1,2-Ethanediol, reaction products with branched 2-[(4-nonylphenoxy)methyl]oxirane

Genetic toxicity: in vitro

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study (OECD 471)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

(July 21, 1997)

Deviations:

yes

Remarks:

(2-aminoanthracene as sole indicator for the function of S9 mix)

GLP compliance:

yes (incl. QA statement)

Remarks:

(BASF SE, Experimental Toxicology and Ecology, Ludwigshafen, Germany)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

1-(2-hydroxyethoxy)-3-[4-(2-methyloctyl)phenoxy]propan-2-ol; 2-(2-hydroxyethoxy)-3-[4-(2-methyloctyl)phenoxy]propan-1-ol

EC Number:

807-586-4

Cas Number:

634602-80-5

Molecular formula:

Unspecified

IUPAC Name:

1-(2-hydroxyethoxy)-3-[4-(2-methyloctyl)phenoxy]propan-2-ol; 2-(2-hydroxyethoxy)-3-[4-(2-methyloctyl)phenoxy]propan-1-ol

Method

Target gene:

his- / trp-gene

Species / strain

Species / strain 1

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not specified

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

S9 mix obtained from phenobarbital and β-naphthoflavone induced rat livers

Test concentrations with justification for top dose:

1st Experiment (standard plate test): 33, 100, 333, 1000, 2500 and 5000 μg/plate
2nd Experiment (preincubation test): 3.3, 10, 33, 100, 333 and 1000 μg/plate (Salmonella strains); 33, 100, 333, 1000, 2500 and 5000 μg/plate (E. coli WP2 uvrA)

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Due to the limited solubility of the test substance in ultrapure water, DMSO was used as vehicle, which had been demonstrated to be suitable in bacterial reverse mutation tests and for which historical control data were available.

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

other: 2-aminoanthracene, N-methyl-N'nitrosoguanidine, 4-nitro-o-phenylenediamine

Remarks:

+ S9: 2-AA (TA 1535, TA 100, TA 1537, TA 98: 2.5 µg/plate; E. coli WP2 uvrA: 60 µg/plate); -S9: MNNG (TA 1535, TA 100: 5 μg/plate); NOPD (TA 98: 10 µg/plate); AAC (TA 1537: 100 µg/plate); 4-NQO (E. coli WP2 uvrA: 5 µg/plate)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation); preincubation

DURATION
- Preincubation period: about 20 min (preincubation test)
- Exposure duration: 48 - 72 h

NUMBER OF REPLICATIONS: 3 plates per dose or control

DETERMINATION OF CYTOTOXICITY
- Method: decrease in the number of revertants, clearing or diminution of the background lawn (= reduced his- or trp-background growth), reduction in the titer

OTHER:
The titer was determined only in the experimental parts with S9 mix both for the negative controls (vehicle only) and for the two highest doses in all experiments.

Evaluation criteria:

Acceptance criteria:
Generally, the experiment is considered valid if the following criteria are met:
- The number of revertant colonies in the negative controls was within the range of the historical negative control data for each tester strain.
- The sterility controls revealed no indication of bacterial contamination.
- The positive control substances both with and without S9 mix induced a distinct increase in the number of revertant colonies within the range of the historical positive control data or above.
- Fresh bacterial culture containing approximately 10^9 cells per mL were used. For approval the titer of viable bacteria was ≥ 10^8 colonies per mL.

Assessment criteria:
The test substance is considered positive in this assay if the following criteria are met:
- A dose-related and reproducible increase in the number of revertant colonies, i.e. about doubling of the spontaneous mutation rate in at least one tester strain either without S9 mix or after adding a metabolizing system.
A test substance is generally considered non-mutagenic in this test if:
- The number of revertants for all tester strains were within the historical negative control range under all experimental conditions in at least two experiments carried out independently of each other.

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:

cytotoxicity

Remarks:

(from about 333 μg/plate onward depending on the strain and test conditions)

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(from about 333 μg/plate onward depending on the strain and test conditions)

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: Test substance precipitation was found from about 333 μg/plate onward with and without S9 mix.

COMPARISON WITH HISTORICAL CONTROL DATA: yes

ADDITIONAL INFORMATION ON CYTOTOXICITY: A bacteriotoxic effect (reduced his-background growth, decrease in the number of his+ or trp+ revertants, reduction in the titer) was observed in the standard plate test depending on the strain and test conditions from about 333 μg/plate onward. In the preincubation assay bacteriotoxicity (decrease in the number of his+ or trp+ revertants, slight reduction in the titer) was observed depending on the strain and test conditions from about 333 μg/plate onward.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1. Test results of experiment 1 (standard plate test)
With or without S9-Mix	Test substance concentration	Mean number of revertant colonies per plate
	(μg/plate)	(average of 3 plates ± Standard deviation)
		TA 100	TA 1535	E. coli WP2 uvrA	TA 98	TA 1537
–	0	56 ± 7	10 ± 2	69 ± 8	18 ± 2	6 ± 1
–	33	66 ± 6	11 ± 3	70 ± 7	17 ± 3	5 ± 2
–	100	53 ± 8	10 ± 2	72 ± 5	15 ± 2	5 ± 3
–	333	43 ± 3P	8 ± 1P	63 ± 2P	14 ± 3P	5 ± 2P
–	1000	11 ± 3P	3 ± 1P	59 ± 5P	8 ± 2P	4 ± 1P
–	2500	0B/P	0B/P	56 ± 2P	0B/P	0B/P
–	5000	0B/P	0B/P	28 ± 3P	0B/P	0B/P
Positive controls, –S9	Name	MNNG	MNNG	4-NQO	NOPD	AAC
	Concentrations (μg/plate)	5	5	5	10	100
	Mean No. of colonies/plate (average of 3 ± SD)	705 ± 61	923 ± 57	806 ± 30	490 ± 69	464 ± 51
+	0	85 ± 8	11 ± 2	68 ± 3	26 ± 7	7 ± 1
+	33	87 ± 11	13 ± 3	69 ± 5	25 ± 3	7 ± 2
+	100	79 ± 9	14 ± 2	68 ± 2	31 ± 8	6 ± 1
+	333	68 ± 8P	12 ± 2P	75 ± 6P	21 ± 3P	5 ± 1P
+	1000	44 ± 10P	8 ± 2P	73 ± 8P	22 ± 3P	4 ± 1P
+	2500	16 ± 6B/P	3 ± 1B/P	62 ± 2P	17 ± 3B/P	2 ± 1B/P
+	5000	0B/P	0B/P	45 ± 5P	0B/P	0B/P
Positive controls, –S9	Name	2AA	2AA	2AA	2AA	2AA
	Concentrations (μg/plate)	2.5	2.5	60	2.5	2.5
	Mean No. of colonies/plate (average of 3 ± SD)	792 ± 39	138 ± 9	158 ± 4	659 ± 20	161 ± 27
Table 2. Test results of experiment 2 (preincubation test)
With or without S9-Mix	Test substance concentration	Mean number of revertant colonies per plate					Test substance concentration	Mean number of revertant colonies per plate
	(μg/plate)	(average of 3 plates ± Standard deviation)					(μg/plate)	(average of 3 plates ± Standard deviation)
		TA 100	TA 1535	TA 98		TA 1537		E. coli WP2 uvrA
–	0	53 ± 2	11 ± 2	20 ± 3		7 ± 1	0	60 ± 6
–	3.3	53 ± 3	10 ± 3	19 ± 4		7 ± 1	33	56 ± 15
–	10	56 ± 8	11 ± 1	21 ± 4		7 ± 2	100	68 ± 6
–	33	57 ± 3	11 ± 2	21 ± 3		6 ± 1	333	50 ± 11P
–	100	50 ± 5	10 ± 2	19 ± 2		7 ± 3	1000	64 ± 3P
–	333	43 ± 5P	7 ± 1	14 ± 2P		5 ± 2P	2500	44 ± 9P
–	1000	8 ± 3P	3 ± 1	8 ± 2P		1 ± 1P	5000	23 ± 3P
Positive controls, –S9	Name	MNNG	MNNG	NOPD		AAC	Name	4-NQO
	Concentrations (μg/plate)	5	5	10		100	Concentrations (μg/plate)	5
	Mean No. of colonies/plate (average of 3 ± SD)	763 ± 33	757 ± 24	584 ± 23		324 ± 22	Mean No. of colonies/plate (average of 3 ± SD)	738 ± 34
+	0	72 ± 6	12 ± 2	24 ± 4		7 ± 2	0	63 ± 3
+	3.3	74 ± 8	11 ± 2	25 ± 3		6 ± 2	33	61 ± 8
+	10	71 ± 8	12 ± 2	25 ± 4		6 ± 1	100	71 ± 7
+	33	72 ± 6	10 ± 1	28 ± 3		6 ± 2	333	61 ± 8P
+	100	67 ± 6	11 ± 2	23 ± 1		6 ± 3	1000	57 ± 7P
+	333	61 ± 3P	9 ± 1P	18 ± 4P		5 ± 1P	2500	46 ± 4P
+	1000	34 ± 6P	4 ± 2P	8 ± 1P		3 ± 0P	5000	30 ± 2P
Positive controls, –S9	Name	2AA	2AA	2AA		2AA	Name	2AA
	Concentrations (μg/plate)	2.5	2.5	2.5		2.5	Concentrations (μg/plate)	60
	Mean No. of colonies/plate (average of 3 ± SD)	861 ± 55	172 ± 5	602 ± 39		142 ± 12	Mean No. of colonies/plate (average of 3 ± SD)	159 ± 5
P: precipitation
B: reduced backgrownd growth
2-AA: 2-aminoanthracene
MNNG: N-methyl-N'-nitro-N-nitrosoguanidine
NOPD: 4-nitro-o-phenylenediamine
AAC: 9-aminoacridine
4-NQO: 4-nitroquinoline-N-oxide

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative