Disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Genetic toxicity in vitro:
Chocolate Brown HT ( Disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate) is considered to be not genotoxic in the bacteria Salmonella typhimurium TA 1538 and Escherichia coli WP2 uvrA since no detectable effects were observed in the Modified liquid Fluctuation test.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from a peer reviewed publication

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Modified liquid Fluctuation test

GLP compliance:

not specified

Type of assay:

bacterial gene mutation assay

Species / strain / cell type:

S. typhimurium TA 1538

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S9

Test concentrations with justification for top dose:

5000 mg/L

Vehicle / solvent:

Deionised water

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

not specified

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Preincubation period: No data available
- Exposure duration: 72- 96 hrs
- Expression time (cells in growth medium): 72- 96 hrs
- Selection time (if incubation with a selection agent): No data available
- Fixation time (start of exposure up to fixation or harvest of cells): No data available

SELECTION AGENT (mutation assays): No data available
SPINDLE INHIBITOR (cytogenetic assays): No data available
STAIN (for cytogenetic assays): No data available

NUMBER OF REPLICATIONS: No data available

NUMBER OF CELLS EVALUATED: No data available

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index; cloning efficiency; relative total growth; other: No data available

OTHER EXAMINATIONS:
- Determination of polyploidy: No data available
- Determination of endoreplication: No data available
- Other: No data available

OTHER: The food colour was made up in deionized water and membrane-sterilized prior to use. The test material was tested at its maximum sublethal concentration.

Evaluation criteria:

The test material was considered positive only if it resulted in significant more turbid tubes in a treated series when compared with an untreated set of tubes

Statistics:

Chi square test

Key result

Species / strain:

S. typhimurium TA 1538

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:

not specified

Key result

Species / strain:

E. coli WP2 uvr A

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:

not specified

Remarks on result:

other: allno mutagenic potential

Conclusions:

Chocolate Brown HT ( Disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate) is considered to be not genotoxic in the bacteria Salmonella typhimurium TA 1538 and Escherichia coli WP2 uvrA since no detectable effects were observed in the Modified liquid Fluctuation test.

Executive summary:

Bacterial gene mutation was studied using Modified liquid Fluctuation test. Chocolate Brown HT ( Disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate) was used at a concentration of 5000 mg/kg and its genotoxic effect was studied in the bacteria Salmonella typhimurium TA 1538 and Escherichia coli WP2 uvrA. Te fluctuation assay in the liquid medium was conducted for 72-96 hrs at 25°C. The assay was performed for each bacterium in three separate experiments. The given test material is negative for inducing genotoxicity in the bacteria Salmonella typhimurium TA 1538 and Escherichia coli WP2 uvrA indicating that the substance is non-genotoxic.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Genetic toxicity in vitro:
Based on the available data for In vitro genetic toxicity of the target substance disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate the following results are summarized:

In key study, Bacterial gene mutation was studied using Modified liquid Fluctuation test. Chocolate Brown HT ( Disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate) was used at a concentration of 5000 mg/kg and its genotoxic effect was studied in the bacteria Salmonella typhimurium TA 1538 and Escherichia coli WP2 uvrA. Te fluctuation assay in the liquid medium was conducted for 72-96 hrs at 25°C. The assay was performed for each bacterium in three separate experiments. The given test material is negative for inducing genotoxicity in the bacteria Salmonella typhimurium TA 1538 and Escherichia coli WP2 uvrA indicating that the substance is non-genotoxic.

While in supporting study, Chocolate Brown HT ( Disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate) was used at a concentration of 5000 mg/kg and its genotoxic effect was studied in the bacteria E. coli strains WP2 trp uvrA and WP100 trp uvrA recA by rec plate assay in the agar medium. The plates were incubated overnight at 37°C. The given test material is negative for genotoxicity in the bacteria E. coli strains WP2 trp uvrA and WP100 trp uvrA recA indicating that the substance is non-genotoxic.

Based on the studies summarized above it can be observed that the substance Chocolate Brown HT ( Disodium 4,4'-[[2,4-dihydroxy-5-(hydroxymethyl)-1,3-phenylene]bis(azo)]bisnaphthalene-1-sulphonate) failed to induce mutation in Salmonella typhimurium and E.coli bacterium species. Hence it is concluded that the target substance is not classified under In vitro genetic toxic category.

Justification for classification or non-classification

Based on the available information from reliable sources, the substance is likely to be non-genotoxic.