N,N'-(3,3'-dimethylbiphenyl-4,4'-ylene)di(acetoacetamide)

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

According to: OECD Guideline for the testing of Chemicals 439: In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method (Original Guideline adopted July 26, 2013), and as described in detail in the Protocol for: In Vitro EpiDermTM Skin Irritation Test (EPI-200-SIT) for use with MatTek Corporation’s Reconstructed Human Epidermal Model EpiDerm (EPI-200), Rev. 1/19/2010

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

N,N'-(3,3'-dimethylbiphenyl-4,4'-ylene)di(acetoacetamide)

EC Number:

202-111-1

EC Name:

N,N'-(3,3'-dimethylbiphenyl-4,4'-ylene)di(acetoacetamide)

Cas Number:

91-96-3

Molecular formula:

C22H24N2O4

IUPAC Name:

N,N'-(3,3'-dimethylbiphenyl-4,4'-diyl)bis(3-oxobutanamide)

Details on test material:

Purity: 99.1%
Expiry Date: 03 June 2015

Test system

Amount / concentration applied:

Each approximately 25 mg of the neat test item were applied to three EpiDerm (MatTek) skin equivalents. Additionally, the equivalents were wetted with 25 µL DPBS.

Duration of treatment / exposure:

The skin equivalents were exposed to the neat test item for 60 minutes. After completion of the treatment the test item was rinsed off and the skin equivalents were incubated for further 43 hours.

Details on study design:

Each approximately 25 mg of the neat test item and 30 µL of the negative control (DPBS) or the positive control (5% SLS) were applied to three EpiDerm (MatTek) skin equivalents. Additionally, the test item treated tissues were wetted with each 25 µL DPBS. The test item as well as the controls were rinsed off the tissues after 60 minutes treatment. After further 43 hours incubation the tissues were treated with the MTT solution for 3 hours following approximately 70 hours extraction of the colorant from the cells. The amount of extracted colorant was detemrined photometrically at a wavelength of 570 nm.

Results and discussion

In vivo

Irritant / corrosive response data:

Compared to the relative absorbance value of the negative control the mean relative absorbance value decreased to 95.4% after exposure of the test item to the skin tissues. This value is well above the threshold for irritancy of ≤ 50%. Therefore, the test item is not considered to possess an irritant potential.

Any other information on results incl. tables

Results after treatment with Naphtol AS-G trocken and the controls

Dose Group	Treat-ment Interval	Absorbance 570 nm Tissue 1*	Absorbance 570 nm Tissue 2*	Absorbance 570 nm Tissue 3*	Mean Absorbance of 3 Tissues	Rel. Absorbance [%] Tissue 1, 2 + 3**	Relative Standard Deviation [%]	Mean Rel. Absorbance [% of Negative Control]***
Nega-tive Control	60 min	1.781	1.788	1.842	1.803	98.7 99.1 102.1	1.8	100.0
Positive Control	60 min	0.054	0.056	0.064	0.058	3.0 3.1 3.6	9.5	3.2
Test Item	60 min	1.698	1.647	1.819	1.721	94.1 91.3 100.9	5.1	95.4

 

*      Mean of three replicate wells after blank correction
**       relative absorbance per tissue [rounded values]
***     relative absorbance per treatment group [rounded values]

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

In conclusion, it can be stated that in this study and under the experimental conditions reported, Naphtol AS-G trocken is not irritant to skin.

Executive summary:

This in vitro study was performed to assess the irritation potential of Naphtol AS-G trocken by means of the Human Skin Model Test.

Each three tissues of the human skin model EpiDerm^™were treated with the test item, the negative or the positive control for 60 minutes.

About 25 mg of the test item were applied to each tissue, wetted with DPBS, and spread to match the tissue surface.

30 µL of either the negative control (DPBS) or the positive control (5% Sodium lauryl sulfate) were applied to each tissue.

The test item and the positive and negative controls were washed off the skin tissues after 60 minutes treatment. After further incubation for about 43 hours the tissues were treated with the MTT solution for 3 hours following ~ 69.5 hours extraction of the colorant from the cells. The amount of extracted colorant was determined photometrically at 570 nm.

After treatment with the negative control the absorbance values were well within the required acceptability criterion of mean OD greater or equal than 0.8 and less or equal 2.8 for the 60 minutes treatment interval thus showing the quality of the tissues.

Treatment with the positive control induced a decrease in the relative absorbance as compared to the negative control to 3.2% thus ensuring the validity of the test system.

The standard deviations between the % variabilities of the test item, the positive and negative controls were below 10% (threshold of the "OECD Guideline for the Testing of Chemicals 439: In vitro Skin Irritation: Reconstructed Human Epidermis Test Method”: 18%), thus ensuring the validity of the study.

Compared to the relative absorbance value of the negative controlthe mean relative absorbance value decreased to 95.4% after exposure of the test item to the skin tissues. This value is well above the threshold for irritancy of ≤ 50%. Therefore, the test item is not considered to possess an irritant potential.