1-butyl-5-[(4-chlorophenyl)azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxonicotinonitrile

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 25 JUNE 2018 to 31 AUGUST 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1-butyl-5-[(4-chlorophenyl)azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxonicotinonitrile

EC Number:

274-126-1

EC Name:

1-butyl-5-[(4-chlorophenyl)azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxonicotinonitrile

Cas Number:

69808-32-8

Molecular formula:

C17H17ClN4O2

IUPAC Name:

1-butyl-5-[(4-chlorophenyl)azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxonicotinonitrile

Test material form:

solid: particulate/powder

Details on test material:

- State of aggregation: powder
- Particle size distribution: not determined
- Mass median aerodynamic diameter (MMAD): not determined
- Geometric standard deviation (GSD): not determined
- Shape of particles: not determined
- Surface area of particles: not determined
- Crystal structure: not determined
- Coating: none
- Surface properties: not determined
- Density: 1.3526 ± 0.0010 g/cm3 at 20.0 ± 0.2°C
- Moisture content: <0.5%
- Residual solvent: not detected
- Activation: none
- Stabilisation: none
- Other:

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

foreskin from multiple donors

Source strain:

not specified

Details on animal used as source of test system:

No animals were used

Justification for test system used:

The objective of this study was to determine the potential skin corrosivity of a test item 1-butyl-5-[(4-chlorophenyl)azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxonicotinonitrile with the in vitro skin corrosion test using reconstructed human epidermis (RhE; EpiSkinTM-SM) following OECD test guideline 431. This method allows classification of the test item in non-corrosive or corrosive substances and mixtures according to the United Nations (UN) Globally Harmonized System of Classification and Labelling of Chemicals (GHS). It also allows a partial sub-categorization of corrosives.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: Reconstructed Human Epidermis (RhE; EpiSkinTM-SM).
- Tissue batch number(s): 18-EKIN-030
- Production date:
- Shipping date:
- Delivery date:
- Date of initiation of testing: 24.07.18

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 +/- 1ºC
- Temperature of post-treatment incubation (if applicable):

REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps:
- Observable damage in the tissue due to washing:
- Modifications to validated SOP:

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 0.3 mg/ml
- Incubation time: 3h +/- 15 min
- Spectrophotometer:
- Wavelength: between 540 to 600 nm
- Filter: no reference filter was used
- Filter bandwidth:
- Linear OD range of spectrophotometer:

FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability:
- Barrier function:
- Morphology:
- Contamination:
- Reproducibility:

NUMBER OF REPLICATE TISSUES:

CONTROL TISSUES USED IN CASE OF MTT DIRECT INTERFERENCE
- Fresh tissues / killed tissues
- Procedure used to prepare the killed tissues (if applicable):
- N. of replicates :
- Method of calculation used:

NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION:

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be corrosive to skin if [complete, e.g. the viability after 3 minutes exposure is less than 50%, or if the viability after 3 minutes exposure is greater than or equal to 50 % and the viability after 1 hour exposure is less than 15%.]
- The test substance is considered to be non-corrosive to skin if [complete, e.g. the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15%.]
- Justification for the selection of the cut-off point(s) if different than recommended in TG 431 and 439:

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 20g
- Concentration (if solution):

VEHICLE
- Amount(s) applied (volume or weight with unit): 100%
- Concentration (if solution):
- Lot/batch no. (if required):
- Purity: none

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 50 µL of negative control (0.9% NaCl)
- Concentration (if solution): 0.9% NaCl

POSITIVE CONTROL
- Amount(s) applied (volume or weight):50 µL of positive control (glacial acetic acid)
- Concentration (if solution): 100%

Duration of treatment / exposure:

3 min, 1h (±5 min) and 4h (±10 min) at room temperature

Duration of post-treatment incubation (if applicable):

incubated for 3h (± 15 min) under culture conditions

Number of replicates:

A single testing run was sufficient becuuse was unequivocal.

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Run 1 (duration exposure time 3 minutes), Run 2 (duration exposure time 1 hour) and run 3 (duration exposure time 4 hours)

Value:

>= 35

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Remarks:

Taking into account the results obtained in the current study, it is concluded that, under the assayed experimental conditions and according to the OECD guideline for the Testing of Chemicals Nº. 431, the test item 1-butyl-5-[(4-chlorophenyl)azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxonicotinonitrile can be categorised as Non-Corrosive according to the United Nations Globally Harmonized System of Classification and Labelling of Chemicals.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Taking into account the results obtained in the current study, it is concluded that, under the assayed experimental conditions and according to the OECD guideline for the Testing of Chemicals Nº. 431, the test item 1-butyl-5-[(4-chlorophenyl)azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxonicotinonitrile can be categorised as Non-Corrosive according to the United Nations Globally Harmonized System of Classification and Labelling of Chemicals.