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Diss Factsheets

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
28.02 - 07.08.2001
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study without detailed documentation
Remarks:
study performed according to GLP and OECD guidelines

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2001
Report date:
2001

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
α-acetyl-γ-butyrolactone
EC Number:
208-235-2
EC Name:
α-acetyl-γ-butyrolactone
Cas Number:
517-23-7
Molecular formula:
C6H8O3
IUPAC Name:
α-acetyl-γ-butyrolactone
Details on test material:
-

Method

Target gene:
TA97a: hisD6610, TA 98: hisD3052; TA 100 and TA 1535 hisG46, TA102: hisG428
Species / strain
Species / strain / cell type:
S. typhimurium, other: TA97a, TA98, TA100, TA102, TA 1535
Details on mammalian cell type (if applicable):
- Type and identity of media: Salmonella typhimurium LT2
- Properly maintained: yes
Additional strain / cell type characteristics:
other: rfa, delta-uvrB, pKM101
Metabolic activation:
with and without
Metabolic activation system:
S9
Test concentrations with justification for top dose:
main experiment: 5, 2.5, 1.25, 0.625, 0.1 mg/l
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: water
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
yes
Positive controls:
yes
Positive control substance:
benzo(a)pyrene
Remarks:
+ Sodiumazide ; 4-Nitro-1,2-phenylendiam
Details on test system and experimental conditions:
METHOD OF APPLICATION: plate incorporation assay; and a preincubation modification assay

Results and discussion

Test results
Species / strain:
S. typhimurium, other: TA97a, TA98, TA100, TA102, TA 1535
Metabolic activation:
with and without
Genotoxicity:
negative
Remarks:
-
Cytotoxicity / choice of top concentrations:
not determined
Remarks:
-
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
Interpretation of results: negative

Substance is not mutagenic
Executive summary:

A-Lactone was evaluated for mutagenic activity in the Ames test. A standard plate incorporation and a preincubation modification assay in absence and in presence of an exogenous metabolic activation system (S9) were performed. Five Salmonella typhimurium tester strains (TA1535, TA97, TA98, TA100, and TA102) were employed. The activity of the S9 -mix and the responsiveness of the tester strains were verified by including appropriate controls into each experiment. The substance was dissolved in water. Concentration ranges between 0.1 to 5 mg/plate were chosen for the main experiments.

No significant increase in the number of revertant colonies was apparent in all five tester strains (TA1535, TA97, TA98, TA100, and TA102) using both methods, after treatment with A-Lactone.

Based on these data A-Lactone can be considered as not mutagenic in the Ames test under the described experimental conditions.