Nonanoic acid, 2-oxiranylmethyl ester, branched

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian germ cell study: gene mutation

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: The study was conducted according to the O.E.C.D. test guideline488 with GLP compliance including concentration and stability verification.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: O.E.C.D. test guideline 488, "Transgenic Rodent Somatic and Germ Cell Gene Mutation Assay".

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

transgenic rodent mutagenicity assay

Test material

Test material information

Constituent 1

Reference substance name:

2,3-epoxypropyl neodecanoate

EC Number:

247-979-2

EC Name:

2,3-epoxypropyl neodecanoate

Cas Number:

26761-45-5

Molecular formula:

C13H24O3

IUPAC Name:

Oxiran-2-ylmethyl 2-ethyl-2,5-dimethylhexanoate

Constituent 2

Reference substance name:

Neodecanoic acid, oxiranylmethyl ester

IUPAC Name:

Neodecanoic acid, oxiranylmethyl ester

Test material form:

other: Colorless liquid at room temperature.

Details on test material:

As per IUCLID5 Sections 1.1. 1.2. 1.4. and 4.1. for 2,3-epoxypropyl neodecanoate, REACH Registration: 01-2119431597-33-0000.

Test animals

Species:

mouse

Strain:

other: CD2-lacZ80/HazfBR

Sex:

male

Details on test animals or test system and environmental conditions:

young adult male Muta(TM)Mouse (CD2 lacZ80/HazfBR) mice were purchased from Harlan, UK. The mice were 8-13 weeks old and weighted 23-33 gm at Experimental Initiation. The animals were housed in groups of three in cages in a room air conditioned to provide 15-20 air changes/hour. The temperature and relative humidity ranges were 20 to 24C and 45 to 65%, respectively. Fluorescent lighting was controlled automatically to give a cycle of 12 hours light (0600 to 1800) and 12 hours dark. Throughout the study the animals had access ad libitum to SQC Rat and Mouse Maintenance Diet No 1, Expanded (Special Diets Services Ltd. Witham). Mains water was provided ad libitum via water bottles. Bedding was provided on a weekly basis to each cage by use of clean European softwood bedding (Datesand Ltd, Manchester). The animals were acclimatised for at least 5 days before being placed on study.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

Corn oil

Details on exposure:

All test test substance and vehicle treatments were given via oral gavage with test substance dose based on individual animal body weight,

Duration of treatment / exposure:

42 days.

Frequency of treatment:

Once per day.

Post exposure period:

Three days

Doses / concentrations

Remarks:

Doses / Concentrations:
250, 500 and 1000 mg/kg/of body weight
Basis:
nominal in diet

No. of animals per sex per dose:

Seven male animals

Control animals:

yes, concurrent vehicle

Positive control(s):

Ethylnitrosourea at 100 mg/kg of body weight by intraperitonel injection.

Examinations

Tissues and cell types examined:

Liver, Kidney, Bone marrow and Developing sperm cells from seminiferous tubules.

Details of tissue and slide preparation:

Liver and kidney tissues were rinsed in phosphate buffered saline (PBS) and flash frozen in liquid nitrogen. Frozen samples were moved to a freezer at < 50°C for long term storage. Spermatazoa were isolated from the cauda epididymis; developing sperm cells were isolated from the seminiferous tubules. For each animal the cauda epididymis and seminiferous tubules were incubated separately in PBS at approximately 37°C for approximately 1 hour after which the tissue was removed and the spermatazoa or developing sperm cell suspensions were stored frozen at < 50°C.
Bone marrow was removed from both femurs by cutting off each end to expose the bone marrow and repeatedly flushing with approximately 2 mL of PBS. These samples were briefly held at 2-8°C prior to isolation of the cells by centrifugation. The supernatant was removed and the cell pellets were stored frozen at < 50°C. DNA for gene-mutation analysis was extracted from these cells and tissues. No slides were prepared.

Evaluation criteria:

The test substance was considered positive, i.e. capable of inducing gene-mutation, if a statistically significant increase in theMutant Frequency (MF) occurred at one or more dose levels in at least one of the tissues examined. The test substance was considered negative in this assay if no statistically significant increase in MF occurred in any of the tissues examined. The biological relevance of any positive findings were considered in the context of the laboratory’s background control historical database.

Statistics:

Vehicle control and test substance groups were analysed using one-way analysis of variance (ANOVA). An overall dose response test was performed along with Dunnett’s test for pairwise comparisons of each treated group with the vehicle control. All tests were performed with a one-sided risk for increasing response. Levene’s test for equality of variances across the groups was also performed and in all cases showed no evidence of heterogeneity (P>0.01).

Results and discussion

Test results

Sex:

male

Genotoxicity:

positive

Toxicity:

not examined

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

The test substance induced a statistically significant, dose-related increase of the gene-mutation frequency in the liver, kidney and bone marrow of the MutaMouse over the dose range of 250 - 1000 mg/kg of body weight. Test substance treatment induced an increase of the mutant frequency in the liver of 3.1-fold the concurrent vehile control value at 1000 mg/kg. In the kidney the increase in mutant frequency was approximately 2.2-fold at 1000 mg/kg and in the bone marrow the increase in mutant frequency was 2.9-fold the vehicle control value at 1000 mg/kg of body weight.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): positive
The test substance is a gene-mutagen in vivo in the MutaMouse. Treatment with the test substance induced a statisticall significant, dose-related increase of the mutant frequency in the liver, kidney and bone marrow of the MutaMouse. No increase of the mutant frequency was observed in the developing and mature sperm. Therefore, the test substance, 2,3-epoxypropyl neodecanoate is a CLP Category 2 Mutagen, H341, "Suspected of causing genetic defects". This Classification and Labeling is considered to be appropriate for the subject of Registration, Neononanoic acid glycidyl ester.

Executive summary:

The structural analog test substance, 2,3-epoxypropyl neodecanoate was accessed for the potential to induce gene-mutation in the in vivo MutaMouse test system up to an oral dose level of 1000 mg/kg by an O.E.C.D. test guideline 488 study. The test substance is a gene-mutagen in vivo in the MutaMouse. Treatment wiht the test substance induced a statisticall significant, dose-related increase of the mutant frequency in the liver, kidney and bone marrow of the MutaMouse. No increase of the mutant frequency was observed in the developing and mature sperm. Therefore, the test substance, 2,3-epoxypropyl neodecanoate is a CLP Category 2 Mutagen, H341, "Suspected of causing genetic defects". This Classification and Labeling is considered to be appropriate for the subject of Registration, Neononanoic acid glycidyl ester.