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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2001
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2001
Report Date:
2001

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Version / remarks:
1998
Deviations:
no
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: liquid

Method

Species / strain
Species / strain:
other: Salmonella typhimurium TA98, TA100, TA1535 and TA1537; Escherichia coli WP2uvrA
Metabolic activation:
with and without
Metabolic activation system:
Aroclor induced rat liver S9
Test concentrations with justification for top dose:
preliminary toxicity test: 0.13 to 5000 µg/plate; definitive assay:15 to 5000 µg/plate
Vehicle:
- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: request of sponsor; compatibility with target cells; solubility of test article
Controlsopen allclose all
Negative controls:
no
Solvent controls:
yes
Remarks:
DMSO
True negative controls:
no
Positive controls:
yes
Positive control substance:
2-nitrofluorene
Remarks:
TA 98 without activation
Negative controls:
no
Solvent controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
TA 100 and TA 1535 without activation
Negative controls:
no
Solvent controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
9-aminoacridine
Remarks:
TA 1537 without activation
Negative controls:
no
Solvent controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
methylmethanesulfonate
Remarks:
WP2 uvrA without activation
Negative controls:
no
Solvent controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
All strains with activation
Details on test system and conditions:
METHOD OF APPLICATION: preincubation;

DURATION
- Preincubation period: 60 minutes
- Exposure duration: 48-72 hours
- Expression time (cells in growth medium): 48-72 hours
- Fixation time (start of exposure up to fixation or harvest of cells): 48-72 hours

NUMBER OF REPLICATIONS: triplicate cultures

DETERMINATION OF CYTOTOXICITY
- Method: other: condition of bacterial lawn

METABOLIC ACTIVATION: S9 was prepared from male Sprague-Dawley rats induced with Aroclor 1264. Each batch was assayed for ability to metabolise 2-aminoanthracene and 7,12-dimethylbenz(a)anthracene to forms mutagenic to S. typhimurium TA100. S9 mix contained 10% S9, 5mM glucose-6-phosphate, 4 mM NADP, 8 mM MgCl2 and 33 mM KCl in 100 mM phosphate buffer pH 7.4. 0.5 ml of S9 mix were added to 2.0 ml top agar, 0.1 ml tester strain and 0.05 ml vehicle or test article, giving a final concentration of approximately 2% S9.
Evaluation criteria:
For the test article to be evaluated positive, it must cause a dose-related increase in the mean no. of revertants per plate relative to solvent control over a minimum of two concentrations; by at least 2-fold in strains TA 98, TA 100 and E coli WP2 uvrA; by at least 3-fold in strains TA 1535 and 1537
Statistics:
Means and standard deviations were calculated

Results and discussion

Test results
Species / strain:
other: Salmonella typhimurium TA98, TA100, TA1535 and TA1537; Escherichia coli WP2uvrA
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
other: > 1500 μg/plate
Vehicle controls valid:
yes
Negative controls valid:
not applicable
Positive controls valid:
yes
Remarks on result:
other: No mutagenic potential
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: no information
- Effects of osmolality: no information
- Evaporation from medium: no information
- Water solubility: reacts slowly with water
- Precipitation: no precipitate observed


RANGE-FINDING/SCREENING STUDIES: on all strains

COMPARISON WITH HISTORICAL CONTROL DATA: Control results were within the range of historical data

ADDITIONAL INFORMATION ON CYTOTOXICITY: slightly variable between studies

Any other information on results incl. tables

Table 1: Dose range-finding study. Number of revertants per plate (1 plate per strain)

Conc. µg/plate

TA98

 

 

TA100

 

 

TA1535

 

 

 

- MA

+ MA

Cytotoxic (yes/no)

- MA

+ MA

Cytotoxic (yes/no)

- MA

+ MA

Cytotoxic (yes/no)

0*

15

15

no

84

102

no

11

14

no

6.7

16

14

no

88

109

no

10

14

no

10

15

17

no

94

122

no

10

9

no

33

15

15

no

109

110

no

11

12

no

67

19

15

no

93

101

no

13

13

no

100

11

18

no

72

104

no

17

10

no

333

17

17

no

116

117

no

8

13

no

667

15

14

no

86

115

no

12

8

no

1000

11

20

no

60

80

no

6

11

no

3333

8

15

Yes**

75

102**

Yes

4***

7***

Yes

5000

0

13**

Yes****

69***

48***

yes

0****

4***

yes

*solvent control with Ethylene glycol dimethyl ether

** Background lawn slightly reduced

***Background lawn severely reduced

****Background lawn extremely reduced

Table 2: Dose range-finding study. Number of revertants per plate (1 plate per strain)

Concentration (μg/Plate)

TA100

 

 

WP2 uvrA

 

 

 

Plate 1

- MA

Plate 2

+ MA

Cytotoxic (yes/no)

Plate 1

- MA

Plate 2

+ MA

Cytotoxic (yes/no)

0*

5

5

no

11

11

no

6.7

7

8

no

14

13

no

10

7

6

no

11

8

no

33

3

6

no

12

11

no

67

7

4

no

12

11

no

100

5

6

no

11

11

no

333

3

5

no

10

12

no

667

4

2

no

7

12

no

1000

5

6

no

7

13

no

3333

5***

7**

Yes

6

7

No

5000

1****

5***

yes

2**

13

yes

*solvent control with Ethylene glycol dimethyl ether

** Background lawn slightly reduced

***Background lawn severely reduced

****Background lawn extremely reduced

 

 

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

Conc. µg/plate

TA98

 

 

TA100

 

 

TA1535

 

 

 

- MA

+ MA

Cytotoxic (yes/no)

- MA

+ MA

Cytotoxic (yes/no)

- MA

+ MA

Cytotoxic (yes/no)

0*

15

19

no

100

103

no

12

10

no

15

17

16

no

995

91

no

11

9

no

50

14

20

no

102

91

no

9

13

no

150

10

18

no

106

94

no

11

12

no

500

9

19

no

116

113

no

12

9

no

1500

7

16

Yes

6

100

Yes

8

7

no

5000

0

3

Yes

0

0

Yes

0

0

Yes

Positive control

324

499

-

451

458

-

152

74

-

*solvent control with Ethylene glycol dimethyl ether

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

Concentration (μg/Plate)

TA1537

 

 

WP2 uvrA

 

 

 

- MA

+ MA

Cytotoxic (yes/no)

- MA

+ MA

Cytotoxic (yes/no)

0*

6

8

no

11

11

no

15

6

6

no

10

12

no

50

4

6

no

9

10

no

150

5

6

no

10

11

no

500

3

5

no

11

10

no

1500

4

4

no

9

11

no

5000

0

0

yes

4

6

yes

Positive control

20

65

-

227

76

-

*solvent control with Ethylene glycol dimethyl ether

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

Conc. µg/plate

TA98

 

 

TA100

 

 

TA1535

 

 

 

-MA

+MA

Cytotoxic (yes/no)

-MA

+MA

Cytotoxic (yes/no)

-MA

+MA

Cytotoxic (yes/no)

0*

15

23

no

116

135

no

12

9

no

15

14

30

no

126

151

no

13

6

no

50

18

22

no

129

147

no

9

9

no

150

18

25

no

111

154

no

10

9

no

500

15

17

no

133

149

no

10

7

no

1500

17

19

no

133

122

no

15

6

no

5000

7

8

yes

77

57

yes

8

8

no

Positive control

589

951

-

509

706

-

228

163

-

*solvent control withEthylene glycol dimethyl ether

 

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

Concentration (μg/Plate)

TA1537

 

 

WP2 uvrA

 

 

 

- MA

+ MA

Cytotoxic (yes/no)

- MA

+ MA

Cytotoxic (yes/no)

0*

4

7

no

14

12

no

15

4

6

no

13

8

no

50

6

5

no

12

10

no

150

6

7

no

12

6

no

500

8

5

no

15

11

no

1500

6

7

no

11

7

no

5000

7

3

yes

9

8

no

Positive control

935

317

-

219

275

-

 

Applicant's summary and conclusion

Conclusions:
3-Trimethoxysilylpropyl methacrylate has been tested in a valid bacterial reverse mutation assay according to OECD TG 471 and under GLP, using Salmonella typhimurium TA98, TA100, TA1535 and TA1537 and Escherichia coli WP2uvrA. No increase in the number of revertants was observed in any test strain, with or without activation. Appropriate positive and solvent controls were added and gave expected results. It is concluded that the test substance is negative for bacterial mutagenicity under the conditions of the test.