Amides, C8-18 (even numbered) and C18-unsatd., N,N-bis(hydroxyethyl)

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not available

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Materials and methods

Principles of method if other than guideline:

The genotoxic potential of the test substance was determined by the induction of chromosomal aberrations in Chinese Hamster Ovary Cells both with and without metabolic activation.

GLP compliance:

no

Type of assay:

in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

Amides, C8-18 (even numbered) and C18-unsatd., N,N-bis(hydroxyethyl)

EC Number:

931-329-6

Cas Number:

68155-07-7

Molecular formula:

The alkyl chain length of the amide ranges between 8 and 18 carbon atoms

IUPAC Name:

Amides, C8-18 (even numbered) and C18-unsatd., N,N-bis(hydroxyethyl)

Test material form:

liquid: viscous

Method

Species / strain

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Details on mammalian cell type (if applicable):

No data

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254-induced male Sprague-Dawley rat liver S9 and cofactor mix

Test concentrations with justification for top dose:

16, 30, 50 µg/mL (-/+ S9)

Vehicle / solvent:

Ethanol

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

(Ethanol)

True negative controls:

no

Positive controls:

yes

Positive control substance:

mitomycin C

Remarks:

-S9: 0.0625 and 0.25 µg/mL

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

(Ethanol)

True negative controls:

no

Positive controls:

yes

Positive control substance:

cyclophosphamide

Remarks:

+S9: 2.5 and 7.5 µg/mL

Details on test system and experimental conditions:

Detailed protocol of this study has been presented by (Galloway et al (1987)).

DURATION
- Exposure duration: In the test without S9, cells were incubated in McCoy’s 5A medium with coconut oil acid diethanolamine condensate for 10 h; Colcemid was added and incubation continued for 2 h. The cells were then harvested by mitotic shake-off, fixed, and stained with Giemsa. For the test with S9, cells were treated with coconut oil acid diethanolamine condensate and S9 for 2 h, after which the treatment medium was removed and the cells were incubated for 11 h in fresh medium, with Colcemid present for the final 2 h. Cells were harvested in the same manner as for the treatment without S9.
- Harvest time: 12 h (without S9); 13 h (with S9)

NUMBER OF REPLICATIONS: A single flask per dose was used, and tests yielding equivocal or positive results were repeated.
NUMBER OF CELLS EVALUATED: Two hundred first-division metaphase cells were scored at each dose level.

Evaluation criteria:

Cells were selected for scoring on the basis of good morphology and completeness of karyotype (21 ± 2 chromosomes). All slides were scored blind and those from a single test were read by the same person. Classes of aberrations included simple (breaks and terminal deletions), complex (rearrangements and translocations), and other (pulverised cells, despiralised chromosomes, and cells containing 10 or more aberrations).

Statistical analyses were conducted on both the dose response curve and individual dose points. For a single trial, a statistically significant (P ≤0.05) difference for one dose point and a significant trend (P ≤0.015) were considered weak evidence for a positive response; significant differences for two or more doses indicates the trial was positive. A positive trend test in the absence of a statistically significant increase at any one dose resulted in an equivocal call. Ultimately, the trial calls were based on a consideration of the statistical analyses as well as the biological information available to the reviewers.

Statistics:

Significance of percent cells with aberrations tested by the linear regression trend test versus log of the dose.

Results and discussion

Test results

Key result

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Any other information on results incl. tables

For detailed results table kindly refer to the attached background materials section of the IUCLID.

Applicant's summary and conclusion

Conclusions:

Under the study conditions, the test substance was found to be non-mutagenic.

Executive summary:

A study was conducted to evaluate the in vitro genetic toxicity of the test substance, C8-18 and C18-unsatd. DEA, in a chromosomal aberrations assay using Chinese Hamster Ovary (CHO) cells. The concentrations tested were 16, 30 and 50 µg/mL with and without metabolic activation. Concurrent solvent and positive controls (mitomycin-C (without S9) and cyclophosphamide (with S9)) were also included. Cells were selected for scoring on the basis of good morphology and completeness of karyotype (21 ± 2 chromosomes). All slides were scored blind and those from a single test were read by the same person. Two hundred first-division metaphase cells were scored at each dose level. Chromosomal aberration data were presented as percentage of cells with aberrations. Significance of percent cells with aberrations tested by the linear regression trend test versus log of the dose. The test substance did not induce an increase in the number of chromosomal aberrations in cultured Chinese hamster ovary cells after incubation, with or without S9. Under the study conditions, the test substance was found to be non-mutagenic (Irwin, 2001).