Manganese neodecanoate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-07-23 to 2018-08-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

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:

Manganese neodecanoate

EC Number:

248-374-6

EC Name:

Manganese neodecanoate

Cas Number:

27253-32-3

Molecular formula:

C10H20O2.xMn

IUPAC Name:

Manganese neodecanoate

Test material form:

other: highly viscous, sticky

Details on test material:

- State of aggregation: highly viscous, sticky, red brown

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature in a sealed container

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 27, 28 and 52 weeks old
- Weight at study initiation: 3.8 – 4.4 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
animal #3: 4 hours

Observation period:

animal #1: 72 hours
animal #2: 7 days
animal #3: 72 hours

Number of animals:

3 male rabbits

Details on study design:

TEST SITE
- Area of exposure/Type of wrap if used: approx. 23 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 there is no information about the skin irritation/ corrosion potential of the test item, 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 indicated that the test item is not corrosive to the skin using the procedure described. In order to confirm the response, two additional animals were treated in the same manner.

REMOVAL OF TEST SUBSTANCE
At the end of the exposure period, the residual test item was removed with sterile water from animal no. 1. Due to better solubility, an appropriate solvent, cottonseed oil was subsequently used for rinsing the application site of animal no.1. This was repeated 48 hours post-application as residual test item was still noted. Solely cottonseed oil was used to remove test item residues immediately after patch removal at test sites in animal nos. 2 and 3. 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
- animal #3: 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

Max. score:

4

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:

other: 72, 96 and 120 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: Due to delayed symptom onset, the mean score is calculated from the values 72, 96 and 120 hours after patch removal

Results 4

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 5

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 6

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

ANIMAL #1:
After patch removal during and immediately after sequential application (3 min, 1 hour, 4 hours) no signs of irritation were noted in animal no. 1. It did not show any signs of irritation until the end of the study at 72 hours after patch removal.
ANIMAL #2:
Animal no. 2 showed a delayed onset: no effects were observed at 1 hour, 24 and 48 hours after patch removal. From 72 hours to 6 days after application erythema grade 1 was noted. The mean erythema score of animal no. 2, following grading at 72, 96 and 120 hours after installation of the test material, was calculated to be 1.00.
ANIMAL #3:
Animal no. 3 did not show any sign of irritation until the end of the study at 72 hours after patch removal.

Other effects:

- Neither mortalities nor local or systemic effects were observed.
- There were no significant body weight changes during the observation period, the body weight development was within the expected range.
- Residual test item was noted during sequential application in animal no. 1 and residual test item or discolouration at the application site up to study end in all 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.