2,2,6,6-tetramethylpiperidinooxy

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

29 May to 12 June 1986

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Limit test showing mortality due to severe corrosive effects, thus, the study is considered to be invalid for the estimation of dermal toxicity. Study was not conducted under GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

4 animals (2M / 2F) were used for this study.

GLP compliance:

no

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,2,6,6-tetramethylpiperidinooxy

EC Number:

219-888-8

EC Name:

2,2,6,6-tetramethylpiperidinooxy

Cas Number:

2564-83-2

Molecular formula:

C9H18NO

IUPAC Name:

2,2,6,6-tetramethylpiperidin-1-ol

Test material form:

solid

Remarks:

color: orange

Details on test material:

purchased from Sigma Chemical Company, Munich, Germany.

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Species/Strain: Rabbit (New Zealand albino)
- Source: R and B Enterprise, Hamilton OH
- Body weigth: 3.1 kg (mean)
- Housing: single housing in stainless steel cages
- Diet: Purina Lab Rabbit Chow HF #5325, 150 g daily
- Water: Water supplied from a reverse-osmosis purifier, ad libitum
- Acclimation period: 21 days befor the first test-substance application

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C
- Humidity (%): 40 %
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

24 hours prior to study initiation, fur was clipped from an area of approximately 240 cm2 on the back of each rabbit. 2000 mg/kg b.w. were applied uniformly to the intact application site on the back of each rabbit and were covered with a surgical dressing. The pad was covered by plastic film and then secured by lint-free cloth toweling.
The wrappings were removed after 24 hours, and the application sites were rinsed unsing 0.9% sodium chloride solution then towel dried.

Duration of exposure:

24 hours

Doses:

2000 mg/kg

No. of animals per sex per dose:

2m / 2F

Control animals:

no

Details on study design:

All test rabbits were observed approximately 0.5, 1, 1.5, 2.25, 2.75, 3.5, 4, 4.75, 5, 5.5, 6.5, 21.5 hours after dosing and afterwards once per day for 14 days after removal of the wrappings.
All rabbits were subjected to a gross necropsy.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

< 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

not determinable because of methodological limitations

Mortality:

3 out of 4 animals died during exposure after approximately 4.5, 6 and 21 hours, respectively.

Clinical signs:

other: Clinical observations during exposure included ocular irritation (iridial redness), rapid respiration, decreased motor activity, ataxia, and loss of righting reflex. The surviving rabbit exhibited paleness, irritability, ocular discharge, and severe derma

Gross pathology:

Gross lesions exhibited by the three rabbits which died during exposure included red lungs, red tracheal mucosa, pale liver with tan areas and/or reticulated capsular surface, fluid in the pleural cavity, fluid in the pericardium, and application site skin leasions including orange/brown discoloration and edema. No gross lesion other than those of the application site skin were observed in the surviving rabbit.

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

The acute dermal lethal dose (LD50) of 2,2,6,6-tetramethylpiperidinooxy was found to be lower than 2000 mg/kg bw in male and female rabbits in a limit test. A full test was not performed. Since the test item was shown to be corrosive to the skin and the estimated cause for mortality in this study were severe corrosive effects, the study is considered to be invalid for the estimation of dermal toxicity. Thus, the test substance cannot be classified for this endpoint in accordance to the CLP Regulation (EC) No 1272/2008.