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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
Study period:
1997-08-07 to 1997-09-19
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to the appropriate OECD test guideline, and in compliance with GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1997
Report Date:
1997

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
yes
Remarks:
Properties of test substance not determined by testing laboratory
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:
E. coli WP2 uvr A
Metabolic activation:
with and without
Metabolic activation system:
Aroclor induced rat liver S9
Test concentrations with justification for top dose:
75-5000 µg/plate (Test 1); 33-5000 µg/plate (Test 2)
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO

- Justification for choice of solvent/vehicle: Solubility properties and relative non-toxicity to bacteria
Controlsopen allclose all
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
All Strains (with activation)
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
2-nitrofluorene
Remarks:
TA 98 (without activation)
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
TA 100 TA 1535 (without activation)
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
9-aminoacridine
Remarks:
TA 1537 (without activation)
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
methylmethanesulfonate
Remarks:
WP2 uvrA (without activation)
Details on test system and experimental conditions:
METHOD OF APPLICATION: preincubation

DURATION
- Preincubation period: 60 minutes

- Expression time (cells in growth medium): 48 - 72 hours

- Fixation time (start of exposure up to fixation or harvest of cells): 12 hours

NUMBER OF REPLICATIONS: 3 plates for each test concentration

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Evaluation criteria:
All Salmonella tester strain cultures must demonstrate the presence of the deep rough mutation and the deletion of the uvrB gene.

Cultures of tester strains TA 98 and TA 100 must demonstrate the presence of the pKM101 plasmid R-factor.

All WP2uvrA cultures must demonstrate the deletion in the uvrA gene.

Results must be within range of historical data: TA 98 10-50, TA 100 80-240, TA 1535 5-45, TA 1537 3-21, WP2uvrA 10-60.

A result is positive if the number of revertants is significantly increased compared with the solvent control to at least 2-fold of the solvent control for TA 98, TA 100 and WP2uvrA and 3-fold of the solvent control for TA 1535 and TA 1537 in both experiments.

Positive results have to be reproducible and the histidine independence of the revertants has to be confirmed by streaking on histidine-free agar
plates.

Cytotoxicity is defined as a reduction in the mean number of revertants per plate by >50% compared with the mean vehicle control. The reduction
must be accompanied by an abrupt dose-dependant drop in the revertant count, and/or a reduction in background lawn.

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:
cytotoxicity
Remarks:
600 - 5000 µg/plate
Vehicle controls validity:
valid
Untreated negative controls validity:
not applicable
Positive controls validity:
valid
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
5000 µg/plate, without activation
Vehicle controls validity:
valid
Untreated negative controls validity:
not applicable
Positive controls validity:
valid
Additional information on results:
COMPARISON WITH HISTORICAL CONTROL DATA: Results were within range of historical control data

Any other information on results incl. tables

Table 2: Dose range-finding study, Number of revertants per plate (2 plates per strain)

TA 100

WP2 uvrA

Concentration (µg/Plate)

Plate 1

+ MA

Plate 2

- MA

Cytotoxic (Yes/No)

Plate 1

+ MA

Plate 2

- MA

Cytotoxic (Yes/No)

0

130

95

No

17

9

No

6.7

137

102

No

8

15

No

10

120

105

No

15

14

No

33

135

100

No

16

7

No

67

102

91

No

15

15

No

100

114

105

No

31

12

No

333

138

103

No

13

19

No

667

135

89

No

17

18

No

1000

95

98

No

15

16

No

3333

60

89

No

11

15

No

5000

59

66

No

11

9

Yes

*solvent control with DMSO

Table 3: Experiment 1 Mutagenicity Assay, Number of revertants per plate (mean of 3 plates)

 

TA98

TA100

TA1535

Conc.
µg/plate

— MA

+

MA

Cytotoxic
(yes/no)

MA

+

MA

Cytotoxic
(yes/no)

MA

+ MA

Cytotoxic
(yes/no)

0*

14

16

No

112

125

No

10

12

No

75

16

18

No

129

119

No

8

8

No

200

16

18

No

100

140

No

9

7

No

600

13

17

No

109

118

No

6

9

No

1800

7

15

No

8

70

Yes

3

10

Yes

5000

0

17

Yes

0

61

Yes

0

10

Yes

Positive control

553

1377

No

528

1103

No

397

100

No

*solvent control with DMSO

Table 4: Experiment 1 Mutagenicity Assay, Number of revertants per plate (mean of 3 plates)

 

TA1537

WP2uvrA

Conc.
µg/plate

— MA

+ MA

Cytotoxic
(yes/no)

— MA

+ MA

Cytotoxic
(yes/no)

0*

5

7

No

13

15

No

75

3

5

No

15

14

No

200

4

4

No

15

15

No

600

1

4

Yes

14

17

No

1800

1

1

Yes

11

14

No

5000

0

2

Yes

1

15

Yes

Positive control

860

141

No

389

407

No

*solvent control with DMSO

Table 5: Experiment 2 Mutagenicity Assay, Number of revertants per plate (mean of 3 plates)

 

TA98

TA100

TA1535

Conc.µg/plate

— MA

+

MA

Cytotoxic
(yes/no)

MA

+ MA

Cytotoxic
(yes/no)

MA

+ MA

Cytotoxic
(yes/no)

0*

12

18

No

131

140

No

9

11

No

33

13

17

No

112

134

No

9

11

No

100

13

13

No

98

124

No

7

9

No

333

12

13

No

123

117

No

8

9

No

1000

12

17

No

104

105

No

6

7

No

5000

10

7

Yes

30

67

Yes

1

4

Yes

Positive control

749

1149

No

645

986

No

482

94

No

*solvent control with DMSO

Table 6: Experiment 2 Mutagenicity Assay, Number of revertants per plate (mean of 3 plates)

 

TA1537

WP2 uvrA

Conc.
µg/plate

— MA

+ MA

Cytotoxic
(yes/no)

— MA

+ MA

Cytotoxic
(yes/no)

0*

5

8

No

13

14

No

33

5

4

No

13

11

No

100

5

4

No

13

11

No

333

5

5

No

11

10

No

1000

3

3

Yes

13

9

No

5000

1

1

Yes

5

12

Yes

Positive control

638

110

No

402

248

No

*solvent control with DMSO

Applicant's summary and conclusion

Conclusions:
Interpretation of results: negative with and without metabolic activation

3-(trimethoxysilyl)propylamine has been tested in a valid and reliable study according to OECD 471 and under GLP. No mutagenic effect was observed for the test substance tested up to limit concentration in any of the test strains with and without metabolic activation in Salmonella typhimurium strains TA 98, 100, 1535, 1537 and E.coli WP2 uvrA. The result of the first experiment was confirmed in an independent repeat experiment. It is concluded that the test substance is negative for mutagenicity to bacteria under the conditions of the test.