4-methylpentan-2-ol

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1981

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented, according to accepted guidelines

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

no

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-methylpentan-2-ol

EC Number:

203-551-7

EC Name:

4-methylpentan-2-ol

Cas Number:

108-11-2

Molecular formula:

C6H14O

IUPAC Name:

4-methylpentan-2-ol

Details on test material:

- Name of test material (as cited in study report): Methyl Isobutyl Carbinol
- Analytical purity: Not reported
- Lot/batch No.: Indent No. 9200/9360
- Stability under test conditions: Not reported
- Storage condition of test material: Not reported

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Shell Toxicology Laboratory (Tunstall) Unit
- Age at study initiation: 11 weeks of age
- Weight at study initiation: 264 to 310 g (males) and 179 to 210 g (females)
- Housing: Wire mesh cages with stainless steel wire mesh floor and top. Individually housed
- Diet (e.g. ad libitum): Ad libitum (PRD, Labsure Animal Foods Ltd.)
- Water (e.g. ad libitum): Ad libitum (filtered but untreated water from public supply)
- Acclimation period: Not reported


ENVIRONMENTAL CONDITIONS
- Temperature (°C): Approximately 20 ºC
- Humidity (%): Approximately 55%
- Air changes (per hr): Not reported
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

other: Type of exposure not specifically stated, but assumed to be whole body

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: 7 litre tubular glass chambers
- Exposure chamber volume: 7 litres
- The test atmosphere was generated by means of a wick-type saturator and was supplied to two identical glass inhalation chambers each of volume 7 litres. The test atmosphere was supplied to each chamber at a minimum flow rate of 8 litres/minute.

TEST ATMOSPHERE
- Brief description of analytical method used: Measured continuously throughout the exposure by means of a total hydrocarbon analyser fitted with a flame ionisation detector.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

10000 or 16000 mg/m3 (nominal).

No. of animals per sex per dose:

5/sex/dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observed for toxic signs continuously for the first 30 minutes and thereafter at 15 minute intervals throughout the exposure. Over the following 14 days, the animals were observed twice daily. Body weights were recorded initially and after 7 and 14 days.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weights, and gross post mortem examination.

Statistics:

None.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 16 000 mg/m³ air (nominal)

Exp. duration:

4 h

Mortality:

One female rat exposed to 16000 mg/m3 died at termination of exposure.

Clinical signs:

other: All exposed animals were anaesthetised within the first hour of exposure. All but one of those animals exposed to the larger concentration of 16000 mg/m3 regained consciousness within 2 h after completion of exposure. One female rat did not regain consc

Body weight:

Body weight gains over the experimental period were normal.

Gross pathology:

Nothing reported.

Other findings:

Nothing reported.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: other: CLP (EC 1272/2008)

Conclusions:

The 4h acute inhalation LC50 of MIBC in rats is > 16000 mg/m3.

Executive summary:

The potential acute inhalation toxicity of methyl i-butylcarbinol was assessed in Wistar rats in a study similar in methodology to OECD gudelines for the Testing of Chemicals No. 403. Groups of 5 male and 5 female Wistar rats were exposed to 10000 or 16000 mg/m3 for 4 hours (whole-body exposure). The test atmosphere was generated using a wick-type saturator and was supplied to two identical glass inhalation chambers. The test atmosphere was passed through each chamber at a volume of 7 liters. The animals were observed for toxic signs continuously for the first 30 minutes and thereafter at 15 minute intervals throughout the exposure period. Over the following 14 days, animals were observed twice daily. Body weights were recorded initially and after 7 and 14 days. One female animal exposed to 16000 mg/m3 died at termination of exposure. All animals were anaesthetized within the first hour of exposure and all regained consciousness within half an hour in the 10000 mg/m3 group and all but one animal (a female that died) regained consciousness within 2 hours in the 16000 mg/m3 group. Body weights were normal and there were no signs of toxicity over the 14-day observation period in surviving animals. The inhalation LC50 of methyl i-butylcarbinol was determined to be greater than 16000 mg/m3.