Isovaleraldehyde

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:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Does not meet important criteria of today standard methods (only one concentration tested, only four strains of S. typhimurium used, positive control substances different from guideline, limited reporting)

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

: only one concentration tested, only four strains of S. typhimurium used, positive control substances different from guideline, limited reporting

Principles of method if other than guideline:

Pre-guideline investigation; mutagenicity tests according to Ames et al (Mutat Res 31 (1975) 347) were performed for 239 compounds found as major constituents in tobacco and tobacco smoke.

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Isovaleraldehyde

EC Number:

209-691-5

EC Name:

Isovaleraldehyde

Cas Number:

590-86-3

Molecular formula:

C5H10O

IUPAC Name:

3-methylbutanal

Details on test material:

- Name of test material (as cited in study report): 3-methylbutanal (purchased from commercial source)
- Analytical purity: > 97%; compounds with impurities >3% as determined by thin-layer or gas chromatography were purified by means of liquid chromatography, recrystallization or destillation.

Method

Target gene:

his¯

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

S9-mix from livers of Aroclor 1254 induced male Sprague-Dawley rats

Test concentrations with justification for top dose:

3 µmol/plate (258.4 µg/plate)

Vehicle / solvent:

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

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: with S-9 mix: 2-aminoanthracene, without S-9 mix: N-methyl-N'-nitro-N-nitrosoguanidine

Details on test system and experimental conditions:

BASIC METHOD: according to Ames 1975

METHOD OF APPLICATION: not specified

DURATION
- Preincubation period: not specified
- Exposure duration: not specified
- Expression time (cells in growth medium): not specified

NUMBER OF REPLICATIONS: 3

DETERMINATION OF CYTOTOXICITY
- Method, other: the viable cell count was determined in separate plating experiments

OTHER EXAMINATIONS:
- Other: the presence of rfa-mutation was checked by crystal violet inhibition and the presence of the plasmid pKM101 in strains TA98 and TA100 was checked by resistance to ampicillin for each experiment

Results and discussion

Test results

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:

not specified

Remarks:

If cytotoxicity was indicated in a test by the absence of a background lawn, the test was repeated with a lower concentration.

Vehicle controls validity:

not specified

Untreated negative controls validity:

not examined

Positive controls validity:

not specified

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Findings are only presented in a summarizing table. Detailed test results regarding individual strains and controls, listing revertant counts, are not reported.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

In a bacterial reverse gene mutation assay according to Ames using four S. typhimurium tester strains (TA 98, TA100, TA1535, TA1537) but only one test concentration (258 µg/plate), 3-methylbutanal (isovaleraldehyde) did not induce a mutagenic response either with or without metabolic activation.