Bromoacetic acid

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

Study period:

From June to July 1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

and protocol B.14 "Salmonella typhimurium reverse mutation Assay" of EEC Directive 84/449

GLP compliance:

yes

Type of assay:

bacterial gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Bromoacetic acid

EC Number:

201-175-8

EC Name:

Bromoacetic acid

Cas Number:

79-08-3

Molecular formula:

C2H3BrO2

IUPAC Name:

2-bromoacetic acid

Details on test material:

- Name of test material (as cited in study report): Monobromoacetic acid
- Substance type: White crystalline compound
- Physical state: Solid

Method

Target gene:

The Ames test was conducted by using the histidine requiring Salmonella typhimurium mutants TA 1535, TA 1537, TA 1538, TA 98 and TA 100 as indicator strains and a liver microsome fraction of Aroclar-induced rats for metabolic activation.

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

5 days after the injection of Aroclor 12511 the rats are killed by CO2. The livers are then removed cut in pieces and homogenized in 0.15 M KCl solution. The homogenate is centrifuged for 10 minutes at 9000 g. The supernatant is the metabolic activation.

Test concentrations with justification for top dose:

0, 30.9, 92.6, 277.8, 833.3 and 2500.0 µg/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: No justification of choice reported in the report.

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

- sodium acide for strains TA 1535 and TA 100 in the absence of S-9 mix - 9-aminoacridine for strain TA 1537 in the absence of S-9 mix - 2-nitrofluorene for strains TA 1538 and TA 98 in the absence of S-9 mix -2-aminoanthracene for all strains + S-9 mix

Details on test system and experimental conditions:

- Way of application: Stock solutions: Bromoacetic acid was dissolved in DMSO.
The bacterial suspensions (0.1 mL) were mixed with soft agar (2.0 mL, supplemented with l-histidine and trypophane respectively), 0.1 mL of
Bromoacetic acid stock solutions or vehicle control, 0.5 mL S9 mix (for experiments in presence of metabolic activation) or 0.5 ml sodium phosphate 100 mM (for experiments in absence of metabolic activation) before being pured onto minimal agar plates.
The plates were then incubated for 3 days at 37°C. All determinations were made in triplicates.
- Pre-incubation time: None
- Other modifications: None

Evaluation criteria:

- Number of cells evaluated:
Mutagenicity: frequency of revertant colonies
A positive response in the assay system is taken to be a two-fold or greater increase in the mean number of revertant colonies appearing in the test plates over and above the background spontaneous reversion rate observed with the vehicle, together with evidence of a dose response.

Statistics:

A positive response in the assay system is taken to be a two-fold or greater increase in the mean number of revertant colonies appearing in the test plates over and above the background spontaneous reversion rate observed with the vehicle, together with evidence of a dose
response

Results and discussion

Test results

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:

other: At the highest dose level used the test substance was slightly toxic for TA 1535, TA 1537 (with both +S9 and -S9) and TA 1538 (with -S9)

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

- Without metabolic activation: None of the observed results fulfilled the criteria of a positive response
Positive control compounds gave a clear positive result.

- With metabolic activation: None of the observed results fulfilled the criteria of a positive response
Positive control compounds gave a clear positive result.

- Cytotoxicity Preliminary test: A preliminary test was carried out to assess the toxicity of the test substance for TA 98. The results show that the test substance was toxic for the bacteria at dose levels of 500 μg/plate and higher, while no toxicity was observed at dose levels of 50 μg/plate and lower. In view of these observations, 250 μg per plate was chosen as the highest dose level for the mutagenicity study.

Result preliminary test: 500 μg/plate

- Main study: A positive response in the assay system is taken to be a two-fold or greater increase in the mean number of revertant colonies appearing in the test plates over and above the background spontaneous reversion rate observed with the vehicle, together with evidence of a dose response.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Gene Mutation Assay results:

Concentration [μg/plate or other]	Number of mutant cells (mean)		Strain
	-S9	+S9	TA 1535
0	39	26
3.09	36	22
9.26	32	22
27.78	41	25
83.33	26	25
250.00	6	15
Positive controls	552	331
Veh. control	62	-
0	9	17	TA1537
3.09	13	14
9.26	12	14
27.78	9	17
83.33	5	16
250.00	3	8
Pos controls	1510	120
Veh.	20	-
0	20	38	TA 1538
3.09	17	45
9.26	24	40
27.78	22	45
83.33	20	45
250.00	15(1)	40	(1) slightly less dense background lawn of bacterial growth
Pos. controls	904	809
Veh.Control	12	-
0	30	49	TA98
3.09	31	55
9.26	31	55
27.78	33	43
83.33	40	57
250.00	30	56
Pos. controls	663	1252
Veh. Control	38	-
0	180	180	TA100
3.09	193	196
9.26	210	187
27.78	183	180
83.33	201	208
250.00	221	197
Pos. controls	620	1442
Veh. Control	30	-

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Bromoacetic acid was examined for mutagenic activity in the Ames test using the histidine requiring Salmonella typhimurlum mutants TA 1535, TA 1 537, TA 1 538, TA 98 and TA 100 as indicator strains both in presence and absence of a liver microsome fraction of Aroclor-induced rats for metabolic activation (S-9 mix). Bromoacetic acid did not show at any concentration (max. 250 μg/plate) any mutagenic activity in any of the S. typhimurium strains, either in the
absence or in the presence of the S-9 mix. Based on this results Bromoacetic acid is not mutagenic.

Executive summary:

* Materials and methods:

Evaluation of the in vitro gene mutation potential in S. typhimurium strains (TA 1535, TA 1537, TA 98, TA 100, TA 1538); no relevant

deviation from guidelines (2000/32/EC B.14, OECD 471)

* Results and discussion:

Bromoacetic acid did not show any mutagenic activity in the Salmonella/mammalian microsome mutagenicity test under the

conditions employed in this study.

* Conclusion:

Bromoacetic acid was examined for mutagenic activity in the Ames test using the histidine requiring Salmonella typhimurlum mutants TA 1535, TA 1 537, TA 1 538, TA 98 and TA 100 as indicator strains both in presence and absence of a liver microsome fraction of Aroclor-induced rats for metabolic activation (S-9 mix).

Bromoacetic acid did not show at any concentration (max. 250 μg/plate) any mutagenic activity in any of the S. typhimurium strains, either in the absence or in the presence of the S-9 mix.

Based on this results Bromoacetic acid is not mutagenic.