Disodium oxybis[methylbenzenesulphonate]

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study according OECD 476

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

GLP compliance:

yes

Type of assay:

mammalian cell gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Disodium oxybis[methylbenzenesulphonate]

EC Number:

277-242-0

EC Name:

Disodium oxybis[methylbenzenesulphonate]

Cas Number:

73037-34-0

Molecular formula:

C14H12Na2O7S2

IUPAC Name:

disodium oxybis(methylbenzenesulfonate)

Test material form:

solid

Details on test material:

Active content reported: 90-95 %

Method

Target gene:

HPRT locus

Species / strain

Species / strain / cell type:

Chinese hamster lung fibroblasts (V79)

Additional strain / cell type characteristics:

other: These cells are characterized by their high proliferation rate (12-14 h doubling time) and their high plating efficiency of untreated cells.

Metabolic activation:

with and without

Metabolic activation system:

S9 mix was prepared from livers of male Wistar rats that were induced by oral applications of phenobarbital and ß-naphthoflavone on 3 consecutive days.

Test concentrations with justification for top dose:

EXPERIMENT I
without S9-mix (4 hour treatment):
0.06, 0.13, 0.5, 1.0, 2.0, 4.0, 6.0, 8.0 and 10 mM
with S9-mix (4 hour treatment)
0.06, 0.13, 0.5, 1.0, 2.0, 4.0, 6.0, 8.0 and 10 mM

EXPERIMENT II
without S9-mix (20 hour treatment)
1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0 and 10 mM
with S9-mix (4 hour treatment)
3.25, 4.0, 4.75, 5.5, 6.25, 7.0, 7.75, 8.5, 9.25 and 10 mM

Vehicle / solvent:

treatment medium:
MEM and no FBS for the 4 hour treatment
MEM with 10 % FBS for the 20 hour treatment

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: Without metabolic activation: EMS (= ethylmethane sulfonate) With metabolic activation: DMBA (= 7,12-dimethylbenz(a)anthracene)

Details on test system and experimental conditions:

The assay was performed in 2 independent experimentsm using 2 parallel cultures each.
The first main experiment was performed with and without liver microsomal activation and a treatment period of 4 hours.
The second experiment was performed with a treatment time of 4 hours with and 20 hours without metabolid activation.

Evaluation criteria:

A test is considered to be negative if there is no biological relevant increase in the number of mutants.
A test is considered positive with a reproducible three times higher mutation frequency than the solvent control or a concentration relateted increase in mutation frequency.

Statistics:

no

Results and discussion

Test results

Species / strain:

Chinese hamster lung fibroblasts (V79)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Remarks:

At 64 µg/ml and above in the first and the second experiment in the presence of S9-mix. At 0.5 µg/ml and above in the second experiment without S9-mix.

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: other: Chinese hamster lung fibroblasts (V79)

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

No substantial and reproducible dose dependent increase of the mutation frequency was observed in both main experiments.

Appropriate reference mutagens, used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test system and the activity of the metabolic activation system.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

In conclusion it can be stated that under the reported experimental conditions ditolylether disulfonic acid disodium salt, isomer mixture did not induce gene mutations at the HPRT locus in V79 cells.
Therefore, ditolylether disulfonic acid disodium salt, isomer mixture is considered to be non-mutagenic in this HPRT assay.

Executive summary:

The study was performed to investigate the potential of ditolylether disulfonic acid disodium salt, isomer mixture to induce gene mutations at the HPRT locus in V79 cells of the Chinese hamster according to OECD TG 476.

The assay was performed in two independent experiments, using two parallel cultures each. The first main experiment was performed with and without liver microsomal activation and a treatment period of 4 hours. The second experiment was performed with a treatment time of 4 hours with and 20 hours without metabolic activation. No precipitation of the test item was noted in the experiments. No substantial and reproducible dose dependent increase of the mutation frequency was observed in both main experiments. Appropriate reference mutagens, used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test system and the activity of the metabolic activation system.

In conclusion, under the reported experimental conditions ditolylether disulfonic acid disodium salt, isomer mixture is considered to be non-mutagenic in the HPRT-locus using V79 cells of the Chinese Hamster.