2-hydroxy-N-1H-1,2,4-triazol-3-ylbenzamide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 August 2017 - 21 August 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

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)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-hydroxy-N-1H-1,2,4-triazol-3-ylbenzamide

EC Number:

253-021-4

EC Name:

2-hydroxy-N-1H-1,2,4-triazol-3-ylbenzamide

Cas Number:

36411-52-6

Molecular formula:

C9H8N4O2

IUPAC Name:

2-hydroxy-N-1H-1,2,4-triazol-3-ylbenzamide

Test material form:

solid: particulate/powder

Details on test material:

Batch:102Z5
Purity: 99.9%
white powder

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

foreskin from a single donor

Source strain:

not specified

Details on animal used as source of test system:

Not specified

Justification for test system used:

The EPISKINTM model is a three-dimensional reconstructed human epidermis model consisting of adult human-derived epidermal keratinocytes seeded on a dermal substitute consisting of a collagen type I matrix coated with type IV collagen. A highly differentiated and stratified epidermis model is obtained after a 13-Day culture period comprising of the main basal, supra basal, spinous and granular layers and a functional stratum corneum.
Following a full validation study the EpiSkinTM reconstructed human epidermis model showed evidence of being a reliable and relevant stand-alone test for predicting rabbit skin irritation when the endpoint is measured by MTT reduction and for being used as a replacement for the Draize Skin Irritation Test for the purpose of distinguishing between Irritating and Non-Irritating test items.

Vehicle:

unchanged (no vehicle)

Details on test system:

SKIN DISC PREPARATION
- Procedure used: 2 mL of maintenance medium, warmed to approximately 37 °C, was pipetted into the first column of 3 wells of a pre-labeled 12-well plate. Each epidermis unit was transferred into the maintenance medium filled wells (3 units per plate). A different 12-well plate was used for the test item and each control item.
TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 °C
REMOVAL OF TEST MATERIAL AND CONTROLS
At the end of the exposure period, each tissue was removed from the well using forceps and rinsed using a wash bottle containing DPBS with Ca++ and Mg++. Rinsing was achieved by filling and emptying each tissue insert for approximately 40 seconds using a constant soft stream of DPBS to gently remove any residual test item. The rinsed tissues were transferred to the second column of 3 wells containing 2 mL of maintenance medium in each well. The rinsed tissues were incubated at 37 °C, 5% CO2 in air for 42 hours.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10mg

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): DPBS used as supplied

POSITIVE CONTROL
- Concentration (if solution): 5% w/v aqueous solution

Duration of treatment / exposure:

15 minutes

Duration of post-treatment incubation (if applicable):

37 °C, 5% CO2 in air for 42 hours

Number of replicates:

Three

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Value:

ca. 102.5

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

- OTHER EFFECTS:
- Visible damage on test system: no
- Direct-MTT reduction:no
- Colour interference with MTT: no

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Acceptance criteria met for variability between replicate measurements: yes

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was classified as non-irritant. The following classification criteria apply:
EU CLP Not classified for Irritation.
UN GHS Not classified for Irritation (category 3 can not be determined).