Registration Dossier

Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP study with adequate details. No COA however the test article was described as tert-amyl peroxypivalate.

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)
GLP compliance:
no
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
additive
Test material form:
aerosol dispenser: not specified
Remarks:
aerosol
Details on test material:
A sample of Tert-Amyl peroxypivalate was received from the principal
on 3rd June 1981. Tert- Amy1peroxypivalate is a clear, colorless liquid.

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals or test system and environmental conditions:
Five male a.nd five female SPF-reared rats (Cpb: WU, Wistar Random) were obtained from the Central Institute for the Breeding of Laboratory Animals TNO, Zeist, The Netherlands. At the beginning of the study the mean body weight of the males was 16.8 g and that of the females 142 g. During the observation period the animals were kept in stainless steel cages. (5 to a cage), which were suspended in an open rack in an animal room. They received ad libitum the Institute's stock diet for rats and bottled unfluoridated water. During the exposure. the animals were deprived o.f water and food. The temperature and the relative humidity in the animal room were set and controlled at 21 +/- 1 °C and 50 - 60 per cent, respectively.

Administration / exposure

Route of administration:
inhalation: aerosol
Type of inhalation exposure:
whole body
Vehicle:
air
Details on inhalation exposure:
The animals w.ere exposed in a stainless steel exposure chamber having a capacity of 1.5 m3 under dynamic airflow conditions. Through a glass door at the front of the exposure chamber the animals could be observed continuously durtng the exposure period. The front door is provided with several openings for taking samples of the test atmosphere at different locations.

During the exposure the animals were housed in wire mesh stainless steel
cages, which were suspended in a rack in the exposure chamber. Individual
housing was used to prevent crowding and to minimise filtration of
inspired air by the animals' fur.

Tert- Amylperoxypivalate was dispersed to a fine mist by means of a
stainless steel glass aerodynamic nozzle nebuliser, operated at a
pressure of 5 atm giving an airflow rate of 2.2 m3/h. The nebuliser was
provided with a baffle in order to prevent the larger droplets from
entering into the test atmosphere of the inhalation chamber. The mist was
passed through the exposure chamber with a total airflow of 2.4m3/h.

The concentration of Tert- Amyl peroxypivalate in a sample of the test
atmosphere was determined according to a method provided by the sponsor.
A sample of the test atmosphere was obtained by passing a measured quantity
of this air through an impinger filled with xylene.
Analytical verification of test atmosphere concentrations:
yes
Duration of exposure:
ca. 4 h
Concentrations:
9.5 g/m3 air
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
The animals were exposed to the test material for 4 hours. After the exosure period the animals were returned to their living cages for an observation period of 2 weeks. During this period the body weight of the animals was recorded at days 1, 2, 4, 7 and 14. At the end of the observation period the animals were killed by exsanguination from the abdominal aorta under ether anaesthesia, autopsied and examined for gross pathological changes.

Results and discussion

Effect levels
Key result
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 9 500 mg/m³ air
Based on:
test mat.
Exp. duration:
4 h
Mortality:
No mortality occurred during the exposure period and the subsequent observation period of 14 days.
Clinical signs:
other: During the last two hours of the exposure period the animals showed laboured respiration, but they recovered completely whithin a couple of hours after termination other exposure.
Body weight:
Both males and females lost body weight during the first day of the observation period, and thereafter they grew in a normal way.
Gross pathology:
Gross examination at autopsy did not reveal any abnormalities that were considered to be treatment-related.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The results of the present acute inhalation toxicity study in rats allow the conclusion that exposure to Tert- Amyl peroxypivalate at a concentration of 9.5 g/m3 air during four hours did not result in mortality or in any other major sign of intoxication.
Executive summary:

1. The acute inhalation toxicity of Tert- Amyl peroxypivalate was studied by exposing male and female rats one single time for 4 hours. to an atmosphere containing an aerosol of Tert-Amyl peroxypivalate.

2. Exposure of rats to the maximum attainable concentration of 9.5 g/m3 air did not result in mortality or any other major sign of intoxication.