tert-butyl peroxypivalate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 1978

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods 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 402 (Acute Dermal Toxicity)

Deviations:

not specified

Principles of method if other than guideline:

5 doses were applied once only to the backs of rabbits for 24 hours and were observed the following 14 days.

GLP compliance:

no

Test type:

standard acute 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:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: H.A.R.E. Rabbits for Research, Hewitt, New Jersey
- Weight at study initiation: 2300 to 2805 g
- Housing: individually in hanging wire-mesh cages
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 12 days

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- % coverage: 20 - 30% of body surface
- Type of wrap if used: gauze banding

REMOVAL OF TEST SUBSTANCE
- Washing: tepid tap water
- Time after start of exposure: 24 hours

Duration of exposure:

24 hours

Doses:

1250; 2500; 5000; 10000 and 20000 mg/kg bw

No. of animals per sex per dose:

2 animals per sex per dose

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: 24 hours and daily for 14 days
- Frequency of weighing: prior to test material administration and on day 7 and 14
- Necropsy of died animals performed: yes

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 500 mg/kg bw

Based on:

test mat.

95% CL:

> 1 301 - < 4 806

Mortality:

1250 mg/kg bw: 1/4
2500 mg/kg bw: 1/4
5000 mg/kg bw: 4/4
10000 mg/kg bw: 4/4
20000 mg/kg bw : 4/4

Clinical signs:

other: Animals exposed up to 2500 mg/kg bw showed dermal irritations like moderate to marked erythema, edema, desquamation and necrosis, which were not reversible until day 14.

Gross pathology:

The animals died during the test exposed to doses higher than 5000 mg/ kg bw showed dermal irritation and ulceration and hyperemia of mucose of the stomach and discoloration of the liver. Males were more sensitive to the test item than females.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute dermal toxicity study with TBPPI in rabbits a LD50 value of 2500 mg/kg bw was determined.

Executive summary:

Twenty male and twenty female New Zealand White rabbits were used for an acute dermal toxicity study with TBPPI. The rabbits were divided into five groups of 2 male and 2 female rabbits each. The hair was removed from the back of each rabbit (20 -30% of the body surface) with an electric clipper. The test material was applied once only to the backs of the rabbits at the following dosage levels: 1250; 2500; 5000; 10000 and 20000 mg/ kg bw. Following dosing, the application sites were wrapped with gauze bandaging and overwrapped with Saran Wrap. 24 hours following application, the bandages were removed and the test sites were washed with tepid tap water. The rabbits were observed at 24 hours and daily thereafter for a total of 14 days for pharmacotoxic signs, mortality and dermal irritation. Body weights were recorded immediately prior to the test material administration and at 7 and 14 days of the observation period. All rabbits which died on study were subjected to gross necropsy examination.

All animals exposed to 5000 mg/kg bw and higher died during the testing period. One female and one male rabbit died in the lowest and the 2500 mg/kg bw dose level respectivly. In all surviving animals moderate to marked dermal irritation and necrosis occured and were not reversible until 14 days. Necropsy of died animals showed ulceration and hyperemia of the mucosa of the stomach and discoloration of the liver. No adverse effects on body weights of surviving animals could be observed.

The acute dermal LD50 values were 2500 mg/kg bw in males and females and the 95th confidence limits were 1250 - 5000 mg/kg bw in males and 625 - 10000 mg/kg bw in females.