potassium ferrite

Genetic toxicity: in vitro

Administrative data

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:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant guideline study, available as unpublished report, no restrictions, fully adequate for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)

Test guideline 3

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Test guideline 4

Qualifier:

according to guideline

Guideline:

EPA OTS 798.5265 (The Salmonella typhimurium Bacterial Reverse Mutation Test)

Test guideline 5

Qualifier:

according to guideline

Guideline:

EPA OTS 798.5100 (Escherichia coli WP2 and WP2 UVRA Reverse Mutation Test)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

430-010-4

EC Name:

-

Cas Number:

12160-44-0

Molecular formula:

K2Fe22O34

IUPAC Name:

hydrate iron potassium hydride

Details on test material:

- Name of test material (as cited in study report): Potassium ferrite
- Physical state: Reddish brown powder
- Composition of test material, percentage of components: K2Fe22O34; 83,8%, K2Fe10O16; 6.2%, K2CO3 1.5H2O; 10.0%
- Lot/batch No.: 23388-17 CG20X 407448A
- Expiration date of the lot/batch: 6 August 1997
- Storage condition of test material: Room temperature, dark, desiccated

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

E. coli, other: CM891

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254-induced rat liver S9.

Test concentrations with justification for top dose:

Concentration range in the range finding test: 5, 15, 50, 150, 500, 1500 and 5000 µg/plate
Concentration range in the main test: 50, 150, 500, 1500 and 5000 µg/plate

Vehicle / solvent:

Solvent: purified water

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

Remarks:

TA 98, TA 100, TA 1537 with metabolic activation

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2 -Aminoanthracene

Remarks:

TA 1535, CM891 with metabolic activation

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

TA 1537, without metabolic activation

Controls 4

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

TA98, without metabolic activation

Controls 5

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

N-ethyl-N-nitro-N-nitrosoguanidine

Remarks:

CM891, TA100, TA1535, without metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION:
Potassium ferrite was prepared in purified water.
Range finder: Where appropriate, 0.5 mL rat liver microsomal preparation (S9 mix) or 0.1 M sodium phosphate buffer was added to each tube. Molten top-agar (2 mL) containing 0.5 mM histidine/0.5 mM biotin or 0.5 mM tryptophan, maintained at 45°C, and bacterial culture (0.1 mL) were then added, the tubes were inverted to mix thoroughly and the contents poured onto plates containing solidified minimal medium (25 mL).

Second test:
Aliquots (0.1 mL) of each concentration of Potassium ferrite were placed in sterile glass tubes, followed by 0.5 mL rat liver microsomal preparation (S9 mix) or 0.1 M sodium phosphate buffer where appropriate. Bacterial
culture (0.1 mL) was then added and the tubes were mixed by inversion. The mixtures were preincubated for 30 minutes at 37 °C with shaking prior to addition of molten top-agar (2 mL) containing 0.5 mM histidine/0.5 mM biotin or 0.5 mM tryptophan, maintained at 45°C. The tubes were again inverted to mix thoroughly and the contents poured onto plates containing solidified minimal medium (25 ml).

DURATION
- Preincubation period: 30 minutes
- Exposure duration: 3 days


NUMBER OF REPLICATIONS:
All plates were prepared in triplicates

Evaluation criteria:

A test article is considered as positive if either a significant dose-related increase in the number of revertants or a significant and reproducible increase for at least one test concentration is induced.
A test article producing neither a significant dose-related increase in the number of revertants nor a significant and reproducible positive response at any one of the test points is considered non-mutagenic in this system.

Statistics:

No evaluated statistical procedure can be recommended for analysis of data from the bacterial assays at this time.

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A pKM 101

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

FIRST (RANGE-FINDING) TEST:
- Sterility checks, spontaneous reversion rate and viability checks: The absence of colonies on Potassium ferrite and S9 mix sterility check plates indicates that these preparations were free of microbial contamination. The counts recorded on appropriate negative control plates confirmed the characteristically low spontaneous reversion rates of the tester strains and the absence of effects on these rates of purified water inclusion.
- Mutagenic activity of positive control chemicals: Appropriate positive control chemicals (with S9 mix where required) induced marked increases in revertant colony numbers with all strains, confirming sensitivity of the cultures and activity of the S9 mix.
- Effect of Potassium ferrite: No increases in revertant colony numbers over control counts were obtained with any of the tester strains following exposure to Potassium ferrite at concentrations from 5 to 5000 µg/plate in either the presence or absence of S9 mix. No visible thinning of the background lawn of non-revertant cells was obtained following exposure to Potassium ferrite. A top exposure concentration of 5 mg/plate was therefore selected for use in the second test.
MAIN TEST:
- Sterility checks, spontaneous reversion rate and viability checks: The absence of colonies on Potassium ferrite and S9 mix sterility check plates indicates that these preparations were free of microbial contamination. The counts recorded on appropriate negative control plates confirmed the characteristically low spontaneous reversion rates of the tester strains and the absence of effects on these rates of purified water inclusion.
-Mutagenic activity of positive control chemicals: Appropriate positive control chemicals (with S9 mix where required) induced marked increases in revertant colony numbers with all strains, confirming sensitivity of the cultures and activity of the S9mix. - Effect of Potassium ferrite: No increases in revertant colony numbers over control counts were obtained with any of the tester strains following exposure to Potassium ferrite at concentrations from 50 to 5000 µg/plate in either the presence or absence of S9 mix.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

It is cocluded that Potassium ferrite did not exhibit any mutagenic activity under the conditions of the test.