
The test item was suspended in ethanol, processed by ultrasound for 5 min at 37 °C and diluted
prior to treatment. The solvent was compatible with the survival of the bacteria and the S9 activity.
Controls
Negative controls:
yes
Remarks:
A. dest., Eurofins Munich, Lot No. 170220)
Solvent controls:
yes
Remarks:
ethanol, AppliChem Lot No. 5Y013701
Positive controls:
yes
Positive control substance:
sodium azide
methylmethanesulfonate
other: 4-nitro-o-phenylene-diamine; 2-aminoanthracene

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 1537
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
S. typhimurium TA 1535
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
S. typhimurium TA 102
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Additional information on results:
Precipitation of the test item was observed in all tester strains used in experiment I (with and
without metabolic activation) at a concentration of 1000 μg/plate.

Applicant's summary and conclusion

Conclusions:
In conclusion, it can be stated that during the described mutagenicity test and under the experimental conditions reported, Basic Yellow 1 did not cause gene mutations by base pair changes or frameshifts in the genome of the tester strains used. Therefore, Basic Yellow 1 is considered to be non-mutagenic in this bacterial reverse mutation assay.
Executive summary:

In order to investigate the potential of Basic Yellow 1 for its ability to induce gene mutations the plate incorporation test (experiment I and II) was performed with the Salmonella typhimurium strains

TA 98, TA 100, TA 1535, TA 1537 and TA 102.

In two independent experiments several concentrations of the test item were used. Each assay was conducted with and without metabolic activation. The concentrations, including the controls, were tested in triplicate. The following concentrations of the test item were prepared and used in the experiments:

Experiment I:

3.16, 10.0, 31.6, 100, 316 and 1000 μg/plate in addition: 1.00 μg/plate for TA 1535, TA 1537 and TA 102

Experiment II:

1.58, 5.0, 15.8, 50, 158 and 500 μg/plate

Precipitation was observed in all tester strains used in experiment I (with and without metabolic activation).

Toxic effects of the test item were noted in all tester strains used in experiment I and II:

- In experiment I toxic effects of the test item were observed at concentrations of 316 μg/plate and higher (with and without metabolic activation) depending on the particular tester strain.

- In experiment II toxic effects of the test item were noted at a concentration of 500 μg/plate (with and without metabolic activation) in all tester strains tested.

No biologically relevant increases in revertant colony numbers of any of the five tester strains were observed following treatment with Basic Yellow 1 at any concentration level, neither in the presence

nor absence of metabolic activation in experiment I and II.

All criteria of validity were met.

Conclusion

In conclusion, it can be stated that during the described mutagenicity test and under the experimental conditions reported, Basic Yellow 1 did not cause gene mutations by base pair changes or frameshifts in the genome of the tester strains used. Therefore, Basic Yellow 1 is considered to be non-mutagenic in this bacterial reverse mutation assay.