2-(2-ethoxyethoxy)ethanol

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

Study period:

From 18 November 1998 to 12 February 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Study conducted according to guideline protocol

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OTS 798.5265 (The Salmonella typhimurium Bacterial Reverse Mutation Test)

Deviations:

no

Principles of method if other than guideline:

not applicable

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-ethoxyethoxy)ethanol

EC Number:

203-919-7

EC Name:

2-(2-ethoxyethoxy)ethanol

Cas Number:

111-90-0

Molecular formula:

C6H14O3

IUPAC Name:

2-(2-ethoxyethoxy)ethan-1-ol

Details on test material:

- Name of test material (as cited in study report): Transcutol P
- Physical state: Colourless liquid; Density 0.98
- Analytical purity: 100%
- Lot/batch No.: 9833703
- Storage condition of test material: Room temperature

Method

Target gene:

Histidine

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:

S. typhimurium TA 102

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

S9 from liver of rats treated with a mixture of phenobarbital and methylcholantrene

Test concentrations with justification for top dose:

Preliminary experiment and Experiment 1: 52, 164, 512, 1600, 5000 ug/plate
Experiment 2: 492, 878, 1568, 2800 and 5000 ug/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: water (supplier Biosedra, batch number LR82159, LR 82414 and LR 82274)
- Justification for choice of solvent/vehicle: the test article was soluble in water at 50mg/ml

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

water

Negative solvent / vehicle controls:

yes

Remarks:

water

True negative controls:

yes

Remarks:

untreated

Positive controls:

yes

Positive control substance:

sodium azide

Controls 2

Positive controls:

yes

Positive control substance:

9-aminoacridine

Controls 3

Positive control substance:

2-nitrofluorene

Remarks:

Migrated to IUCLID6: 2-nitrofluorene, t-butyl hydroperoxide, 2-aminoanthracene

Controls 4

Positive controls:

yes

Positive control substance:

other: t-butyl hydroperoxide, 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: For each experiment, the test strain cultures were grown in nutrient broth for 6-16 hrs at 37C.
- Exposure duration: minimum 48hrs at 37C

NUMBER OF REPLICATIONS: triplicates

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth - reduction in bacterial lawn and/or reduction in the number of revertants with evidnece of a dose relationship

Evaluation criteria:

Based on the validity of the study (mean negative control counts within range of historical data; positive controls inducing clear increases in revertant numbers; and no more than 5% of the plates in the assay lost through contamination or any other unforeseen event), statistically significant (p<=0.05), dose related or reproducible increases in the number of revertant cells with evidence of a biological effect.

Statistics:

Dunnett's t test

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 4

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

RANGE-FINDING/SCREENING STUDIES: The mean numbers of revertant colonies on negative control plates were within the range of historical negative control values and the revertant frequency was significantly increased on positive control plates. No plates were lost through contamination or any other unforeseen event. All the criteria for a valid preliminary study were met. In the absence of cytotoxicity these results were used as the actual mutagenicity data for TA100 for Experiment 1.

COMPARISON WITH HISTORICAL CONTROL DATA: within range of historical negative control values

ADDITIONAL INFORMATION ON CYTOTOXICITY: no cytotoxicity was observed

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Scoring of mutants

1) Experiment 1:

Without metabolic activation: when compared to the negative (vehicle) control value, a statistically significant increase in the number of revertants (1.43 -fold the value obtained with the negative control) was noted in the strain TA98 at 5000ug/plate. No statistically significant increases in the number of revertants were noted in the other strains. All the man values were in the range of historical negative control data.

With metabolic activation: When compared to the negative (vehicle) control value, no statistically significant increases in the number of revertants were noted in the 5 strains used. All the mean values were in the range of historical negative control data.

2) Experiment 2:

Without metabolic activation: when compared to the negative (vehicle) control value, no statistically significant increases in the number of revertants were noted in the 5 strains used. All the mean values were in the range of historical negative control data.

With metabolic activation: when compared to the negative (vehicle) control value, a statistically significant increase in the number of revertants (1.14 -fold the value obtained with the negative control) was noted in the strain TA102 at 1568ug/plate. No statistically significant increases in the number of revertants were noted in the other strains. all the mean values were in the range of historical negative control data.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

The test substance is not considered to be mutagenic under the conditions of this Ames study.

Executive summary:

The mutagenicity of 2 -(2 -ethoxyethoxy)ethanol was studied in Salmonella typhimurium strains TA98, TA100, TA102, TA1535, and TA1537. Two independent experiments were conducted at 52, 162, 512, 1600 and 5000ug/plate, and 492, 878, 1568, 2800 and 5000ug/plate, respectively, with and without S9 metabolic activation systems. No signs of cytotoxicity and no precipitate were observed up to the highest dose tested, and the test article did not induce any biological relevant or statistically significant increases in the number of revertants in any of the 5 test strains, either with or without metabolic activation. Therefore, the test substance is considered non-mutagenic under the conditions of this study.