N-[(1,1,3,3-tetramethylbutyl)phenyl]naphthalen-1-amine

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

14 Feb 2012 - 06 Mar 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

Version / remarks:

(2009)

Test guideline 3

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Remarks:

BASF SE, Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany

Test material

Test material information

Constituent 1

Reference substance name:

N-[(1,1,3,3-tetramethylbutyl)phenyl]naphthalen-1-amine

EC Number:

257-406-8

EC Name:

N-[(1,1,3,3-tetramethylbutyl)phenyl]naphthalen-1-amine

Cas Number:

51772-35-1

Molecular formula:

C24H29N

IUPAC Name:

N-[(1,1,3,3-tetramethylbutyl)phenyl]naphthalen-1-amine

Details on test material:

- Physical state: solid/white
- Analytical purity: 99.0 g/100 g determined by 1H-MR spectroscopy
- Expiration date of the lot/batch: July 15, 2015
- Storage condition of test material: Room temperature; avoid temperatures > 35°C

In vitro test system

Test system:

human skin model

Remarks:

reconstructed three dimensional human epidermis model (EpiDerm™)

Source species:

human

Cell type:

non-transformed keratinocytes

Vehicle:

other: minimally moistened with PBS

Details on test system:

EpiDerm TM 200 kit: MatTek ln Vitro Life Science Laboratories, Bratislava, Slovakia containing: 24 Epi-200 tissues (reconstructed epidermis): surface 0.6 cm² cultured in Millicells® 0 1 cm
Tissue for MTTreduction control: Epi-200 tissue that is killed by freezing at -20°C
Assay medium: Dulbecco's modified eagle's medium (DMEM); for the assay and for diluting MTT
Wash buffer: Dulbecco's phosphate buffered saline (P8S), w/o Ca2+ , Mg2+
Extracting agent: lsopropanol p.a.
Detection agent: 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT), 1.0 mg I ml assay medium

Amount/concentration applied:

25 μL de-ionized water was applied first. Thereafter, a bulk volume of 25 μL of the solid test material was applied with a sharp spoon and homogeneously distributed with the water.

Duration of treatment / exposure:

1h

Number of replicates:

three tissue samples used each for test sample and controls

Test animals

Details on test animals or test system and environmental conditions:

N/A

Test system

Controls:

other: Control tissue used for positive and negative controls

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Remarks:

mean value of three tissues

Run / experiment:

assay with the test article

Value:

102

Vehicle controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Any other information on results incl. tables

Results

Test material		Tissue 1	Tissue 2	Tissue 3	mean	SD
negative control (NC)	mean OD570	1.824	2.069	1.717	1.87
	viability [% of NC]	97.5	110.7	91.8	100	9.67
test article	mean OD570	1.735	2.068	1.911	1.905
	viability [% of NC]	92.8	110.6	102.2	102	8.92
positive control (PC)	mean OD570	0.165	0.168	0.171	0.168
	viability [% of NC]	8.8	9	9.1	9	0.17

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the observed results it was concluded, that the test substance does not show a skin irritation potential in the EpiDerm(TM) irritation test under the test conditions chosen.

Executive summary:

The test article's potential to cause dermal irritation was assessed in an in vitro irritation test according to OECD guideline 439 and in compliance with GLP. To that end, a single topical application of 25 μL bulk volume (about 14 mg) of the test substance to a reconstructed three dimensional human epidermis model (EpiDerm™) was analyzed. Three EpiDerm™ tissue samples were incubated with the test substance for 1 hour followed by a 42-hours post-incubation period. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/ post-incubation using a colorimetric test. The reduction of mitochondrial dehydrogenase activity, measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the testsubstance treated epidermal tissues is compared to that of negative control tissues. The quotient of both values indicates the relative tissue viability. The EpiDerm skin irritation test showed the following results: The test substance is not able to reduce MTT directly. The mean viability of the test-substance treated tissues determined after an exposure period of 1 hour with about 42 hours post-incubation was 102%. Based on the observed results it was concluded, that the test substance does not show a skin irritation potential in the EpiDerm™ skin irritation test under the test conditions chosen.