Hexanamide, N-(2-hydroxyethyl)-3,5,5-trimethyl-

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

1997

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

N-(2-hydroxyethyl)-3,5,5-trimethylhexanamide

EC Number:

800-884-5

Cas Number:

1154308-86-7

Molecular formula:

C11 H23 N1 O2

IUPAC Name:

N-(2-hydroxyethyl)-3,5,5-trimethylhexanamide

Details on test material:

- Name of test material (as cited in study report): Additol® SXW 6246/90 Coating Additives
- Physical state: Amber Liquid
- Analytical purity: 94.67% (+5.33% water)
- Batch no.: 210129777
- Expiration date of Batch no. 210129777: 28 February 2013
- Storage condition of test material: Ambient, Dark
- Composition of test material, percentage of components: Amides, C8-12, N-(hydroxyethyl) 90622-90-5 (94.67%) and Water 7732-18-5 (5.33%)

Method

Species / strain

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254-induced rat liver S9 (10%)

Test concentrations with justification for top dose:

17, 50, 167, 500, 1667 and 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Solubility and acceptable solvent for use with Ames test.

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

N-ethyl-N-nitro-N-nitrosoguanidine

other: 2-Aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar plate. Both direct plate incorporation method and preincubation method used

DURATION
- Preincubation period: 20 mins
- Exposure duration: Total exposure 3 days

NUMBER OF REPLICATIONS: 3

DETERMINATION OF CYTOTOXICITY
- Method: Condition of background lawn.

Evaluation criteria:

S. typhimurium strains TA 1535, TA 1537, and TA 98 and for E. coli WP2uvrA, 2 fold increase over mean concurrent vehicle control value.
S. typhimurium strain TA 100, a 1.5 fold increase over mean concurrent control value.

Statistics:

No

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 5000 µg/mL

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 5000 µg/mL

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 5000 µg/mL

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 5000 µg/mL

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 5000 µg/mL

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: None
- Other confounding effects: None

RANGE-FINDING/SCREENING STUDIES: Yes

COMPARISON WITH HISTORICAL CONTROL DATA: Not required

ADDITIONAL INFORMATION ON CYTOTOXICITY: In the first test, conducted by the Direct Plate Incorporation Method, toxicity to the bacteria was observed as a thinning of the background lawn of microcolonies, +/- a reduction in revertant colony numbers. This observation was made at the highest concentration of 5000 µg per plate in all strains in the absence of S9 mix and in strains TA 1535, TA 1537 and TA 100 in the presence of S9 mix.

In the second test, conducted by the Pre-incubation Method, toxicity was observed in all the bacterial strains at the 2 highest concentrations of 1667 and 5000 µg per plate, in both the absence and the presence of S9 mix.

Remarks on result:

other: no mutagenic potential

Remarks:

all strains/cell types tested

Any other information on results incl. tables

Tables in attachment (background material).

Applicant's summary and conclusion

Conclusions:

Under the conditions of the study, the substance was determined to be non-mutagenic in the reverse mutation assay with and without metabolic activation

Executive summary:

An in vitro study was conducted to investigate the potential of test substance to induce gene mutations Salmonella typhimurium strains, according to OECD Guideline 471, in compliance with GLP. The test substance was tested for mutagenic activity in Salmonella typhimurium strains TA 1535, TA 1537, TA 98 and TA 100 and in Escherichia coli WP2uvrA. Two independent tests were conducted on agar plates in triplicate in the absence and presence of an Aroclor 1254 induced rat liver S9 preparation and the co-factors required for mixed-function oxidase activity (S9 mix). The first test was conducted by the Direct Plate Incorporation Method, while the second test was conducted by the Pre-incubation Method. The test substance was dissolved and diluted in dimethylsulphoxide and was dosed at concentrations ranging from 17 to 5000 µg per plate in both the absence and the presence of S9 mix. The highest concentration represented the maximum concentration recommended by the guideline. Concurrent positive controls demonstrated the sensitivity of the assay and the metabolising activity of the S9 mix. No evidence of mutagenic activity was obtained with any strain in either test. The highest concentrations of the test substance were toxic to the bacteria, especially in the second test based on Pre-incubation Method. No precipitation of the test substance was observed at any of the tested concentrations. Under the conditions of the study, the substance was determined to be non-mutagenic in the reverse mutation assay with and without metabolic activation (Riach, 2012).