Fatty acids, C16 and C18-22-unsatd., C16-18 and C18-unsatd. alkyl esters

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

15 - 18 Jan 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

- Principle of test: 6 New Zealand albino rabbits were exposed dermally under occlusive conditions to the undiluted test substance for 24 h. The test substance was applied to abraded and non-abraded skin sites. The skin was observed for erythema and edema (Draize scoring system) 1 and 48 h after removal of the test substance.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Fatty acids, C16 and C18-22-unsatd., C16-18 and C18-unsatd. alkyl esters

EC Number:

292-792-1

EC Name:

Fatty acids, C16 and C18-22-unsatd., C16-18 and C18-unsatd. alkyl esters

Cas Number:

90990-29-7

Molecular formula:

not applicable, substance is UVCB

IUPAC Name:

Fatty acids, C16 and C18-22 - unsatd., C16-18 and C18 unsatd. alkyl ester

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Nottingham University, School of Agriculture, Nottingham, UK
- Weight at study initiation: 2.59 - 3.35 kg (range: males and females)
- Housing: individually in suspended metal cages
- Diet: rabbit diet (John Waring (Feeds) Limited, Shardlow, Derbyshire, UK), ad libitum
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3
- Air changes (per hr): at least 20
- Photoperiod (hrs dark / hrs light): 12 / 12

Test system

Type of coverage:

occlusive

Preparation of test site:

other: clipped and abraded

Remarks:

test site on right flank of the animals

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 mL

Duration of treatment / exposure:

24 h

Observation period:

48 h

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: The test substance was introduced under a composite patch which consisted of a 2.5 cm square of absorbent lint B.P.C. backed by a 2.5 cm square of polythene with a final backing of a 4 cm square of lint. The patch was held in position by two lengths of sleek adhesive strapping in the form of a cross.

REMOVAL OF TEST SUBSTANCE
- Washing: Any residual test material was removed by gentle swabbing the test site with cotton wool soaked in lukewarm water.
- Time after start of exposure: 24 h

OBSERVATION TIME POINTS
1 and 48 h after removal of the patches


SCORING SYSTEM: Draize scoring system

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: #3

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 48 h

Results 2

Irritation parameter:

erythema score

Basis:

animal: #1, #2, #4, #5 and #6

Time point:

other: 1 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 3

Irritation parameter:

erythema score

Basis:

mean

Remarks:

of 6 animals

Time point:

48 h

Score:

0

Max. score:

4

Reversibility:

other: not apllicable

Results 4

Irritation parameter:

edema score

Basis:

mean

Remarks:

of 6 animals

Time point:

other: 1 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 5

Irritation parameter:

edema score

Basis:

mean

Remarks:

of 6 animals

Time point:

48 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritant / corrosive response data:

Intact skin:
At the 1-h reading time point, very slight erythema (score 1) was observed in 1/6 animals. The erythema had cleared completely within 48 hours after patch removal. No oedema was observed in any animal at any time reading time point.

Abraded skin:
Very slight erythema (score 1) was observed in 2/6 animals 1 h after patch removal. All evidence of irritation had disappeared 48 h after patch removal.

Any other information on results incl. tables

Table 1. Results of irritation test on intact and abraded skin sites 1h and 48 h after patch removal

Observation time	Rabbit no.
	1		2		3		4		5		6
	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema
Intact skin
1 h	0	0	0	0	1	0	0	0	0	0	0	0
48 h	0	0	0	0	0	0	0	0	0	0	0	0
Abraded skin
1 h	0	0	1	0	1	0	0	0	0	0	0	0
48 h	0	0	0	0	0	0	0	0	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

other: Study can not be used for classification

Conclusions:

The result of the in vivo skin irritation study is not conclusive with respect to non-classification or classification as a skin irritant and therefore requires further evaluation and/or data generation.