β-bromostyrene

Genetic toxicity: in vitro

Administrative data

Endpoint:

genetic toxicity in vitro

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from J check

Data source

Reference

Reference Type:

review article or handbook

Title:

Gene mutation toxicity study of the test chemical

Author:

NITE

Year:

2017

Bibliographic source:

J-check

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Principles of method if other than guideline:

Gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

β-bromostyrene

EC Number:

203-131-3

EC Name:

β-bromostyrene

Cas Number:

103-64-0

Molecular formula:

C8H7Br

IUPAC Name:

β-bromostyrene

Details on test material:

- Name of test material: Isoamyl phenylacetate
- Molecular formula: C13H18O2
- Molecular weight: 183.05 g/mol
- Substance type: Organic
- Purity: 99.6%

Method

Target gene:

Histidine

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Details on mammalian cell type (if applicable):

Not applicable

Additional strain / cell type characteristics:

not specified

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Details on mammalian cell type (if applicable):

Not applicable

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

No data

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Test concentrations with justification for top dose:

All strains: 0, 1.22, 4.88, 19.5, 78.1, 313, 1250 or 5000 µg/plate

TA100:
Without S9: 0, 2.44, 4.88, 9.77, 19.5, 39.1, 78.1 µg/plate
With S9: 0, 9.77, 19.5, 39.1, 78.1, 156, 313 µg/plate

TA1535: With and without S9: 0, 2.44, 4.88, 9.77, 19.5, 39.1, 78.1 µg/plate

TA98: With and without S9: 0, 9.77, 19.5, 39.1, 78.1, 156, 313 µg/plate

TA1535: With and without S9: 0, 2.44, 4.88, 9.77, 19.5, 39.1, 78.1 µg/plate

E.coli WP2 uvrA: With and without S9: 0, 9.77, 19.5, 39.1, 78.1, 156, 313 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: The chemical was soluble in DMSO

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

sodium azide

other: 2- (2- Furyl)-3-(5-nitro-2-furyl)acrylamide (TA100, WP2uvrA, TA98, -S9), 2-Methoxy-6-chloro-9-[3-(2-chloroethyl)-aminopropylamino]acridine.2HCl (TA1537, -S9), 2-Aminoanthracene (TA1535, WP2uvrA, +S9), Benzo[a]pyrene (TA100, TA1537, TA98, +S9)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar

DURATION
- Preincubation period: No data
- Exposure duration: No data
- Expression time (cells in growth medium): No data
- Selection time (if incubation with a selection agent): No data
- Fixation time (start of exposure up to fixation or harvest of cells): No data

SELECTION AGENT (mutation assays): No data
SPINDLE INHIBITOR (cytogenetic assays): No data
STAIN (for cytogenetic assays): No data

NUMBER OF REPLICATIONS: Triplicate plates were used/dose level and the study was performed in triplicates

NUMBER OF CELLS EVALUATED: No data

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index; cloning efficiency; relative total growth; other: No data

OTHER EXAMINATIONS:
- Determination of polyploidy: No data
- Determination of endoreplication: No data
- Other: No data

OTHER: No data

Rationale for test conditions:

No data

Evaluation criteria:

The plates were observed for a dose dependent increase in the number of revertants/plate

Statistics:

No data

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium, other: TA100, TA1535, TA98, TA1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not specified

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

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Additional information on results:

No data

Remarks on result:

other: No mutagenic potential

Any other information on results incl. tables

Table 1:

Metabolic activation system	Dose (µg/plate)	TA100	TA1535	WP2uvrA	TA98	TA1537
Without S9	DMSO	98	11	18	27	10
	113	11	17	32	7
	4.88	119	1	15	26	7
	19.5	112	5	15	25	6
	78.1	109	7	15	23	8
	313	0	0	0	0	0
	1250	0	0	0	0	0
	5000	0	0	0	0	0
With S9	DMSO	166	16	21	53	12
	1.22	195	14	20	53	7
	4.88	914	17	20	49	8
	19.5	229	10	21	49	5
	78.1	302	14	27	61	9
	313	0	0	0	0	0
	1250	0	0	0	0	0
	5000	0	0	0	0	0
Positive control		AF-2	SAZ	AF-2	AF-2	ICR-191
		535	331	81	436	1550
Positive control		BAP	2AA	2AA	BAP	BAP
		835	299	1153	292	118

 

Table 2:

Metabolic activation system	Dose (µg/plate)	TA100	TA1535	WP2uvrA	TA98	TA1537
Without S9	DMSO	125±17.1	14±3.5	28±1.0	16±3.6	8±2.5
	2.44	119±15.5	7±4.0	NT	NT	7±1.0
	4.88	120±4.6	11±2.5	NT	NT	8±2.5
	9.77	125±2.3	10±5.1	26±6.8	18±2.9	5±1.5
	19.5	117±7.5	8±3.8	26±4.0	20±11.9	6±2.3
	39.1	121±2.1	12±5.1	25±6.0	17±4.0	5±0.6
	78.1	112±10.4	7±0.6	20±8.1	15±2.5	6±2.0
	156	NT	NT	0±0.0	0±0.0	NT
	313	NT	NT	0±0.0	0±0.0	NT

 

 

Table 3:

Metabolic activation system	Dose (µg/plate)	TA100	TA1535	WP2uvrA	TA98	TA1537
Without S9	DMSO	143±9.0	8±2.5	25±7.1	51±11.3	11±2.9
	2.44	NT	13±2.1	NT	NT	14±3.0
	4.88	NT	8±3.1	NT	NT	9±3.5
	9.77	151±5.3	15±2.6	28±13.1	57±8.2	9±3.2
	19.5	166±7.5	9±1.0	28±3.0	44±7.0	10±1.5
	39.1	188±12.9	18±4.2	30±4.5	47±5.7	17±4.0
	78.1	237±29.5	12±3.2	25±5.9	53±10.7	11±3.2
	156	127±10.5	NT	29±6.2	31±2.9	NT
	313	0 0.0	NT	0 0.0	0 0.0	NT

 

Table 4:

Metabolic activation system	Dose (µg/plate)	TA100	TA1535	WP2uvrA	TA98	TA1537
Without S9	DMSO	107±18.0	14±3.8	12±1.7	19±9.5	9±0.6
	2.44	121±5.1	15±1.5	NT	NT	6±1.5
	4.88	118±7.0	9±3.6	NT	NT	4±0.0
	9.77	121±9.9	10±2.3	14±5.2	19±1.7	5±2.5
	19.5	123±12.3	7±1.2	15±1.7	19±3.2	9±2.3
	39.1	112±13.5	8±3.6	21±5.5	19±3.5	5±1.0
	78.1	94±3.5	7±1.0	16±4.5	20±5.2	7±3.1
	156	NT	NT	12±4.6	0±0.0	NT
	313	NT	NT	0 0.0	0±0.0	NT

 

Table 5:

Metabolic activation system	Dose (µg/plate)	TA100	TA1535	WP2uvrA	TA98	TA1537
Without S9	DMSO	124±15.1	9±3.2	19±6.0	46±7.5	11±2.6
	2.44	NT	9±2.0	NT	NT	9±3.5
	4.88	NT	8±1.5	NT	NT	7±1.2
	9.77	142±11.4	9±1.2	15±1.0	39±3.1	8±2.9
	19.5	151±13.3	8±3.8	16±3.0	42±7.6	10±2.5
	39.1	186±12.7	16±5.0	16±4.7	47±13.1	10±2.1
	78.1	212±13.3	11±4.0	16±2.6	44±6.1	11±2.6
	156	115±22.1	NT	17±3.2	27±4.6	NT
	313	0±0.0	NT	0±0.0	0±0.0	NT

Applicant's summary and conclusion

Conclusions:

The test chemical did not induce gene mutation in Salmonella typhimurium strains TA100, TA1535, TA98, TA1535 and E. coli WP2 uvrA in the presence and absence of S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

Executive summary:

Gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical. The study was performed as per the OECD guideline 471 using Salmonella typhimurium strains TA100, TA1535, TA98, TA1535 and E. coli WP2 uvrA with and without of S9 metabolic activation system. The study was performed at various dose levels and in triplicate plates/dose. Concurrent solvent and positive control chemicals were incorporated in the study. The plates were observed for dose dependent increase in the number of revertnats/plate. The test chemical did not induce gene mutation in Salmonella typhimurium strains TA100, TA1535, TA98, TA1535 and E. coli WP2 uvrA in the presence and absence of S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.