2-methylpropyl-(R)-2-hydroxypropanoate

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD Guideline Study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Remarks:

Centre International de Toxicologie, France

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-methylpropyl-(R)-2-hydroxypropanoate

EC Number:

407-770-0

EC Name:

2-methylpropyl-(R)-2-hydroxypropanoate

Cas Number:

61597-96-4

Molecular formula:

C7 H14 O3

IUPAC Name:

2-methylpropyl-(R)-2-hydroxypropanoate

Details on test material:

- Name of test material (as cited in study report): D-(+)-Isobutyllactat
- Physical state: liquid
- Analytical purity: 99.5%
- Isomers composition: D/(D+L) = 99.4%
- Lot/batch No.: PR 596
- Storage condition of test material: 4°C

Method

Target gene:

his

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Metabolic activation:

with and without

Metabolic activation system:

Aroclor induced rat liver S9-mix

Test concentrations with justification for top dose:

0, 100, 500, 1000, 2500, 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

without S9-mix for TA100 and TA1535

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

without S9-mix for 1537

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

without S9-mix for TA98 and TA1535

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-anthramine

Remarks:

with S9-mix for all used strains

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 to 72 hours
- Expression time (cells in growth medium): up to 72 hours


DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Evaluation criteria:

- a test substance is considered as mutagenic it, for each test, it induces a doubling in the number of revertants when compared to that in the negative and/or solvent controls, for at least one of the tested strains and at one or more of the tested concentrations. In this case, a statistically significant dose relationship is investigated, using a linear regression analysis, and considered as signiticant if p ≤ 0.05 (for n = 18 values, the correlation coefficient r must be ≥ 0.47).
- a test substance is considered as non-mutagenic if the above two criteria are not fully met.

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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

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'.

Any other information on results incl. tables

The number of revertants obtained in the presence of the test substance with and without S9 mix for the 5 strains was equivalent to that of the negative and/or solvent controls. During the second assay, a doubling of the number of revertants when compared to that of the solvent was obtained at 2500 µg/plate concerning the TA 1537 strain. No statistically significant dose-effect relationship was observed (Y = 9.8 x + 11 r = 0.40) and this result was not noted in the first assay. Consequently, it was considered as non-significant.