Registration Dossier

Administrative data

Description of key information

Skin irritation

Skin irritation effects were estimated by four different models i.e, Battery, Leadscope, SciQSAR and CASE Ultra used within Danish QSAR database for the given test chemical. Based on estimation, severe skin irritation effects were known when test chemical was exposed to rabbit skin. Hence, it can be considered to be irritating to skin.

 

Eye irritation

The ocular irritation potential of test article was determined according to the OECD 492 test guideline followed for this study. The mean of OD for test chemical was determined to be 1.888. Tissue 2 (well C1 and D1) of the negative control did not look 100% okay after the treatment, which may be due to some kind of damage of the tissue. This gives us a SD of D>20, however, the negative control can still be used since the SD error bar is above the cut-off-limit of the assay (i.e. 60%). The mean % tissue viability of test chemical was determined to be 98.5%. Thus, test chemical was considered to be not irritating to the human eyes.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records
Reference
Endpoint:
skin irritation: in vivo
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
accepted calculation method
Justification for type of information:
data is from prediction database.
Qualifier:
according to
Guideline:
other: estimated data
Principles of method if other than guideline:
To estimate the skin irritation potential of the given test chemical.
GLP compliance:
not specified
Specific details on test material used for the study:
- Name of test material (IUPAC name): Naphthalene-2-sulphonyl chloride
- Common name: 2-Naphthalenesulfonyl chloride
- Molecular formula: C10H7ClO2S
- Molecular weight: 226.682 g/mol
- Smiles notation: c12c(ccc(c1)S(=O)(=O)Cl)cccc2
- InChl: 1S/C10H7ClO2S/c11-14(12,13)10-6-5-8-3-1-2-4-9(8)7-10/h1-7H
- Substance type: Organic
-Physical property- Light Yellow to Beige powder
Species:
rabbit
Strain:
not specified
Details on test animals and environmental conditions:
not specified
Type of coverage:
not specified
Preparation of test site:
not specified
Vehicle:
not specified
Controls:
not specified
Amount / concentration applied:
not specified
Duration of treatment / exposure:
not specified
Observation period:
not specified
Number of animals:
not specified
Details on study design:
not specified
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: no data available
Reversibility:
not specified
Remarks on result:
positive indication of irritation
Irritant / corrosive response data:
Signs of irritation estimated.

Table showing skin irritation estimation by three different models i.e, Leadscope, battery and SciQSAR &CASE Ultra,the average skin irritation results was given by the fourth model i.e, Battery model.

DK

EXP

Battery

SciQSAR

CASE Ultra

Leadscope

Skin irritation in rabbit

 

POS

POS

POS

INC OUT

Domain

 

IN

IN

IN

IN

                                                                      

Where,

IN = inside applicability domain, EXP = Experimental data

Interpretation of results:
Category 2 (irritant) based on GHS criteria
Conclusions:
Severe skin irritation effects of the given test chemical were estimated in rabbit skin by four different models i.e, Battery, Leadscope, SciQSAR and CASE Ultra used within Danish QSAR database.
Executive summary:

Skin irritation effects were estimated by four different models i.e, Battery, Leadscope, SciQSAR and CASE Ultra used within Danish QSAR database for the given test chemical. Based on estimation, severe skin irritation effects were known when test chemical was exposed to rabbit skin. Hence, it can be considered to be irritating to skin.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Eye irritation

Link to relevant study records
Reference
Endpoint:
eye irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
Data is from experimental study report.
Qualifier:
according to
Guideline:
OECD Guideline 492 (Reconstructed Human Cornea-like Epithelium (RhCE) Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage)
Principles of method if other than guideline:
The purpose of this study was to assess potential for the test article to be ocular irritants. The ocular irritation potential of a test article may be predicted by measurement of its cytotoxic effect, as reflected in the (MTT) assay, in the MatTek EpiOcular™ model
GLP compliance:
no
Specific details on test material used for the study:

RADIOLABELLING INFORMATION (Not 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: Room temperature / Fridge storage
- Stability under test conditions: No data available
- Solubility and stability of the test substance in the solvent/vehicle: No data available
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: No data available

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test article tested as provided neat (undiluted).
- Preliminary purification step (if any): No data available
- Final dilution of a dissolved solid, stock liquid or gel: No data available
- Final preparation of a solid: No data available

FORM AS APPLIED IN THE TEST:solid
Species:
human
Strain:
other: Not applicable
Details on test animals or tissues and environmental conditions:
- Description of the cell system used:
The normal human-derived keratinocytes were cultured at the air-liquid interface in a chemically defined medium on a permeable polycarbonate insert (surface 0.5 cm2). They were cultured in chemically defined serum free medium to form a multi-layered epithelium similar to that found in native corneal mucosa. Each lot of tissues was Quality Assured by MatTek according to specific QC standards including: histology, tissue viability (MTT mean optical density), reproducibility (SD) and tissue thickness.

- Test System Identification
All of the EpiOcular™ 3-dimensional human tissues used in this study were identified by the date of arrival and the lot number. Certificate of Analysis for the tissues is included in this report. Tissue plates were appropriately labeled with study information. Bias was not a factor in this test system.
- Justification of the test method and considerations regarding applicability
EpiOcularTM Eye Irritation (OCL) by MatTek In Vitro Life Science Laboratories, Bratislava, Slovakien

The test articles and controls were evaluated for potential ocular irritancy using the EpiOcular™ 3 dimensional human tissue model purchased from MatTek,In Vitro Life Science Lab. (Bratislava, Slovakia).The EpiOcular tissue construct is a nonkeratinized epithelium prepared from normal human keratinocytes (MatTek). It models the cornea epithelium with progressively stratified, but not cornified cells. These cells are not transformed or transfected with genes to induce an extended life span in culture. The “tissue” is prepared in inserts with a porous membrane through which the nutrients pass to the cells. A cell suspension is seeded into the insert in specialized medium. After an initial period of submerged culture, the medium is removed from the top of the tissue so that the epithelial surface is in direct contact with the air. This allows the test material to be directly applied to the epithelial surface in a fashion similar to how the corneal epithelium would be exposed in vivo. Each lot of tissues was Quality Assured by MatTek, Inc. according to specific QC standards including: histology (cell layers), tissue viability (MTT mean optical density) and reproducibility (SD).
Vehicle:
unchanged (no vehicle)
Controls:
yes, concurrent positive control
yes, concurrent negative control
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 50 mg of solid test chemical
- Concentration (if solution): neat (undiluted)

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

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 50 μL
- Concentration (if solution): neat

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 50 μL
- Concentration (if solution): neat
Duration of treatment / exposure:
Tissues were exposed for approximately 6 hrs ± 15 min for solid test articles, and controls, at approximately 37°C, 5% CO2 in a humidified incubator.
Observation period (in vivo):
Not applicable
Duration of post- treatment incubation (in vitro):
Following the washing and post soak, the tissues were rinsed and incubated at approximately 37°C, 5% CO2 in a humidified incubator for a post-exposure recovery time of 18 hours for solid test chemicals and controls
Number of animals or in vitro replicates:
2 tissues were used for test compound and control.
Details on study design:
- Details of the test procedure used
The tissues were exposed to the test article neat (undiluted). EpiOcular™ tissues were purchased from MatTek. Quality control of the tissues was performed by MatTek and the Certificate of Analysis (CoA)
for the tissues is provided and is kept in the study binder. Tissues were exposed for approximately 6 hrs ± 15 min for solid test articles and controls at approximately 37°C, 5% CO2 in a humidified incubator.
After the exposure, the test article was rinsed off the tissues and the tissues were soaked in media for ~25 minutes for solid test articles and controls.Following the washing and post soak, the tissues were rinsed and incubated at approximately 37°C, 5% CO2 in a humidified incubator for a post-exposure recovery time of 18 hours for solid test chemicals and controls.Tissue viability was assessed by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

- MTT Auto reduction and colouring assessment
MTT Pre-test
The test article was assessed for the potential to interfere with the assay. Approximately 50 µL of liquid test article was added to 1 mL of MTT media (~1 mg/mL) and incubated in a humidified incubator at approximately 37°C and approximately 5% CO2 for 3 hours. 50 µL of ultrapure water was used as a negative control.
- Test Article Color Test
Approximately 50 µL of liquid test article was added to 1.0 mL of ultrapure water and 2.0 mL isopropanol and incubated in a humidified incubator at approximately 37°C and approximately 5% CO2 for 2 hours, 04 minutes and 35 seconds. Samples were then added to the wells of a clear 96-well plate and the plate was read on a Thermo Scientific Multiskan FC Microplate Photometer to 570 nm. Test articles that tested positive for excessive coloration (OD >0.08) were assessed on living-tissue controls that were incubated in both culture media and MTT media as well (n=3 for both conditions).

- MTT Assay:
Inserts are removed from the 24-well plate after 3 hrs of incubation and the bottom of the insert is blotted on absorbent material, and then transferred to a pre-labeled 6-well plate containing 1 ml isopropanol in each well so that no isopropanol is flowing into the insert. At the end of the non-submerged extraction inserts and tissues are discarded without piercing and 1 ml of isopropanol is added into each well. The extract solution is mixed and the optical density of the extracted formazan (200 μL/well of a 96-well plate) was determined using Thermo Scientific Multiskan FC Microplate Photometer at 570 nm. Relative cell viability was calculated for each tissue as % of the mean negative control tissues.

- Evaluation of Test Article in the cell Models
1. Cell System:
Upon receipt, the MatTek EpiOcular™ tissue cultures were placed in 1.0 mL of fresh Maintenance medium (in a 6-well plate) for 60 minutes. After the 60 minutes incubation, the Maintenance medium was exchanged with fresh medium and the tissues were incubated overnight (16-24 hrs) at approximately 37°C, approximately 5% CO2 in a humidified incubator.
2. Control and Test Article Exposures:
20 µL of calcium and magnesium free DPBS was added to each tissue and the tissues placed back into the incubator for 30 minutes. The controls and the test article will be applied topically to tissues by pipette.2 tissues will be used per test compound and control.
a)Controls: 50 µL of negative control sterile ultrapure water and positive control methyl acetate were added to the tissues. The tissues were placed into the ~37°C humidified incubator with 5% CO2 for the approximately 30 minute exposure time.
b)Test Article: When a solid was tested, 50 mg of the solid were added to the tissues. The tissues were placed into the ~37°C humidified incubator with 5% CO2 for the approximately 6 hrs ± 15 min.
3. Post exposure treatment:
After the exposure, the tissues were rinsed 20 times with sterile of DPBS to remove test material. The apical surface was gently blotted with a cotton swab and cultures were immediately transferred to a 12-well plate containing 5 mL of media per well. Tissues exposed to liquid test articles (and the respective control) were incubated, submerged in the media for ~12 minutes at room temperature.For liquid test articles, tissues, Tissuses were then transferred to 6-well plates containing 1.0 mL fresh Maintenance medium per well and incubated for a post-exposure recovery period for 2 hours at approximately 37 degC, 5% CO2 in a humidified incubator.
- Doses of test chemical and control substances used
Test Article:
When a solid was tested, 6 hours of the solid were added to the tissues. The tissues were placed into the ~37°C humidified incubator with 5% CO2 for the approximately 6 hrs ± 15 min.
Controls: 50 µL of negative control sterile ultrapure water, positive control methyl acetate were added to the tissues. The tissues were placed into the ~37°C humidified incubator with 5% CO2 for the approximately 30 minute exposure time.

- Duration and temperature of exposure, post-exposure immersion and post-exposure incubation periods:
Tissues were exposed for approximately 6 hours for solid test articles and controls, at approximately37°C, 5% CO2 in a humidified incubator.
Following the post soak, the tissues were rinsed and incubated at approximately 37°C, 5% CO2 in a humidified incubator for a post-exposure recovery time totaling 18 hours for solid test articles and controls.

- Justification for the use of a different negative control than ultrapure H2O (Not applicable)
- Justification for the use of a different positive control than neat methyl acetate (Not applicable)
- Number of tissue replicates used per test chemical and controls: 2 tissues were used for test compound and control.
- Description of the method used to quantify MTT formazan
The blue formazan salt was extracted by placing the tissue insterts in 1 mL isopropanol in a 6-well plate. The extraction for solid exposed tissues was 3 hrs incubation. After an addition of 1 ml isopropanol and mixing, the optical density of the extracted formazan (200μL/well of a 96-well plate) was determined using a Thermo Scientific Multiskan FC Microplate Photometer at 570 nm.

- Description of evaluation criteria used including the justification for the selection of the cut-off point for
the prediction model
Calculations and Statistical Methods
MTT Assay
Blanks:
· The OD mean from all replicates for each plate (ODblank).
Negative Controls (NC):
· The blank corrected value was calculated: ODNC= ODNCraw– ODblank.
· The OD mean per NC tissue was calculated.
· The mean OD for all tissues corresponds to 100% viability.
· The mean, standard deviation (SD), standard error of the mean (SEM) and the percent coefficient of variation (% CV) was calculated.
ODblank= optical density of blank samples (isopropanol alone).
ODNCraw= optical density negative control samples.
ODNC= optical density of negative control samples after background subtraction.
Positive Control (PC):
· Calculate the blank corrected value: ODPC= ODPCraw– ODblank.
· The OD mean per PC tissue was calculated.
· The viability per tissue was calculated: %PC = [ODPC/ mean ODNC] x 100.
· The mean viability for all tissues was calculated: Mean PC = Σ %PC / number of tissues.
· The standard deviation (SD), standard error of the meanthe mean (SEM) and the percent coefficient of variation (% CV) was calculated.
ODPCraw= optical density positive control samples.
ODPC= optical density of positive control samples after background subtraction.
Tested Articles:
· Calculate the blank corrected value ODTT= ODTTraw– ODblank.
· The OD mean per tissue is calculated.
· The viability per tissue is calculated: %TT = [ODTT/ mean ODNC] x 100.
· The mean viability for all tissues is calculated: Mean TT = Σ %TT / number of tissues.
· The standard deviation (SD) and the percent coefficient of variation (% CV)for the controls and the test articles will be calculated.
ODTTraw= optical density test article samples.
ODPC= optical density of test article samples after background subtraction.
Data Correction Procedure for MTT Interfering Compounds
True viability = Viability of treated tissue – Interference from test article = ODtvt – ODkt where ODkt =
(mean ODtkt – mean ODukt).
ODtvt = optical density of treated viable tissue
ODkt = optical density of killed tissues
ODtkt = optical density of treated killed tissue
ODukt = optical density of untreated killed tissue (NC treated tissue)
Data Correction Procedure for Colored Compounds
True viability = Viability of treated tissue incubated in MTT media – Viability of treated tissue incubated in
media without MTT = ODtvt – ODvt.
ODtvt = optical density of treated viable tissue incubated in MTT media
ODvt = optical density of viable tissues incubated in media alone.
Proposed Statistical methods
The mean, standard deviation (SD) and the percent coefficient of variation (% CV) for the controls and the test article will be calculated.
- Evaluation of data
The results of the assay was evaluated and compared to negative control.
Table: Irritancy Prediction
In VitroResults In VivoPrediction
Mean tissue viability ≤60% Irritant (I) – Category 1 or 2
Mean tissue viability >60% Non-irritant (NI) – No Category
- Assay quality controls
- Negative Controls (NC)
The assay is meeting the acceptance criterion if the mean viability of the NC in terms of Optical Density(OD570) of the NC tissues (treated with sterile ultrapure water) in the MTT assay are >0.8 to <2.5. This is an indicator of tissue viability following shipping and conditions under use.
- Positive Controls (PC)
Methyl acetate was used as a PC and tested concurrently with the test article. The assay is meeting the acceptance criteria if the viability of the PC is <50% of the negative control.
- Standard Deviation (SD)
Each test of ocular irritancy potential is predicted from the mean viability determined on 2 single tissues. The assay meets the acceptance criteria if SD calculated from individual percent tissue viabilities of the
replicates is <18% for three replicate tissues.
Irritation parameter:
other: mean % tissue viability
Run / experiment:
Run 1
Value:
98.5
Vehicle controls validity:
not specified
Negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: mean of OD :1.888; Non-Irritant
Other effects / acceptance of results:
The MTT data show the assay quality controls were met.

Tissue 2 (well C1 and D1) of the negative control did not look 100% okay after the treatment, which may be due to some kind of damage of the tissue. This gives us a SD of D>20, however, the negative control can still be used since the SD error bar is above the cut-off-limit of the assay (i.e. 60%).

Interpretation of results:
other: not irritating
Conclusions:
The ocular irritation potential of test article was determined according to the OECD 492 test guideline followed for this study. The mean of OD for test chemical was determined to be 1.888. Tissue 2 (well C1 and D1) of the negative control did not look 100% okay after the treatment, which may be due to some kind of damage of the tissue. This gives us a SD of D>20, however, the negative control can still be used since the SD error bar is above the cut-off-limit of the assay (i.e. 60%). The mean % tissue viability of test chemical was determined to be 98.5%. Thus, test chemical Naphthalene-2-sulphonyl chloride was considered to be not irritating to the human eyes.
Executive summary:

The ocular irritation potential of test article was determined according to the OECD 492 test guideline for this study. The MatTek EpiOcular™ model was used to assess the potential ocular irritation of the test articles by determining the viability of the tissues following exposure to the test article via MTT. Tissues were exposed to liquid test articles and controls for ~30 minutes, followed by a ~12 minute post-soak and approximately 2 hour recovery after the post-soak. The viability of each tissue was determined by MTT assay. The MTT data show the assay quality controls were met, passing the acceptance criteria. The mean of OD for test chemical was determined to be 1.888.Tissue 2 (well C1 and D1) of the negative control did not look 100% okay after the treatment, which may be due to some kind of damage of the tissue. This gives us a SD of D>20, however, the negative control can still be used since the SD error bar is above the cut-off-limit of the assay (i.e. 60%). The mean % tissue viability of test chemical Naphthalene-2-sulphonyl chloride was determined to be 98.5%. Hence, under the experimental test conditions it was concluded that test chemical was considered to be non-irritating to the human eyes.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Skin Irritation:

In different studies, the given test chemical has been investigated for the dermal irritation potential to a greater or lesser extent. The studies are based on in-vivo and in-vitro experiments conducted in rabbits and human skin respectively, which have been summarized as below -

 

Skin irritation effects were estimated by four different models i.e, Battery, Leadscope, SciQSAR and CASE Ultra used within Danish QSAR database for the given test chemical. Based on estimation, severe skin irritation effects were known when test chemical was exposed to rabbit skin. Hence, it can be considered to be irritating to skin.

 

The above study is supported with another skin irritation study performed in New Zealand White rabbits to assess the irritation potential. 500 mg of test material with about 0.1 mL of sterile distilled water was applied on abraded and intact sites on the shaved backs (2.5 x 2.5 cm) of rabbits. Left side of the back was treated as control. It was held in place for 4 hours with three fold gauze patches, which was applied in place with elasticity bandage then was fixed with non-irritating tape (3M paper-tape). After 4 hours, three fold gauze patches were removed and the exposed areas washed using warm water without altering the existing response or the integrity of the epidermis. The skin of animals was examined in accordance with an OECD scoring method for signs of erythema and oedema and the responses scored at 1, 24, 48 and 72 hours after the patches removal. Test chemical was applied on the rabbit’s back in concentration 500 mg. Erythema, scab and edema were observed at the abraded and intact skins on the backs of three rabbits. Hence, it is considered to be moderately irritating.

 

Both the above results are supported with the 16-Day cumulative irritation test was carried out on rabbits to assess the irritation potential of the test chemical. Six New Zealand albino rabbits were used for each test. The animals' backs were clipped on a Saturday, and on two subsequent Saturdays. Each test material was applied 14 times, on Mondays to Fridays except for the last Friday. 0·05 ml of 10% and 1% test chemical in alcohol was applied to one of four sites on the back of each clipped rabbit two anterior and two posterior, two being on each side of the dorsal midline. Each test site was scored visually, together with one centrally located control site, and some were measured for skinfold thickness to the nearest 0.1 mm at 24hr and every subsequent day except Sundays (16 readings). The scores used were 0 for no erythema, I for barely perceptible erythema, 2 for well-defined erythema, 3 for moderate to severe erythema and 4 for beet-red erythema to slight eschar and/or disruption of epidermal intactness. Scaliness was arbitrarily assigned a score of 1. The average cumulative irritation score was then calculated (maximum score = 64); applications of 10% and 1% produced scores of 3.6 and 0.3, respectively. Hence, the test chemical was considered to be irritating to skin when subjected to repeated exposure.

 

All the above in-vivo studies are contradicted with the in-vitro study conducted to assess the dermal irritation potential of test chemical according to the OECD 439 test guideline. The MatTek EpiDerm™ model was used to assess the potential dermal irritation of the test article by determining the viability of the tissues following exposure to the test article via MTT. Tissues were exposed to the test article and controls for ~one hour, followed by a 42 hour post-exposure recovery period. The viability of each tissue was determined by MTT assay. The MTT data show the assay quality controls were met and passed the acceptance of criteria. The mean of OD for test chemical was determined to be 2.040. The standard deviation of viabilities for test chemical was calculated to be 5.95. The Mean % tissue viability compared to negative control (n=3) of the test chemical was determined to be 110.2%. Hence, under the current experimental test conditions it was concluded that test chemical was considered to be non-irritating to human skin.

 

Even though the results of in-vitro study on human skin indicate a possibility of the test chemical being non-irritating to skin, but the remaining studies suggest otherwise. Also, the estimation on skin irritation effects due to the test chemical indicates a positive effect. Taking into consideration, all these parameters, the test chemical can be considered to be irritating to skin. Comparing the above annotations with the criteria of CLP Regulation, the given test chemical can be classified as ''Irritating to skin in Category 2”.

 

 

Eye irritation

The ocular irritation potential of test article was determined according to the OECD 492 test guideline for this study. The MatTek EpiOcular™ model was used to assess the potential ocular irritation of the test articles by determining the viability of the tissues following exposure to the test article via MTT. Tissues were exposed to liquid test articles and controls for ~30 minutes, followed by a ~12 minute post-soak and approximately 2 hour recovery after the post-soak. The viability of each tissue was determined by MTT assay. The MTT data show the assay quality controls were met, passing the acceptance criteria. The mean of OD for test chemical was determined to be 1.888.Tissue 2 (well C1 and D1) of the negative control did not look 100% okay after the treatment, which may be due to some kind of damage of the tissue. This gives us a SD of D>20, however, the negative control can still be used since the SD error bar is above the cut-off-limit of the assay (i.e. 60%). The mean % tissue viability of test chemical Naphthalene-2-sulphonyl chloride was determined to be 98.5%. Hence, under the experimental test conditions it was concluded that test chemical was considered to be non-irritating to the human eyes.

 

The above in-vitro result is supported with the in-vivo data of eye irritation study performed to determine the eye irritation potential of the test chemical in rabbits. About 50 mg (the test chemical was dry and ground, made into paste with water) was instilled into the eyes of 2 New Zealand White rabbits. The rabbits were observed for signs of irritation till 7 days. Slight reddening was seen in 1 rabbits after 1 hour after application which got completely cleared up by 3 days. Since the effects were fully reversible, the test chemical was considered to be not irritating to rabbit eyes.

 

The above study is supported by the results of an eye irritation study conducted to evaluate the irritant nature of the test chemical in rabbits. In this study, 50 mg of test chemical was instilled into the conjunctival sac of 2 animals and animals were observed for 7 days. No eye irritation was observed after 7 days. Hence the test chemical was considered as non-irritant to rabbit eyes.

 

Based on the available data from in-vivo and in-vitro results, both the results are in mutual agreement with each other indicating a strong possibility that the test chemical is indeed not irritating to eyes. Comparing the above annotations with the criteria of CLP Regulation, the test chemical cannot be classified for “Eye irritation”.

Justification for classification or non-classification

Even though the results of in-vitro study on human skin indicate a possibility of the test chemical being non-irritating to skin, but the remaining studies suggest otherwise. Also, the estimation on skin irritation effects due to the test chemical indicates a positive effect. Taking into consideration, all these parameters, the test chemical can be considered to be irritating to skin. Comparing the above annotations with the criteria of CLP Regulation, the given test chemical can be classified as ''Irritating to skin in Category 2”.

 

Based on the available data from in-vivo and in-vitro results, both the results are in mutual agreement with each other indicating a strong possibility that the test chemical is indeed not irritating to eyes. Comparing the above annotations with the criteria of CLP Regulation, the test chemical cannot be classified for “Eye irritation”.