Potassium superoxide

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Mutagenicity spectra in Salmonella typhimurium strains of glutathione, L-cysteine and active oxygen species

Author:

Glatt H

Year:

1989

Bibliographic source:

Mutagenesis. 4(3): 221-227

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Potassium superoxide

EC Number:

234-746-5

EC Name:

Potassium superoxide

Cas Number:

12030-88-5

Molecular formula:

KO2

IUPAC Name:

potassium; molecular oxygen

Test material form:

solid

Method

Target gene:

Histidine

Species / strain

Species / strain / cell type:

S. typhimurium, other: TA 92, TA 97, TA 100, TA 102, TA 104, TA 1535, and TA 1537

Metabolic activation:

without

Metabolic activation system:

S9 fractions from male Sprague-Dawley rat kidneys

Test concentrations with justification for top dose:

0, 0.33, 0.67, 1.33, 2.67 and 5.33 µmol/plate

Vehicle / solvent:

neutralized aqueous solution

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

no

Details on test system and experimental conditions:

Method of application: in agar (plate incorporation) + 'Preincubation assay' (20 min incubation in a glass tube)
Number of replications: 3
All strains/cell types tested

Statistics:

Linear regression analysis

Results and discussion

Test results

Key result

Species / strain:

S. typhimurium, other: TA 92, TA 97, TA 100, TA 102, TA 104, TA 1535, and TA 1537

Metabolic activation:

without

Genotoxicity:

positive

Remarks:

Positive in S. typhimurium TA 100, TA 102, and TA 104

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

not applicable

Additional information on results:

Salmonella typhymurium strain TA 104 was the most responsive strain. Marked effects were observed in TA 102 as well. In strain TA 100, the test substance only produced a weak increase in the number of mutants. No mutagenicity was observed in the other strains. The spectra of mutagenicity was similar for KO2, H2O2, and glucose oxidase, all being directly or indirectly generators of reactive oxygen species.

Applicant's summary and conclusion

Conclusions:

Under the study conditions, the substance was found to be mutagenic in Salmonella typhimurium.

Executive summary:

A study was conducted to determine the in vitro genetic toxicity of the substance according to OECD Guideline 471. Salmonella typhimurium strains TA 97, TA 100, TA 102, TA 104, TA 1535, and TA 1537 were treated with the test substance using the plate incorporation method with a 'preincubation assay' (20 min) at concentration ranges of 0 - 5.33 µmol/plate without metabolic activation. The exposure to the test substance produced mutagenic response in S. typhimurium strains TA 100, TA 102, and TA 104, with more marked effects in TA 102 and 104. Salmonella typhimurium strain TA 104 was the most responsive strain. Marked effects were observed in TA 102 as well. In strain TA 100, the test substance only produced a weak increase in the number of mutants. No mutagenicity was observed in the other strains. The strain spectra of the mutagenicity were similar for KO2, H2O2, and glucose oxidase, all being directly or indirectly generators of reactive oxygen species. Under the study conditions, the substance was found to be mutagenic in Salmonella typhimurium (Glatt, 1989).