3-Oxazolidineethanol, 2-(1-methylethyl)-

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Incozol 3 is determined to be non-mutagenic in the Ames test with and without metabolic activation.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2007-05-14 to 2007-11-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

1997

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not applicable

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

Induced liver S9-mix (phenobarbitone/p-naphthoflavone (80/100 mg per kg per day) prior to S9 preparation)

Test concentrations with justification for top dose:

0, 0.15, 0.5, 1.5, 5, 15, 50, 150, 500, 1500 and 5000 µg/plate in a preliminary toxicity test
50, 150, 500, 1500 and 5000 µg/plate in the mutation tests

Vehicle / solvent:

- Vehicle used: DMSO
- Justification for choice of vehicle: The test material was fully miscible in dimethyl sulphoxide at 50 mg/mL in solubility checks performed in-house.

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

N-ethyl-N-nitro-N-nitrosoguanidine

Remarks:

without S9 mix: N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG): TA100, TA1535, WP2uvrA-; 9-Aminoacridine (9AA): TA1537; 4-Nitroquinoline-l-oxide (4NQO): TA98

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

other: 2-aminoanthracene

Remarks:

with S9 mix: 2-Aminoanthracene (2AA): TA100, TA1535, TA1537, WP2uvrA-; Benzo(a)pyrene (BP): TA98

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 hours

SELECTION AGENT: Salmonella typhimurium: 0.05 mM histidine and 0.05 mM biotin, E. coli: 0.05 mM tryptophan

NUMBER OF PLATES: 3 per strain per concentration with and without S9-mix

REPLICATION: one

DETERMINATION OF BACTERIOTOXICITY
- Method: TA100 or WP2uvrA were incubated at 37 °C in the presence of test substance concentrations mentioned above. After approximately 48 hours the plates were assessed for numbers of revertant colonies using a Domino colony counter and examined for effects on the growth of the bacterial background lawn.

Evaluation criteria:

There are several criteria for determining a positive result, such as a dose-related increase in revertant frequency over the dose range tested and/or a reproducible increase at one or more concentrations in at least one bacterial strain with or without metabolic activation. Biological relevance of the results will be considered first, statistical methods, as recommended by the UKEMS can also be used as an aid to evaluation, however, statistical significance will not be the only determining factor for a positive response.
A test material will be considered non-mutagenic (negative) in the test system if the above criteria are not met.
Although most experiments will give clear positive or negative results, in some instances the data generated will prohibit a definitive judgement about the test material activity. Results of this type will be reported as equivocal.

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: not examined
- Effects of osmolality: not examined
- Evaporation from medium: not examined
- Water solubility: not examined
- Precipitation: none at 50 mg/mL in DMSO

COMPARISON WITH HISTORICAL CONTROL DATA: Yes

Conclusions:

The test material was considered to be non-mutagenic under the conditions of this test.

Executive summary:

The method conforms to the OECD Guidelines for Testing of Chemicals No. 471 "Bacterial Reverse Mutation Test", Method B13/14 of Commission Directive 2000/32/EC and the USA, EPA (TSCA) OPPTS harmonised guidelines.

Salmonella typhimurium strains TA1535, TA1537, TA98, TA100 and Escherichia coli strain WP2uvrA were treated with the test material using the Ames plate incorporation method at five dose levels, in triplicate, both with and without the addition of a rat liver homogenate metabolising system (10 % liver S9 in standard co-factors). The dose range was determined in a preliminary toxicity assay and was 50 to 5000 µg/plate in the first experiment. The experiment was repeated on a separate day using the same dose range as Experiment 1 with fresh cultures of the bacterial strains and fresh test material formulations.

The vehicle (dimethyl sulphoxide, DMSO) control plates gave counts of revertant colonies within the normal range. All of the positive control chemicals used in the test induced, marked increases in the frequency of revertant colonies both with and without metabolic activation. Thus, the sensitivity of the assay and the efficacy of the S9-mix were validated.

The test material caused no visible reduction in the growth of the bacterial background lawn at any dose level. The test material was, therefore, tested up to the maximum recommended dose level of 5000 µg/plate. No test material precipitate was observed on the plates at any of the doses tested in either the presence or absence of S9-mix. No significant increases in the frequency of revertant colonies were recorded for any of the bacterial strains, with any dose of the test material, either with or without metabolic activation. The test material was considered to be non-mutagenic under the conditions of this test.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Ames test:

The method conforms to the OECD Guidelines for Testing of Chemicals No. 471 "Bacterial Reverse Mutation Test", Method B13/14 of Commission Directive 2000/32/EC and the USA, EPA (TSCA) OPPTS harmonised guidelines.

Salmonella typhimurium strains TA1535, TA1537, TA98, TA100 and Escherichia coli strain WP2uvrA were treated with the test material using the Ames plate incorporation method at five dose levels, in triplicate, both with and without the addition of a rat liver homogenate metabolising system (10 % liver S9 in standard co-factors). The dose range was determined in a preliminary toxicity assay and was 50 to 5000 µg/plate in the first experiment. The experiment was repeated on a separate day using the same dose range as Experiment 1 with fresh cultures of the bacterial strains and fresh test material formulations.

The vehicle (dimethyl sulphoxide, DMSO) control plates gave counts of revertant colonies within the normal range. All of the positive control chemicals used in the test induced, marked increases in the frequency of revertant colonies both with and without metabolic activation. Thus, the sensitivity of the assay and the efficacy of the S9-mix were validated.

The test material caused no visible reduction in the growth of the bacterial background lawn at any dose level. The test material was, therefore, tested up to the maximum recommended dose level of 5000 µg/plate. No test material precipitate was observed on the plates at any of the doses tested in either the presence or absence of S9-mix.No significant increases in the frequency of revertant colonies were recorded for any of the bacterial strains, with any dose of the test material, either with or without metabolic activation. The test material was considered to be non-mutagenic under the conditions of this test.

Justification for classification or non-classification

Based on the results of the study available, the test item was not classified and labelled according to Regulation 1272/2008 (CLP), as amended for the eighteenth time in Regulation (EU) 2022/692.