2-Naphthalenol, 1-[2-[2-ethyl-4-[2-(2-ethylphenyl)diazenyl]phenyl]diazenyl]-, ar-heptyl derivs.

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

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)

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: MatTek Corporation Protocol for: In Vitro EpiDermTM Skin Irritation Test (EPI-200-SIT) For use with MatTek Corporation’s Reconstructed Human Epidermal Model EpiDerm (EPI-200-SIT); Version 07-Nov-2014

GLP compliance:

yes

Test material

Test material information

1

Reference substance name:

Reaction products of 2-Ethylaniline with heptyl naphthalen-2-ol

Cas Number:

1401000-07-4

Molecular formula:

Not applicable (UVCB Substance)

IUPAC Name:

Reaction products of 2-Ethylaniline with heptyl naphthalen-2-ol

Test material form:

solid

Specific details on test material used for the study:

Batch No.: 80-47-16
Storage Conditions: Room temperature, protected from light
Expiry Date: August 2017

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

This test uses the EpiDerm™ reconstructed human epidermis model (MatTek) which consists of normal human epidermal keratinocytes (NHEK) and therefore represents in vitro the target organ of the species of interest and closely mimics the biochemical and physiological properties of the upper parts of the human, i.e. the epidermis.

Vehicle:

unchanged (no vehicle)

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

1. Negative control: 30 μL DPBS
2. Positive control: 30 μL 5% SDS solution
3. Test Item: 25 mg + 25 μL DPBS

Duration of treatment / exposure:

60 min exposure

Duration of post-treatment incubation (if applicable):

42 h post-incubation period

Number of replicates:

The test was performed on a total of 3 tissues per dose group.

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Test Item 1

Value:

102.1

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Test Item 2

Value:

99.5

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Test item 3

Value:

104.9

Negative controls validity:

valid

Positive controls validity:

valid

Results 4

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Mean Value

Value:

102.2

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In this study under the given conditions the test item showed no irritant effects. The relative mean tissue viability after 60 min of exposure and 42 h post-incubation was > 50%. The test item is therefore classified as “non-irritant” in accordance with UN GHS “No Category”.

Executive summary:

The potential of the test item to induce skin irritation was analysed by using the three-dimensional human epidermis model EpiDerm™(MatTek) comprising a reconstructed epidermis with a functional stratum corneum.

In the present study RED 2735 was applied topically to the EpiDerm™ tissue for 60 min followed by a 42 h post-incubation period and immediate determination of cytotoxic effects via MTT reduction assay.

Irritant potential of the test item was predicted from the relative mean tissue viabilities obtained compared to the corresponding negative control tissues concurrently treated with DPBS.

The test item showed no irritant effects. The mean relative tissue viability (% negative control) was > 50% (102.2%) after 60 min treatment and 42 h post-incubation.

The controls confirmed the validity of the study. The mean absolute OD570 of the three negative control tissues was ≥ 0.8 and ≤ 2.8. The mean relative tissue viability (% negative control) of the positive control was ≤ 20% (3.8%). Standard deviation of viability of replicate tissues of all dose groups was ≤ 18% (0.8% - 8.0%).