2,6-xylidine

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1987

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosomal Aberration Test)

Principles of method if other than guideline:

A chromosome aberration test was performed with CHO cells for 108 test chemicals.

GLP compliance:

no

Type of assay:

in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

2,6-xylidine

EC Number:

201-758-7

EC Name:

2,6-xylidine

Cas Number:

87-62-7

Molecular formula:

C8H11N

IUPAC Name:

2,6-dimethylaniline

Test material form:

liquid

Specific details on test material used for the study:

- Name of test material (as cited in study report): 2,6-xylidine
- no further data

Method

Species / strain

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Remarks:

WB1

Metabolic activation:

with and without

Metabolic activation system:

rat liver S9 fraction (Aroclor induced)

Test concentrations with justification for top dose:

900-1400 µg/ml

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

triethylenemelamine

cyclophosphamide

mitomycin C

Evaluation criteria:

For chromosome aberrations, linear regression analysis of the a single percentage of cells with aberrations vs the log-dose was used as the test for trend. To examine absolute increases over control levels at each dose, a binomial sampling assumption (as opposed to Poisson) was used, and the test was that described by Margolin et al [1983, pp 714-715].The P values were adjusted by Dunnett's method to take into account the multiple dose comparisons . For data analysis, we used the "total" aberration category, and the criterion for a positive response was that the adjusted P value be <0.05.

Results and discussion

Test results

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

The aberration tests with and without S9 were positive rather at toxic doses and in the presence of precipitate.
Cytotoxic effects at 900 µg/ml, precipitates; significant at 1000 µg/ml (- S9) or 1200 µg/ml (+ S9).