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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
3 (not reliable)
Rationale for reliability incl. deficiencies:
other: Test method equivalent or similar to OECD Guideline 471. Deviations: Only 4 Salmonella strains were tested.

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1987

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
yes
Remarks:
(Only 4 Salmonella typhimurium strains were tested).
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): bromochloromethane.

Method

Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 97
Species / strain / cell type:
S. typhimurium TA 98
Species / strain / cell type:
S. typhimurium TA 100
Species / strain / cell type:
S. typhimurium, other: TA 104
Metabolic activation:
with and without
Metabolic activation system:
S-9 mix (from rat livers with Aroclor 1254-pretreatment).
Test concentrations with justification for top dose:
10, 25, 50, 100, 250, 500 and 1000 µg/plate
Vehicle / solvent:
- Solvent used: Dimethyl sulfoxide (DMSO).
Controls
Negative solvent / vehicle controls:
yes
Remarks:
DMSO.
Positive controls:
yes
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation). The test compound was added on top agar in a volume of 0.1 ml.
NUMBER OF REPLICATIONS: 2 or 3

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 97
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
(at 1000 µg/plate)
Vehicle controls validity:
valid
Positive controls validity:
valid
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Positive controls validity:
valid
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Positive controls validity:
valid
Species / strain:
S. typhimurium, other: TA 104
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1. Mutagenicity of bromochloromethane (Ames-test).

Compound

Dose µg/plate

his+revertant colònies in strain

TA 97

TA 98

TA 100

TA 104

- S9

+S9

- S9

+S9

- S9

+S9

- S9

+S9

Bromochloromethane

1000

580 ± 21

tox.

78 ± 6

124 ± 4

340 ± 21

820 ± 28

746 ± 12

703 ± 21

500

680 ± 14

504 ± 19

40 ± 8

118 ± 5

436 ± 24

936 ± 26

748 ± 14

582 ± 17

250

852 ± 27

688 ± 21

23 ± 7

108 ± 6

392 ± 27

1000 ± 27

968 ± 17

672 ± 14

100

1030 ± 38

890 ± 26

32 ± 4

132 ± 9

379 ± 28

840 ± 21

940 ± 21

 580 ± 13

50

740 ± 24

798 ± 25

25 ± 6

146 ± 8

354 ± 21

920 ± 19

1136 ± 28

608 ± 10

25

822 ± 28

668 ± 23

20 ± 9

120 ± 9

331 ± 16

862 ± 21

1388 ± 31

640 ± 9

10

888 ± 24

632 ± 23

21 ± 6

90 ± 10

173 ± 14

800 ± 20

600 ± 12

600 ± 8

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
positive

The results of the bacterial reverse mutation assay on the test substance bromochloromethane were positive.
Executive summary:

A bacterial reverse mutation assay: plate incorporation method was performed with the test substance bromochloromethane. Salmonella typhimurium strains TA97 TA98, TA100 and TA 104 were exposed to 10 to 1000 ug/plate of the test substance with and without metabolic activation (S-9 mix). Negative and positive controls were included in the assay. Bromochloromethane showed positive responses in all the strain tested, with and without metabolic activation. Responses in TA 98 and TA 100 strains were enhanced with metabolic activation.