tert-butyl peroxyisobutyrate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995-08-24 until 1995-09-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

1987

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

tert-butyl peroxyisobutyrate

EC Number:

203-650-5

EC Name:

tert-butyl peroxyisobutyrate

Cas Number:

109-13-7

Molecular formula:

C8H16O3

IUPAC Name:

tert-butyl 2-methylpropaneperoxoate

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:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Iffa Credo, 69210 L'Arbresle, France
- Age at study initiation: 6 weeks old
- Weight at study initiation: mean body weight of 184 ± 5 g for the males and 136 ± 4 g for the females
- Fasting period before study: 1 day
- Housing: The animals were housed individually in polystyrene cages
- Diet: A04 C pelleted diet (U.A.R., 91360 Villemoisson-sur-Orge, France)
- Water: drinking water filtered by a F.G. Millipore membrane (0.22 micron) was provided ad libitum.
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 21 ± 2°C
- Humidity: 30 to 70 %
- Air changes: about 12 cycles/hour of filtered, non-recycled air
- Photoperiod: 12 h/12 h

IN-LIFE DATES: 1995-08-24 to 1995-09-07

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

VEHICLE
- The test substance was administered in its original form taking into consideration that its density was 0.86. The volume administered to each animal was adjusted according to body weight determined on the day of treatment.

Doses:

2000 mg/kg in active material (i.e. corresponding to 2642 mg/kg in finished product)

No. of animals per sex per dose:

5 rats per sex

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observation of the animals was made at least once a day. The animals were weighed individually just before administration of the test substance on day 1 and then on days 8 and 15
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, macroscopic examination

Statistics:

No

Results and discussion

Preliminary study:

No

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

act. ingr.

Mortality:

Two out of five females were found dead on day 2 or 3.

Clinical signs:

other: In the males, sedation was observed one hour after treatment, and then piloerection and hypoactivity which persisted for four hours. Thereafter, no clinical signs were noted. In the females, sedation was noted one hour after treatment, in addition to pilo

Gross pathology:

Macroscopic examination of the main organs of the animals demonstrated no apparent abnormalities.

Other findings:

None

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the study LD50 of > 2000 mg/kg was determined.

Executive summary:

The test substance, tert-butyl peroxyiisobutyrate (TBPIB) 75.7 % in hydrocarbon was administered by oral route to one group of ten fasted Sprague-Dawley rats (five males and five females). according to OECD 401 and EU method B1 guidelines. The test substance was administered in its original form, by gavage, at a dose of 2000 mg/kg in active material. Clinical signs, mortality and body weight gain were checked for a period of 14 days following the single administration of the test substance. All animals were subjected to necropsy.

The body weight gain of the animals was not affected by treatment with the test substance. Two out of five females were found dead on day 2 or 3. In the males, sedation was observed one hour after treatment, and then piloerection and hypoactivity which persisted for four hours. Thereafter, no clinical signs were noted. In the females, sedation was noted one hour after treatment, in addition to piloerection and dyspnea two hours after; then, hypoactivity and piloerection were noted after four hours. Thereafter, no clinical signs were noted, except coma in one out of five females on day 2 prior to death on day 3. No abnormalities were observed at necropsy.

Under the study experimental conditions, the oral LD50 of the test substance was higher than 2000 mg/kg in rats.