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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 from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Study period:
17 - 25 Feb 1988
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP guideline study with acceptable restrictions (analytical purity of test substance not specified, incomplete strain selection, only 2-AA used as positive control in the presence of S9 mix).

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1988
Report Date:
1988

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
yes
Remarks:
analytical purity of test substance not specified, incomplete strain selection, only 2-AA used as positive control in the presence of S9 mix
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): Isooctylstearate, Fatty acids, C16-18, 2-ethylhexyl esters
- Physical state: clear liquid
- Analytical purity: no data

Method

Target gene:
His operon
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Additional strain / cell type characteristics:
other: rfa-; uvrB- (R+ for TA 98 and TA100)
Species / strain / cell type:
S. typhimurium TA 1538
Additional strain / cell type characteristics:
other: rfa-; uvrB-
Metabolic activation:
with and without
Metabolic activation system:
S9-Mix (Spraque Dawley rats, male, Aroclor 1254 induced)
Test concentrations with justification for top dose:
8, 40, 200, 1000 and 5000 µg/plate in both experiments
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: Tween 80/bidest. water
Controlsopen allclose all
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
Tween 80/bidest. water
True negative controls:
no
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
TA1535 and TA100 without metabolic activation
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
Tween 80/bidest. water
True negative controls:
no
Positive controls:
yes
Positive control substance:
9-aminoacridine
Remarks:
TA1537 without metabolic activation
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
Tween 80/bidest. water
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 4-Nitro-o-phenylenediamine
Remarks:
TA1538 and TA98 without metabolic activation
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
Tween 80/bidest. water
Positive controls:
yes
Positive control substance:
other: 2-Aminoanthracene
Remarks:
All test strains with metabolic activation
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: 2 experiments were performed in triplicates each

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

OTHER: The spontaneous mutation rates of each tester strain were within the characteristic spontaneous mutation rates
Evaluation criteria:
A combination of the following criteria was considered as a positive result:
1) The plate background of non-reverted bacteria did not show any growth reduction versus the respective negative controls.
2) The spontaneous mutation rates of each tester strain per plate were within the characteristic spontaneous mutation range.
3) As a rule, the positive controls showed mutation rates exceeding the control values of TA 100 at least by the factor 2.0 and those of the other tester strains at least by the factor 3.0.
4) At more than one dose tested, the test substance caused at least a 2.0-fold increase in comparison with the negative controls in the tester strain TA 100. For the other tester strains, an increase in the mutation rate of more than 3.0 above the corresponding negative controls was considered positive.

Reproducibility:
If the test substance induces reverse mutations in only one test, and if this effect cannot be reproduced in one or several repeated tests, the initially positive test data will lose their significance.
Statistics:
Mean and standard deviation were calculated
Revertant colonies were counted and the mean and standard deviation were calculated and compared to the controls. The tester strains were regulary tested for their genetic markers.

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 / choice of top concentrations:
no 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:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Additional information on results:
COMPARISON WITH HISTORICAL CONTROL DATA: Yes

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 on bacteria - Experiment I

With or without S9-Mix

Test substance concentration

(μg/plate)

Mean number of revertant colonies per plate

(average of 3 plates)

TA 1535

TA 100

TA 1537

TA 1538

TA 98

-

Solvent (Tween 80)

7

71

6

10

15

-

8

8

73

4

7

13

-

40

8

85

5

8

16

-

200

12

80

9

6

21

-

1000

8

83

7

11

16

-

5000

11

107

5

9

13

Positive

controls

- S9

Name

SA

SA

9AA

4ND

4ND

Concentrations

(μg/plate)

2

2

80

40

40

Number of colonies/plate

307

256

198

1014

483

+

Solvent (Tween 80)

10

78

4

16

16

+

8

13

95

5

16

13

+

40

11

95

6

16

16

+

200

10

95

4

11

11

+

1000

11

106

6

25

14

+

5000

11

97

7

20

15

Positive

controls

+ S9

Name

2AA

2AA

2AA

2AA

2AA

Concentrations

(μg/plate)

2.5

5

2.5

5

5

Number of colonies/plate

104

1242

35

459

741

9AA = 9-Aminoacridine

2AA = 2-Aminoanthracene

SA = Sodium Acide

4ND = 4-Nitro-o-phenylenediamine

 

 Table 2: Mutagenicity on bacteria - Experiment II

With or without S9-Mix

Test substance concentration

(μg/plate)

Mean number of revertant colonies per plate

(average of 3 plates)

TA 1535

TA 100

TA 1537

TA 1538

TA 98

-

Solvent (Tween 80)

7

81

6

9

16

-

8

10

65

3

6

16

-

40

13

83

6

6

18

-

200

10

75

6

7

17

-

1000

11

75

5

6

18

-

5000

10

71

6

7

12

Positive

controls

- S9

Name

SA

SA

9AA

4ND

4ND

Concentrations

(μg/plate)

2

2

80

40

40

Number of colonies/plate

355

337

203

892

440

+

Solvent (Tween 80)

11

89

7

13

17

+

8

7

78

6

9

18

+

40

12

90

6

12

18

+

200

12

90

6

11

19

+

1000

14

89

6

16

17

+

5000

13

89

5

13

20

Positive

controls

+ S9

Name

2AA

2AA

2AA

2AA

2AA

Concentrations

(μg/plate)

2.5

5

2.5

5

5

Number of colonies/plate

126

1164

51

354

619

9AA = 9-Aminoacridine

2AA = 2-Aminoanthracene

SA = Sodium Acide

4ND = 4-Nitro-o-phenylenediamine

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative