tert-pentyl peroxypivalate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Date: September 24, 1981

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Conducted in accordance with the regulations for Good Laboratory Practices as described by the FDA (21 CFR Part 58) and FDRL Standard Operating Procedures.

GLP compliance:

yes

Test type:

standard acute method

Test material

Test material information

Constituent 1

Reference substance name:

tert-pentyl peroxypivalate

EC Number:

249-530-6

EC Name:

tert-pentyl peroxypivalate

Cas Number:

29240-17-3

Molecular formula:

C10H20O3

IUPAC Name:

tert-pentyl peroxypivalate

additive 1

Reference substance name:

Hydrocarbons, C4, 1,3-butadiene-free, polymd., triisobutylene fraction, hydrogenated

EC Number:

297-629-8

EC Name:

Hydrocarbons, C4, 1,3-butadiene-free, polymd., triisobutylene fraction, hydrogenated

Cas Number:

93685-81-5

Molecular formula:

not applicable (a generic molecular formula cannot be provided for this specific UVCB substance)

IUPAC Name:

isododecane

Test material form:

liquid

Specific details on test material used for the study:

FDRL Test Article ID: 81-0558
Sponsor Test Article ID: TA-54M75; tert-amyl peroxypivalate 75% in odorless mineral spirit

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

Five male and 5 female adult New Zealand White rabbits, weighing between 2.0 and 4.0 kg, were purchased from H.A.R.E. - Rabbits for Research, Hewitt, N.J. for use in this-study. H.A.R.E. - Rabbits is a USDA approved supplier.
All animals were acclimated a minimum of 5 days. During this acclimation period, the rabbits were examined with respect to their general health to assure their suitability as test animals. The rabbits were housed individually
in wire mesh bottom cages. NIH Animal Feed A (certified) and water were provided ad libitum. Animals were identified by use of ear tags and cage cards.

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

The back and flanks of each rabbit were clipped free of fur with electrical clippers not more than 24 hours before study initiation. The clipped area constituted approximately 30 percent of the total body surface.
On the day of testing and just prior to the application of the test article, abrasion of the skin was performed on the exposure sites of 3 males and 2 female rabbits. The skin of the remaining 2 male and 3 female rabbits was left intact. Abrasions were made with the point of a 22 gauge disposable hypodermic needle. The abrasions were minor incisions through the stratum corneurn that were not sufficiently deep enough to disturb the derma or to produce bleeding.
The test article was administered under an occlusive binder at a level of 2.0 g/kg. The occlusive binder consisted of a layer of plastic wrap, a protective cloth and stockinette binder, all securely held in place with masking tape. The occlusive binder is applied to maintain contact and minimize evaporation of the applied test article.
If the test article was solid, it was moistened with physiological saline, (1 mL saline per 1 g of test article) before dermal application. Liquid test articles are administered as received.

Duration of exposure:

24 hours

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 males and 5 females per dose

Control animals:

no

Details on study design:

After an exposure period of 24 hours the occlusive binders were-removed. The exposure sites were then gently wiped with clean gauze to remove as much nonabsorbed test article as possible. Observations for mortality, local reactions, and toxicological findings were recorded for a total of 14 days. Body weights were recorded on the initial day of testing, day 8 and at study termination or day of death.
Only those animals that died during the progress of the study were subjected to a gross necropsy.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 000 mg/kg bw

Based on:

test mat.

95% CL:

>= 0 - <= 40

Mortality:

1 in 10 rabbits (10% mortality)

Any other information on results incl. tables

Table 1 Dosing schedule

Animal Number and Sex	Body Weight (g) at Day				Dosage level g/kg	Dose ml (Total)
	1	8	15	WAD
001m	2.46kg	2.52kg	2.58kg		2.00 g/kg	5.29
002m	2.38kg	2.50kg	2.40kg		2.00 g/kg	5.12
003m	2.74kg	2.49kg	2.57kg		2.00 g/kg	5.89
004m	2.72kg	2.73kg	2.86kg		2.00 g/kg	5.85
005m	2.87kg	2.93kg	3.10kg		2.00 g/kg	6.17
006f	2.86kg	2.34kg	2.60kg		2.00 g/kg	6.15
007f	2.14kg	2.21kg	2.50kg		2.00 g/kg	4.60
008f	2.52kg	2.35kg	2.68kg		2.00 g/kg	5.42
009f	2.60kg	2.61kg	-	2.26kg	2.00 g/kg	5.59
010f	3.05kg	2.95kg	2.98kg		2.00 g/kg	6.56

WAD = weight after death

 

Applicant's summary and conclusion

Interpretation of results:

Category 5 based on GHS criteria

Conclusions:

The dermal LD50 is greater than 2000 mg/kg. Since one death is observed at 2000 mg/kg this warrants classification in category 5 according to GHS criteria (table 3.1.1 note g-ii).

Executive summary:

Results:

Dose level g/kg	No. Rabbits Dosed	No. of Death on Study Day															Cumulative Mortality
		1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
2.0	10	0	0	0	0	0	0	0	0	0	0	0	0	0	1	0	1/10

 

Percent mortality = 10%

95% Confidence Interval = 0-40%

The above data indicate that the dermal LD50 is greater than 2.0 g/kg.