Isononyl alcohol

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:

8 July 1986 to 19 July 1986

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study conducted to EWG 84/449/B.14. The study is comparable to current guideline study (EU Method B.14) with acceptable restrictions. A declaration by the original Study Director that the translation is accurate, although the study is not GLP compliant.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Deviations:

no

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Isononyl alcohol

EC Number:

248-471-3

EC Name:

Isononyl alcohol

Cas Number:

27458-94-2

Molecular formula:

C9H20O

IUPAC Name:

3,5,5-trimethylhexan-1-ol

Details on test material:

- Name of test material (as cited in study report): Isononanol
- Substance type: Technical material
- Physical state: Colourless liquid
- Stability under test conditions: No data
- Storage condition of test material: No data

Method

Target gene:

Histidine operon

Species / strain

Species / strain 1

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not specified

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

S9

Test concentrations with justification for top dose:

0 (water contol), 0 (vehicle control), 10, 50, 250, 1000 and 5000 µg Isononanol /plate with and without S9 metabolic activation. Test concentrations were half log intervals.

Vehicle / solvent:

Dimethylsulphoxide (DMSO)
A stock solution was prepared on the day of testing by dissolving isononanol in DSMO. All subsequent dilutions were made in the same solvent

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

DMSO with all strains

True negative controls:

no

Positive controls:

yes

Remarks:

With TA 100 strain and S9 mix only

Positive control substance:

cyclophosphamide

Details on test system and experimental conditions:

Plate incorporation test

0.1 ml of the solvent DMSO, 0.5 ml phosphate buffer or 0.5 ml S9 mix for metabolic activation, 2 ml of molten, trace histidine supplemented, top agar at 45ºC, and 0.1ml of the bacterial culture were mixed in sterile tubes. Mixing was done in triplicate for each bacterial strain and for each concentration of the test material. The mixture was then poured onto the surface of minimal agar plates . These plates were incubated at 37 degrees centigrade for 96 hours and then the number of revertant colonies counted.

Preincubation test

0.1ml of each bacterial culture was mixed with 0.5ml phosphate buffer or 0.5ml S9 mix for metabolic activation,. Then 50ul of cyclophosphamide, DMSO or test substance in DSMO were added and the tubes incubated at 30 degree celcius for 30 minutes with gentle agitation. At the end of the incubation period, 2ml of molten top agar was added to each tube and mixed briefly and poured onto minimal agar plates. These plates were incubated at 37 degrees centigrade for 96 hrs and then the number of revertant colonies were counted.

Three replicates for each treatment level.

Evaluation criteria:

For a test compound to be considered positive, it must (in two independent experiments),cause at least a doubling in the mean revertants per plate of at least one tester strain. This increase must be accompanied by a dose response towards increasing concentrations of the test article. A test article
that does not meet these criteria will be called non-mutagenic in bacteria. Single increases in revertant frequencies, which are not dose-related and
not reproducible in two independent tests are considered non-relevant. If however these increases do occur in both tests, this will be taken as an
indication of a mutagenic effect.

Statistics:

Not used

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:

S. typhimurium, other: TA 1538

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:

not applicable

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: No data
- Effects of osmolality: No data
- Evaporation from medium: No data
- Water solubility: No data
- Precipitation: No data
- Other confounding effects: No data

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

In the plate incorporation assay as well as the preincubation assay, treatment with isononanol did not result in a dose-related significant increase in the revertant frequency of any of the five tester strains TA98, TA100, TA 535, TA1537 or TA1538.

The tables of results showing revertant colonies for each tester strain with and without S9 are included in the attached document:

Tables (Ames Test) from Report.pdf

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Isononanol did not induce a mutagenic effect in S typhimurium in two independent tests. It is not therefore considered to be a bacterial mutagen

Executive summary:

A study was performed at the Laboratories of Infracor GmbH, on behalf of Hüls Aktiengesellschaft Germany, to investigate the ability of the test substance Isononanol to induce reverse mutations in an in vitro bacterial system. Salmonella typhimurium strains TA 98, TA 100, TA 1535, TA 1537 and TA 1538 were treated with Isononanol by the Ames test plate incorporation method as well as the pre-incubation method. Dose levels covered the range of 10 to 5000 µg/plate, in triplicate both with and without the addition of metabolising system (S9 mix), were employed using Study design reference EWG Directive 84/449 B.14. A reproducible mutagenic activity of the test substance to any of the tester strain was not observed with or without metabolic activation. Isononanol is therefore considered not to be a bacterial mutagen. This Ames Test study is considered to be 'reliable with restriction' and satisfies the guideline requirements of the bacterial reverse mutation assay.