1-(2,6-dimethylphenoxy)acetone

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:

2000

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5265 (The Salmonella typhimurium Bacterial Reverse Mutation Test)

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: EU Method B.14

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

1-(2,6-dimethylphenoxy)acetone

EC Number:

258-292-2

EC Name:

1-(2,6-dimethylphenoxy)acetone

Cas Number:

53012-41-2

Molecular formula:

C11H14O2

IUPAC Name:

1-(2,6-dimethylphenoxy)propan-2-one

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): 2,6-DMPA
- Physical state: liquid
- Analytical purity: 98.8 %
- Purity test date: May 20, 1999
- Lot/batch No.: 34
- Storage condition of test material: room temperature

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 98

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 100

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Test concentrations with justification for top dose:

31.6, 100.0, 316.2, 1000.0, 2500.0 and 5000.0 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: DMSO was compatible with the survival of the bacteria and the S9 activation.

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

other: 4-nitro-o-phenylene-diamine ; 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation); preincubation

DURATION
- Preincubation period: 60 min
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: 3 per concentration

Evaluation criteria:

A test item is considered as mutagenic if : - a dose-related increase in the number of revertant occurs and/or
- a reproducible biologically relevant positive response for at least one of the test points occurs
in at least one strain with or without metabolic activation.
A biologically relevant increase is described as follows : - if in strain TA 100 the numbers of reversions is at least twice as high
- if in strain TA 98 the number of reversions is at least three times higher
as compared to the spontaneous rate.

Statistics:

The Mutation Factor is calculated by dividing the mean value of the revertant counts through the mean values of the solvent control.

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

In conclusion it can be stated that during the described mutagenicity test and under the experimental conditions reported, the test item did not
cause gene mutations by base pair changes or frameshifts in the genome of the tester strains used.
Therefore, 2,6-DMPA is considered to be non-mutagenic in this bacterial reverse mutation assay

Executive summary:

In order to investigate the potential of 2,6 -Dimethylphenoxyaceton for its ability to induce gene mutations the plate incorporation test

( experiment I ) and the pre-incubation test ( experiment II ) were performed with the Salmonella typhimurium strains TA 98 and

TA 100 .

The test item was tested in two independent experiments at several concentrations. Each assay was conducted with and without metabolic activation ( S9 mix). The concentrations, including the controls, were tested in triplicate.The following concentrations of the test item were prepared and used in the experiments : 31.6, 100.0, 316.2, 1000.0, 2500 and 5000 µg/plate

Toxic effects of the test item were observed in both experiments at the upper concentrations both strains used with and without metabolic activation.

No substantial increase in revertant colony numbers of any of the two tester strains were detected at any concentration level of the test item either with or without metabolic activation in both independently performed experiments.

As positive controls reference mutagens were tested in parallel to the test item. They showed a distinct increase of induced revertant colonies.

The reported data of this mutagenicity test show that the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.

Therefore, 2,6 -DMPA is considered to be non-mutagenic in this bacterial reverse mutation assay.