2-methoxyethanol

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Sufficiently well reported to regard as reliable contributor to data for this end point

Data source

Reference

Reference 1

Reference Type:

publication

Title:

The effects on the rat of single inhalation exposures to ethylene glycol monoalkyl ethers, in particular ethylene glycol monomethyl ether,

Author:

Samuels DM, Doe JE, Tinston DJ

Year:

1984

Bibliographic source:

Arch Toxicol, 7, p167-70

Reference 2

Reference Type:

publication

Title:

Further studies on the toxicology of the glycol ethers with emphasis on rapid screening and hazard assessment.

Author:

Doe JE

Year:

1884

Bibliographic source:

Env Hlth Persp, 57, 199-206

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The purpose of the study was to assess testes effects following acute exposure. However, the methodology used does provide acute lethality information.

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-methoxyethanol

EC Number:

203-713-7

EC Name:

2-methoxyethanol

Cas Number:

109-86-4

Molecular formula:

C3H8O2

IUPAC Name:

2-methoxyethanol

Details on test material:

Supplier: Merck
Purity: 99.5%

Test animals

Species:

rat

Strain:

other: Alderley Park (Alpk) albino

Sex:

male

Details on test animals or test system and environmental conditions:

8 week old pathogen free animals used. Animals acclimatized to whole body test chambers for 24 hours before transferring to holding cages for 13 days observation after exposure.

Administration / exposure

Route of administration:

inhalation: gas

Type of inhalation exposure:

whole body

Analytical verification of test atmosphere concentrations:

yes

Remarks:

Concentrations monitored using an infra-red analyzer.

Duration of exposure:

ca. 4

Concentrations:

150, 300, 625, 1250, 2500, 5000ppm. Top dose corresponded to saturated vapour pressure of 15.8mg/l.

No. of animals per sex per dose:

20 plus 40 control animals.

Control animals:

yes

Details on study design:

Body weights recorded on day -1, 6 and 13. Animals sacrificed on day 13 and sex organs examined

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LC0

Effect level:

> 15.8 mg/L air

Exp. duration:

4 h

Effect levels 2

Sex:

male

Dose descriptor:

other: NOAEC

Effect level:

ca. 0.95 mg/L air

Exp. duration:

4 h

Mortality:

There was no record of any deaths at any exposure concentration.

Gross pathology:

Dose related decrease in testes weight from 1250ppm upwards.

Other findings:

Testes weights were not affected at 650ppm but there was evidence of sperm damage (minimal degenerative changes), disordered spermatogenesis, tubular atrophy). The NOAEL from the study was 300ppm (0.95mg/l).

Any other information on results incl. tables

The results do not provide a true LC50 and as such are only of partial use for classification and labeling purposes, but they can be used to derive a NOAEL for risk assessment purposes with appropriate safety factors.

In the second study, disordered spermatogenesis was seen in exposed animals (both dose levels) which persisted until the end of the observation period on day 19.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

It can be concluded that the LC50 is greater than 5000ppm (15.8mg/l)

Executive summary:

In a study designed to assess testes effects following acute exposure, male rats were exposed to a number of concentrations of methoxyethanol in the range 150ppm up to saturated vapour pressure for a period of 4 hours. No deaths were observed at any concentration. However, the study did note adverse effects on the testes of animals exposed to 625ppm and above of methoxyethanol, producing a NOAEC of 300ppm. The study did not provide a true LC50 and as such the results are only of partial use for classification and labeling purposes, but they can be used to derive a NOAEL for risk assessment purposes with appropriate safety factors. It can also be concluded that the LC50 is greater than 5000ppm (15.8mg/l)

Results synopsis

LC0>15.8mg/l (4hrs exposure)

NOAEC=0.95mg/l (4hrs exposure, testes effects)