Ethanol, 2-ethoxy-, manufacture of, by-products from

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:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Scientifically reliable study. Well reported

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

not specified

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-(2-methoxyethoxy)ethoxy)ethanol

EC Number:

203-962-1

EC Name:

2-(2-(2-methoxyethoxy)ethoxy)ethanol

Cas Number:

112-35-6

Molecular formula:

C7H16O4

IUPAC Name:

2-[2-(2-methoxyethoxy)ethoxy]ethanol

Constituent 2

Reference substance name:

Methyltriglycol

IUPAC Name:

Methyltriglycol

Details on test material:

- Name of test material (as cited in study report): Methyltriglycol
- Molecular weight: 164
- Physical state: colourless, clear liquid
- Analytical purity: >95%

Method

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

Species / strain 3

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254

Test concentrations with justification for top dose:

4 to 10,000 microgram/plate. 5,000 microgram/plate was chosen as the highest dose in the second experiment.

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

True negative controls:

no

Positive controls:

yes

Remarks:

Without metabolic activation

Positive control substance:

other: NA-azide (TA 100, TA 1535), 9-aminoacridine (TA 1537), 2-Nitroflourene (TA 98, TA 1538), N-Metnyl-N-nitro-N-nitrosoguanidine (WP2uvrA).

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

True negative controls:

no

Positive controls:

yes

Remarks:

With metabolic activation

Positive control substance:

other: Benzo[a]pyrene: TA 98, TA 100, TA 1535, TA 1537, TA 1538. WP2uvrA, 2-Aminoanthracene: TA 98, TA 100, TA 1535, TA 1537, TA 1538, WP2uvrA

Details on test system and experimental conditions:

METHOD OF APPLICATION: Top agar is prepared for the Salmonella strains by mixing 100 ml agar (0.6 % agar, 0.5 ~ NaCl) with 10 m1 of a 0.5 % histidine-biotin solution. With E. coli histidine is replaced by tryptophan (2.5 ml, 0.5 mM). The following ingredients are added (in order) to 2 ml of molten top agar at 45 degrees C:
- 0.1 ml of an overnight nutrient broth culture of the bacterial tester strain
- 0.1 ml test compound solution
- 0.5 ml S-9 Mix (if required) or buffer
After mixing, the liquid is poured into a petridish with minimal agar (1.5 % agar, Vogel-Bonner E medium With 2 % glucose).


DURATION
- Incubation period: 46 to 72h @ 37 degrees C in the dark. Colonies (his+ revertants) are counted .

Results and discussion

Test results

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not examined

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

The test compound 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 5-9 Mix. No dose dependent effect was obtained.

Surviving colonies per plate – experiment one

Without metabolic activation

ug/plate	TA100	TA1535	TA1537	TA1538	TA98	WP2uvrA
0	200	15	10	14	22	62
4	226	19	11	12	26	65
20	217	20	12	13	24	63
100	211	18	8	16	25	67
500	206	15	8	18	25	62
2500	207	18	9	14	31	59
10000	209	21	12	17	26	67
+ve control	627	465	154	500	373	357
Sterility contr	0	0	0	0	0	0

 

With metabolic activation

ug/plate	TA100	TA1535	TA1537	TA1538	TA98	WP2uvrA
0	175	16	9	20	34	67
4	167	11	10	19	29	74
20	192	10	11	21	26	74
100	191	16	7	21	33	75
500	211	11	8	19	39	64
2500	228	17	13	22	37	72
10000	205	17	8	20	43	72
2-aminoanthr	668	177	97	436	426	233
Benzo[a]pyr.	614	20	144	192	648	92
S9 mix	0	0	0	0	0	0
Sterility contr	0	0	0	0	0	0

 

Surviving colonies per plate – experiment two

Without metabolic activation

ug/plate	TA100	TA1535	TA1537	TA1538	TA98	WP2uvrA
0	198	16	9	16	27	53
4	185	16	9	11	26	57
20	189	17	9	10	30	43
100	204	18	10	13	23	60
500	193	20	7	11	25	55
2500	215	13	12	18	28	61
5000	224	20	12	13	31	66
+ve control	622	398	157	533	392	380
Sterility contr	0	0	0	0	0	0

 

With metabolic activation

ug/plate	TA100	TA1535	TA1537	TA1538	TA98	WP2uvrA
0	208	14	8	19	29	70
4	212	12	11	17	31	48
20	210	13	9	13	30	54
100	209	13	10	22	33	51
500	201	12	9	18	30	57
2500	200	12	10	20	40	67
5000	208	13	10	19	31	70
2-aminoanthr	736	159	90	431	415	281
Benzo[a]pyr.	633	26	136	151	677	73
S9 mix	0	0	0	0	0	0
Sterility contr	0	0	0	0	0	0

 

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Methyltriglykol is not mutagenic in these bacterial test systems either with or without exogenous metabolic activation at tne dose levels investigated.

Executive summary:

In a bacterial reverse mutation (Ames) assay using the S. typhimurium strains TA 1535, TA 1537, TA1538, TA 98 and TA 100 plus the E coli strain WP2 uvrA, no mutagenic activity was observed either with our without metabolic activation up to the maximum tested dose of 10mg/plate for the substance methyl triglycol. This result can be considered representative by read across of the likely result that would be obtained with the closely related substance ethyl triglycol (2 -(2 -ethoxyethoxy)ethanol.