Hexanoic acid, 2-ethyl-, zinc salt, basic

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996-11-20 to 1996-12-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1992-07-17

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Hexanoic acid, 2-ethyl-, zinc salt, basic

EC Number:

286-272-3

EC Name:

Hexanoic acid, 2-ethyl-, zinc salt, basic

Cas Number:

85203-81-2

Molecular formula:

C16H30O4Zn

IUPAC Name:

zinc(2+) bis(2-ethylhexanoate)

Test material form:

liquid: viscous

Details on test material:

- Name of test material (as cited in study report): Acima zinc octoate
- Physical state: viscous colourless liquid
- Stability under storage conditions: stable
- 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
- Age at study initiation: approx. 7 weeks
- Weight at study initiation: 1290 - 1555 g
- Housing: individually in labelled cages with perforated floors (Scanbur Denmark and 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; hay (BMI, Helmond, the Netherlands) was provided once a week
- Water (ad libitum): tap-water diluted with decalcified water
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 21°C
- Relative humidity: 50%
- Air changes: approx. 15 air changes/hour
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL of the undiluted test substance was applied to the skin

Duration of treatment / exposure:

4 hours

Observation period:

approximately 1, 24, 48 and 72 hours and 7, 14 and 21 days after the removal of the dressings and test substance

Number of animals:

3 male rabbits

Details on study design:

A health inspection was performed prior to the commencement of treatment, to ensure that the animals were in a good state of health. Special attention was paid to the skin to be treated, which was intact and free from abnormalities.
TEST SITE
- Area of exposure: approximately 24 hours before treatment, the dorsal fur was clipped with electric clippers, exposing an area of approximately 150 square centimeters (10 x 15 cm^2).
On test day 1 the test substance was applied to the skin of one flank, using a surgical gauze patch of 2 X 3 cm. The patch was mounted on Micropore tape (Supplier, 3M, St. Paul, U.S.A.) which was wrapped around the abdomen and secured with Coban elastic bandage (Supplier, 3M, St. Paul, U.S.A.).


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

Whenever considered necessary the treated skin areas were re-clipped at least 3 hours before the observations, to facilitate the scoring.

SCORING SYSTEM: according to the Draize scale
The irritation scores and a description of all other (local) effects were recorded. Adjacent areas of the untreated skin of each animal served as controls.

OBSERVATIONS
- Mortality/Viability: twice daily
- Toxicity: at least once daily
- Body weight: day of treatment (prior to application)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 21 days

Remarks on result:

other: Thick layer of scales was observed on day 7; Bald skin was observed on day 14

Results 2

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: day 21

Results 3

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

fully reversible within: day 21

Remarks on result:

other: Yellow discolouration of the skin in 40% of the treated area was observed 72 hours after test item administration and on day 7; Thick layer of scales was observed on day 7 and bald skin on day 14.

Results 4

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: day 21

Results 5

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: day 14

Remarks on result:

other: Yellow discolouration of the skin and a thick layer of scales were observed on day 7 and bald skin on day 14.

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: day 21

Irritant / corrosive response data:

Four hours exposure to the test substance resulted in well-defined or moderate to severe erythema and slight or moderate oedema in the treated skin areas of the three rabbits. Yellow discolouration of the skin was noted in two animals 72 hours and/or 7 days after exposure. A thick layer of scale was observed after 7 days and bald skin after 14 days in all animals.
The skin irritation had resolved within 21 days after exposure in all animals.
There was no evidence of a corrosive effect on the skin.
Greasy remnants of the test substance were present on the skin of all animals on day 1. Also, very slight erythema (grade 1) was observed in two animals 1 hour after exposure. Well-defined erythema was observed in the third animal 1 hour after exposure.

Other effects:

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

Applicant's summary and conclusion

Interpretation of results:

irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

According to the EC-Commission directive 67/548/EEC and its subsequent amendments, the test substance is irritating to the skin.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the substance is not classified.