4-methylpent-1-ene

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation / corrosion

Remarks:

in vitro

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011-05-31 to 2011-06-02

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 431 (In vitro skin corrosion: human skin model test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.40 (In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of inspection 2010-07-20; Date of signature 2010-10-29

Test material

Test material information

Constituent 1

Reference substance name:

4-methylpent-1-ene

EC Number:

211-720-1

EC Name:

4-methylpent-1-ene

Cas Number:

691-37-2

Molecular formula:

C6H12

IUPAC Name:

4-methylpent-1-ene

Details on test material:

- Name of test material (as cited in study report): 4-methylpent-1-ene
- Physical state: clear colourless liquid
- Analytical purity: ≥ 97 %
- Lot/batch No.: H1130311
- Date received: 2011-04-11
- Expiration date of the lot/batch: 2011-10-11
- Storage condition of test material: approximately 4 degrees Centigrade in the dark

Test animals

Species:

other: not applicable

Strain:

not specified

Details on test animals or test system and environmental conditions:

The Episkin model is a three-dimensional reconstructed human epidermis model consisting of adult human-derived epidermal keratinocytes seeded on a dermal substitute consisting of a collagen type I matrix loaded with type IV collagen. A highly differentiated and stratified epidermis model is obtained after a 13-day culture period comprising the main basal, supra basal, spinous and granular layers and a functional stratum corneum.

Test system

Type of coverage:

other: not applicable

Preparation of test site:

other: not applicable

Vehicle:

other: not applicable

Controls:

other: not applicable

Amount / concentration applied:

50 μL

Duration of treatment / exposure:

3, 60 and 240 minutes

Observation period:

Not applicable

Number of animals:

Not applicable

Details on study design:

METHOD
- The test is based on the experience that corrosive chemicals are cytotoxic after a short term exposure to the Episkin model. Corrosive chemicals are able to penetrate the stratum corneum and are sufficiently cytotoxic to cause cell death in the underlying cell layers. Toxicity is determined by the metabolic conversion of the vital dye MTT to formazan by viable cells in the test item treated relative to the negative control.
- The test material was applied topically to the stratum corneum, at the air interface, so that undiluted and/or end use dilutions could be tested directly.

ASSESSMENT OF DIRECT TEST ITEM REDUCTION OF MTT
- The MTT assay is a colourmetric method of determining cell viability based on reduction of the yellow tetrazolium salt (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) to a blue formazan dye by mitochondrial succinate dehydrogenase in viable cells.
- A known limitation of the assay is that test materials may interfere with the MTT endpoint if they are directly reduce MTT and, at the same time, are present on or in the tissues when the MTT viability test is performed. To identify any possible interference, the test item was checked for the ability to reduce MTT.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

other: relative viability of test material treated tissue

Basis:

mean

Time point:

other: 3 minutes

Score:

131.2

Remarks on result:

other: Percent

Results 2

Irritation parameter:

other: relative viability of test material treated tissue

Basis:

mean

Time point:

other: 60 minutes

Score:

141.5

Remarks on result:

other: Percent

Results 3

Irritation parameter:

other: relative viability of test material treated tissue

Basis:

mean

Time point:

other: 240 minutes

Score:

107.3

Remarks on result:

other: Percent

Irritant / corrosive response data:

The corrosivity potential of the test material was predicted from the relative mean tissue viabilities obtained after 3, 60 and 240 minute treatments, compared to the mean of the neagative control tissues (n = 2) treated with 0.9 % sodium chloride solution. The relative mean viabilities were calculated as shown below:

Relative mean viability (%) = (Mean OD540 of test material / Mean OD540 of negative control) * 100

Any other information on results incl. tables

DIRECT MTT REDUCTION

- The MTT solution containing the test material did not turn blue. This was taken to indicate that the test item did not reduce MTT.

 

TEST MATERIAL, POSITIVE CONTROL AND NEGATIVE CONTROL

- Mean OD540 values and viabilities are provided in Table 1 (attached) for the negative control, positive control and test material.

 

QUALITY CRITERIA

- The relative mean tissue viability for the positive control treated tissues was 2.4 % relative to the negative control treated tissues after 240 minutes. The positive control acceptance criterion was therefore satisfied.

- The mean OD540 for the negative control treated tissues was 0.205. The negative control acceptance criterion was therefore satisfied.

 

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Remarks:

Migrated information

Conclusions:

The test material was considered to be non-corrosive to skin.