N-(2-hydroxyethyl)dodecanamide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 August 2017 - 01 February 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study was conducted in accordance with international guidelines and in accordance with GLP. All guideline validity criteria were met.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

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)

Version / remarks:

July 28 2015

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

23 July 2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

N-(2-hydroxyethyl)dodecanamide

EC Number:

205-560-1

EC Name:

N-(2-hydroxyethyl)dodecanamide

Cas Number:

142-78-9

Molecular formula:

C14H29NO2

IUPAC Name:

N-(2-hydroxyethyl)dodecanamide

Test material form:

solid

Details on test material:

Storage: Room temperature, in the dark

Specific details on test material used for the study:

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity: n/a
- Specific activity: n/a
- Locations of the label: n/a
- Expiration date of radiochemical substance: n/a

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature
- Stability under test conditions: Assumed stable
- Solubility and stability of the test substance in the solvent/vehicle: Not applicable - test item applied undiluted.
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: No

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: None, applied as supplied.
- Preliminary purification step (if any): n/a
- Final dilution of a dissolved solid, stock liquid or gel: n/a
- Final preparation of a solid: n/a

FORM AS APPLIED IN THE TEST (if different from that of starting material): n/a

OTHER SPECIFICS: n/a

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

other: epidermal keratinocytes

Cell source:

other: MatTek Corporation (82105 Bratislava, Slovakia)

Source strain:

other:

Details on animal used as source of test system:

n/a

Justification for test system used:

n/a

Vehicle:

unchanged (no vehicle)

Details on test system:

n/a

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): approximately 25 mg (~ 39 mg/cm2 according to guideline) of the test item were applied to the tissues, wetted with 25 μL DPBS prior to application, and spread to match the surface of the tissue for a complete treatment time of 60 minutes.
- Concentration (if solution): See above.

VEHICLE
- Amount(s) applied (volume or weight with unit): See above.
- Concentration (if solution): See above.
- Lot/batch no. (if required): Not reported.
- Purity: Not reported.

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 30 µL
- Concentration (if solution): n/a

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

Duration of treatment / exposure:

60 minutes.

Duration of post-treatment incubation (if applicable):

42 hours and 20 minutes

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Value:

ca. 101.9

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Any other information on results incl. tables

Table 2. Results after treatment with N-(2-hydroxyethyl) dodecanamide  and the controls.

Dose Group	Tissue No.	Absorbance 570 nm Well 1	Absorbance 570 nm Well 2	Absorbance 570 nm Well 3	Mean Absorbance of 3 Wells	Mean Absorbance of three wells blank corrected	Mean Absorbance of 3 tissues after blank correction	Rel. Absorbance [%] Tissue 1, 2 + 3	Relative Standard Deviation [%]	Mean Rel. Absorbance [%]
Blank		0.038	0.039	0.037	0.038	0.000
Negative Control	1	1.240	1.333	1.344	1.306	1.268	1.277	99.3	3.3	100.0
	2	1.357	1.369	1.359	1.361	1.323		103.6
	3	1.278	1.273	1.283	1.278	1.240		97.1
Positive Control	1	0.109	0.109	0.100	0.106	0.068	0.064	5.3	0.3	5.0
	2	0.110	0.100	0.098	0.103	0.065		5.1
	3	0.100	0.099	0.096	0.098	0.060		4.7
Test Item	1	1.212	1.300	1.315	1.276	1.238	1.301	96.9	4.9	101.9
	2	1.398	1.395	1.406	1.400	1.362		106.6
	3	1.326	1.355	1.347	1.343	1.305		102.2

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this study the test substance is not considered to be irritant to the skin and does not meet the criteria for classification in accordance with UN GHS and EU CLP regulation.

Executive summary:

OECD 439 (2017) -The skin irritation potential of N-(2-hydroxyethyl) dodecanamide  was assessed using an EpiDerm Reconstructed Human Epidermis (RHE) Model Kit in accordance with OECD guidance 439 and GLP.

Triplicate tissues were exposed to the test item for 60 minutes. At the end of the exposure period the test item was rinsed and the tissues incubated for a further 42 h in the presence of maintenance solution which would be used for possible inflammatory mediator determination. Each tissue was then loaded with MTT. After incubation and extraction, the solutions were aliquoted for absorbance measurements. Absorbency at 570 nm of each well was measured using a spectrophotometer.

Mean viability of tissues exposed to the test substance after 60 minutes were 101.9 %. It was considered unnecessary to perform IL-1a analysis as the results of the MTT test were unequivocal. The quality criteria required for acceptance of the results was met.

Under the conditions of this study the test substance,N-(2-hydroxyethyl) dodecanamide  is not irritant to skin according to UN GHS and EU CLP regulation.