2-ethylhexyl mercaptoacetate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 7 to 21 September 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

Study conducted prior to the adoption of the most recent version of this Guideline

Deviations:

yes

Remarks:

The results of clinical examination were not reported; the age of animals was not indicated; the temperature limits were below the recomended ones.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-ethylhexyl mercaptoacetate

EC Number:

231-626-4

EC Name:

2-ethylhexyl mercaptoacetate

Cas Number:

7659-86-1

Molecular formula:

C10H20O2S

IUPAC Name:

2-ethylhexyl 2-sulfanylacetate

Details on test material:

- Name of test material (as cited in study report): 2-ethylhexyl thioglycolate
- Physical state: colourless liquid
- Expiration date of the lot/batch: January 1994
- Storage condition of test material: at room temperature, away from light

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Elevage cunicole de Val de Selle, France
- Age at study initiation: not reported
- Weight on the day of treatment: mean: 2.9 +/- 0.3 kg
- Housing: individually in polystyrene cages (35 x 55 x 32 cm or 48.2 x 55 x 36.5 cm)
- Diet (e.g. ad libitum): 112 C pelleted diet
- Water (e.g. ad libitum): filtered by a Millipore membrane
- Acclimation period: at least 5 days before the beginning of the study

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 +/- 3
- Humidity (%): 50 +/- 20
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 7 september 1993 To: 21 September 1993

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped using electric clippers

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

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

Duration of treatment / exposure:

4 hour(s)

Observation period:

8 days following exposure

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 6 cm2 gauze patch
- Type of wrap if used: restraining bandage


REMOVAL OF TEST SUBSTANCE
- Time after start of exposure: 4 hours


SCORING SYSTEM: Erythema and oedema were noted from 0 (no observation) to 4 (severe observation)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

other: animals #1 and 3

Time point:

other: 24 + 78 + 72 h

Score:

1.33

Max. score:

4

Reversibility:

fully reversible within: 6 days

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: 24 + 48 + 72 h

Score:

1.66

Max. score:

4

Reversibility:

fully reversible within: 6 days

Results 3

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: 24 + 48 + 72 h

Score:

0.33

Max. score:

1

Reversibility:

fully reversible within: 2 days

Results 4

Irritation parameter:

edema score

Basis:

other: animals #2 and 3

Time point:

other: 24 + 48 + 72 h

Score:

0

Max. score:

4

Other effects:

Results for mortality and behaviour were not reported.

Any other information on results incl. tables

Moderate cutaneous reactions were observed for up to 48 hours after removal of the dressing. They consisted of erythema (scores of 1 and 2) and oedema (score of 1) in 3 animals. Erythema and oedema had reversed by day 6 and 3, respectively.

By day 4, a dryness of the skin was observed at the treatment site. No ulceration or necrosis was observed.

Table 1 Individual skin irritation scores according to the Draize scheme

	Erythema			Oedema
Animal No	1	2	3	1	2	3
After 0.5 - 1 h	1	2	1	0	0	0
After 24 h	2	2	2	1	0	0
After 48 h	1	2	1	0	0	0
After 72 h	1	1	1	0	0	0
Mean score 24-72 h	1.44			0.11
Day 5	1	1	1	0	0	0
Day 6	0	0	0	0	0	0
Day 7	0	0	0	0	0	0
Day 8	-	0	0	-	0	0

- cutaneous examination not performed

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The substance was found to be slightly irritating to rabbits skin with some erythema observed and scored 2. No more erythema were observed at day 6 post-treatment. Only slight oedema (score 1) was observed in one animal at 24 h following application.

Executive summary:

A single dose of 0.5 mL undiluted EHTG was applied to the skin of 3 male New Zealand White rabbits under a semi-occlusive dressing for four hours following OECD test guideline 404. Skin reactions were observed approximately 1 hour, 24, 48 and 72 hours after removal of the dressing and then daily until 8 days in order to observed their reversibility. The mean values of the scores for erythema and oedema were calculated for each animal. The mean scores over 24, 48 and 72 hours for individual animals were 1.3, 1.7, and 1.3 for erythema and 0.0, 0.0, and 0.3 for edema. No ulceration of necrosis was noted. Erythema and edema had reversed by day 6 and by day 3, respectively. EHTG was slightly irritating under the conditions of this test.