Docosyl acrylate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2011-10-25 to 2011-11-07

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

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

July 22, 2010 (“In vitro Skin Irritation: Reconstructed Human Epidermis Test Method”)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

BASF SE

Test material

Test material information

Constituent 1

Reference substance name:

Behenylacrylate (Acrylate 22 45%)

IUPAC Name:

Behenylacrylate (Acrylate 22 45%)

Constituent 2

Reference substance name:

2-Propenoic acid, C18-26-alkyl esters

EC Number:

285-348-3

EC Name:

2-Propenoic acid, C18-26-alkyl esters

Cas Number:

85085-17-2

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

Based on the results of ECVAM funded validation studies, it was concluded by the ECVAM Scientific Advisory Committee that the EpiDerm human epidermis model is suitable to be used for distinguishing between corrosive and non-corrosive chemicals as well as between irritant and non-irritant chemicals.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: Epi-200
- Origin: MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: Room temperature for 25 min, 37 °C for 35 min
- Temperature of post-treatment incubation (if applicable): 37 °C

REMOVAL OF TEST MATERIAL AND CONTROLS
- Volume and number of washing steps: The tissues were washed with sterile PBS to remove residual test material 1 hour after start of application. After incubation, the tissues were washed with PBS to stop the MTT-incubation.

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 0.9 mL MTT solution
- Incubation time: 55 - 65 min
- Spectrophotometer: Sunrise Absorbance Reader
- Wavelength: 570 nm

NUMBER OF REPLICATE TISSUES: 3

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be an irritant to skin if the viability is less than or equal to 50%
- The test substance is considered to be a non-irritant to skin if the viability is greater than 50%

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 50 mg

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 30 µL

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 30 µL
- Concentration (if solution): 5 % (w/v)

Duration of treatment / exposure:

1 hour

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean

Value:

96

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Any other information on results incl. tables

The test substance is able to reduce MTT directly. Subsequent testing of MTT reduction control was not performed, because no visible residues of the test substance remained on the tissues after washing.

The mean viability of the test-substance treated tissues determined after an exposure period of 1 hour with about 42 hours post-incubation was 96%.

Based on the observed results and applying the evaluation criteria, it was concluded, that Behenylacrylate (Acrylate 22 45%) does not show a skin irritation potential in the EpiDerm™ skin irritation test under the test conditions chosen.

Test substance		Tissue 1	Tissue 2	Tissue 3	mean	SD
NC	Mean OD570	1.719	1.928	1.741	1.796
	Viability [% of NC]	95.7	107.3	96.9	100	6.39
11/0546-1	Mean OD570	1.735	1.755	1.686	1.725
	Viability [% of NC]	96.6	97.7	93.9	96	1.98
PC	Mean OD570	0.121	0.127	0.128	0.125
	Viability [% of NC]	6.7	7.0	7.1	7	0.21

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

No prediction can be made for skin irritation according to GHS criteria based on the results of this in vitro study alone.
Based on the observed results and applying the evaluation criteria 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.

Executive summary:

The potential of the test substance to cause dermal irritation was assessed by a single topical application of the test substance to a reconstructed three dimensional human epidermis model (EpiDerm). Because the waxy test substance could not be applied with a pipette, a metal pin was covered with about 50 mg of the undiluted test substance.

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 test substance 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 able to reduce MTT directly. Subsequent testing of MTT reduction control was not performed, because no visible residues of the test substance remained on the tissues after washing.

The mean viability of the test substance treated tissues determined after an exposure period of 1 hour with about 42 hours post-incubation was 96 %.

Based on the observed results and applying the evaluation criteria 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.