Registration Dossier

Diss Factsheets

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

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

Constituent 1
Chemical structure
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  15   
Positive controls 552  331   
Veh. control  62   
17  TA1537 
3.09  13  14   
9.26  12  14   
27.78  17   
83.33  16   
250.00   
Pos controls  1510  120   
Veh.   20   
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   
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   
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.