Propanoic acid, 2-hydroxy-, C12-13-branched alkyl esters

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

01 - 08 Jun 1992

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions. The exposure was occlusive.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

occlusive exposure

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Propanoic acid, 2-hydroxy-, C12-13-branched-alkyl esters

IUPAC Name:

Propanoic acid, 2-hydroxy-, C12-13-branched-alkyl esters

Details on test material:

- Name of test material (as cited in study report): (C12-C13) Alkyl lactate
- Analytical purity: 100% (UVCB)

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Padre Antonio, Mariano Comense, Italy
- Weight at study initiation: 2.5 - 3.5 kg
- Housing: the rabbits were caged individually in stainless steel cages (45.0 cm x 50.0 cm x 38.0 cm).
- Diet: standard pellet complete diet (Rieper), ad libitum
- Water: filtered tap water, ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 01 Jun 1992 To: 08 Jun 1992

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

other: sesame seed oil

Controls:

other: the untreated sites of the same animal served as the control

Amount / concentration applied:

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

VEHICLE
- Amount(s) applied (volume or weight with unit): 0.5 g of the solid test substance was mixed with 0.5 mL vehicle to a paste

Duration of treatment / exposure:

4 h

Observation period:

7 days
Reading time points: 1, 24, 48 and 72 h

Number of animals:

6 males

Details on study design:

TEST SITE
- Area of exposure: approximately 24 hours before the test an area on the dorsal side and flank of approximately 24.0 cm² was clipped and shaved. An area of approximately 20 cm² on the right flank was used for the application of the test substance.
- Type of wrap if used: the test site was covered with a square gauze pad (2.5 x 2.5 cm) fixed to adhesive tape (Hansamed strips). The pad was fixed to the skin with strips of hypoallergenic tape (Blenderm 3M) and the trunk wrapped with rubberised cloth (Acrylastic Beyersdorf AG Hamburg).

REMOVAL OF TEST SUBSTANCE
- Washing (if done): the remains of the test substance were removed by washing the skin site with a pad soaked in distilled water.
- Time after start of exposure: 4 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:

other: mean after 24, 48 and 72 h

Score:

0.17

Max. score:

4

Reversibility:

fully reversible within: 48-72 h

Remarks on result:

other: 2/6 animals: very slight erythema at the 1 h reading time point

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

of all 6 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: reversibility not applicable

Irritant / corrosive response data:

2/6 rabbits had very slight erythema from the 1 h reading time point, which persisted until the 24 h reading time point in 1/6, and until the 48 h reading time point in 1/6 rabbits, respectively. All observed skin irritation effects were completely reversible within 72 hours. No edema was observed at any reading time point.

Other effects:

No other local or systemic effects were reported.

Any other information on results incl. tables

Table 1. Individual skin irritation scores

Observation time	Rabbit no.
	1		2		3		4		5		6
	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema	Erythema	Edema
1 h	1	0	0	0	0	0	1	0	0	0	0	0
24 h	1	0	0	0	0	0	1	0	0	0	0	0
48 h	1	0	0	0	0	0	0	0	0	0	0	0
72 h	0	0	0	0	0	0	0	0	0	0	0	0
Mean value 24 + 48 + 72 h	0.67	0.00	0.00	0.00	0.00	0.00	0.33	0.00	0.00	0.00	0.00	0.00

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified