Decanoic acid, mixed esters with heptanoic acid, isovaleric acid, octanoic acid and pentaerythritol

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Remarks:

in vitro

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03 April 2014 to 02 July 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed in accordance with OECD test guidelines in compliance with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Human Skin Model Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPA 40 CFR 158.340

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Decanoic acid, mixed esters with heptanoic acid, octanoic acid and trimethylolpropane

EC Number:

268-596-7

EC Name:

Decanoic acid, mixed esters with heptanoic acid, octanoic acid and trimethylolpropane

Cas Number:

68130-53-0

Molecular formula:

not available due to the complexity of the substance

IUPAC Name:

Decanoic acid, heptanoic acid and octanoic acid, mixed esters with trimethylolpropane

Test material form:

other: liquid

Details on test material:

Identity: H2925 (CAS No 68130-53-0), Lot# 2013090401
Provided by: Chemtura Corporation
Date Received: 18 Mar 2014
Storage: Room temperature and humidity.
Description: Clear yellow liquid
Sample Preparation: Used as received.

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: Not specified

Source strain:

not specified

Details on animal used as source of test system:

EpiDerm™ tissues, Lot 19981 Kit D, were received from MatTek Corporation (Ashland, MA) on 08 Apr 2014 and refrigerated at approximately 4'C. Before use, tissues were incubated (37°C ± 1°C, 5% ± 1% CO2) with assay medium (MatTek) for a one-hour equilibration. Equilibration medium was replaced with fresh medium before dosing.

Justification for test system used:

In accordance with the test guidelines.

Vehicle:

unchanged (no vehicle)

Details on test system:

Test Article Reduction of MTT: 100 µI of the test article were mixed with 1 ml of MTT solution (1 mg/ml Methyl thiazole tetrazolium diluted in Dulbecco's Modified Eagle's Medium (DMEM)). A Negative Control, 100 µI of tissue culture water, was tested concurrently. The solutions were incubated at room temperature in the dark for 60 minutes. After incubation, the solutions were visually inspected for purple coloration, which indicates that the test article reduced MTT. Since tissue Viability is based on MTT reduction, direct reduction by a test article can exaggerate viability, making a test article seem less irritating than it really is. The test article did not reduce MTT and the assay continued as per the protocol.

Mesh Compatibility: Pre-cut nylon meshes supplied with the tissues were placed on a slide and 30 µI of the test article or tissue culture water were applied. After 60 minutes exposure, the mesh was checked microscopically. No interaction between the test article or tissue culture water and the mesh was observed so the test article was dosed using the mesh as a spreading aid.

Dosing: 50 µI of the test article were applied to the top of each EpiDerm™ tissue. A nylon mesh was then placed on top to facilitate even distribution of the test article. The test article remained in contact with the EpiDerm™ tissue for 3 and 60 minutes. A Negative Control (TCH2O) and a Positive Control (KOH) were tested at 3 and 60 minutes. A nylon mesh was placed on top of each liquid control to facilitate even distribution of the material. Each treatment with test article or control was conducted in duplicate.
All tissues were dosed at ambient temperature. Tissues treated with the test article and controls for 3 minutes were maintained at ambient temperature until analyzed for Tissue Viability (MTT Reduction). Tissues to be treated for 60 minutes were dosed and then returned to the Incubator (37°C ± 1°C, 5% ± 1% CO2) for the remainder of the 60-minute exposure period

Tissue Viability (MTT Reduction): At the end of the exposure period, each EpiDerm™ tissue was rinsed with phosphate buffered saline (PBS) and transferred to a 24-well plate containing 300 µI of MTT solution (1 mg/ml MTT in DMEM). The tissues were then returned to the Incubator for a three-hour MTT incubation period. Following the MTT incubation period, each EpiDerm™ tissue was rinsed with PBS and then treated overnight with 2.0 ml of extractant solution (isopropanol) per well. The absorbency of an aliquot of the extracted MTT formazan was measured In triplicate at 540 nm using a microplate reader (µQuant Plate Reader, BioTek Instruments, Winooski, VT).

Analysis of Data: The mean absorbance value for each time point was calculated from the optical density (OD) of the duplicate tissues and expressed as percent viability for each sample using the following formula:
% viability = 100 X (OD sample/OD Negative Control)

Quality Controls: The Negative Controls meets the acceptance criterion if the mean OD of the two tissues at each time point is greater than or equal to 0.8 and is less than or equal to 2.8 (0.8 ≤ OD ≤ 2.8).
The Positive Control meets the acceptance criterion If the mean relative tissue viability at the 60 minute time point is less than 15% < 15%).
Inter-tissue viability meets the acceptance criterion if the difference between two identically treated tissues is no greater than 30%. Re-testing of the chemical is recommended if the resulting viability is near to a classification cut-off. Note: If necessary, the percent difference will be calculated between the mean of the two tissues and one of the tissues. If this difference is greater than 15%, then rejection should be considered.

Interpretation of Results: Skin Corrosion is defined as the production of irreversible tissue damage in skin following the application of test material. The percent viability calculated was used to determine corrosivity potential in the following manner:
Mean Viability Mean Viability
(3 min.) (60 min.) Predicted Corrosivity
<50% Not Applicable Corrosive
≥50% <15% Corrosive
≥50% ≥15% Non-Corrosive

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

50 µI of the test article were applied to the top of each EpiDerm™ tissue.

Duration of treatment / exposure:

3 and 60 minutes

Duration of post-treatment incubation (if applicable):

Not specified

Number of replicates:

Tests were repeated in triplicate.

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 minute exposure

Value:

85.2

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 minute exposure

Value:

100

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

EXPERIMENTAL DATA

Test Article:		H2925 (CAS No. 68130-53-0), Lot# 2013090401
Dose:		50µl
Conc:		Neat
TIME (min)	OD 1	OD 2	OD 3	MEAN (OD)	SD	VIABILITY %	ERROR %
3.0	1.824	1.833	1.837	1.831	0.007	89.1	0.3
	1.670	1.679	1.671	1.673	0.005	81.4	0.2
Neg control				2.056		100.0
60.0	1.725	1.721	1.717	1.721	0.004	89.4	0.2
	2.112	2.153	2.135	2.133	0.021	110.9	1.1
Neg control				1.924		100.0
Mean % Viability at 3 min:						85.2
Mean % Viability at 60 min:						100.1
Predicted Corrosivity:			Non-corrosive

 

Negative Control:		Tissue Culture Water
Dose:		50µl
Conc:		Neat
TIME (min)	OD 1	OD 2	OD 3	MEAN (OD)	SD	VIABILITY %	ERROR %
3.0	2.026	2.078	2.066	2.057	0.027	100.0	1.3
3.0	2.00	2.073	2.094	2.056	0.049	100.0	2.4
Mean				2.056		100.0
60.0	1.959	1.936	1.961	1.952	0.014	101.4	0.7
60.0	1.859	1.932	1.899	1.897	0.037	98.6	1.9
Mean				1.924		100.0
Predicted Corrosivity:			Non-corrosive

 

Positive Control:		Potassium Hydroxide, 8.0 N
Dose:		50µl
Conc:		Neat
TIME (min)	OD 1	OD 2	OD 3	MEAN (OD)	SD	VIABILITY %	ERROR %
3.0	0.587	0.602	0.602	0.597	0.009	29.0	0.4
3.0	0.705	0.708	0.708	0.707	0.002	34.4	0.1
Neg control				2.056		100.0
60.0	0.038	0.039	0.040	0.039	0.001	2.0	0.1
60.0	0.043	0.043	0.043	0.043	0.000	2.2	0.0
Neg control				1.924		100.0
Mean % Viability at 3 min:						31.7
Mean % Viability at 60 min:						2.1
Predicted Corrosivity:			Corrosive

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

H2925 (CAS No. 68130-53-0), Lot# 2013090401 is predicted to be non-corrosive.

Executive summary:

OBJECTIVE: To predict and classify the skin corrosivity potential of a chemical by using a three-dimensional human epidermis model. This study is designed based on MatTek protocol "In Vitro EpiDerm™ Skin Corrosion Test" and follows the OECD Guideline for the Testing of Chemicals No. 431 In Vitro Skin Corrosion: Human Skin Model Test.

METHOD SYNOPSIS: MatTek EpiDerm^TMtissues were treated in duplicate with the test article. Negative Control and Positive Control for 3 minutes and 60 minutes. Following treatment, the viability of thetissues was determined using Methyl thiazole tetrazolium (MTT) uptake and conversion, and theabsorbance of each tissue was measured at 540 nm. The mean viability was then expressed as apercent of control values. The percent viability was used to determine corrosivity potential.

 

SUMMARY/CONCLUSION:

Test and Control Article Identity	Mean Viability (3 min.)	Mean Viability (60 min.)	Predicted Corrosivity
H2925 (CAS No. 68130-53-0), Lot# 2013090401	85.2%	100.1%	Non-Corrosive
Tissue culture water (Negative Control)	100.0%	100.0%	Non-Corrosive
Potassium Hydroxide, 8.0 N (Positive Control)	31.7%	2.1%	Corrosive