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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:
weight of evidence
Study period:
1994
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1994
Report date:
1994

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Version / remarks:
adopted 1981
Deviations:
yes
Remarks:
limited information on test material and methods; five S. typhimurium strains tested, but no TA 102 or E. coli strain included
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
Tetradecyl myristate
EC Number:
221-787-9
EC Name:
Tetradecyl myristate
Cas Number:
3234-85-3
Molecular formula:
C28H56O2
IUPAC Name:
tetradecyl myristate
Details on test material:
- Name of test material (as cited in study report): [only trade name given]
- Lot/batch No.: 10064017-8.6.94

Method

Target gene:
his operon
Species / strain
Species / strain / cell type:
S. typhimurium, other: TA 98, TA 100, TA 1535, TA 1537, TA 1538
Metabolic activation:
with and without
Metabolic activation system:
Cofactor supplemented post-mitochondrial fraction (S9 mix), prepared from the livers of rats treated with Aroclor 1254
Test concentrations with justification for top dose:
0.1, 1, 10, 100, 500 and 1000 µg/plate
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: ethanol
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: sodium azide (2 μg/plate, -S9, TA 100, TA 1535), nitrofluorene (2 µg/plate, -S9, TA 98, TA 1537, TA 1538), 2 -aminoanthracene (1 μg/plate, -S9, TA 98, TA 100, TA 1535, TA 1537, TA 1538; 1 μg/plate, +S9, TA 98, TA 100, TA 1535, TA 1537, TA 1538)
Details on test system and experimental conditions:
METHOD OF APPLICATION: preincubation

NUMBER OF REPLICATIONS: 3 replicates in 1 experiment for TA 98, TA 100, TA 1535 and TA 1537. 3 replicates in 2 independent experiments for TA 1538.

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Results and discussion

Test resultsopen allclose all
Key result
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
at 1000 µg/plate without metabolic activation
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
at 10 µg/plate and above without metabolic activation
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 1535
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 1537
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 1538
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
RANGE-FINDING/SCREENING STUDIES: in a range-finding study, a range of concentrations 0.1-1000 µg/plate was tested with TA 98 and TA 100, with and without metabolic activation. The solubility limit was 1000 µg/plate. More than 50% cytotoxicity was observed from 10 µg/plate in TA 100 and at 1000 µg/plate in TA 98; in both strain without metabolic activation.

ADDITIONAL INFORMATION ON CYTOTOXICITY: more than 50% cytotoxicity was observed in the range-finding study with TA 98 from 10 µg/plate and with TA 100 from 1000 µg/plate; without metabolic activation for both strains (see Table 1).

Any other information on results incl. tables

Table 1: Cytotoxicity measured in two strains

 

 

Survival/plate*

 

TA 98

TA 100

Test substance (µg/plate)

-S9

+S9

-S9

+S9

Control

1.0

1.0

1.0

1.0

0.1

0.6

1.0

0.8

1.0

1

0.6

0.9

0.5

0.9

10

0.4

0.8

0

0.9

100

0.4

0.9

0

0.8

500

0.4

1.0

0

0.8

1000**

0.2

0.9

0

0.9

* survival ratio treated : control

** solubility limit

Table 2: Test results

 

With or without S9-Mix

Test substance concentration

(μg/plate)

Mean number of revertant colonies per plate

(average of 3 plates)

Base-pair substitution type

Frameshift type

TA 100

TA 1535

TA 1538*

TA 98

TA 1537

-

Culture medium

162

7

10

25

5

Ethanol

153

7

10

25

4

-

0.05

-

-

-

33

5

-

0.1

191

6

12

26

4

-

0.5

173

7

10

29

4

1

199

6

11

30

3

5

173

6

13

26

4

10

171

4

12

-

-

-

40

-

-

-

-

-

-

160

-

-

-

-

-

640

-

-

-

-

-

1000

-

-

-

-

-

Positive controls, –S9

Name

SA

SA

NF

NF

NF

Concentrations

(μg/plate)

1.0

1.0

2.0

2.0

2.0

Mean No. of colonies/plate

(average of 3)

779

277

1840

1602

559

Positive controls, –S9

Name

2AA

2AA

2AA

2AA

2AA

Concentrations

(μg/plate)

1.0

1.0

1.0

1.0

1.0

Mean No. of colonies/plate

(average of 3)

215

7

13

40

8

+

Culture medium

148

8

11

34

6

+

Ethanol

150

6

14

33

6

+

0.05

-

-

-

-

-

+

0.1

-

-

-

-

-

+

0.5

-

-

-

-

-

+

1

-

-

-

35

5

+

5

-

-

-

-

-

+

10

175

6

13

37

7

+

40

176

6

15

35

4

+

160

163

5

17

38

3

+

640

149

6

15

40

6

+

1000

161

6

14

-

-

Positive controls, +S9

Name

2AA

2AA

2AA

2AA

2AA

Concentrations

(μg/plate)

1.0

1.0

1.0

1.0

1.0

Mean No. of colonies/plate

(average of 3)

1905

145

1478

1903

238

* 2 experiments, 6 plates in total

NF = nitrofluorene

SA = sodium azide

2AA = 2-Aminoanthracene

Applicant's summary and conclusion

Conclusions:
Based on the number of revertant colonies it can be stated that the test item is not mutagenic in this bacterial test system either with or without metabolic activation.
Executive summary:

Tetradecyl myristate, a constituent of the registration substance, was tested for mutagenicity with five strains of S. thyphimurium, both in the presence and absence of S9 mix. Six different doses from 0.1 to 1000 µg/plate were used in the preincubation assay. The solubility limit was 1000 µg/plate. More than 50% cytotoxicity was observed from 10 µg/plate in TA 100 and at 1000 µg/plate in TA 98; in both strain without metabolic activation.

Based on the number of revertant colonies it can be stated that the test item is not mutagenic in this bacterial test system either with or without metabolic activation.

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