Registration Dossier

Toxicological information

Skin irritation / corrosion

Currently viewing:

Administrative data

Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2011
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to OECD guidelines No. 439 “In Vitro Skin Irritation” and in accordance with GLP.
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2011
Report Date:
2011

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: OECD guidelines No. 439 “In Vitro Skin Irritation”
Principles of method if other than guideline:
Guideline followed.
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report)
- Physical state: White powder
- Analytical purity: 99.5%
- Storage condition of test material: Room temperature in the dark.

Test animals

Species:
other: EPISKIN reconstructed human epidermis model
Strain:
other: EPISKIN reconstructed human epidermis model
Details on test animals and environmental conditions:
The EPISKIN model is a three-dimensional reconstructed human epidermis model consisting of adult human-derived epidermal keratinocytes seededon a dermal substitute consisting of a collagen type I matrix coated with type IV collagen. A highly differentiated and stratified epidermis model is obtained after a 13-day culture period comprising of the main basal, supra basal, spinous and granular layers and a functional stratum corneum.

Test system

Type of coverage:
other: In vitro - reconstructed human epidermis model
Preparation of test site:
other: reconstructed human epidermis model
Vehicle:
unchanged (no vehicle)
Controls:
other: Negative and positive controls maintained
Amount / concentration applied:
10 mg
Duration of treatment / exposure:
15 min
Observation period:
42 hour post-exposure incubation period.
Number of animals:
Triplicate tissues were treated.
Details on study design:
Triplicate tissues were treated with the test item for an exposure period of 15 minutes. At the end of the exposure period each tissue was rinsed before incubating for 42 hours. At the end of the post-exposure incubation period each tissue was taken for MTT-loading. The maintenance medium from beneath each tissue was transferred to pre-labelled micro tubes and stored in a freezer for possible inflammatory mediator determination. After MTT loading a total biopsy of each epidermis was made and placed into micro tubes containing acidified isopropanol for extraction of extraction of formazan crystals out of the MTT-loaded tissues.
At the end of the formazan extraction period each tube was mixed thoroughly and duplicate 200 microliter samples were transferred to the appropriate wells of a pre-labelled 96-well plate. The optical density was measured at 540 nm. Data are presented in the form of percentage viability (MTT reduction in the test item treated tissues relative to negative control tissues).

Results and discussion

In vitro

Results
Irritation / corrosion parameter:
other: other: relative mean tissue viability
Remarks on result:
other:
Remarks:
Basis: mean. Time point: 15 minute exposure period. Max. score: 100.8. Reversibility: other: Not applicable - In vitro testing. Remarks: End point expressed as %. (migrated information)

In vivo

Irritant / corrosive response data:
The relative mean tissue viability of the test item treated tissues was 100.8% after a 15-minute exposure period.

The relative mean tissue viability for the positive control treated tissues was 6.2% relative to the negative control treated tissues and the standard deviation value of the percentage viability was 2.2%. The positive control acceptance criterion was therefore satisfied.

The mean OD 540 for the negative control treated tissues was 0.826 and the standard deviation value of the percentage viability was 2.7%. The negative control acceptance criterion was therefore satisfied.

The standard deviation calculated from individual percentage tissue viabilities of the three identically treated tissues was 3.4%. The test item acceptance criterion was therefore satisfied.
Other effects:
None

Any other information on results incl. tables

None

Applicant's summary and conclusion

Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The test item was considered to be Non-Irritant.
Executive summary:

The purpose of this test was to evaluate the skin irritation potential of the test item using EPISKIN reconstructed human epidermis model after a treatment period of 15 minutes followed by a post-exposure incubation period of 42 hours. The method followed was similar to OECD TG No.439. Triplicate tissues were treated with the test item for an exposure period of 15 minutes. At the end of the exposure period each tissue was rinsed before incubating for 42 hours. At the end of the post-exposure incubation period each tissue was taken for MTT-loading. The maintenance medium from beneath each tissue was transferred to pre-labelled micro tubes and stored in a freezer for possible inflammatory mediator determination. After MTT loading a total biopsy of each epidermis was made and placed into micro tubes containing acidified isopropanol for extraction of extraction of formazan crystals out of the MTT-loaded tissues.

At the end of the formazan extraction period each tube was mixed thoroughly and duplicate 200 microliter samples were transferred to the appropriate wells of a pre-labelled 96-well plate. The optical density was measured at 540 nm. Data are presented in the form of percentage viability (MTT reduction in the test item treated tissues relative to negative control tissues).

Results: The relative mean viability of the test item treated tissues was 100.8% after the 15-minute exposure period.

CONCLUSION: The test item was considered to be Non-Irritant.