Saccharomyces cerevisiae, ext.

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation / corrosion, other

Remarks:

other: OECD 439 In vitro

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12-Jul-2010 to 19-Jul-2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: EU method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: OECD Guidelines for Testing of Chemicals, Guideline no. 439: In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Saccharomyces cerevisiae, ext.

EC Number:

283-294-5

EC Name:

Saccharomyces cerevisiae, ext.

Cas Number:

84604-16-0

Molecular formula:

Not applicable as the substance is an UVCB

IUPAC Name:

Yeast extract, Saccharomyces cerevisiae

Constituent 2

Reference substance name:

Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L)

IUPAC Name:

Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L)

Details on test material:

- Name of test material (as cited in study report): Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L)
- Substance type: Light beige powder
- Physical state: Powder
- Stability under test conditions: Stable
- Storage condition of test material: At room temperature in the dark

Test system

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10 mg, moistened with 5 µl water

NEGATIVE CONTOL:
- Amount(s) applied (volume or weight with unit): 10 µl Phosphate buffered saline

POSITIVE CONTROL
- Amount(s) applied (volume or weight with unit): 10 µl
- Concentration (if solution): 5% (aq) Sodium dodecyl sulphate

Duration of treatment / exposure:

Exposure:15 minutes
Post incubation period: 42 hours

Details on study design:

TEST SITE
- Area of exposure: human epidermis model
- % coverage: 0.38 cm2

REMOVAL OF TEST SUBSTANCE
- Washing (if done): phosphate buffered saline
- Time after start of exposure: 15 minutes

POST INCUBATION PERIOD
- 42 hours

SCORING SYSTEM:
- After a 42 hour incubation period, determination of the cytotoxic (irritancy) effect was performed. Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT at the end of the treatment. Cell viability was calculated for each tissue as a percentage of the mean of the negative control tissues. In addition to the normal procedure, three killed tissues treated with test substance and three killed non treated tissues were used for the cytotoxicity evaluation with MTT.

Results and discussion

In vivo

Results

Irritation parameter:

other: percentage viability

Basis:

other: percentage of control

Time point:

other: 15 minutes

Score:

108

Irritant / corrosive response data:

The non-specific reduction of MTT by Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) was 0.33% of the negative control tissues. The net OD of the treated killed tissues was subtracted from the ODs of the test substance treated viable tissues.

Other effects:

Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) was checked for possible direct MTT reduction by adding the test substance to MTT medium. Because a colour change was observed it was concluded that Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) did interact with MTT.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information

Conclusions:

The positive and negative controls were within the historical control data.

Skin irritation is expressed as the remaining cell viability after exposure to the test substance. The relative mean tissue viability obtained after 15 minutes treatment with Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) compared to the negative control tissues was 108%. Since the mean relative tissue viability for Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) was above 50% after 15 minutes treatment Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) is considered to be non-irritant.

Finally, it is concluded that this test is valid and that Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) is non-irritant in the in vitro skin irritation test under the experimental conditions described in the report.

Executive summary:

The ability of Saccharomyces cerevisiae, Extract (Springer 0207/0 -MG-L) to induce skin irritation on a human three dimensional epidermal model (EPISKIN Standard model (EPISKIN-SM^TM)) was tested. The possible skin irritation potential was tested through topical application for 15 minutes.

Saccharomyces cerevisiae, Extract (Springer 0207/0 -MG-L) did interact with

3 -(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). In addition to the normal procedure, three killed tissues treated with test substance and three killed non-treated tissues were used for the cytotoxicity evaluation with MTT. The non-specific reduction of MTT by Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) was 0.33% of the negative control tissues. The net OD of the treated killed tissues was subtracted from the ODs of the test substance treated viable tissues.

Skin irritation is expressed as the remaining cell viability after exposure to the test substance. The relative mean tissue viability obtained after 15 minutes treatment with Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) compared to the negative control tissues was 108%. Since the mean relative tissue viability for Saccharomyces cerevisiae, Extract

(Springer 0207/0 -MG-L) was above 50% after 15 minutes treatment Saccharomyces cerevisiae, Extract (Springer 0207/0-MG-L) is considered to be non-irritant.

The positive control had a mean cell viability of 8% after 15 minutes exposure. The absolute mean OD₅₇₀(optical density at 570 nm) of the negative control tissues was within the laboratory historical control data range. The standard deviation value of the percentage viability of three tissues treated identically was less than 18%, indicating that the test system functioned properly.