tert-butyl peroxypivalate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1978

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1978

Report date:

1978

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

not specified

Principles of method if other than guideline:

Rats were exposed to a vapour atmosphere of the test item in an acute inhalation toxicity study.

GLP compliance:

no

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

tert-butyl peroxypivalate

EC Number:

213-147-2

EC Name:

tert-butyl peroxypivalate

Cas Number:

927-07-1

Molecular formula:

C9H18O3

IUPAC Name:

tert-butyl 2,2-dimethylpropaneperoxoate

additive 1

Reference substance name:

2,2,4,6,6-pentamethylheptane

EC Number:

236-757-0

EC Name:

2,2,4,6,6-pentamethylheptane

Cas Number:

13475-82-6

Molecular formula:

C12H26

IUPAC Name:

isododecane

Test material form:

liquid

Test animals

Species:

rat

Strain:

other: Charles River CD

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: male: 216 - 292 grams and female: 209 - 286 grams
- Housing: individually in compartmented wire-mesh exposure cages
- Diet: purina laboratory chow ad libitum
- Water: water ad libitum
- Acclimation period: at least week

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: a FMI Lab pump or a Harvard infusion pump
- Exposure chamber volume: 160 L
- Source and rate of air: 8 L/min

TEST ATMOSPHERE
- Brief description of analytical method used: The invidual concentratins of the compound in the chamber atmosphere were calculated from the ratio of the rate of liquid dissemination to the rate of total chamber airflow.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

2.0, 4.2, 8.3, 17.1 mg/L

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Individual body weights were recorded prior to the 4 hour exposure and at 24 and 48 hours in order to detect any latent effects following the exposure.
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

7.79 mg/L air (analytical)

Based on:

test mat.

95% CL:

5.89 - 10.28

Exp. duration:

4 h

Effect levels 2

Sex:

male

Dose descriptor:

LC50

Effect level:

5.07 mg/L air (analytical)

Based on:

test mat.

95% CL:

3.81 - 6.75

Exp. duration:

4 h

Effect levels 3

Sex:

female

Dose descriptor:

LC50

Effect level:

> 8.3 - < 17.1 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: by inspection only as data were not suitable for calculation

Mortality:

At the concentration of 2.0 mg/L, no mortality was observed. At the concentration of 4.2 mg/L, one male rat died. At the concentration of 8.3 mg/L, five male rats died. At the concentration of 17.1 mg/L, all animals died.

Clinical signs:

other: Slight to marked dyspnea was observed in all groups of rats at the concentrations above 2.0 mg/L.

Body weight:

All rats lost weight following the exposures.

Gross pathology:

Necropsy of the dead rats revealed reddened lungs with dark red patches and discoloration of the liver.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The 4 hours LC50 was calculated to be 7.79 mg/l with 95 % confidence limits of 5.89 and 10.28 mg/L (aerosol exposure).

Executive summary:

Tert-butyl peroxypivalate was tested in an acute inhalation toxicity study. Four groups of 5 male and 5 female rats were exposed to an aerosol atmosphere of tert-butyl peroxypivalate. The four "metered" concentrations were 17.1, 8.3, 4.2, 2.0 mg/L respectively. Slight to marked dyspnea and deaths were observed in all groups of rats at concentrations above 2.0 mg/L. All rats lost weight following the exposures. Necropsy of the dead rats revealed reddened lungs with dark red patches and discoloration of the liver. The 4 hours LC50 was calculated to be 7.79 mg/l with 95 % confidence limits of 5.89 and 10.28 mg/L.