N-2-hydroxyethyllactamide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was conducted similar to a appropriate OECD test guideline and in compliance with GLP. Only limited information on the test material is available. No analytical purity of the test substance is given.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

adopted 28 July 2015

Deviations:

yes

Remarks:

The test material was applied to the intact/abraded skin for 24 hours under occlusive coverage and the evaluation of skin irritating effects were only performed 24 and 72 h. Relative humidity/temperature exceeded guideline specific standard values

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

N-2-hydroxyethyllactamide

EC Number:

226-546-1

EC Name:

N-2-hydroxyethyllactamide

Cas Number:

5422-34-4

Molecular formula:

C5H11NO3

IUPAC Name:

N-2-hydroxyethyllactamide

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2300 – 2800 g
- Housing: animals were housed in grid bottomed metal cages
- Diet: pelleted rabbit diet (Dalgety Spillers Limited), ad libitum
- Water: mains drinking water, ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 15 – 24
- Humidity (%): 80 – 90
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

occlusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

other: untreated sites of the same animal served as control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 0.5 mL

Duration of treatment / exposure:

24 h

Observation period:

72 hours
Reading time points: 24 and 72 h (post start of exposure)

Number of animals:

6 females

Details on study design:

TEST SITE
- Area of exposure: Immediately before dosing the left flank of the animals' back was lightly abraded in a criss-cross pattern using the point of a 25 x 0.6 mm sterile disposable hypodermic needle. The abrasions were sufficiently deep to damage the stratum corneum but not to penetrate the dermis. The skin of the right flank remained intact.
- Type of wrap if used: The undiluted test material was placed over two 2.5 cm square surgical lint pads attached to a length of 5 cm wide sleek plastic adhesive wrapping. The lint squares were then placed in contact with the animals skin, one lint suare with abraded skin and one lint square in contact with intact skin, and secured in position by the attached sleek adhesive tape. The trunk of the animal was then encircled with a length of Elastoplast elastic adhesive bandage 7.5 cm wide.

REMOVAL OF TEST SUBSTANCE
- Washing: Excess test material remaining on the skin was removed by gentle wiping with cotton wool soaked in warm water.
- 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:

mean

Remarks:

of 6 animals

Time point:

24/48/72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

of 6 animals

Time point:

24/48/72 h

Score:

0.11

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritant / corrosive response data:

Well defined erythema (grade 2) were observed at two abraded and two intact skin sites and very slight erythema (grade 1) was apparent at two abraded and two intact treatment sites following the twenty four hour treatment period. Very slight edematous (grade 1) reaction was apparent at one abraded skin site and at one intact skin site. The irritation described declined rapidly, very slight irritation of the treated skin remained in one animal only on termination of the study. The calculated mean values for erythema and edema were 0.67 and 0.11, respectively.

Any other information on results incl. tables

Table 1: Results of skin irritation studies (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	0	0	1	0	0	0	1	0	2	1	2	0
48 h^a)	0	0	1	0	0	0	1	0	2	1	2	0
72 h	0	0	0	0	0	0	0	0	0	0	0	0
Mean value 24 + 48 + 72 h	0	0	0.67	0	0	0	0.67	0	1.33	0.67	1.33	0

a) 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)

Table 2: Results of skin irritation studies (abraded 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	0	0	1	0	0	0	1	0	2	1	2	0
48 h^a)	0	0	1	0	0	0	1	0	2	1	2	0
72 h	0	0	1	0	0	0	0	0	0	0	0	0
Mean value 24 + 48 + 72 h	0	0	1	0	0	0	0.67	0	1.33	0.67	1.33	0

a) 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)

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

CLP: not classified