Fatty acids, C18 unsaturated, C12-14 (even numbered) alkyl esters

Genetic toxicity: in vitro

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

Test material information

Constituent 1

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 results

Test results 1

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

Test results 2

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

Test results 3

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

Test results 4

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

Test results 5

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.