2-{2-[(2-ethylhexyl)oxy]ethoxy}ethyl prop-2-enoate

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

Study period:

The study was conducted between 30 July 2015 and 20 August 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: 1= Reliable without restriction o GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-{2-[(2-ethylhexyl)oxy]ethoxy}ethyl prop-2-enoate

Cas Number:

117646-83-0

Molecular formula:

C15H28O4

IUPAC Name:

2-{2-[(2-ethylhexyl)oxy]ethoxy}ethyl prop-2-enoate

Test material form:

other: liquid

Details on test material:

Identification:
M120

Batch:
NC-5635-01

Purity:
99.4%

Physical state/Appearance:
Clear colourless liquid

Expiry Date:
05 October 2015

Storage Conditions:
Room temperature in the dark

Method

Target gene:

see below

Species / strain

Species / strain 1

Species / strain / cell type:

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

Details on mammalian cell type (if applicable):

Strains Genotype Type of mutations indicated
TA1537 his C 3076; rfa-; uvrB-: frame shift mutations
TA98 his D 3052; rfa-; uvrB-;R-factor
TA1535 his G 46; rfa-; uvrB-: base-pair substitutions
TA100 his G 46; rfa-; uvrB-;R-factor

Additional strain / cell type characteristics:

other: see above

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Details on mammalian cell type (if applicable):

Strain Genotype Type of mutations indicated
WP2uvrA trp-; uvrA-: base-pair substitution

Additional strain / cell type characteristics:

other: see above

Metabolic activation:

with and without

Metabolic activation system:

S9

Test concentrations with justification for top dose:

1.5, 5, 15, 50, 150, 500, 1500 and 5000 µg/plate

Vehicle / solvent:

dimethyl sulphoxide

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

N-ethyl-N-nitro-N-nitrosoguanidine

benzo(a)pyrene

other: 2-Aminoanthracene (2AA)

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:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Prior to use, the master strains were checked for characteristics, viability and spontaneous reversion rate (all were found to be satisfactory). The amino acid supplemented top agar and the S9-mix used in both experiments was shown to be sterile. The test item formulation was also shown to be sterile. These data are not given in the report.

Results for the negative controls (spontaneous mutation rates) were considered to be acceptable. These data are for concurrent untreated control plates performed on the same day as the Mutation Test.

The maximum dose level of the test item in the first experiment was selected as the maximum recommended dose level of 5000 µg/plate. There was a visible reduction in the growth of the bacterial background lawn and/or substantial reductions in revertant colony frequency noted at 5000 µg/plate toSalmonellastrains TA1535 (presence of S9-mix) and TA1537 (absence of S9‑mix), in the first mutation test. No toxicity was noted to any of the remaining strains at any test item dose level in either the presence or absence of S9-mix. Consequently, the maximum recommended dose level was employed as the maximum dose in the second mutation test. In the second mutation test (pre-incubation method), the test item induced a stronger toxic response with weakened bacterial background lawns noted in the absence of S9-mix from 500 µg/plate (TA1537), 1500 µg/plate (TA1535) and at 5000 µg/plate (TA100). In the presence S9-mix weakened bacterial background lawns were noted from 500 µg/plate (TA1535 and TA1537). No toxicity was noted to any of the remaining strains at any test item dose level in either the presence or absence of S9-mix. The sensitivity of the bacterial tester strains to the toxicity of the test item varied slightly between strain type, exposures with or without S9-mix and experimental methodology. No test item precipitate was observed on the plates at any of the doses tested in either the presence or absence of S9-mix.

There were no toxicologically significant increases in the frequency of revertant colonies recorded for any of the bacterial strains, with any dose of the test item, either with or without metabolic activation (S9-mix) in Experiment 1 (plate incorporation method). Similarly, no toxicologically significant increases in the frequency of revertant colonies were recorded for any of the bacterial strains, with any dose of the test item, either with or without metabolic activation (S9-mix) in Experiment 2 (pre‑incubation method). Small, statistically significant increases in TA1535 revertant colony frequency were observed in the first mutation test at 5000 µg/plate (presence of S9-mix only) and the second mutation test from 1500 µg/plate (absence of S9-mix) and 500 µg/plate (presence of S9-mix). These increases were considered to have no biological relevance because weakened bacterial background lawns were also noted alongside the dose concentrations. The false response, therefore, is considered to be due to additional histidine being available to His^-bacteria allowing these cells to undergo several additional cell divisions and presenting as non-revertant colonies.

 

All of the positive control chemicals used in the test induced marked increases in the frequency of revertant colonies thus confirming the activity of the S9-mix and the sensitivity of the bacterial strains.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

M120 was considered to be non-mutagenic under the conditions of this test.