2-(dimethylamino)-2-methylpropan-1-ol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03 - 24 Feb 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

dressing was occlusive, 24 h exposure, no experimental 48 h reading performed, no data for the observation period given

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-(dimethylamino)-2-methylpropan-1-ol

EC Number:

230-279-6

EC Name:

2-(dimethylamino)-2-methylpropan-1-ol

Cas Number:

7005-47-2

Molecular formula:

C6H15NO

IUPAC Name:

2-(dimethylamino)-2-methylpropan-1-ol

Details on test material:

- Name of test material (as cited in study report): 2-Dimethylamino-2-methyl-1-propanol, 73% DMAMP, Polymeen A (P-2614)
- Substance type: clear, pale yellow liquid
- Analytical purity: 72.03%
- Lot/batch No.: 730H18DF36
- pH: 12.5

Specific details on test material used for the study:

- Lot No, 73 0H18DF3 6
- 2-Dimethylamino-2-methyl-1-propanol 72.03%
- APHA (color) 15
- pH 12.5
- Sp. Gr. 0.947
- Made from DMAMP 80 Lot No. OH18DF36

Test animals

Species:

rabbit

Strain:

other: albino

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2.6 ± 0.3 kg

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

other: not required, untreated sites of the same animal served as control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL

Duration of treatment / exposure:

24 h

Observation period:

21 days
Reading time points: 24 and 72h

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: The skin from the back of each rabbit was clipped free of hair. Two intact skin sites and two abraded sites were used for exposure.
- Type of wrap if used: the exposed skin area was covered with gauze and the trunk wrapped in a rubberised impervious cloth and a flexible wire screen held in place with tape, respectively

REMOVAL OF TEST SUBSTANCE
- Washing (if done): the treated skin areas were cleaned
- Time after start of exposure: 24 h

SCORING SYSTEM: Draize scoring system

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24 h

Score:

4

Max. score:

4

Reversibility:

other: reversibility not applicable

Remarks on result:

other: the animal was sacrificed after Day 1 due to a broken leg

Results 2

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

out of animal 2, 3, 4, 5 and 6

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: no 48 h data are available; for calculation of mean scores, the 48 h values were assumed to be the same as those at 24 h (worst case assumption: persistence of effects seen at 24 h over 48 h)

Results 3

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24 h

Score:

2

Max. score:

4

Reversibility:

other: reversibility not applicable

Remarks on result:

other: the animal was sacrificed on Day 1 due to a broken leg

Results 4

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: no 48 h data are available; for calculation of mean scores, the 48 h values were assumed to be the same as those at 24 h (worst case assumption: persistence of effects seen at 24 h over 48 h)

Results 5

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.5

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: no 48 h data are available; for calculation of mean scores, the 48 h values were assumed to be the same as those at 24 h (worst case assumption: persistence of effects seen at 24 h over 48 h)

Results 6

Irritation parameter:

edema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: no 48 h data are available; for calculation of mean scores, the 48 h values were assumed to be the same as those at 24 h (worst case assumption: persistence of effects seen at 24 h over 48 h)

Results 7

Irritation parameter:

edema score

Basis:

animal #5

Time point:

24/48/72 h

Score:

1.5

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: no 48 h data are available; for calculation of mean scores, the 48 h values were assumed to be the same as those at 24 h (worst case assumption: persistence of effects seen at 24 h over 48 h)

Results 8

Irritation parameter:

edema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

1.5

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: no 48 h data are available; for calculation of mean scores, the 48 h values were assumed to be the same as those at 24 h (worst case assumption: persistence of effects seen at 24 h over 48 h)

Irritant / corrosive response data:

At the 24-hour time point, severe erythema and moderate to severe edema was noted at the intact skin sites of all rabbits (see Table 1). One rabbit broke its leg on day 1 and was sacrificed. For the remaining 5 animals, the erythema was equally severe at the 72-hour time point, while the edema was completely reversed. The treated intact skin sites were still affected by erythema and edema on day 21, although the effects were less severe with signs of healing. The effects on abraded skin were the same as on the intact skin.

Other effects:

There were no effects on the body weight of the animals.

Any other information on results incl. tables

Table 1: individual erythema and edema scores for intact skin

Observation time	Rabbit No.
	1		2		3		4		5		6
	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema
24 h	4	2	4	4	4	3	4	2	4	3	4	3
48 h	No experimental data available; for calculation of mean scores, the 48 h values were assumed to be the same as those at 24 h (worst case assumption)
72 h	*	*	4	0	4	0	4	0	4	0	4	0

* rabbit sacrificed on day 1 due to a broken leg

Table 2: calculation of mean scores for intact skin

	Rabbit No.
	1		2		3		4		5		6
	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema
Mean value 24+48+72 h	*	*	4	2.67	4	2	4	1.33	4	2	4	2

* rabbit sacrificed on day 1 due to a broken leg

Applicant's summary and conclusion

Interpretation of results:

irritating

Conclusions:

CLP: Cat. 2, H315
DSD: Xi, R38

Executive summary:

The primary skin irritation study was conducted on DMAMP as supplied. The test was conducted on a group of six albino rabbits weighing from 2.650.3 kg. The skin from the back area of each rabbit was clipped free of hair. The skin on the left side of the middorsal line was left intact while the skin on the right side was abraded at two sites by making minor epidermal incisions in a tic-tac-toe pattern with a blunt hypodermic needle. The abrasions were minor incisions through the stratum corneum, but not deep enough to disturb the dema or produce bleeding. A 0.5 ml of P-2614 as supplied was applied to each site , two intact and two abraded, and covered with a gauze pad. The entire trunk was then wrapped with a rubberized impervious cloth and a flexible wire screen held in place by tape. After 24 h exposure, the bindings and patches were removed and the treated sites were gently cleaned. The skin reactions were scored immediately (24 h) and a t the end of 72 h (48 h after first scoring).

At 24 h the test material produced erythema and edema on the intact skin but produced moderate to severe erythema and edema on the abraded skin sites . One of the rabbits broke its leg a fter one day on treatment, so the animal was sacrificed. The average irritation score for the five rabbits was 5.5 + 0.4. Since the material produced severe skin irritation , the animals were held for observation up to 21 days. The treated skin sites were not normal by day 21, but the skin sites showed erythema and slight healing. The average body weight gains of the treated animals were normal.