2-ethylhexyl nonanoate

Genetic toxicity: in vitro

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:

25 Jul - 02 Aug 1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP-guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

incomplete strain selection

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

135800-37-2

EC Number:

603-931-6

Cas Number:

135800-37-2

IUPAC Name:

135800-37-2

Details on test material:

- Name of test material (as cited in study report): 2-Ethyl-hexylester with fatty acids C8-C14
- Physical state: liquid, clear,slight yellow
- Analytical purity: 100%
- Lot/batch No.: Partie 8 v.07.05.90
- Expiration date of the lot/batch: 06.05.1092
- Stability under test conditions: stable for 2 years
- Storage condition of test material: RT

Method

Target gene:

Genes involved in Histidine synthesis

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

S. typhimurium 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:

8, 40, 200, 1000 and 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: Tween 80/water (bidest.)
The suspension medium was choosen according to solubility properties tested in a preliminary experiment.

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

culture medium

Negative solvent / vehicle controls:

yes

Remarks:

Tween 80

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

2 µg/plate for TA 100 and TA 1535 without metabolic activation

Controls 2

Untreated negative controls:

yes

Remarks:

culture medium

Negative solvent / vehicle controls:

yes

Remarks:

Tween 80

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

80 µg/plate for TA 1537 without metabolic activation

Controls 3

Untreated negative controls:

yes

Remarks:

culture medium

Negative solvent / vehicle controls:

yes

Remarks:

Tween 80

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 4-nitro-o-phenylendiamine

Remarks:

40 µg/plate for TA 98 and TA 1538 without metabolic activation

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

2.5 µg/plate for TA 1535, TA 1537 and 5 µg/plate for TA 98, TA 100, TA 1538 (with S9 mix)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: 3

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:

The test material may be considered positive in this test system if the following criteria are met: For the test item to be considered mutagenic, two-fold (or more) increases in mean revertant numbers must be observed at two consecutive dose levels or at the highest practicable dose level only. In addition, there must be evidence of a dose-response relationship showing increasing numbers of mutant colonies with increasing dose levels.
All cultures must demonstrate the characteristic mean number of spontaneous revertants in the vehicle controls.

Statistics:

Means and standard deviations were calculated

Results and discussion

Test results

Test results 1

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

Test results 2

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	TA100	TA1537	TA1538	TA98
-	Buffer	8	102	10	11	30
-	Solvent (Tween80/H2O)	7	99	9	8	29
-	8	4	110	9	10	28
-	40	6	100	11	6	32
-	200	12	112	8	10	28
-	1000	12	97	10	11	31
-	5000	9	106	9	11	30
Positive controls - S9	Name	SA	SA	9AA	4ND	4ND
	Concentrations (μg/plate)	2	2	80	40	40
	Number of colonies/plate	297	311	413	1677	830
+	Buffer	6	93	8	14	26
+	Solvent (Tween80/H2O)	8	94	8	12	37
+	8	7	94	7	21	36
+	40	8	104	8	10	35
+	200	6	97	9	12	37
+	1000	8	97	7	9	40
+	5000	6	95	7	13	37
Positive controls + S9	Name	2AA	2AA	2AA	2AA	2AA
	Concentrations (μg/plate)	2.5	5	2.5	5	5
	Number of colonies/plate	107	1870	208	1566	1720

 

9AA = 9-Aminoacridine

2AA = 2-Aminoanthracene

SA = Sodium Acide

4ND = 4-Nitro-o-phenylendiamine

 

 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	TA100	TA1537	TA1538	TA98
	Buffer	9	99	7	9	30
-	Solvent (Tween80/H2O)	11	100	9	10	32
-	8	8	101	8	11	33
-	40	6	105	7	10	37
-	200	9	112	8	11	37
-	1000	8	107	10	12	39
	5000	13	100	11	10	32
Positive controls - S9	Name	SA	SA	9AA	4ND	4ND
	Concentrations (μg/plate)	2	2	80	40	40
	Number of colonies/plate	270	270	296	1648	1359
+	Buffer	9	108	9	11	35
+	Solvent (Tween80/H2O)	11	104	11	14	30
+	8	7	105	9	13	32
+	40	8	105	9	11	32
	200	7	121	5	11	38
+	1000	8	120	8	14	32
+	5000	7	112	7	10	41
Positive controls + S9	Name	2AA	2AA	2AA	2AA	2AA
	Concentrations (μg/plate)	2.5	5	2.5	5	5
	Number of colonies/plate	137	1774	253	1419	1810

 

9AA = 9-Aminoacridine

2AA = 2-Aminoanthracene

SA = Sodium Acide

4ND = 4-Nitro-o-phenylendiamine

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative