Hydrocarbons, C4, 1,3-butadiene-free, polymd., dibutylene fraction

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other: GLP compliant, guideline study, available as unpublished report, no restrictions, fully adequate for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

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:

OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)

Test guideline 3

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2,4,4-trimethyl pentene

IUPAC Name:

2,4,4-trimethyl pentene

Constituent 2

Reference substance name:

2,2,4-trimethylpentane

EC Number:

208-759-1

EC Name:

2,2,4-trimethylpentane

Cas Number:

540-84-1

Molecular formula:

C8H18

IUPAC Name:

2,2,4-trimethylpentane

Constituent 3

Reference substance name:

Reference substance 003

Cas Number:

25167-70-8

Molecular formula:

C8H16

Details on test material:

- Name of test material (as cited in study report): 2,4,4-trimethyl pentene (also known as diisobutylene and diisobutene).
- Physical state: clear, colourless liquid.
- Analytical purity: Batch R11 95.19%, Batch 155833 no information
- Lot/batch No.: Batch No 2 (a 50:50 mixture of two original batches of 2,4,4-trimethyl pentene - the details of which are as follows: Batch No. R11 supplied by Shell and Batch No. 155833 supplied by Erdolchemie.
- Expiration date of the lot/batch: 29 April 1997
- Storage condition of test material: Under nitrogen, protected from light in a cool store

Method

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:

Arochlor-induced rat liver S9

Test concentrations with justification for top dose:

Range finding test: 5, 15, 50, 150, 500, 1500 µg 2,4,4 trimethyl pentene
Main test with pre-incubation: 50, 150, 500 and 1500 µg 2,4,4 trimethyl pentene

Vehicle / solvent:

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

Controls

Controls 1

Negative solvent / vehicle controls:

yes

Remarks:

ethanol

Controls 2

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

as a solution in DMSO for TA1535 +S9 and WP2uvrA +S9

Controls 3

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

as a solution in DMSO for TA1537 -S9

Controls 4

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

as a solution in DMSO for TA98 +S9

Controls 5

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

Remarks:

as a solution in DMSO for TA1537 +S9, TA100 +S9 and TA98 +S9

Controls 6

Positive controls:

yes

Positive control substance:

N-ethyl-N-nitro-N-nitrosoguanidine

Remarks:

as a solution in DMSO for TA1535 +S9, TA100 +S9, WP2uvrA +S9

Details on test system and experimental conditions:

METHOD OF APPLICATION: preincubation

DURATION
- Preincubation period: 20 mins at 37°C
- Exposure duration: 2 days at 37°C

NUMBER OF REPLICATIONS: 3

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Evaluation criteria:

For each replicate plating, the mean and standard deviation of the number of revertants per plate were calculated. For the test article to be evaluated positive, it must cause a dose-related increase in the mean revertants per plate of at least one tester strain over a minimum of two increasing concentrations of test article.

Statistics:

The mean and standard deviation of the number of revertants per plate were calculated. No statistical analyses.

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:

not specified

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with metabolic activation
negative without metabolic activation

2,4,4-trimethyl pentene did not exhibit any mutagenic activity under the conditions of test.

Executive summary:

The mutagenic potential of 2,4,4 -trimethylpentene was assessed in a bacterial reverse mutation assay (the Ames test) with and witout metabolic activation. 2,4,4-trimethyl pentene, did not exhibit any mutagenic activity under the conditions of test.