Amines, C16-18-alkyldimethyl

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to OECD guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Amines, C16-18-alkyldimethyl

EC Number:

269-915-2

EC Name:

Amines, C16-18-alkyldimethyl

Cas Number:

68390-97-6

Molecular formula:

R-N(Me)2, whereas R= C16-18-alkyl (even numbered, unbranched, saturated)

IUPAC Name:

N,N-dimethyl-C16-18-(even numbered)-alkyl-1-amines

Details on test material:

Based on the qualitative and quantitative information on the composition, the sample used is representative of the boundary composition shared and agreed by each registrant.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd., Moston, Sandbach, Cheshire, U.K.
- Age at study initiation: 12-16 weeks
- Weight at study initiation: 2.00- 3.00 kg
- Housing: individually in suspended metal cages
- Diet: Rabbit diet, Preston Farmers Limited, New Leake, Boston, Lincolnshire, U.K., ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 13-21
- Humidity (%): 47-69
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 mL

VEHICLE
- Amount(s) applied (volume or weight with unit):
- Concentration (if solution):
- Lot/batch no. (if required):
- Purity:

Duration of treatment / exposure:

4 h

Observation period:

14 days with observation time points at 1 h, 24h, 48 h and 72 h and 7 days

Number of animals:

groups of 6 animals

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: strip of surgical adhesive tape, elasticated corset

REMOVAL OF TEST SUBSTANCE
- Washing: gentle swabbing with cotton wool soaked in distilled water
- Time after start of exposure: 4 h

SCORING SYSTEM:
Erythema and eschar formation:
No erythema:0
Very slight erythema (barely perceptible):1
Well-defined erythema: 2
Moderate to severe erythema: 3
Severe erythema (beet redness) to slight eschar formation (injuries in depth): 4

Oedema formation:
No oedema: 0
Very slight oedema (barely perceptible):1
Slight oedema (edges of area well-defined by definite raising):2
Moderate oedema (raised approximately 1 millimetre ):3
Severe oedema (raised more than 1 millimetre extending beyong the area of exposure):4

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: #1 #3 and #6

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Results 2

Irritation parameter:

erythema score

Basis:

animal: #2,#4 and #5

Time point:

other: 1 h

Score:

2

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Results 3

Irritation parameter:

erythema score

Basis:

animal: #1, #2, #3, #5 and #6

Time point:

24 h

Score:

2

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Results 4

Irritation parameter:

erythema score

Basis:

animal: #1, #2, #3, #5 and #6

Time point:

other: 48 and 72 h

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Remarks on result:

other: No score could be determined due to other skin effects. Effects after 14 days: blanching of the skin, brown discoloration of the epidermis, scabbing, loss of skin flexibility, thickening of skin, glossy skin, dry straw-coloured crust, dried blood.

Results 5

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Remarks on result:

other: effects after 14 days: Skin glossy, desquamation, loss of skin suppleness, thickening of dermal tissue, dry straw coloured crust, scar tissue

Results 6

Irritation parameter:

edema score

Basis:

animal: #1,#2, #3 and #4

Time point:

other: 1 h

Score:

2

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Results 7

Irritation parameter:

edema score

Basis:

animal: #5 and #6

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Results 8

Irritation parameter:

edema score

Basis:

animal: #1, #2, #4 and #6

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Results 9

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2.67

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Results 10

Irritation parameter:

edema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

other: unclear due to other skin effects

Irritant / corrosive response data:

Severe dermal responses were produced after 4 h of exposure. The adverse skin reactions sometimes precluded accurate evaluation of erythema and oedema.
Very slight to well-defined erythema and slight to moderate oedema were noted one hour after patch removal. The reactions increased in severity and at subsequent observations were identified as well-defined erythema, slight to severe oedema, blanching of the skin, a brown discoloration of the epidermis, haemorrhage of the dermal capillaries, scabbing, loss of skin flexibility and elasticity, thickening of the skin, glossy skin, a dry straw-coloured crust (possible hyperkeratinisation), dried blood, desquamation. Scar tissue, indicative of dermal corrosion was noted in two rabbits.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (corrosive) based on GHS criteria

Conclusions:

The substance causes visible necrosis of the skin tissue at the site of contact when tested on the intact skin of an animal for a period of not more than four hours. Therefore the test item is classified as corrosive.

Executive summary:

The irritancy/corrosivity was determined by semi-occlusive exposure of the intact skin of a group of six New Zealand white rabbits, for a period of four hours. The study was based on the OECD 404.

 After 4 h exposure to the substance, washing with distilled water and an observation period of 14 days clear corrosiveness was determined. In 6/6 animals no erythema score and in 6/6 no edema score could be determined after 7 and 14 days due to other severe effects on the skin (i.e. scar tissue, thickening of the dermal tissue, desquamation.). Therefore the substance was classified as cossosive.