1-ethoxypropan-2-ol

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1984

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Comparable to a guideline study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method B.2 (Acute Toxicity (Inhalation))

GLP compliance:

no

Test type:

fixed concentration procedure

Test material

Test material information

Constituent 1

Reference substance name:

1-ethoxypropan-2-ol

EC Number:

216-374-5

EC Name:

1-ethoxypropan-2-ol

Cas Number:

1569-02-4

Molecular formula:

C5H12O2

IUPAC Name:

1-ethoxypropan-2-ol

Details on test material:

- Name of test material (as cited in study report): Ethoxypropanol
- Physical state: Liquid
- Analytical purity: 91.1%
- Impurities (identity and concentrations):
8.0% 2-ethoxy-1-propanol
0.7% 1-methoxy-2-propanol
0.1% 2-methoxy-1-propanol
0.04% 1-(2-propenyloxy)-2-propanol
- Purity test date: 6 June 1983
- Lot/batch No.: Batch No. 96 from BP Chemie, Lavera
- Storage condition of test material: At room temperature

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River UK Ltd.
- Weight at study initiation: 135 - 179 g when received
- Housing: Except during exposure, animals were housed in groups of three in polypropylene cages with stainless steel grid tops and floors.-
- Diet: Labsure PRD, C Hill Group Ltd.
- Water: Tap water replaced daily
- Acclimation period: 11 days

ENVIRONMENTAL CONDITIONS
- Temperature: 21 – 28 degrees C
- Humidity: 40 – 61 % relative humidity
- Photoperiod: 12 hour dark: 12 hour light cycle

IN-LIFE DATES: From: June 2, 1983 To: June 28, 1983

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

nose only

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Using a peristaltic pump, ethoxypropanol was metered into a stainless steel tube so that the liquid dripped on a column of glass beads warmed to 125 degrees C and through which air flowed. The vapours emitted from the column were diluted in chilled, humidified air, thoroughly mixed and administered to the rats.
- Method of holding animals in test chamber: Individual glass exposure tubes.
- Temperature, humidity, pressure in air chamber: Mean temperature = 24 degrees C (test animals); 22 degrees C (control animals)
Mean relative humidity = 61 % (test animals); 57 % (control animals)

TEST ATMOSPHERE
- Brief description of analytical method used: Samples of the vapour atmosphere were taken from the exposure module using a 5 ml gas tight syringe and injected into the nitrogen input stream of a gas chromatograph with a Tenax packed column at 150 degrees C and a flame ionization detector.

Analytical verification of test atmosphere concentrations:

yes

Remarks:

no further data

Duration of exposure:

4 h

Concentrations:

The mean vapour concentration was 9.59 g/m3 (2213 ppm).

No. of animals per sex per dose:

6 males and 6 females.

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical signs at the end of exposure. Body weights were recorded daily following exposure.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: Respiration rates and patterns were recorded using an optical technique every half hour during exposure.
Organ weights (lungs, liver, and testes).Tissues fixed in neutral buffered formalin (testes, grossly abnormal tissues).

Statistics:

Differences in organ weights and respiration rates were analyzed using Student’s ‘t’ test.

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LC0

Effect level:

> 9.59 mg/L air

Exp. duration:

4 h

Remarks on result:

other: maximum achievable concentration

Effect levels 2

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 9.59 mg/L air

Exp. duration:

4 h

Remarks on result:

other: maximum achievable concentration

Mortality:

There were no deaths during the study.

Clinical signs:

other: Animal movements were uncoordinated when removed from the exposure tubes. Three animals appeared sedated. All animals recovered within approximately 75 minutes after being returned to fresh air.

Body weight:

Exposure to ethoxypropanol vapour had no effect on body weight gain.

Gross pathology:

There were no findings attributable to exposure.

Other findings:

- Organ weights: Lung, liver and testes weights were not affected by treatment.
- Other observations: Mean respiration rates decreased to levels statistically significantly lower than control animals during the first 30 minutes of exposure.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Based on these results, the LC0 (4-hour) for ethoxypropanol vapour is greater than 9.59 mg/l.

Executive summary:

In a GLP acute nose-only inhalation toxicity study in rats, a single 4-hour exposure to ethoxypropanol at a concentration of 9.59 mg/l did not produce lethality.  This was the maximum practically achievable vapour concentration under ambient dynamic conditions. A reduction in respiratory rate occurred during exposure, and some animals appeared sedated upon removal from exposure, but recovered within 75 minutes.  No effect on body weight gain and no gross pathological changes were observed.