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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:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: well performed GLP and OECD guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1987
Report Date:
1987

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Qualifier:
according to
Guideline:
OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Species / strain / cell type:
S. typhimurium TA 1538
Species / strain / cell type:
E. coli WP2 uvr A
Metabolic activation:
with and without
Metabolic activation system:
Aroclor 1254(R) induced rat liver S9-mix
Test concentrations with justification for top dose:
Experiment I: 0, 4, 20, 100, 500, 2 500, 10 000 µg/plate
Experiment II: 0, 4, 20, 100, 500, 1 000, 2 500 (5 000) µg/plate
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO
- the test substance was dissolved in 100 µL respectively
Controls
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 9-aminoacridine, N-methyl-N-nitro-N-nitrosoguanidine, sodium azide, 2-nitrofluorene, 2-aminoanthracene, benzo[a]pyrene
Remarks:
without metabolic activation
Details on test system and experimental conditions:
METHOD OF APPLICATION:
in agar (plate incorporation)

DURATION
- Exposure duration: incubation for at least 48 to 72 hours

NUMBER OF REPLICATIONS: 3 plates per strain and dose level, including controls, two independent experiments

Evaluation criteria:
negative result: no significant and no dose dependant increase in the number of revertant colonies
Statistics:
Arithmetic means of the counted colonies were calculated.

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
positive
Remarks:
TA 1535 only
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Species / strain:
S. typhimurium TA 1538
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
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

 

Experiment I

Experiment II

Metabolic activation

Dose

µg/plate

TA 1535

TA 1538

Dose

µg/plate

TA 1535

TA 1538

 

 

Number of colonies (mean)

 

Number of colonies (mean)

 

0

10

12

0

23

13

 

4

14

13

4

21

8

 

20

15

8

20

25

20

 

100

11

16

100

18

21

 

500

25*

22

500

26

29

 

2 500

0*

0

1 000

3*

42

 

10 000

0*

0

2 500

0*

0*

X

0

12

23

0

24

29

X

4

11

26

4

16

28

X

20

9

27

20

17

32

X

100

14

27

100

13

29

X

500

21

26

500

33

34

X

2 500

56*

27*

2 500

0*

10*

X

10 000

0*

0*

5 000

0*

6*

*: incomplete bacterial lawn

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
positive

The test item did exert weak mutagenic activity in strains TA 1535 and TA 1538 of the Salmonella typhimurium and Escherichia coli reverse mutation assay (plate incorporation test) with and without metabolic activation.
Executive summary:

Mutagenic activity of the test item was investigated in Salmonella typhymurium strains 1535, 1537, 98, 100 and 1538 as well as Escherichia coli WP2 uvrA with and without metabolic activation (induced rat liver S9-mix) at concentrations of 0 to 10 000 µg/plate. Under the conditions tested the test compound did cause an increase in the number of revertant colonies of strains TA 1535 and TA 1538 with and without metabolic activation.

The test substance proved to be toxic at doses of 500 µg/plate and higher.

Therefore the test item is considered mutagenic under the conditions in this bacterial reverse mutation assay.