Fatty acids, C12-18

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

01 Feb - 08- Feb 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP - Guideline study, tested with the source substance CAS 143-07-7. In accordance to the ECHA guidance document "Practical guide 6: How to report read-across and categories (March 2010)", the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Lauric acid

EC Number:

205-582-1

EC Name:

Lauric acid

Cas Number:

143-07-7

Molecular formula:

C12H24O2

IUPAC Name:

lauric acid

Details on test material:

- Name of test material (as cited in study report): PRIFRAC 2922
- Physical state: solid
- Analytical purity: not given
- Storage condition of test material: at room temperature in the dark

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Broekman Institute, Someren / The Netherlands (SPF-Quality)
- Age at study initiation: 13 weeks
- Weight at study initiation: 2427 - 2547 g
- Housing: individually in cages with perforated floors equipped with an automatic drinking system (ITL, Bergen / The Netherlands).
- Diet: standard laboratory rabbit diet (LKK-20, pellet diameter 4 mm, Hope Farms, Woerden / The Netherlands); approx. 100 g / day.
- Water (ad libitum): free access to tap-water diluted with decalcified water
- Acclimation period: at least five days under test conditions


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3
- Humidity (%): 30 - 70
- Air changes (per hr): air-conditioned with 7.5 - 15
- Photoperiod (hrs dark / hrs light): 12 / 12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

other: untreated skin sites of same animals

Amount / concentration applied:

0.5 g

Duration of treatment / exposure:

4 hours

Observation period:

8 days

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 10 cm x 10 cm
- Type of wrap if used: the dressing was wrapped around the abdomen and secured with an elastic bandage.


REMOVAL OF TEST SUBSTANCE
- Washing: Four hours after the application, the dressing was removed and the remaining test substance was removed using a dry tissue and subsequently a tissue moistened with tap water.


CORING SYSTEM:
Erythema:
0 - no erythema
1 - very slight erythema (barely perceptible)
2 - well-defined erythema
3 - moderate to severe erythema
4 - severe erythema (beet redness) to slight eschar formation (injuries in deep)

Edema:
0 - no edema
1- very slight edema (barely perceptible)
2 - slight edema (edges of area well defined by definite raising)
3 - moderate edema (raised appr. 1 mm)
4 - severe edema (raised >1 mm and extending beyond area of exposure)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24 - 48 - 72 h

Score:

0.4

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24 - 48 - 72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects

Irritant / corrosive response data:

The observed skin irritation consisted of very slight erythema. The irritation was reversible in one animal within 24 hours, in the second animal within 48 hours and in the third animal within 7 days after exposure.
No corrosive effect was evident on the skin.

Other effects:

No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Any other information on results incl. tables

Readings:

Time	Animal	Erythema	Edema	Other findings
1 h	1	1	0
	2	1	0
	3	1	0
24 h	1	1	0	+/- 50% of exposed area
	2	0	0
	3	1	0	+/- 50% of exposed area
48 h	1	1	0	+/- 50% of exposed area
	2	0	0
	3	0	0
72 h	1	1	0	+/- 5% of exposed area
	2	0	0
	3	0	0
7 d	1	0	0
	2	0	0
	3	0	0
mean 24 - 48 - 72 h	1	1.0	0.0
	2	0.0	0.0
	3	0.3	0.0
mean		0.4	0.0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU