N,N-bis(2,3-epoxypropyl)aniline

Endpoint summary

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

Deviations:

no

GLP compliance:

yes

Test system:

human skin model

Source species:

human

Vehicle:

unchanged (no vehicle)

Details on test system:

EPISKIN™ Reconstructed Human Epidermis Model Kit
Supplier : SkinEthic Laboratories, Lyon, France
Date received : 21 June 2016
EpiSkinTM Tissues (0.38cm2) lot number : 16-EKIN-025
Maintenance Medium lot number : 16-MAIN3-040
Assay Medium lot number : 16-ESSC-025

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

10 uL

Duration of treatment / exposure:

15 minutes

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

3

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

15 minutes

Value:

67.8

Negative controls validity:

valid

Positive controls validity:

valid

Mean OD₅₆₂ Values and Viabilities for the Negative Control Item, Positive Control Item and Test Item

Item	OD562 of tissues	Mean OD562 of triplicate tissues	± SD of OD562	Relative individual tissue viability (%)	Relative mean viability (%)	± SD of Relative mean viability (%)
Negative Control Item	0.648	0.643	0.006	100.8	100+	0.9
	0.644			100.2
	0.637			99.1
Positive Control Item	0.158	0.133	0.022	24.6	20.7	3.4
	0.118			18.4
	0.122			19.0
Test Item	0.469	0.436	0.053	72.9	67.8	9.3
	0.464			72.2
	0.374			58.2

OD = Optical Density

SD = Standard deviation

∗ = The mean viability of the negative control tissues is set at 100%

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was classified as non-irritant. The following classification criteria apply: EU CLP Not classified for Irritation. UN GHS Not classified for Irritation (category 3 can not be determined).

Executive summary:

Introduction

The purpose of this test was to evaluate the skin irritation potential of the test item using the EPISKINTM reconstructed human epidermis model after a treatment period of 15 minutes followed by a post-exposure incubation period of 42 hours. The principle of the assay was

based on the measurement of cytotoxicity in reconstructed human epidermal cultures following topical exposure to the test item by means of the colorimetric MTT reduction assay. Cell viability is measured by enzymatic reduction of the yellow MTT tetrazolium salt (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) to a blue formazan salt (within the mitochondria of viable cells) in the test item treated tissues relative to the negative controls.

Method

Triplicate tissues were treated with the test item for an exposure period of 15 minutes. At the end of the exposure period each tissue was rinsed before incubating for 42 hours. At the end of the post-exposure incubation period each tissue was taken for MTT-loading. The maintenance medium from beneath each tissue was transferred to pre-labeled micro tubes and stored in a freezer for possible inflammatory mediator determination. After MTT-loading a total biopsy of each epidermis was made and placed into micro tubes containing acidified

isopropanol for extraction of formazan crystals out of the MTT-loaded tissues. At the end of the formazan extraction period each tube was mixed thoroughly and duplicate 200 μL samples were transferred to the appropriate wells of a pre-labeled 96-well plate. The optical density was measured at 562 nm. Data are presented in the form of percentage viability (MTT reduction in the test item treated tissues relative to negative control tissues).

Results

The relative mean viability of the test item treated tissues was 67.8% after the 15-Minute exposure period and 42-Hours post-exposure incubation period.

Quality criteria: The quality criteria required for acceptance of results in the test were

satisfied.

Conclusion

The test item was classified as non-irritant. The following classification criteria apply: EU CLP Not classified for Irritation. UN GHS Not classified for Irritation (category 3 can not be determined).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)