Potassium 2-methylbutan-2-olate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

09.09.2015 to 26.11.2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted in compliance with OECD guidline TG 435, well documented.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 435 (In Vitro Membrane Barrier Test Method for Skin Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Potassium 2-methylbutan-2-olate

EC Number:

255-272-5

EC Name:

Potassium 2-methylbutan-2-olate

Cas Number:

41233-93-6

Molecular formula:

C5H12O.K

IUPAC Name:

potassium 2-methylbutan-2-olate

Test material form:

other: solid

Test animals

Species:

other: Corrositex® kit

Strain:

other: reconstituted collagen matrix

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: control vials with positive and negative control

Amount / concentration applied:

The test substance was applied undiluted. Approximately an amount of 500 mg of the test substance was added onto the membrane disc, which was placed into one vial containing the CDS.

Duration of treatment / exposure:

The time after the application of the test substance is recorded until the first change in the indicator solution occurs (i.e. barrier penetration) .

Observation period:

The vial is observed for three minutes for any change in the CDS

Number of animals:

other: 4 vails

Details on study design:

The Corrositex® assay is a standardized in vitro corrosion test. The Corrositex® assay kit is
commercially available from InVitro International.
The Corrositex® Biobarrier Membrane is a test system consisting of a reconstituted collagen
matrix. The assay is based on the time that is required for the test substance to penetrate
through the Corrositex® Biobarrier Membrane and produce a change in the Chemical Detection
System (CDS).
The Corrositex® assay is used to determine the corrosive potential of test substances. The
assay is limited to testing those materials which cause detectable pH changes in the CDS.

The experimental design of this study consisted of a qualification screen with the CDS (to
determine if a color change can be detected) and a categorization screen (to categorize weak
acids/bases and strong acids/bases), which were performed as a pretest (experimental
conduct in accordance with GLP but without a GLP status), and a definitive Corrositex® assay.
The Corrositex® assay was evaluated on the basis of the color change of the CDS. The time
that a color change was observed was recorded manually and the breakthrough times of the
four replicates was used to determine the corrosive potential of the test substance.

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

other: overall irritation score

Remarks on result:

other:

Remarks:

Basis: mean. Time point: 24 s. Remarks: mean breakthrough time. (migrated information)

In vivo

Irritant / corrosive response data:

The mean breakthrough time of the test substance determined in the in vitro membrane barrier test was ca. 24 seconds.

Any other information on results incl. tables

Evaluation scheme:

	Time required for CDS change^1
Category 1	≤ 3 min	> 3 min ≤ 1 h	>1 h ≤ 4 h	> 4 h
Category 2	≤ 3 min	>3 ≤ 30 min	> 30 ≤ 60 min	> 60 min
Corrosive potential	corrosive^2	corrosive^3	corrosive^4	non corrosive^5

¹Occasionally, break through times may overlap the borderline between corrosive potential assignment

columns. If the break through times from 2 or more vials indicate a more severe corrosive potential, this

subcategory was assigned to the test material.

²This break through time indicates that the test substance has an extreme corrosive potential and should be

assigned to UN GHS skin corrosivity subcategories 1A or UN Transport Packing Group I as specified in OECD

TG 435 (adopted 19 July 2006) and the test system manufacturer.

³This break through time indicates that the test substance has an intermediate corrosive potential and should

be assigned to UN GHS skin corrosivity subcategories 1B or UN Transport Packing Group II as specified in

OECD TG 435 (adopted 19 July 2006) and the test system manufacturer.

⁴This break through time indicates that the test substance has a weak corrosive potential and should be

assigned to UN GHS skin corrosivity subcategories 1C or UN Transport Packing Group III as specified in OECD

TG 435 (adopted 19 July 2006) and the test system manufacturer.

⁵This break through time indicates that the test substance does not have a corrosive potential. The result does

not exclude an irritation potential of the test substance as specified in OECD TG 435 (adopted 19 July 2006)

and the test system manufacturer.

Applicant's summary and conclusion

Interpretation of results:

Category 1A (corrosive)

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Based on the observed results and applying the evaluation criteria cited it was concluded, that the test substance shows a corrosive potential in the
Corrositex® - Skin Corrosion Test under the test conditions chosen. The mean breakthrough time determined in the in vitro membrane barrier test was ca. 24 seconds. The breakthrough time indicates that the test substance has an extreme corrosive potential and should be
assigned to UN GHS skin corrosivity subcategories 1A as specified in the cited OECD TG 435.