2-ethylhexanoic acid, iron salt

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-08-14 to 2018-08-27

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

2015-07-28

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2018-04-26

Test material

Test material information

Constituent 1

Reference substance name:

2-ethylhexanoic acid, iron salt

EC Number:

243-169-8

EC Name:

2-ethylhexanoic acid, iron salt

Cas Number:

19583-54-1

Molecular formula:

C8H16O2.xFe

IUPAC Name:

2-ethylhexanoic acid, iron salt

Test material form:

other: highly viscous, sticky

Details on test material:

- State of aggregation: highly viscous, sticky, black

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: in a closed container, do not expose to air - keep on cool place

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, 97633 Sulzfeld, Germany
- Age at study initiation: approx 57 and 53 weeks old
- Weight at study initiation: 3.8 – 4.0 kg
- Housing: individually housed in ABS-plastic or Noryl rabbit cages, floor 4200 cm2
- Diet (ad libitum): autoclaved hay and Altromin 2123 maintenance diet for rabbits, rich in crude fibre
- Water (ad libitum): tap water
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 18 ± 3 °C
- Relative humidity: 55 ± 10 %
- Air changes: at least 10 x / 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 g of the test item
In order to ensure good skin contact, it was moistened with aqua ad injectionem.

Duration of treatment / exposure:

animal #1: 3 minutes, 1 hour and 4 hours
animal #2: 4 hours

Observation period:

animal #1: 72 hours
animal #2: 6 days

Number of animals:

2 male rabbits

Details on study design:

TEST SITE
- Area of exposure/Type of wrap if used: approx. 24 hours before the test, the fur was removed from the dorsal area of the trunk by using an electric clipper. The test item was applied to a small area (approx. 6 cm²) of skin on one side of the dorsal area and covered with a gauze patch, which was held in place with a non-irritating tape. The untreated other side served as control. The test item was applied to the patch first, moistened with the smallest amount of aqua ad injectionem and then applied to the skin. The patch was fixed with a semi-occlusive dressing. The limits of the application site were marked with an ink marker.

INITIAL AND CONFIRMATORY TESTING
As the test item was expected to produce severe irritancy/corrosion, a single animal test was employed. Up to three test patches were applied sequentially to the animal. The first patch was removed after three minutes. No serious skin reaction was observed, so a second patch was applied at a different site and removed after one hour. The observations at this stage indicated that exposure can humanely be allowed to extend to four hours, so a third patch was applied and removed after four hours, and the response was graded. No corrosive effect was observed after the last patch was removed, so the animal was further observed.

The results of the initial test did not indicate the test item to be corrosive or a severe irritant to the skin using the procedure described. In order to confirm the response, one additional animals were treated in the same manner.

REMOVAL OF TEST SUBSTANCE
As the test item showed a water-repellent effect, an appropriate solvent, cottonseed oil was used for rinsing the application site after patch removal. The solvent was chosen in order not to alter the existing response or the integrity of the epidermis.

OBSERVATION TIME POINTS
- animal #1: immediatley and 1 hour, 48, 72 and 96 hours after patch removal
- animal #2: 1 hour, 24, 48 and 72 hours after patch removal

SCORING SYSTEM
according to the Draize scale

FURTHER OBSERVATIONS
- body weights: prior to the administration and at the end of the observation period
- local effects such as hyperplasia, scaling, discolouration, fissures and scabs
- systemic effects

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 3

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 6 days

Results 4

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

ANIMAL #1:
After patch removal during sequential application (3 min, 1 hour) no signs of irritation were noted in animal no. 1. Erythema grade 1 was first observed 24 hours after 4-hour exposure. The effect was reversible within 72 hours after application of the test material. The mean erythema score of animal no. 1, following grading at 24, 48 and 72 hours after installation of the test material, was calculated to be 0.67.

ANIMAL #2:
Animal no. 2 showed erythema grade 1 from 1 hour until 5 days after patch removal. The effect disappeared within 6 days after application. The mean erythema score of animal no. 2, following grading at 24, 48 and 72 hours post-application, was calculated to be 1.00.

Other effects:

- Neither mortalities nor significant clinical signs of toxicity were observed.
- There were no significant body weight changes during the observation period, the body weight development was within the expected range.
- A slight discolouration at the application site due to residual test item was noted at every time of observation in both animals.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

According to Regulation (EC) No 1272/2008 and subsequent adaptations, the test item is not irritating to the skin and does not require classification and labelling.