Merbromin

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

AMES assay

The test substance substance did not showed any mutagenic activity at concentrations up to 100 μg/plate in S.typhimurium strains TA1535, TA100, TA1537, TA1538 and TA98 in the presence and absence of S9 metabolic activation system and hence, it can be concluded that the test substance  is non mutagenic.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

data from handbook or collection of data

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: As mention below

Principles of method if other than guideline:

Weight of evidence prepared from various publication mention below.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Target gene:

Histidine

Species / strain / cell type:

S. typhimurium, other: TA1535, TA100, TA1537, TA1538,TA98

Details on mammalian cell type (if applicable):

Not applicable.

Additional strain / cell type characteristics:

not specified

Species / strain / cell type:

S. typhimurium, other: TA1535, TA100, TA1537, TA1538,TA98

Metabolic activation:

with and without

Metabolic activation system:

Liver-microsome preparation from rats injected with Aroclor 1254, 0.25 ml "S-9 mix"-plate with 0.2 ml S9/ml 'S9 mix'.

Test concentrations with justification for top dose:

1,10,50 and 100 µg/plate
2,33 .0µg/plate,100 .0µg/plate,333.0 µg/plate,1000.0µg/plate,3333.0µg/plate

Vehicle / solvent:

DMSO

Untreated negative controls:

yes

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

9-aminoacridine

ethylmethanesulphonate

methylmethanesulfonate

other: Anthragallol (For strains TA-1538 and TA98 without S9); 2-Anthramine (For all strains with S9)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar

DURATION
- Preincubation period: No data available
- Exposure duration:3 days

Evaluation criteria:

Mutations in Salmonella typhimurium i.e. Number of His + Revertants/plate

Statistics:

Rounded mean ± standard deviation

Species / strain:

S. typhimurium, other: TA1535, TA100, TA1537, TA1538 and TA98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: Slight toxicity was noted

Vehicle controls validity:

not specified

Untreated negative controls validity:

valid

Positive controls validity:

valid

Species / strain:

S. typhimurium, other: TA1535, TA100, TA1537, TA1538 and TA98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Additional information on results:

COMPARISON WITH HISTORICAL CONTROL DATA: Yes, historical negative control were used.

Remarks on result:

other: no mutagenic potential

Conclusions:

The test substance substance did not showed any mutagenic activity at concentrations up to 100 μg/plate in S.typhimurium strains TA1535, TA100, TA1537, TA1538 and TA98 in the presence and absence of S9 metabolic activation system and hence, it can be concluded that the test substance is non mutagenic.

Executive summary:

The Ames Salmonella/mammalian-microsome assay was used to evaluate the bacterial mutagenicity of test substance . The test substance did not showed any mutagenic activity at concentrations up to 100 μg/plate in S.typhimurium strains TA1535, TA100, TA1537, TA1538 and TA98 in the presence and absence of S9 metabolic activation system and hence test substance is not likly to be classified as mutagen.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Data for the various test chemicals was reviewed to determine the mutagenic nature of Merbromin (129-16-8). The studies are as mentioned below:

AMES test

The Ames Salmonella/mammalian-microsome assay was used to evaluate the bacterial mutagenicity of test substance. The test substance did not showed any mutagenic activity at concentrations up to 100 μg/plate in Salmonella typhimurium strains TA1535, TA100, TA1537, TA1538 and TA98 in the presence and absence of S9 metabolic activation system and hence the test substance is non genotoxic.

Bacterial gene mutation assay was performed for the test material in Salmonella typhimuriumTA1535, TA1537, TA1538, TA100 and TA98 strains at a dose range of 33.0, 100.0, 333.0, 1000.0and3333.0µg/plate by Plate-incorporation method.Chemical was tested without metabolic activation and with S9 mix from Aroclor 1254-induced male Fischer 344 rats and Syrian golden hamsters. Appropriate positive and solvent controls were also incorporated in the study.Test substance failed to induce gene mutation in the bacterial strains TA1535, TA1537, TA1538, TA100 and TA98.

Based on the data summarized, test substance did not induce gene mutation .Hence it is not likely to be mutagenic in vitro.Thus based on the above annotation and CLP criteria the test chemical did not induce gene mutation .Hence it is not likely to be classified as mutagenic in vitro.

Justification for classification or non-classification

Thus based on the above annotation and CLP criteria the test chemical did not induce gene mutation .Hence it is not likely to be classified as mutagenic in vitro.