Potassium neodecanoate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-03-07 to 2018-03-09

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2015-07-28

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: ICCVAM: Corrositex: An in vitro test method for assessing dermal corrosivity potential of chemicals.

Version / remarks:

1996-06

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2015-06-05

Test material

Test material information

Constituent 1

Reference substance name:

Potassium neodecanoate

EC Number:

247-978-7

EC Name:

Potassium neodecanoate

Cas Number:

26761-42-2

Molecular formula:

C10H19KO2

IUPAC Name:

potassium 2-methylnonanoate

Test material form:

solid

Details on test material:

- State of aggregation at room temperature: solid, sticky/waxy

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: < 30 °C, dry

In vitro test system

Test system:

artificial membrane barrier model

Source species:

other: not specified

Cell type:

other: synthetic macromolecular bio-barrier

Cell source:

other: not specified

Source strain:

not specified

Details on animal used as source of test system:

not applicable

Justification for test system used:

Corrositex TM is a validated and accepted in vitro method to assess if a test item can produce skin corrosion and to distinguish between GHS corrosivity categories 1A, 1B, and 1C.

Vehicle:

unchanged (no vehicle)

Details on test system:

SOURCE AND COMPOSITION OF MEMBRANE BARRIER USED
- Was the Corrositex® test kit used: yes (lot no. CT120516, supplier: Invitro International; Irvine)
- Components: the test kit contained BIOBARRIER matrix and diluent, vials filled with CDS, confirm reagent, qualify test tubes, one tray of membrane discs
- Apparatus and preparation procedures: the preparation was completed at least 2 hours prior to running tests. The entire content of the BIOBARRIER diluent was added to the vial of BIOBARRIER matrix powder. The vial was heated to 68°C (± 1°C) in a water bath under smooth agitation. After complete dissolution (approximately 20 min.) the solution was allowed to sit for 5 min. to allow any air bubbles to rise to the surface. 200 μL of the BIOBARRIER were pipetted into each membrane disc. The BIOBARRIERS were set on the tray and kept in the cold (2 - 8°C) for at least two hours.

WAS THE COMPATIBILITY TEST PERFORMED: yes
This step ensures that the sample is compatible with the CORROSITEX™ system. 100 mg of the test substance are added to the Qualify test tube. Solids were shaken to dissolve solids, if necessary. If the colour or consistency of the CDS changes at the sample/testing fluid interface, the test material is qualified for the assay. If no reaction is observed within five minutes, the sample is not qualified for the CORROSITEX™ Assay.

WAS THE TIMESCALE CATEGORY TEST PERFORMED: yes
This step established the category of cut-off times for the sample. 100 mg of the test substance were added to the tubes labeled Tube A and Tube B. After shaking a colour change was observed in either of the tubes and colour was matched to the corresponding colour charts on the CORROSITEX™ Testing Protocol Poster. Test materials having high acid/alkaline reserves are defined as Category 1 materials, while those with low acid/alkaline reserves are defined as Category 2 materials. If no colour change had been observed in either tube, CONFIRM reagent was added to Tube B. After shaking, the resulting colour was matched to the colour chart on the CORROSITEX™ Testing Protocol Poster. If the test item has a strong inherent colour or shows other characteristics impairing a clear categorization according to the colour chart, the pH value can be measured in tubes A and B and is used to confirm/determine the category of the test item, according to the Corrositex® Reference Manual.

TEMPERATURE USED DURING TREATMENT: room temperature

METHOD OF DETECTION
- Chemical or electrochemical detection system: chemical detection system

METHOD OF APPLICATION (CLASSIFICATION TEST):
The CDS vials were warmed to room temperature (17 - 25˚C) before using. Vials 1 - 4 were utilized for sample replicate testing (test item: 4 vials; negative control: 1 vial; positive control: 1 vial; colour reference for CDS: 1 vial). One BIOBARRIER disc was added on top of the first vial (discs were not longer in the vial than two minutes before adding the test samples). 500 mg of the test item were applied evenly on the top of the BIOBARRIER disc and starting time was recorded. This step was repeated for the remaining vials, staggering each start time by e.g. 10 seconds (but not longer than 2 minutes). The start time difference for each vial was subtracted from the final time to determine the net response time. As soon as a reaction had been observed, the time was recorded.

DATA ANALYSIS:
The test item was categorised according to the criteria in table 1 as presented in the field "Any other information on materials and methods incl. tables" below. For Category 1 substances, test chemicals will be categorized as non-corrosive in case no colour change occurs after 240 minutes. For Category 2 substances, test chemicals will be categorized as non-corrosive in case no colour change occurs after 60 minutes. The mean time of the four sample replicates to activate the CDS was calculated.

TEST ACCEPTANCE CRITERIA:
The test meets acceptance criteria if:
- Test item qualifies in qualification test
- Positive control activates CDS > 3 - 60 min.
- Negative control activates CDS not before 60 min.

Control samples:

yes, concurrent negative control

yes, concurrent no treatment

other: colour reference for the chemical detection system

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): approx. 500 mg of the test item
- an application aid (nylon mesh) was used to achieve direct contact with the synthetic membrane. Compatibility of test material and nylon mesh was confirmed microscopically.

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 500 µL

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 500 µL

Duration of treatment / exposure:

60 minutes

Duration of post-treatment incubation (if applicable):

not applicable

Number of replicates:

Test item: quadruplicates
Negative control: single measurement
Positive control: single measurement

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

penetration time (in minutes)

Value:

0

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: The test substance showed no corrosive effects

Other effects / acceptance of results:

QUALIFICATION TEST
The test substance was compatible with the CORROSITEX™ Assay, as assessed in the qualification step. The categorization step and the classification step could be performed.

CATEGORISATION TEST
A direct colour change was not observed. CONFIRM reagent was added to tube B and the category was read from the CORROSITEX™ colour chart. The chemical has been categorized to category 2.

ACCEPTANCE OF RESULTS:
The test substance proved its ability to activate the CDS.

- Acceptance criteria met for negative control: the negative control did not activate the CDS before 60 min. (> 60 min.)

- Acceptance criteria met for positive control: the positive control activated the CDS between 3 - 60 min. (19.90 min.)

Any other information on results incl. tables

CLASSIFICATION TEST:

The mean time, required to activate the CDS was > 60min.

	CORROSITEX™ Time [min]	Colour Change	Consistency Change
Replicate 1	> 60	No	No
Replicate 2	> 60	No	No
Replicate 3	> 60	No	No
Replicate 4	> 60	No	No
Mean ± SD	> 60
Positive control	26.02	Yes	No
Negative control	> 60	No	No

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Potassium neodecanoate is not corrosive to the skin.
According to the Regulation (EC) No 1272/2008 and subsequent regulations, the test item is not corrosive to the skin.