Skin Corrosion Test on Rabbit Skin

KIWITA
Jan 15
4 min read

Updated: Jan 18

To: APA Corporation Co., Ltd.

April 26, 2013

Analysis and Test Report

We hereby report, as attached, the results of the analysis and tests that were requested on April 2, 2013.

Details

1. Subject : Skin Corrosion Test

Test Substance Name : umo Concentrated Solution

Test Number : STI284

2. Test Results : As shown in the attached materials.

3. Report : Final Report (Japanese); 1 copy

Skin Corrosion Test

Study No.: STI284

Non-GLP Study

Test Report

Title: Skin Corrosion Test of umo Concentrated Solution on Rabbit Skin

Test Sponsor: APA Corporation Co., Ltd.

1. Results of Skin Corrosion / Irritation Test

2. Test Schedule

(1) Skin Application Date: April 8, 2013

(2) Observation End Date: April 15, 2013

3. Test Substance

(1) Name : umo Concentrated Solution

(2) Lot Number : UN-546

(3) Purity : 100%

(4) Appearance : Colorless and transparent liquid

(5) Components : Sodium silicate and water

(6) Supplier : APA Corporation Co., Ltd.

4. Test Animals

(1) Species, strain, sex : Rabbit, Kbs:NZW (Healthy), Male

(2) Supplier : Kitayama Labes Co., Ltd.

(3) Date of Receipt : January 24, 2013

(4) Age at Receipt : 13 weeks

(5) Quarantine Period : 14 days

(6) Age at Application : 23 weeks

(7) Number of Animals Used : 3

(8) Body Weight at Application : 3025.1 g – 3360.8 g

(9) Animal Identification : Numbers written on rabbit ears using oil-based ink

5. Housing Conditions

(1) Housing Method:Animals were housed individually in suspended cages with stainless-steel mesh floors and aluminum walls (W590 × D636 × H430 mm, CLEA Japan, Inc.). Cages were replaced with washed and sterilized cages once every two weeks.

(2) Feed and Water:Approximately 120 g/day of solid rabbit feed (LRC4, Oriental Yeast Co., Ltd.) was provided. Tap water was supplied ad libitum via an automatic watering system (Lab Engineering Co., Ltd.).

(3) Environmental Conditions:Temperature: 20–24°CRelative humidity: 30–70%Lighting: 12 hours (08:00–20:00)Ventilation: 10 air changes per hour

6. Test Method (Reference: OECD Test Guideline 404¹)

(1) Application

① Applied dose: 0.5 mL / 2.5 cm × 2.5 cm / 1 site

② Vehicle (amount): None

③ Application method:The dorsal area was shaved, and the test substance was applied to lint cloth (Nisshin Medical Instruments Co., Ltd.) (2.5 cm × 2.5 cm). The cloth was applied occlusively to the dorsal skin for 3 minutes, 1 hour, and 4 hours (3 sites).

(2) Removal of Test Substance

After removal of the patch, the application site was wiped with absorbent cotton soaked in tap water to remove the test substance.

(3) Observation Times

1, 24, 48, and 72 hours after removal of the test substance, and 1 week after removal.

(4) Evaluation of Irritation

Observations were conducted according to the evaluation criteria of Draize² (Appendix 1), and the Primary Irritation Index (P.I.I.) was calculated to evaluate skin irritation. Based on the obtained results, classification under GHS³ (Appendix 2) was also determined, and the presence or absence of irreversible reactions was assessed.

7. Results

(1) Findings:The intensity of local reactions of rabbit skin to umo Concentrated Solution (3-minute exposure, 1-hour exposure, and 4-hour exposure) is shown in Table 1, Table 2, and Table 3, respectively.

(2) Primary Irritation Index (P.I.I.):3-minute exposure: 01-hour exposure: 0.14-hour exposure: 0.9

(3) Final Evaluation

① Draize² evaluation: Slight irritation observed

② GHS³ classification: Not applicable to skin corrosion/irritation classification; Not classified

8. References

OECD; Guidelines for the Testing of Chemicals, 404 Acute Dermal Irritation/Corrosion (2002)
Draize, J.H., Woodard, G., and Calvery, H.O.; Journal of Pharmacology and Experimental Therapeutics, 82, 377–390 (1944)
United Nations GHS Document: Globally Harmonized System of Classification and Labelling of Chemicals (GHS),Part 3, Chapter 3.2: Skin Corrosion/Irritation (4th revised edition, 2011)

9. Data Retention

All materials related to this test will be retained for five years from the report preparation date.

Approval Date: April 25, 2013

Table 1

Intensity of Local Skin Reactions in Rabbits Treated with umo Concentrated Solution (3-minute exposure)

Primary Irritation Index: 0(Sum of local reaction scores up to 72 hours / 12)

Table 2

Intensity of Local Skin Reactions in Rabbits Treated with umo Concentrated Solution (1-hour exposure)

Primary Irritation Index: 0.1(Sum of local reaction scores up to 72 hours / 12)

Table 3

Intensity of Local Skin Reactions in Rabbits Treated with umo Concentrated Solution (4-hour exposure)

Primary Irritation Index: 0.9(Sum of local reaction scores up to 72 hours / 12)

Final Evaluation

Draize² evaluation: Slight irritation observed

GHS³ classification: Not applicable to skin corrosion/irritation classification; Not classified

Photo 1

72 hours after removal of the test substance (Animal No. 1)

① umo Concentrated Solution (3-minute exposure)

② umo Concentrated Solution (1-hour exposure)

③ umo Concentrated Solution (4-hour exposure)

Appendix 1

Evaluation Method for Skin Irritation Test (Draize² Criteria)

1. Criteria for Evaluation of Local Reactions in Skin Irritation Tests

2. Evaluation Based on the Draize² Method

(1) The Primary Irritation Index is calculated according to the following method, referencing the original Draize² publication:

Primary Irritation Index (P.I.I.)= Total score up to 72 hours after removal /(Number of application sites × number of observations (4) × number of animals)

(2) Evaluation of the Primary Irritation Index (P.I.I.)

In addition, irreversible tissue damage (such as erosion, ulceration, hemorrhagic scab, discoloration, scarring, etc.), or lack of recovery observed during the usual 2-week observation period, shall be judged as corrosive (C).

(Note) P.I.I. = Primary Irritation Index

Appendix 2

GHS³ Classification of Skin Corrosion / Irritation

Skin Corrosion Categories
Sub-categories of Skin Corrosion
Skin Irritation Categories

※ If not classified under any of the above categories, the substance shall be classified as “Not Classified.”

Note: This paper is translated from the following URL. The content is provided for reference on the scientific research of the raw material only. Whether APA raw materials are used or not, we hope this research will help increase understanding and awareness of body minerals.