[No public or meaningful name is available]

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Guideline study, 2019

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

catena-((μ4-sulfato)-(μ2-glycinato)-manganese

Cas Number:

2087529-10-8

Molecular formula:

Mn(SO4)(C2H5NO2)

IUPAC Name:

catena-((μ4-sulfato)-(μ2-glycinato)-manganese

Test material form:

solid

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S-9

Test concentrations with justification for top dose:

0. 16, 50, 160, 500, 1600, 5000 ug/plate with S-9
Independant repeats with and without S-9 at 1600 and 5000 ug/plate

Vehicle / solvent:

Water for test substance and DMSO for positive controls

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

Water for test substance and DMSO for positive controls

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

sodium azide

methylmethanesulfonate

other:

Rationale for test conditions:

Following OECD guideline and national Regulations

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not applicable

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not applicable

Positive controls validity:

valid

Test results 4

Species / strain:

E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not applicable

Positive controls validity:

valid

Test results 5

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

No adverse effects for genetic toxicity or cytotoxicity up to the maximum tested treatment levels of 5000 ug/plate (maximum set by guidelines)

Any other information on results incl. tables

The experiments were carried out using histidine-requiring auxotroph strains of Salmonella typhimurium (Salmonella typhimurium TA98, TA100, TA1535 and TA1537), and the tryptophan-requiring auxotroph strain of Escherichia coli (Escherichia coli WP2 uvrA) in the presence and absence of a post mitochondrial supernatant (S9) prepared from livers of Phenobarbital/β-naphthoflavone-induced rats.

The study included a preliminary solubility test, a preliminary concentration range finding test (informatory toxicity test following the plate incorporation method), an initial mutation test (plate incorporation test), and a confirmatory mutation test (pre-incubation test).

Based on the results of the solubility test and the concentration range finding test, the test item was dissolved in ultrapure water (ASTM Type I), and the following concentrations were prepared and investigated in the initial and confirmatory mutation tests in the absence and presence of exogenous metabolic activation:

±S9: 5000; 1600; 500; 160; 50 and 16 μg/plate.

The selection of the concentration range was based on the recommendations in OECD 471 guideline [6]. The maximum test concentration was in all strains 5000 μg/plate, as recommended in the guideline for soluble non-toxic compounds.

Slight precipitate was noticed after about 48 hours incubation on the plates in all examined strains at the highest examined concentration of 5000 μg/plate in the absence and presence of S9 (±S9), following the plate incorporation procedure and at 5000 and 1600 μg/plate in the absence and presence of S9 (±S9) following the pre-incubation procedure. The obtained precipitate did not interfere with the scoring of the colonies and background lawn development.

In the performed experiments inhibitory effect of the test item on bacterial growth was not observed. All of the noticed lower revertant colony numbers (when compared to the revertant colony numbers of the corresponding vehicle control) remained in the range of the biological variability of the applied test system and the background lawn development was not affected in any case.

The number of revertant colonies in the vehicle control (ultrapure water) plates with and without S9 Mix was within the historical control data ranges for the number of spontaneous revertant colonies per strain.

The positive control reference items induced the expected, biological relevant increases (more than 3-fold increase) in revertant colonies and the number of revertants was within the historical control data range per strain, thereby meeting the criteria for a valid positive control in both experimental phases and all tester strains.

No biologically relevant increases were observed in the number of revertant colonies in any of the five tester strains following treatment with MANGANESE GLYCINATE at any concentration levels, either in the presence or absence of S9 Mix in the performed experiments.

Applicant's summary and conclusion

Conclusions:

Based on the results obtained under the experimental conditions applied, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.
In conclusion, the test item MANGANESE GLYCINATE has no mutagenic activity in the bacterial tester strains under the test conditions used in this study.
The results are as expected when taking into account the absence of known mutagenic activity of Mn, Sulphate or Glycinate ions.