Registration Dossier

Diss Factsheets

Administrative data

Description of key information

OECD439: Not irritating to the skin

OECD492: Not irritating to the eyes

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records
Reference
Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
02 Aug 2016 to 28 Jun 2017
Reliability:
1 (reliable without restriction)
Qualifier:
according to guideline
Guideline:
OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)
Version / remarks:
28 July 2015
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)
Version / remarks:
6 July 2012
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Remarks:
BASF SE, Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany
Specific details on test material used for the study:
- Name as cited in study report: Orasol Red 335
-Test-substance No.: 16/0125-1
- Batch identification: 002-141706
- Content: 96 g/100 g (100 g/100 g minus water content)
- Physical state / colour: Solid / red
- Storage conditions: Room temperature
Test system:
human skin model
Remarks:
Three dimensional human epidermis model: EpiDerm model
Source species:
human
Cell type:
non-transformed keratinocytes
Cell source:
other: cultured
Justification for test system used:
The present test is based on the experience that corrosive and irritant chemicals produce cytotoxicity in human reconstructed epidermis after a short term topical exposure.
Vehicle:
unchanged (no vehicle)
Details on test system:
MATERIALS AND TECHNICAL EQUIPMENT
- Laminar flow bench: HERAsafe KS 18 (Thermo ELECTRON CORPORATION)
- CO2 incubator: Heraeus BBD 6220
- Incubation conditions: 37°C ± 1°C, 5% ± 1% CO2, 90% ± 5% humidity
- Spectrophotometer: SunriseTM Absorbance Reader for the determination of the optical density of coloured extracts. Measurement using a filter wavelength 570 nm without reference filter
- EpiDermTM 200 kit: MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia; containing: 24 EPI-200 tissues (reconstructed epidermis): surface 0.6 cm² cultured in Millicells® ø 1 cm
- Tissue for MTT reduction control: EPI-200 tissue that is killed by freezing at -20°C
- Assay medium: EPI-100-NMM assay medium
- MTT diluent: Dulbecco's modified eagle's medium (DMEM) based medium used for diluting MTT (MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia / Sigma, Germany)
- Wash buffer: Dulbecco's phosphate buffered saline (PBS), w/o Ca2+, Mg2+ (MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia and Biochrom, Germany)
- Detection agent: 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) (MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia / Sigma, Germany), 1.0 mg / mL MTT diluent
- Extracting agent: Isopropanol p.a.

TEST SYSTEM
The EpiDermTM model consists of normal, human-derived epidermal keratinocytes which have been cultured to form a multi layered, highly differentiated model of the human epidermis. It consists of organized basal, spinous and granular layers, and a multi-layered stratum corneum containing intercellular lamellar lipid layers arranged in patterns analogous to those found in vivo. The EpiDermTM tissues (surface 0.6 cm²) are cultured on specially prepared cell culture inserts (MILLICELLs®, 10 mm ø) and commercially available as kits (EpiDermTM 200), containing 24 tissues on shipping agarose.
- Tissue model: EPI-200
- Tissue Lot Number: 23348
- Origin: MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia

DIRECT MTT REDUCTION
- The direct reduction of MTT by a test substance interferes with the colour density produced by metabolic capacity of the tissue and would falsify the test results.
- To assess the ability of the test material to directly reduce MTT a pretest (experimental conduct in accordance with GLP but without a GLP status) was performed as described below.
- The test substance was added to 0.9 mL of the MTT solution. The mixture was incubated in the dark at about 37 °C for 3 hours. A negative control (de-ionized water) was tested concurrently. If the colour of the MTT solution or, in case of water-insoluble test substances the border to the water-phase, turned blue / purple, the test substance was presumed to directly reduce MTT.
- In case that direct MTT reduction occurred, three freeze-killed control tissue (KC) were treated with the test article and the negative control.
- Due to the ability of the test substance to reduce MTT directly, KC tissues were applied in parallel.

COLOUR CONTROL
- The colour of a test substance may interfere with the colour density produced by metabolic capacity of the tissue and would falsify the test results when residues of the test substance remain on the tissues after washing and are extracted by the isopropanol.
- Due to the colour of the test substance a pretest (experimental conduct in accordance with GLP but without a GLP status) was performed as follows: the test substance was applied to a KC tissue, incubated for 1 hour and removed by washing in the same way as in the main experiment. Thereafter extraction in isopropanol was performed and the OD570 of the extract was determined spectrophotometrically.
- Based on the result of the pretest it was judged that application of colour control tissues is not necessary.

BASIC PROCEDURE
- Several test substances were tested in parallel within the present test using the same control tissues (negative control, NC and positive control, PC).
- On the day of arrival in the laboratory, the tissues were transferred to sterile 6-well plates with 0.9 mL assay medium and preconditioned in the incubator at 37°C. After 1 hour the preincubation medium was replaced with fresh medium and preconditioning continued for 18 ± 3 hours.
- Three tissues were treated with the test substance, the PC and NC, respectively. In addition three killed control tissues were used for the test substance and NC, respectively, in order to detect direct MTT reduction.
- A nylon mesh was placed carefully onto the tissue surface of the NC, NC KC and PC after application.
- The tissues were kept under the laminar flow hood at room temperature for 25 minutes overall and for 35 minutes in the incubator.
- The tissues were washed with sterile PBS to remove residual test material 1 hour after start of application. Rinsed tissues were blotted on sterile absorbent paper and transferred into new 6-well plates, pre-filled with 0.9 mL fresh medium. When all tissues were rinsed, the surface of each tissue was carefully dried with a sterile cotton swab.
- Subsequently, the tissues were placed into the incubator at 37°C for 24 ± 2 hours.
- After 24 ± 2 hours the tissues were transferred into new 6-well plates pre-filled with 0.9 mL of fresh medium and placed into the incubator for additional 18 ± 2 hours post-incubation period.
- After the post-incubation period, the assay medium was replaced by 0.3 mL MTT solution and the tissues were incubated in the incubator for 3 hours. The tissues used as colour control were placed into assay medium without MTT.
- After incubation, the tissues were washed with PBS to stop the MTT-incubation. The formazan that was metabolically produced by the tissues was extracted by incubation of the tissues in isopropanol. The optical density at a wavelength of 570 nm (OD570) of the extracts was determined spectrophotometrically. Blank values were established of 4 microtiter wells filled with isopropanol for each microtiter plate.

DATA EVALUATION
- Principle: The OD570 values determined for the various tissues are measures of their viability. The quotient of the OD570 of tissues treated with the test material and the mean OD570 values of the NC (percent of control) is used for evaluating whether or not a test material is irritant.
- Calculation of individual and mean optical densities: The individual tissue OD570 is calculated by subtracting the mean blank value of the respective microtiter plate from the respective individual tissue OD570 value. The mean OD570 for a test group of three tissues treated in the same way is calculated.
- Application of measurements using killed control tissues: In case of direct reduction of MTT by the test substance, the OD570 values measured in the freeze-killed control tissues (KC) will be used to correct the mean OD570 of the test-substance treated tissues (mean OD570 KC corrected). Since killed tissue might still have a residual enzyme activity that is able to produce some formazan net OD570 KC is calculated by subtracting the OD570 KC of the NC from the OD570 KC of the test substance. In case the net OD570 KC is greater than zero it is subtracted from the respective mean OD570 to result in the mean OD570 KC corrected. The mean OD570 KC corrected represents the formazan production linked to the tissue viability and therefore indicates the cytotoxic potency of the test substance.
- Tissue viability: The quantification of tissue viability is presented as the quotient of the mean OD570 (or mean OD570 KC corrected, if applicable) divided by the respective OD570 NC value in percent for each exposure time.

ACCEPTANCE CRITERIA
In case one of the below given acceptance criteria was not met, repetition of the test was considered.
- Barrier function and Quality control (QC): The supplier demonstrates that each batch of the model used meets the defined production release criteria. MatTek determines the ET50 value following exposure to Triton X-100 (1%) for each EpiDermTM batch. The ET50 must fall within a range established based on a historical database of results. The following acceptability range (upper and lower limit) for the ET50 is established by the supplier as described in the cited OECD guidelines. Lower acceptance limit: ET50 = 4.0 hours; Upper acceptance limit: ET50 = 8.7 hours
- Acceptance criteria for the negative control (NC): The absolute OD570 of the negative control tissues in the MTT test is an indicator of tissue viability obtained in the testing laboratory after the shipping and storing procedure and under specific conditions of the assay. Tissue viability is acceptable if the mean OD570 of the NC is ≥ 0.8. The mean OD570 of the NC should not exceed 2.8.
- Acceptance criteria for the positive control (PC): 5% SDS is used as PC and reflects the sensitivity of the tissues used in the test conditions. A viability of ≤ 20% is acceptable.
- Acceptance criteria for the variability of the tissues: For every treatment three tissues are treated in parallel. The inter-tissue variability is considered to be acceptable if the SD of %-viability is ≤ 18%.
- Acceptance criteria for the killed controls (KC): The OD570 of the tissues for the KC of the NC should be ≤ 0.35. The OD570 value for direct MTT-reduction of a test substance should be ≤ 30% of the OD570 of the NC.
- Acceptance criteria for the colour controls (CC): The OD570 value for the colour control of a test substance should be ≤ 30% of the OD570 of the NC.

EVALUATION OF RESULTS
- Irritant potential of the test materials is predicted from the mean relative tissue viabilities compared to the negative control tissues concurrently treated with sterile PBS. A chemical is considered as "irritant", if the mean relative tissue viability with a test material is less than or equal to 50%.
- A single test composed of at least three tissue replicates should be sufficient for a test chemical when the result is unequivocal. However, in cases of borderline results, such as non-concordant replicate measurements and/or mean percent tissue viability equal to ±5% of the cut-off value, a second test should be considered, as well as a third one in case of discordant results between the first two tests.

DECISION CRITERIA
See table in 'Any other information on materials and methods incl. tables'
Control samples:
yes, concurrent negative control
yes, concurrent positive control
yes, concurrent MTT non-specific colour control
Amount/concentration applied:
TEST MATERIAL
25 µL sterile PBS was applied first. Thereafter, a bulk volume of ca. 25 µL (about 8 mg) of the solid test material was applied with a sharp spoon and homogeneously distributed together with the fluid.

CONTROLS
Control tissues were concurrently treated with 30 µL of sterile PBS (NC, NC KC) or with 30 µL of 5% SDS (PC) or test substance (KC). A nylon mesh was placed carefully onto the tissue surface of the NC, NC KC and PC afterwards.
Duration of treatment / exposure:
1 hour
Duration of post-treatment incubation (if applicable):
42 hour post-incubation period
Number of replicates:
Three tissues were treated with the test substance, the PC and NC, respectively. In addition three killed control tissues were used for the test substance and NC.
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
1 hour exposure
Value:
95.7
Vehicle controls validity:
not applicable
Negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: Viability after correction based on killed controls
Other effects / acceptance of results:
OTHER EFFECTS:
- Direct-MTT reduction: The results of the KC tissues indicate an increased MTT reduction (mean viability 0.6 % of NC). Thus for the test substance the final mean viability is given after KC correction.
- Colour interference with MTT: Based on the result of the pretest it was judged that application of colour control tissues is not necessary.

ACCEPTANCE OF RESULTS:
- Acceptance criteria for negative control are met.
- Acceptance criteria for positive control are met.
- Acceptance criteria for variability between replicate measurements are met.
Interpretation of results:
GHS criteria not met
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not 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
Study period:
09 Aug 2016 to 28 Jun 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
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)
Version / remarks:
28 July 2015
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Remarks:
BASF SE Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany
Specific details on test material used for the study:
- Name as cited in study report: Orasol Red 335
- Test-substance No.: 16/0125-1
- Batch identification: 002-141706
- Content: 96 g/100 g (100 g/100 g minus water content)
- Physical state / colour: Solid / red
- Storage conditions: Room temperature
Species:
human
Details on test animals or tissues and environmental conditions:
TISSUE MODEL
The EpiOcularTM model (OCL-200) is a three-dimensional non-keratinized tissue construct composed of normal human derived epidermal keratinocytes used to model the human corneal epithelium. The EpiOcularTM tissues (surface 0.6 cm²) are cultured on cell culture inserts (MILLICELLs®, 10 mm diameter) and are commercially available as kits (EpiOcular™ 200), containing 24 tissues on shipping agarose.
Tissue model: OCL-200
Tissue Lot Number: 23724
Supplier: MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia

MATERIALS AND TECHNICAL EQUIPMENT
- Laminar flow bench: HERAsafe KS 18 (Thermo ELECTRON CORPORATION)
- CO2 incubator: Heraeus BBD 6220
- Incubation conditions: 37°C ± 1°C, 5% ± 1% CO2, 90% ± 5% humidity
- Spectrophotometer: SunriseTM Absorbance Reader. For the determination of the optical density of colored extracts. Measurement using a filter wavelength 570 nm without reference filter
- EpiOcular™ OCL-200 kit: MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia containing: 24 OCL-200 tissues (reconstructed cornea): surface 0.6 cm² cultured in Millicells® (1 cm diameter)
- Tissue for MTT-reduction control: OCL-200 tissue that is killed by freezing at –20°C
- Assay medium: OCL-200-ASY assay medium
- MTT diluent: Dulbecco's modified eagle's medium (DMEM) based medium used for diluting MTT (MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia / Sigma, Germany)
- Pre-treatment / wash buffer: Dulbecco's phosphate buffered saline (PBS), w/o Ca2+, Mg2+ (MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia and Biochrom, Germany)
- Detection agent: 3-[4.5-dimethylthiazol-2-yl]-2.5-diphenyltetrazolium bromide (MTT) (MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia and Sigma, Germany), 1.0 mg / mL MTT diluent
- Extracting agent: Isopropanol p.a.
Vehicle:
unchanged (no vehicle)
Controls:
yes, concurrent positive control
yes, concurrent negative control
other: MTT reduction control: de-ionized water, sterile or test substance
Amount / concentration applied:
A bulk volume of ca. 50 µL (about 14 mg) of the test material or control substances was applied
Duration of treatment / exposure:
6 hours
Duration of post- treatment incubation (in vitro):
18 hours
Number of animals or in vitro replicates:
Duplicates
Details on study design:
DIRECT MTT REDUCTION
- To assess the ability of the test material to directly reduce MTT a pretest (experimental conduct in accordance with GLP but without a GLP status) was performed. The test substance was added to 0.9 mL of the MTT solution. The mixture was incubated in the dark at about 37 °C for 3 hours. A negative control (de-ionized water) was tested concurrently. If the MTT solution colour or, in case of water-insoluble test substances the border to the water-phase, turned blue / purple, the test substance was presumed to directly reduce MTT.
- The direct reduction of MTT by a test substance interferes with the colour density produced by metabolic capacity of the tissue and would falsify the test results.
- In case where direct MTT reduction occurred, two freeze-killed control (KC) tissues each were treated with the test article and the negative control, in the same way as described in the following section.
- Due to the ability of the test substance to reduce MTT directly, KC tissues were applied in parallel.

COLOUR CONTROL
- The colour of a test substance may interfere with the colour density produced by metabolic capacity of the tissue and would falsify the test results when residues of the test substance remain on the tissues after washing and are extracted by the isopropanol.
- Due to the colour of the test substance a pretest (experimental conduct in accordance with GLP but without a GLP status) was performed as follows: the test substance was applied to a KC tissue, incubated for 6 hours and removed by washing. Thereafter extraction in isopropanol was performed and the OD570 of the extract was determined spectrophotometrically.
- Based on the result of the pretest it was judged that application of colour control tissues is not necessary.

BASIC PROCEDURE
- Several test substances were tested in parallel within the present test using the same control tissues (negative control, NC and positive control, PC).
- Two tissues were treated with each, the test substance, the PC and the NC. In addition two killed tissues were used for each, the test substance and the NC, in order to detect direct MTT reduction.
- Further, colour controls were performed in order to differentiate formazan produced by the cells in the MTT test from colour residues of the test substance. Two further viable tissues (CC) and two further KCs (KC CC) were treated with the test substance. During MTT-incubation these CC-tissues were placed in medium without MTT.
- There are two separate protocols for liquids and solids, differing in exposure time and post incubation period. Due to the physical state of the test substance the protocol for solids was applied.

PRE-INCUBATION OF THE TISSUES
- On the day of arrival in the laboratory, the tissues were transferred to sterile 6-well plates with 1 mL assay medium and preconditioned in the incubator at 37°C. After 1 hour the preincubation medium was replaced with fresh medium and preconditioning continued in the incubator at standard culture conditions for 16 – 24 hours.

PRETREATMENT OF THE TISSUES
- After the pre-incubation, the tissues were pre-treated with 20 μL of PBS in order to wet the tissue surface. The tissues were incubated at standard culture conditions for 30 minutes.

APPLICATION OF THE TEST SUBSTANCE
- Using a sharp spoon, a bulk volume of ca. 50 µL of the test material was applied covering the whole tissue surface.
- Control tissues were concurrently applied with 50 µL of sterile de-ionized water (NC, NC KC) or with 50 µL of methyl acetate (PC) or test substance (KC, CC and KC CC).
- After application, the tissues were placed into the incubator until the total exposure time of 6 hours was completed.

REMOVAL OF THE TEST SUBSTANCE AND POSTINCUBATION PERIOD
- To remove the test substance, the tissues were washed with sterile PBS. For this purpose the tissues were immersed and swiveled three times in each of three beakers filled with PBS. Washed tissues were immediately immersed into 12-well plates, pre-filled with 5 mL/well prewarmed medium (post-soak immersion) in order to remove residual test substance. After 25 minutes of post-soak immersion, each tissue was dried on absorbent paper and transferred to fresh 6-well plates filled with 1 mL/well pre-warmed medium.
- Subsequently, the tissues were incubated at standard culture conditions for 18 hours (postincubation period).

MTT INCUBATION
- After the post-incubation period, the assay medium was replaced by 0.3 mL MTT solution and the tissues were incubated in the incubator for 3 hours.
- After incubation, the tissues were washed with PBS to stop the MTT-incubation.
- The formazan that was metabolically produced by the tissues was extracted by incubation of the tissues in isopropanol at room temperature overnight or for at least 2 hours on a plate shaker. The optical density at a wavelength of 570 nm (OD570) of the extracts was determined spectrophotometrically. Blank values were established of 4 microtiter wells filled with isopropanol for each microtiter plate.

METHODS FOR MEASURED ENDPOINTS
- Principle: The OD570 values determined for the various tissues are measures of their viability. The ratio of the OD570 of tissues treated with the test material and the mean OD570 values of the NC (percent of control) is used for evaluating whether or not a test material was an irritant.
- Calculation of individual and mean optical densities: The corrected measured OD570 value for each individual tissue was calculated by subtracting the mean blank value of the respective microtiter plate from the respective individual tissue OD570 value. The mean OD570 for a test group of two tissues treated in the same way was calculated.
- Application of measurements using killed control tissues: In case of direct reduction of MTT by the test substance, the OD570 values measured in the freeze-killed control tissues (KC) will be used to correct the mean OD570 of the test-substance treated tissues (mean OD570 KC corrected). Since killed tissue might still have a residual enzyme activity that is able to produce some formazan net OD570 KC is calculated by subtracting the OD570 KC of the NC from the OD570 KC of the test substance. In case the net OD570 KC is greater than zero it is subtracted from the respective mean OD570 to result in the mean OD570 KC corrected. The mean OD570 KC corrected represents the formazan production linked to the tissue viability and therefore indicates the cytotoxic potency of the test substance.
- Tissue viability: The quantification of tissue viability is presented as the ratio of the mean OD570 (or mean OD570 KC corrected, if applicable) divided by the respective OD570 NC value in percent.

ACCEPTANCE CRITERIA
- Barrier function and Quality control (QC): The supplier demonstrates that each batch of the model used meets the defined production release criteria. MatTek determines the ET50 (min) value following exposure to 100 μL of 0.3% Triton X-100 for each EpiOcularTM EIT (OCL-200) batch. The ET50 must fall within a range established based on a historical database of results. The following acceptability range (upper and lower limit) for the ET50 is established by the supplier as described in the cited OECD Guideline. Lower acceptance limit: ET50 = 12.2 min; Upper acceptance limit: ET50 = 37.5 min
- Acceptance criteria for the NC: The absolute OD570 of the NC-tissues in the MTT-test is an indicator of tissue viability obtained in the testing laboratory after the shipping and storing procedure and under specific conditions of the assay. Tissue viability is acceptable if the mean OD570 of the NC is > 0.8. The mean OD570 of the NC should not exceed 2.5.
- Acceptance criteria for the PC: Methyl acetate used as PC usually leads to a tissue viability of approx. 25%. A viability of < 50% is acceptable.
- Acceptance criteria for tissue variability: Two tissues were treated under the same conditions. A variability between the two tissues is considered to be acceptable if the relative difference of the viability is < 20%.
- Acceptance criteria for the KC: The OD570 of the killed control tissues treated as negative control should be ≤ 0.35. The value for direct MTTreduction of a test substance should be ≤ 30% of the NC.

EVALUATION OF RESULTS
- The irritation potential of the test materials is predicted from the mean relative tissue viabilities compared to the negative control tissues concurrently treated with sterile water. A chemical is considered as "irritant", if the mean relative tissue viability with a test material is less than or equal to 60%.
- A single test composed of at least two tissue replicates should be sufficient for a test chemical when the result is unequivocal. However, in cases of borderline results, such as nonconcordant replicate measurements and/or mean percent tissue viability equal to ±5% of the cut-off value, a second test should be considered, as well as a third one in case of discordant results between the first two tests.

DECISION CRITERIA
See table in 'Any other information on materials and methods incl. tables'
Irritation parameter:
other: cell viability
Run / experiment:
mean viability
Value:
108.7
Vehicle controls validity:
not applicable
Negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: viability after correction based on KC control
Other effects / acceptance of results:
ACCEPTANCE OF RESULTS:
- Acceptance criteria for negative control are met.
- Acceptance criteria for positive control are met.
- Acceptance criteria for variability between replicate measurements are met.
- Acceptance criteria for killed control tissues are met.

OTHER
- MTT reduction control: The results of the KC tissues indicate an increased MTT reduction (mean viability 7.0 % of NC). Thus for the test substance the final mean viability is given after KC correction.
Interpretation of results:
GHS criteria not met
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Skin irritation (OECD439)

The test substance was tested in vitro assays according to OECD439 and GLP principles. The cell viability in a reconstructed three dimensional human epidermis model (EpiDerm™) was evaluated following a single topical application of ca. 25 µL bulk volume of the undiluted test substance. Three EpiDerm™ tissues were incubated with the test substance for 1 hour followed by a 42-hours post-incubation period. Concurrent positive (5% SDS) negative (sterile PBS) freeze-killed control tissues for correction of direct MTT reduction were included. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/post-incubation using a colorimetric test. The reduction of mitochondrial dehydrogenase activity, measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the test-substance treated epidermal tissues is compared to that of negative control tissues. The quotient of the values indicates the relative tissue viability. The final mean viability of the test substance treated tissues determined in the irritation test was 95.7% (corrected for killed controls). Based on these results the test substance is not considered to be irritating to the skin (BASF 2017).

Eye irritation (OECD492)

In order to assess the eye irritating properties of the substance, The EpiOcular Eye Irritation Test was performed according to OECD guideline 492 under GLP principles. The potential of the test substance to cause ocular irritation was assessed by a single topical application of ca. 50 µL bulk volume of the undiluted test substance to a reconstructed three-dimensional human cornea model (EpiOcular™). Two EpiOcular™ tissues were incubated with the test substance for 6 hours followed by an 18-hours post-incubation period. Concurrent positive (neat methyl acetate) negative (sterile de-ionized water) freeze-killed control tissues for correction of direct MTT reduction were included. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/post-incubation using a colorimetric test. The reduction of mitochondrial dehydrogenase activity, measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the test-substance treated epidermal tissues is compared to that of negative control tissues. The ratio of the values indicates the relative tissue viability. The final mean viability of the test-substance treated tissues (after correction for killed controls) was 108.7%. Based on these results the test substance is not considered to be irritating to the eyes (BASF 2017).

Justification for classification or non-classification

Based on the available information classification for skin and eye irritation of the substance is not warranted, in accordance with EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation No. (EC) 1272/2008.