1,2-bis(2-methoxyethoxy)ethane

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:

26 Nov - 23 Jan 1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

E. coli WP2 uvrA not tested

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

1,2-bis(2-methoxyethoxy)ethane

EC Number:

203-977-3

EC Name:

1,2-bis(2-methoxyethoxy)ethane

Cas Number:

112-49-2

Molecular formula:

C8H18O4

IUPAC Name:

2,5,8,11-tetraoxadodecane

Constituent 2

Reference substance name:

Triglyme

IUPAC Name:

Triglyme

Constituent 3

Reference substance name:

Triethylene glycol dimethyl ether

IUPAC Name:

Triethylene glycol dimethyl ether

Details on test material:

Purity: > 99.9%
colorless liquid

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1538

Species / strain 2

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Test concentrations with justification for top dose:

Study I: 4, 20, 100, 500, 2500, 10000 µg/plate
Study II: 4, 20, 100, 500, 2500, 5000 µg/plate

Vehicle / solvent:

distilled water

Details on test system and experimental conditions:

Toxicity experiments and dose range finding:
The first experiment (I) was performed with all tester strains using three plates per dose to get information on mutagenicity and toxicity for calculation of an approriate dose range. A reduced rate of spontaneously occuring colonies as well as visible thinning of the bacterial lawn were used as indicator for toxicity. Thinning of the bacterial lawn was controlled microscopically.
In combination with the second experiment, toxicity testing was performed as follows:
0.1 mL of the different dilutions of the test compound were thoroughly mixed with 0.1 mL of 10exp(-6) dilution of the overnight culture of TA100 and plate with Histidine and Biotin rich top agar (3 plates per dose). The solvent control is compared with the number of colonies per plate in the presence of the tst compound. Results are given as a ration of these values (=surviving fraction).

Mutagenicity test:
Top agar is prepared for the Salmonella strains by mixing 100 mL Agar (0.6 % Agar, 0.5% NaCl) with 10 mL of a 0.5 mL Histidine-biotin solution. The following ingredients are added to 2 mL of molten top agar at 46°C:
0.1 mL of an overnight nutrient broth culture of the bacterial tester strain, 0.1 mL test compound solution, 0.5 mL S9 mix or buffer.
After mixing, the liquid is pooured into a Petridish with minimal Agar (1.2 % Agar, Vogel-Bonner E medium with 2% Glucose). After incubation for approx. 48 hours at 37°C in the dark, colonies are counted. Two independent exeriments were performed.

Positive controls:
Positive control plates were included for each strain. the following substances were used as positive controls:

a) without S9 mix
Sodium azide: TA100, TA 1535
9-Aminocridine: TA1537
2-Nitrofluorene: TA98, TA1538

b) with S9 mix
Benzo[a]pyrene: TA98, TA100, TA1535, TA1537, TA1538
2-Aminoanthracene: TA98, TA100, TA1535, TA1537, TA1538

Evaluation criteria:

No data

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 4

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 5

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Controls:
Control plates (background control and positive controls) gave the expected number of colonies.

Toxcity test:
The test compound was tested at doses of 4 to 10000 µg/plate and proved to be not toxic to the bacterial strains. For mutagenicity testing 5000 µg/plate was chosen as the highest dose in the second experiment.

Mutagenicity test:
Triethylene glycol dimethyl ether did not cause a significant increase in the number of revertant colonies with any of the tester strains either in the absence or presence of S9 mix. No dose dependent effect was obtained.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

AmesTriethylene glycol dimethyl ether

 

Table 1: Summary of mean number of revertants (study I, mean of at 3 plates) in Salmonella typhimurium with and without metabolic activation (negative and positive controls)

Concentration	TA 98		TA 100			TA1535					TA 1537
[µg/plate]	- S9 mix	+ S9 mix	- S9 mix		+ S9 mix	- S9 mix		+ S9 mix			- S9 mix	+ S9 mix
0	22	28	189		201	13		14			8	7
4	25	31	207		193	11		7			5	7
20	23	27	194		217	12		8			8	6
100	22	24	212		205	7		10			7	7
500	20	27	212		206	11		10			3	7
2500 10000	23 25	27 28	230 219		210 214	11 17		9 7			8 8	5 9
Positive:
Sodium Azide			534			368
9-Aminoacridine 2-Nitrofluorene	635										135
2-Aminoathracene		585			841			122				120
Benzo[a]pyrene		731			1326			20				131
Concentration	TA 1538
[µL/plate]	- S9 mix	+ S9 mix
0	14	12
4	13	12
20	10	18
100	13	22
500	18	20
2500 10000	13 14	15 16
Positive:
Sodium Azide
9-Aminoacridine 2-Nitrofluorene	725
2-Aminoathracene		362
Benzo[a]pyrene		199

 

 

Table 2: Summary of mean number of revertants (study II, mean of at 3 plates) in Salmonella typhimurium with and without metabolic activation (negative and positive controls)

Concentration	TA 98		TA 100			TA1535					TA 1537
[µg/plate]	- S9 mix	+ S9 mix	- S9 mix		+ S9 mix	- S9 mix		+ S9 mix			- S9 mix	+ S9 mix
0	19	29	191		195	12		9			11	10
4	21	28	185		205	10		14			13	11
20	19	29	181		193	11		11			12	9
100	19	30	186		206	9		9			12	10
500	17	32	195		203	9		10			9	13
2500 5000	16 22	33 29	190 193		212 211	10 9		7 10			11 9	11 9
Positive:
Sodium Azide			550			374
9-Aminoacridine 2-Nitrofluorene	739										106
2-Aminoathracene		598			1006			143				149
Benzo[a]pyrene		712			1508			31				156
Concentration	TA 1538
[µL/plate]	- S9 mix	+ S9 mix
0	16	19
4	14	15
20	18	20
100	16	23
500	14	12
2500 5000	11 14	16 15
Positive:
Sodium Azide
9-Aminoacridine 2-Nitrofluorene	806
2-Aminoathracene		593
Benzo[a]pyrene		247

 

Applicant's summary and conclusion

Conclusions:

Triethylene glycol dimethyl ether is not mutagenic in bacterial reverse mutation assay.

Executive summary:

Triethylene glycol dimethyl ether was tested for mutagenicity with the strains TA1538, TA1537, TA1535, TA100 and TA98 of Salmonella thyphimurium.

The mutagenicity study was conducted in the absence and presence of a metabolising system derived from rat liver homogenate. A concentration of 4 to 10000 µg Tirethylene glycol dimethyl ether/plate was used.

Control plates without mutagen did not show an increase in the number of revertant colonies. All positive control compounds gave the expected increase in the number of revertant colonies.

Triethylene glycol dimethyl ether did not show an increase in the number of revertants in any of the bacterial strains in the presence as well as in the absence of metabolic activation.

Therefore, it can be stated that Triethylene glycol dimethyl ether is not mutagenic in these bacterial test systems either with or without metabolic activation.