Hydrocarbons, C4

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented publication meeting basic scientific principles.

Data source

Reference

Reference Type:

publication

Title:

Improved method for mutagenicity testing of gaseous compounds by using a gas sampling bag.

Author:

Araki, A. et al.

Year:

1994

Bibliographic source:

Mutat Res. 307; 335-344.

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

results only shown as graphical, not tabulated form, no data on cytotoxicity, no positive controls performed

Principles of method if other than guideline:

1,3-butadiene was tested by an improved method for mutagenicity testing of gaseous compounds by using a gas sampling bag.

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Buta-1,3-diene

EC Number:

203-450-8

EC Name:

Buta-1,3-diene

Cas Number:

106-99-0

Molecular formula:

C4H6

IUPAC Name:

buta-1,3-diene

Details on test material:

- Name of test material (as cited in study report): 1,3-Butadiene
- Analytical purity: no data
- Physical state: gas
- Source: Tokyo Kasei Co. Ltd., Tokyo (Japan).

Method

Target gene:

Genes involved in Histidine-synthesis

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:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Phenobarbital and 5,6-benzoflavone induced rat liver S9

Test concentrations with justification for top dose:

0, 10, 20 and 50 %

Vehicle / solvent:

Air

Details on test system and experimental conditions:

- Exposure duration: 48 h
Bacterial plates were made by the agar overlay method, the amount of top agar was 2 ml per plate, the amount of S9 was 100 µl per plate, the exposure temperature was 37°C, the exposure period was 48 h and the exposure volume of gas was 500 ml per plate.

Statistics:

No statistics performed

Results and discussion

Test results

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

not specified

Additional information on results:

1,3-Butadiene is clearly mutagenic to TA1535 with metabolic activation at a concentration of more than 3% and shows a dose-related marginal
increase of revertant colonies on TA100 with S9 mix.

Any other information on results incl. tables

The results were not given in tabulated form.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
positive with metabolic activation

1,3-Butadiene is mutagenic in bacteria.

Executive summary:

Araki et al., 1994 developed a simple and safety gas exposure method for mutagenicity testing of gases.

1,3 -butadiene was tested at 0, 10, 20 and 50 % in air in different S. typhimurium strains (TA98, TA100, TA1535 and TA1537) and in E. coli WP2 uvrA, both with and without the addition of a rat liver homogenate metabolising system. Data on cytotoxicity were not shown.

1,3 -Butadiene was clearly mutagenic to TA1535 with metabolic activation at a concentration of more than 3% and showed a dose-related marginal increase of revertant colonies on TA100 with S9 mix.