2-(2-butoxyethoxy)ethyl acetate

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in mammalian cells

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

Study period:

1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

A published study containing sufficient details to regard it as reliable for use in hazard assessment. Only basic experimental detail provided in publication but sufficient to judge reliability. Read across justification is contained in overall remarks section.

Data source

Reference

Reference Type:

publication

Title:

Toxicology of diethylene glycol monobutyl ether 3. Genotoxicity evaluation in an in vitro gene mutation assay and an in vivo cytogenic test

Author:

Gollapudi, B.B., et al. (1993).

Year:

1993

Bibliographic source:

J. Am. Coll. Toxicol. 12(2), 155-59

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

Principles of method if other than guideline:

According to the method of O'Neill (Mut Res, 45, 91-101 and Mut Res, 45, 103-9 - both 1977)

GLP compliance:

not specified

Remarks:

reported as a GLP compliant study

Type of assay:

mammalian cell gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-butoxyethoxy)ethanol

EC Number:

203-961-6

EC Name:

2-(2-butoxyethoxy)ethanol

Cas Number:

112-34-5

Molecular formula:

C8H18O3

IUPAC Name:

2-(2-butoxyethoxy)ethanol

Details on test material:

- Name of test material (as cited in study report): diethylene glycol monobutyl ether (DGBE)
- Analytical purity: 99.51%
- Impurities (identity and concentrations): peroxides 43ppm
- Lot/batch No.: QP-870323-35-S1

Method

Target gene:

HGPRT locus located on the mammalian X chromosome.

Species / strain

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Metabolic activation system:

Aroclor induced rat liver S9

Test concentrations with justification for top dose:

1000 to 5000 µg/ml in steps of 1000

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: culture medium

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

Remarks:

Culture medium was used to dissolve the test compound

True negative controls:

no

Positive controls:

yes

Positive control substance:

ethylmethanesulphonate

Remarks:

Migrated to IUCLID6: without metabolic activation

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 20-methylcholanthracene. with metabolic activation. DMSO solvent used.

Details on test system and experimental conditions:

METHOD OF APPLICATION: in selection medium Ham's F-12 without hypoxanthine and with 10µM -thioguanine.

DURATION
- Exposure duration: 4hrs at 37C.
- Expression time (cells in growth medium): 8 days prior to plating and mutant selection.

NUMBER OF REPLICATIONS: 2

DETERMINATION OF CYTOTOXICITY
- The cytotoxicity of the test material was assessed by determining the ability of the treated cells to form colonies. The cultures (3 cultures/dose level) were treated with the test chemical or the solvent in the presence and absence of S9 factor. After termination of treatment, cultures were incubated for 7 days to allow colony formation, fixed with methanol and stained with crystal violet. The numberof colonies/dish was counted and the mean colonies/dish/treatment wereexpressed relative to the negative control value.

Evaluation criteria:

no further data

Statistics:

Pairwise comparisons with control (p<0.01, one sided) and by liner and quadratic trend analysis (p<0.25, one sided)

Results and discussion

Test results

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Remarks:

No effects up to the maximum recommended dose for this assay of 5000 µg/ml

Vehicle controls validity:

not specified

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

Table 1: Results

		Assay 1		Assay 1
Treatment		RCS^a[%]	mutation frequency^b	RCS^a[%]	mutation frequency^b
µg/mL DGBE	S9
Negative control	-	100	1.4	100	0
	+	100	0	100	0
1000	-	95.1	7.2	106	0
	+	116.8	3.3	107.3	706
2000	-	94.7	3.3	102.7	2.4
	+	98.7	0	102.8	1.3
3000	-	93.9	2.9	112.2	5.1
	+	114.3	0	98.9	13.9^c
4000	-	86.6	0	100	0
	+	113.9	0	98	0
5000	-	96.7	0	106.4	0
	+	104	0	102.6	5.3
positive control	-	83.8	557.7^c	87.7	299.4^c
	+	94.6	359.2^c	98.9	325.4^c

a: Relative cell survival = colonies per dish in the treated/colonies per dish in the negative control

b: TG mutants per 10000000 cloable cells

c: significantly (p<= 0.01) different from the negative control

In one of the replicate assays, the 3000 µg/ml dose produced a mutation frequency significantly greater than the concurrent control. No mutations were seen in the current control and if historical values were used for comparison, no significant difference was seen. This result was therefore attributed to a statistical abberation and not treatment related.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with metabolic activation
negative without metabolic activation

2-(2-butoxyethoxy)ethanol is not cytotoxic in this test system up to the maximum recommended test concentration of 5 mg/ml and does not cause forward mutation up to similar doses.

Executive summary:

In an in vitro forward gene mutation assay at the HGPRT locus of CHO cells, 2 -(2 -butoxyethoxy)ethanol did not elicit a positive response when tested up to the maximum recommended dose of 5000ul/ml with and without S9 metabolic activation.