tert-butyl acrylate

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

01 Aug 2001 - 29 Nov 2001 (experimental)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

tert-butyl acrylate

EC Number:

216-768-7

EC Name:

tert-butyl acrylate

Cas Number:

1663-39-4

Molecular formula:

C7H12O2

IUPAC Name:

tert-butyl acrylate

Specific details on test material used for the study:

- Name of test material (as cited in study report): Tert.-Butylacrylat
- Physical state: colorless liquid
- Analytical purity: 99.6%
- Purity test date: 2001-07-16
- Lot/batch No.: Tank B 601
- Stability under test conditions: verified by reanalysis
- Storage condition of test material: Refrigerator, protected from light

Method

Target gene:

his- (S. typhimurium), trp- (E. coli)

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:

Aroclor 1254 induced rat liver S-9 mix

Test concentrations with justification for top dose:

20, 100, 500, 2500 and 5000 µg/plate both, in the standard plate test (SPT) and in the preincubation test (PIT)

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

yes

Remarks:

sterility control

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

other: N-methyl-N'-nitro-N-nitrosoguanidine (4-MNNG), 4-nitrophenylenediamine (4-NPD), 2-aminoanthracene (2-AA)

Details on test system and experimental conditions:

STANDARD PLATE TEST
Test tubes containing 2 ml soft agar kept in a water bath at 45°C, and remaining components added in the following order:
0.1 mL test solution or vehicle
0.1 mL bacterial suspension
0.5 mL S-9 mix (in tests with metabolic activation) or 0.5 mL phosphate buffer (in tests without metabolic activation).
After mixing, the samples are poured onto Vogel-Bonner agar plates (S. typhimurium) or minimal agar plates (E.coli)

PREINCUBATION TEST
0.1 mL test solution or vehicle, 0.1 mL bacterial suspension and 0.5 mL S-9 mix are incubated at 37°C for the duration of 20 minutes. Subsequently, 2 mL of soft agar is added and, after mixing, the samples are poured onto the agar plates.

BOTH TESTS
In each experiment 3 test plates per dose or per control used; after incubation at 37°C for 48 hours in the dark, the bacterial colonies ( his+/trp+ revertants) are counted. The titer was determined and in regularly measurements the strain characteristics were checked. Sterility control was performed.

Evaluation criteria:

POSITIVE RESULTS
- A dose-related and reproducible increase in the number of revertant colonies, i.e. about doubling of the spontaneous mutation rate in at least one tester strain either without S-9 mix or after adding a metabolizing system.
- A test substance is generally considered nonmutagenic in this test if: the number of revertants for all tester strains were within the historical negative control range under all experimental conditions in two experiments carried out independently of each other.

ACCEPTANCE CRITERIA
- The number of revertant colonies in the negative controls was within the normal range of the historical control data for each tester strain.
- The sterility controls revealed no indication of bacterial contamination.
- The positive control articles both with and without S-9 mix induced a significant increase in the number of revertant colonies within the range of the historical control data.
- The titer of viable bacteria was >= E+08/mL

Results and discussion

Test results

Test results 1

Key result

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:

cytotoxicity

Remarks:

A slight decrease in the number of revertants was occasionally observed in the standard plate test. In the preincubation test bacteriotoxicity was found from about 500 µg/plate onward.

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

A slight decrease in the number of revertants was occasionally observed in the standard plate test. In the preincubation test bacteriotoxicity was found from about 500 µg/plate onward.

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

No test substance precipitation was found.

Any other information on results incl. tables

Genotoxicity

Standard plate test (20 - 5000 µg/plate)
Strain	Metabolic activation system	Replicates	maximum revertant factor*	dose dependency	Assessment
TA 98	no	3	0.9	no	negative
	yes	3	0.7	no	negative
TA 100	no	3	1.0	no	negative
	yes	3	1.0	no	negative
TA 1535	no	3	0.9	no	negative
	yes	3	1.0	no	negative
TA 1537	no	3	1.0	no	negative
	yes	3	1.0	no	negative
WP2 uvr A	no	3	1.0	no	negative
	yes	3	0.8	no	negative
Preincubation test (20 - 5000 µg/plate)
Strain	Metabolic activation system	Replicates	maximum revertant factor*	dose dependency	Assessment
TA 98	no	3	0.9	no	negative
	yes	3	0.9	no	negative
TA 100	no	3	1.0	no	negative
	yes	3	0.9	no	negative
TA 1535	no	3	1.0	no	negative
	yes	3	1.0	no	negative
TA 1537	no	3	1.0	no	negative
	yes	3	0.9	no	negative
WP2 uvr A	no	3	1.0	no	negative
	yes	3	1.3	no	negative

* in non-toxic doses