(chloromethyl)vinylbenzene

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1976

Report date:

1976

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

neither TA102 nor a strain of E.coli included

Principles of method if other than guideline:

The substance was examined for mutagenic effects in five strains of Salmonella typhimurium (TA1535, TA1537, TA1538, TA98, TA100).

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

(chloromethyl)vinylbenzene

EC Number:

250-005-9

EC Name:

(chloromethyl)vinylbenzene

Cas Number:

30030-25-2

Molecular formula:

C9H9Cl

IUPAC Name:

1-(chloromethyl)-3-ethenylbenzene; 1-(chloromethyl)-4-ethenylbenzene

Test material form:

liquid

Details on test material:

Lot #06174

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:

S. typhimurium TA 1538

Metabolic activation:

with and without

Metabolic activation system:

polychlorinated biphenyl-stimulated mouse liver homogenate

Test concentrations with justification for top dose:

0.1-500 µg per plate

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

identical to negative controls

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: 4-o-tolylazo-o-toluidine; N-methyl-N'-nitro-N-nitrosoguanidine

Details on test system and experimental conditions:

The S. typhimurium strains used in this study were obtained from Dr. Bruce Ames of the University of California at Berkeley.
For each experiment, an inoculum from frozen stock cultures was grown overnight at 37 °C in a nutrient broth consisting of 1% tryptone and 0.5% yeast
extract. After stationary overnight growth, the cultures were shaken for 3 to 4 hours to ensure optimal growth. Each culture was checked for sensitivity to crystal violet. The presence of the rfa- mutation makes the indicator strain sensitive to this dye, whereas the parent strain, rfa+, is not sensitive to the dye. However, the mutation is reversible, leading to the accumulation of rfa+ cells in the culture.Therefore, the cells must be tested routinely to ensure their sensitivity to crystal violet . Each culture was also tested by specific mutagens known to revert each test strain (positive controls).

To a sterile 13 x 100 mm test tube placed in a 43 °C heating block, the following solutions were added consecutively:
(1) 2 mL of 0.6% agar containing 0.05 mM histidine and 0.05 mM biotin
(2) 0.1 mL of indicator organisms
(3) 0.5 mL of metabolic activation mixture (optional)
(4) Up t o 100 mL of a solution of the test chemical.
For negative controls, steps (1), (2), and ( 3 ) (optional) and 100 mL of the solvent for the test chemical wwere used.
The mixture was stirred gently and then poured onto minimal agar plates. After setting of the soft agar, the plates were incubated at 37 °C for 2 days.

Evaluation criteria:

The number of his+ revertants (colonies that grew on plates lacking a sufficient amount of histidine to support colony formation) were counted and recorded. Some of the revertants were routinely tested to confirm that they were his+, required biotin, and were sensitive to crystal violet (rfa-).

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 500 µL per plate

Vehicle controls validity:

valid

Remarks:

vehicle not specified

Untreated negative controls validity:

valid

Remarks:

identical to vehicle control

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 500 µL per plate

Vehicle controls validity:

valid

Remarks:

vehicle not specified

Untreated negative controls validity:

valid

Remarks:

identical to vehicle control

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Remarks:

vehicle not specified

Untreated negative controls validity:

valid

Remarks:

identical to vehicle control

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 500 µL per plate

Vehicle controls validity:

valid

Remarks:

vehicle not specified

Untreated negative controls validity:

valid

Remarks:

identical to vehicle control

Positive controls validity:

valid

Test results 5

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 500 µL per plate

Vehicle controls validity:

valid

Remarks:

vehicle not specified

Untreated negative controls validity:

valid

Remarks:

identical to vehicle control

Positive controls validity:

valid

Any other information on results incl. tables

Summary of results

Compound vinylbenzyl chloride

Test Strains:

Salmonella typhimurium TA98, TA100, TA1535, TA1537, TA1538

Activation system:

Aroclor 1254 (polychlorinated biphenyl) mouse liver

Bacterial test strains, non-activated	Bacterial test strains, activated
negative	negative

The test compound vinylbenzyl chloride was considered to be not mutagenic with five S. typhimurium strains, both in the presence and in the absence of a metabolic activation system. Vinylbenzyl chloride was tested at amounts between 0.1 and 100 µg per plate (500 µg per plate were toxic to all Salmonella strains except for TA1535).

Applicant's summary and conclusion

Conclusions:

The compound was considered to be not mutagenic with the S. typhimurium strains TA98,TA100, TA1535, TA1537, TA1538, both in the presence and in the absence of a metabolic activation system.

Executive summary:

Vinylbenzyl chloride was tested at concentrations varying between 0.1 and 100 µL per plate (500 µL per plate were toxic to all Salmonella strains except for TA1535). The compound was considered to be not mutagenic with five S. typhimurium strains (TA98,TA100, TA1535, TA1537, TA1538), both in the presence and in the absence of a metabolic activation system.