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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:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
1992-03-25 to 1992-04-02
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
yes
Remarks:
, analytical purity of test material not specified; incomplete strain selection;
GLP compliance:
yes
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): Lauric acid methyl ester
- Substance type: Fatty acid methyl ester
- Physical state: colourless liquid
- Analytical purity: not given
- Storage condition of test material: RT

Method

Target gene:
Genes involved in Histidine synthesis
Species / strainopen allclose all
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Additional strain characteristics:
other: rfa-; uvrB- (R+ for TA 98 and TA 100)
Metabolic activation:
with and without
Metabolic activation system:
S9-Mix (Wistery rats, male, Aroclor 1254 induced)
Species / strain:
S. typhimurium TA 1538
Additional strain characteristics:
other: rfa-; uvrB-
Metabolic activation:
with and without
Metabolic activation system:
S9-Mix (Wistar rats, male, Aroclor 1254 induced)
Test concentrations with justification for top dose:
0, 8, 40, 200, 1000 and 5000 µg/plate in both experiments

Vehicle:
- Vehicle(s)/solvent(s) used: acetone
To prevent toxic effects of the solvent medium the stock solution of the test substance was doubled and 50 µL/plate instead of 100 µl/plate was introduced in the test
Controlsopen allclose all
Negative controls:
yes
Remarks:
culture media
Solvent controls:
yes
Remarks:
Acetone
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
TA 100 and TA 1535 without metabolic activation
Negative controls:
yes
Remarks:
culture media
Solvent controls:
yes
Remarks:
Acetone
Positive controls:
yes
Positive control substance:
9-aminoacridine
Remarks:
TA 1537 without metabolic activation
Negative controls:
yes
Remarks:
culture media
Solvent controls:
yes
Remarks:
Acetone
Positive controls:
yes
Positive control substance:
other: 4-nitro-o-phenylendiamine
Remarks:
TA 98 and TA 1538 without metabolic activation
Negative controls:
yes
Solvent controls:
yes
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
For all strainn with metabolic activation (S9 mix, Aroclor induced)
Details on test system and conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 h
- Expression time (cells in growth medium): 48 h

DETERMINATION OF CYTOTOXICITY
- Method: Inspection of the bacterial background lawn

NUMBER OF REPLICATIONS: triplicates

OTHER: The spontaneous mutation rates of each tester strain were within the characteristic spontaneous mutation rates
Evaluation criteria:
The test material may be considered positive in this test system if the following criteria are met:
For the test item to be considered mutagenic, two-fold (or more) increases in mean revertant numbers must be observed at two consecutive dose levels or at the highest practicable dose level only. In addition, there must be evidence of a dose-response relationship showing increasing numbers of mutant colonies with increasing dose levels.
All cultures must demonstrate the characteristic mean number of spontaneous revertants in the vehicle controls.
Statistics:
Mean and standard deviation 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:
negative
Cytotoxicity:
yes
Remarks:
at 5000 µg/plate
Vehicle controls valid:
yes
Positive controls valid:
yes
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.
Species / strain:
S. typhimurium TA 1538
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
yes
Remarks:
at 5000 µg/plate
Vehicle controls valid:
yes
Positive controls valid:
yes
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.
Additional information on results:

COMPARISON WITH HISTORICAL CONTROL DATA: Yes

Any other information on results incl. tables

Table 1: Mutagenicity on bacteria - experiment I

 

With or without S9-Mix

Test substance concentration

(¿g/plate)

Mean number of revertant colonies per plate

(average of 3 plates)

TA 1535

TA100

TA1537

TA1538

TA98

 

Buffer

14

132

12

9

21

-

Solvent (Acetone)

15

133

10

13

26

-

8

11

122

9

6

18

-

40

10

96

8

12

16

-

200

10

109

8

11

16

-

1000

9

92

13

11

18

 

5000

10

122

10

11

13

Positive

controls

- S9

Name

SA

SA

9AA

4ND

4ND

Concentrations

(¿g/plate)

2

2

80

40

40

Number of colonies/plate

590

659

771

2408

1813

+

Buffer

16

158

11

28

35

+

Solvent (Acetone)

17

153

7

32

41

+

8

16

126

13

34

24

+

40

13

209

8

32

22

 

200

13

102

9

31

28

+

1000

13

112

7

18

24

+

5000

7

70

5

16

18

Positive

controls

+ S9

Name

2AA

2AA

2AA

2AA

2AA

Concentrations

(¿g/plate)

2.5

5

2.5

5

5

Number of colonies/plate

112

1532

137

1146

1555

 

9AA = 9-Aminoacridine

2AA = 2-Aminoanthracene

SA = Sodium Acide

4ND = 4-Nitro-o-phenylendiamine

 

 Table 2: Mutagenicity on bacteria - experiment II

With or without S9-Mix

Test substance concentration

(¿g/plate)

Mean number of revertant colonies per plate

(average of 3 plates)

TA 1535

TA100

TA1537

TA1538

TA98

 

Buffer

20

133

10

6

26

-

Solvent (Acetone)

20

123

12

6

16

-

8

16

128

9

8

21

-

40

16

115

7

6

15

-

200

13

109

7

8

21

-

1000

14

132

13

9

19

 

5000

17

110

11

11

28

Positive

controls

- S9

Name

SA

SA

9AA

4ND

4ND

Concentrations

(¿g/plate)

2

2

80

40

40

Number of colonies/plate

465

652

978

2055

1816

+

Buffer

18

125

11

23

42

+

Solvent (Acetone)

23

102

7

23

35

+

8

27

137

7

13

43

+

40

17

125

5

24

31

 

200

21

119

5

22

30

+

1000

19

105

8

18

27

+

5000

6

39

4

12

22

Positive

controls

+ S9

Name

2AA

2AA

2AA

2AA

2AA

Concentrations

(¿g/plate)

2.5

5

2.5

5

5

Number of colonies/plate

104

1127

137

738

831

 

9AA = 9-Aminoacridine

2AA = 2-Aminoanthracene

SA = Sodium Acide

4ND = 4-Nitro-o-phenylendiamine

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative Under the tested experimental conditions the test substance did not induce gene mutations in S. typhimurium strains up to the maximum dose.