Registration Dossier
Registration Dossier
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 208-904-9 | CAS number: 546-56-5
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data

Endpoint summary
Administrative data
Description of key information
In the first key in vitro skin irritation study with octaphenylcyclotetrasiloxane (CAS 546-56-5) using EpiDermTM tissue, the reported mean relative tissue viability (% negative control) was > 50 % (91.4 %) after 60 minutes treatment and 42 hours post-incubation (Eurofins, 2017).
In the second key in vitro skin irritation study with octaphenylcyclotetrasiloxane (CAS 546-56-5) using EpiSkinTM tissue, the reported mean relative tissue viability (% negative control) was > 50 % (104.9 %) after 15 minutes treatment and 42 hours post-incubation (Eurofins, 2017a).
In the key in vitro Bovine Corneal Opacity and Permeability Assay, conducted according to an appropriate OECD test guideline and in compliance with GLP, the in vitro irritation score reported for the test substance, octaphenylcyclotetrasiloxane, was < 3. The test substance was concluded to be not irritating to eyes (Eurofins, 2017).
Key value for chemical safety assessment
Skin irritation / corrosion
Link to relevant study records
- Endpoint:
- skin irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2 March 2017 to 24 April 2017
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)
- Version / remarks:
- 2015
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Specific details on test material used for the study:
- STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle:
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: 25 µL of sterile DPBS was applied to the epidermal surface in order to improve the contact between the powder and the epidermis. Afterwards, 25 mg (39 mg/cm2) of the test item was applied directly atop the EpiDermTM tissue using an application spoon avoiding compression of the test item. The test item was spread to match size of the tissue by gently shaking the inserts or by using a bulb-headed Pasteur pipette.
- Preliminary purification step (if any): not specified - Test system:
- human skin model
- Source species:
- human
- Cell type:
- non-transformed keratinocytes
- Cell source:
- other: not specified
- Source strain:
- not specified
- Details on animal used as source of test system:
- Not applicable
- 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)
- Details on test system:
- RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EpiDerm™
- Tissue batch number(s): 25086
- Production date: not specified
- Shipping date: not specified
- Delivery date: not specified
- Date of initiation of testing: not specified
TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 +/- 1 °C, 5.0% CO2
- Temperature of post-treatment incubation (if applicable): 37 +/- 1 °C, 5.0% CO2
REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: The tissues were washed by filling and emptying the inserts 15 times with DPBS using a constant stream in about 1.5 cm distance from the tissue surface.
- Observable damage in the tissue due to washing: No damage specified.
- Modifications to validated SOP: Not specified
MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 5 mg/mL MTT
- Incubation time: 3 h +/- 5 min at 37 +/- 1 °C, 5.0% CO2, humidified to 95%.
- Spectrophotometer: plate spectrophotometer using isopropanol as a blank.
- Wavelength: 570 nm
- Filter: OD was measured at 570 nm with a filter band pass of maximum ± 30 nm without reference wavelength.
- Filter band width: Not specified
- Linear OD range of spectrophotometer: yes
FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability: 1.581+/-0.238, acceptance criteria OD (540-570 nm) [1.0-3.0]
- Barrier function: 5.58 h, acceptance criteria ET-50 [4.77-8.72 h]
- Morphology: not specified
- Contamination: No contamination was detected.
- Reproducibility: Not specified.
NUMBER OF REPLICATE TISSUES: Triplicate tissues
CONTROL TISSUES USED IN CASE OF MTT DIRECT INTERFERENCE
- Fresh tissues / killed tissues: killed tissues
- Procedure used to prepare the killed tissues (if applicable): not specified
- N. of replicates : duplicate
- Method of calculation used: NSMTT (non-specific MTT) was then calculated relative to the negative control of living tissues (NK) according to the following formula:
NSMTT [%] = [(ODKT - ODKU)/ODNK] * 100
If the test item is classified as non-irritant and if non-specific MTT reduction is ≤ 30% relative to the negative control of living epidermis, the true MTT metabolic conversion (TODTT) of the test item treated living tissues TM was corrected according to the following formula:
TODTT = ODTM – (ODKT – ODKU)
NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION: One
PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be corrosive to skin if the mean relative tissue viability after 1 hour exposure is less than 50%.
- The test substance is considered to be non-corrosive to skin if the mean relative tissue viability after 1 hour exposure is greater than or equal to 50%.
- Justification for the selection of the cut-off point(s) if different than recommended in TG 431 and 439: not applicable - Control samples:
- yes, concurrent positive control
- other: Negative control: Dulbecco’s phosphate buffered saline (DPBS);
- Amount/concentration applied:
- TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 25 mg + 25 µL DPBS
NEGATIVE CONTROL
- Concentration (if solution): 30 µL DPBS
POSITIVE CONTROL
- Concentration (if solution): 30 µL 5% SDS solution - Duration of treatment / exposure:
- 60 min
- Duration of post-treatment incubation (if applicable):
- 42 hours
- Number of replicates:
- Triplicate tissues were used.
- Irritation / corrosion parameter:
- % tissue viability
- Run / experiment:
- No 1 expressed in percentage of negative control
- Value:
- > 50
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Other effects / acceptance of results:
- - OTHER EFFECTS:
- Visible damage on test system: none observed
- Direct-MTT reduction: The test item showed no non-specific reduction of MTT. Therefore, no additional controls were necessary.
- Colour interference with MTT: The test item showed no colouring after mixture with aqua dest. and isopropanol.
DEMONSTRATION OF TECHNICAL PROFICIENCY:
- Mean Absolute OD570 nm Negative control (NC): 2.038, cut off 0.8 ≤ NK ≤ 2.8
- Relative Viability [%] Positive control (PC): 3.5, cut off ≤ 20%
- SD Viability [%]: 0.2 – 4.9, cut off ≤ 18%
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
- Range of historical values if different from the ones specified in the test guideline: not applicable - Interpretation of results:
- GHS criteria not met
- Conclusions:
- In the in vitro skin irritation study with octaphenylcyclotetrasiloxane (CAS 546-56-5) using EpiDermTM tissue, the reported mean relative tissue viability (% negative control) was > 50 % (91.4 %) after 60 minutes treatment and 42 hours post-incubation.
- Endpoint:
- skin irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 27 March 2017 to 07 April 2017
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)
- Version / remarks:
- 2015
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Specific details on test material used for the study:
- STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle:
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: 5 µL distilled water (aqua dest.) was applied to the epidermal surface in order to improve further contact between the powder and the epidermis. The water was gently spread on the surface. Afterwards, approximately 10 ± 2 mg (26.3 mg/cm²) of the powder was applied to the epidermis surface. - Test system:
- human skin model
- Source species:
- human
- Cell type:
- non-transformed keratinocytes
- Cell source:
- other: not specified
- Source strain:
- not specified
- Details on animal used as source of test system:
- Not applicable
- Justification for test system used:
- This test uses the EPISKIN-SM™ reconstructed human epidermis model (SkinEthic) 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 skin, i.e. the epidermis.
- Vehicle:
- unchanged (no vehicle)
- Details on test system:
- RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EPISKIN-SM™
- Tissue batch number(s): 17-EKIN-014
- Production date: not specified
- Shipping date: not specified
- Delivery date: not specified
- Date of initiation of testing: not specified
TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: at room temperature for 15 +/- 0.5 min
- Temperature of post-treatment incubation (if applicable): 37 +/- 1 °C, 5.0% CO2 for 42 +/- 1 h.
REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: The tissues were washed with DPBS to remove any residual test item. Excess DPBS was removed by blotting bottom with blotting paper.
- Observable damage in the tissue due to washing: None reported
- Modifications to validated SOP: None reported
MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 3 mg/mL MTT
- Incubation time: 3 hours
- Spectrophotometer: yes
- Wavelength: at 570 nm
- Filter: filter band
- Filter bandwidth: filter band pass of maximum ± 30 nm in a plate spectrophotometer
- Linear OD range of spectrophotometer: yes
FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability: not specified
- Barrier function: IC50 determination (SDS concentration, MTT test, n = 14): Specification ≥ 1.5 mg/mL; Result: 2.2 mg/mL
- Morphology: Specification ≥ 19.5; Result: 22.3 ± 1.0, CV = 4.7%; Well-differentiated epidermis consisting of a basal layer, several spinous and granular layers and a thick stratum corneum.
- Contamination: No contamination was reported.
- Reproducibility: not specified
NUMBER OF REPLICATE TISSUES: Triplicate tissues
CONTROL TISSUES USED IN CASE OF MTT DIRECT INTERFERENCE
- Fresh tissues / killed tissues: Killed tissues
- Procedure used to prepare the killed tissues (if applicable): not specified
- N. of replicates : triplicate
- Method of calculation used: NSMTT (non-specific MMT) was calculated relative to the negative control of living tissues (NK) per treatment period according to the following formula:
NSMTT [%] = [(ODKT - ODKU)/ODNK] * 100
If non-specific MTT reduction was ≤ 30% relative to the negative control of living epidermis, the true MTT metabolic conversion (TODTT) of the test item treated living tissues (TM) was corrected according to the following formula:
TODTT = ODTM - (ODKT - ODKU)
NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION:
PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be irritant to skin if the viability after 15 minutes exposure is less than 50%.
- The test substance is considered to be non-corrosive to skin if the viability after 15 minutes exposure is greater than or equal to 50%.
- Justification for the selection of the cut-off point(s) if different than recommended in TG 431 and 439: not applicable - Control samples:
- yes, concurrent negative control
- yes, concurrent positive control
- Amount/concentration applied:
- TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10 ± 2 mg + 5 µL aqua dest
NEGATIVE CONTROL
- Concentration (if solution): 10 µL DPBS
POSITIVE CONTROL
- Concentration (if solution): 10 µL 5% SDS solution - Duration of treatment / exposure:
- 15 minutes
- Duration of post-treatment incubation (if applicable):
- 42 hours
- Number of replicates:
- Triplicate
- Irritation / corrosion parameter:
- % tissue viability
- Run / experiment:
- Experiment I
- Value:
- > 50
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Other effects / acceptance of results:
- - OTHER EFFECTS:
- Visible damage on test system: none reported
- Direct-MTT reduction: The test item showed no non-specific MTT reducing potential, therefore no additional controls for correction of results were necessary.
- Colour interference with MTT: The test item showed no colouring potential, therefore no additional controls for correction of results were necessary.
DEMONSTRATION OF TECHNICAL PROFICIENCY:
- Mean OD570 nm Blank: value 0.044; cut off < 0.1;
- Mean Absolute OD570 nm NK: 0.610, cut off 0.6 ≤ NK ≤1.5;
- Mean Relative Viability [%] PC: 9.8; cut off ≤ 40%;
- Max. SD of % Viability [%]: 8.1, cut off ≤ 18%
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
- Range of historical values if different from the ones specified in the test guideline: not applicable - Interpretation of results:
- GHS criteria not met
- Conclusions:
- In the in vitro skin irritation study with octaphenylcyclotetrasiloxane (CAS 546-56-5) using EpiSkinTM tissue, the reported mean relative tissue viability (% negative control) was > 50 % (104.9 %) after 15 minutes treatment and 42 hours post-incubation.
Referenceopen allclose all
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not irritating)
Eye irritation
Link to relevant study records
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 30th May 2017 to 07th June 2017
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)
- Version / remarks:
- 2013
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Specific details on test material used for the study:
- STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: the test substance was stable in corn oil
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: not applicable
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test material was suspended with corn oil to give 20% concentration.
- Preliminary purification step (if any): not specified - Species:
- other: animals freshly slaughtered at the abattoir
- Strain:
- not specified
- Details on test animals or tissues and environmental conditions:
- SOURCE OF COLLECTED EYES
- Source: animals freshly slaughtered at the abattoir A. Moksel AG, Buchloe, Germany
- Number of animals: not specified
- Characteristics of donor animals (e.g. age, sex, weight): not specified
- Storage, temperature and transport conditions of ocular tissue (e.g. transport time, transport media and temperature, and other conditions): On the test day, fresh eyes were collected from the slaughterhouse and were transported in HBSS containing Pen/Strep on ice to the laboratories.
- Time interval prior to initiating testing: Immediately after arrival of the eyes, cornea preparation was initiated.
- indication of any existing defects or lesions in ocular tissue samples: The eyes were carefully examined for defects and any defective eyes were discarded.
- Indication of any antibiotics used: Not specified - Vehicle:
- other: corn oil
- Controls:
- yes, concurrent vehicle
- yes, concurrent positive control
- yes, concurrent negative control
- Amount / concentration applied:
- TEST MATERIAL
- Concentration (if solution): 750 µL of the test item preparation
VEHICLE
- Amount(s) applied (volume or weight with unit):
- Concentration (if solution): 750 µL - Duration of treatment / exposure:
- 4 hours ± 5 minutes incubation at 32 ± 1 °C.
- Duration of post- treatment incubation (in vitro):
- 90 minutes at 32 ± 1 °C
- Number of animals or in vitro replicates:
- 3 corneas for test item
- Details on study design:
- SELECTION AND PREPARATION OF CORNEAS: The assay uses isolated corneas obtained as a by-product from animals freshly slaughtered at the abattoir A. Moksel AG, Buchloe, Germany. The tissue surrounding the eyeball was carefully pulled away and the cornea was excised leaving a 2 to 3 mm rim of sclera. The isolated corneas were stored in a petri dish containing HBSS.The corneas were mounted in corneal holders with the endothelial side against the O-ring of the posterior chambe. The anterior chamber was then positioned on top of the cornea and tightened with screws. The chambers of the corneal holder were then filled with RPMI (without phenol red) containing 1% FBS and 2 mM L-glutamine (complete RPMI). The posterior chamber was always filled first. The corneas were incubated for one hour at 32 ± 1 °C.
QUALITY CHECK OF THE ISOLATED CORNEAS: The corneas were visually examined for defects and any defective cornea had been discarded.
NUMBER OF REPLICATES: Triplicate
NEGATIVE CONTROL USED: Yes, physiological saline 0.9% NaCl
SOLVENT CONTROL USED (if applicable): Yes, corn oil
POSITIVE CONTROL USED: Yes, imidazole 20% in physiological saline 0.9% NaCl
APPLICATION DOSE AND EXPOSURE TIME: 750 µL for 4 hours ± 5 minutes incubation at 32 ± 1 °C.
TREATMENT METHOD: closed chamber method
POST-INCUBATION PERIOD: yes, 90 minutes at 32 ± 1 °C
REMOVAL OF TEST SUBSTANCE
- Number of washing steps after exposure period: The test substance or the control substance was removed and the epithelium washed at least three times with MEM
- POST-EXPOSURE INCUBATION: yes, 90 minutes at 32 ± 1 °C
METHODS FOR MEASURED ENDPOINTS:
- Corneal opacity: The following formula was used to calculate the opacity: Opacity= (Io/Iᵦ)/a. The value Io is the illuminance through a holder without cornea, but with windows and liquid. This value is determined by taking the mean for a set of cornea holders and is reevaluated periodically.
- Corneal permeability: passage of sodium fluorescein dye measured with the aid of OD490 using a spectrophotometer
- Others (e.g, pertinent visual observations, histopathology): (please specify)
SCORING SYSTEM: In Vitro Irritancy Score (IVIS)
DECISION CRITERIA: The decision criteria as indicated in the TG was used. - Irritation parameter:
- in vitro irritation score
- Run / experiment:
- bovine corneal opacity and permeability assay
- Value:
- 1.55
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Other effects / acceptance of results:
- OTHER EFFECTS:
- Visible damage on test system: None reported
DEMONSTRATION OF TECHNICAL PROFICIENCY: The in vitro irritation score obtained with the positive control fell within the two standard deviations of the current historical mean and therefore this assay was considered to be valid.
ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Range of historical values if different from the ones specified in the test guideline: not applicable - Interpretation of results:
- GHS criteria not met
- Conclusions:
- In the in vitro Bovine Corneal Opacity and Permeability Assay, conducted according to an appropriate OECD test guideline and in compliance with GLP, the in vitro irritation score reported for the test substance, octaphenylcyclotetrasiloxane, was < 3. The test substance was concluded to be not irritating to eyes.
Reference
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not irritating)
Respiratory irritation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Additional information
The potential of octaphenylcyclotetrasiloxane (CAS 546-56-5) to induce skin irritation was analysed by using a three-dimensional human epidermis model EpiDermä(MatTek) comprising a reconstructed epidermis with a functional stratum corneum (Eurofins, 2017).
The test substance was applied topically to the EpiDermä 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 non-specific reduction of MTT and no colouring after mixture with aqua dest. and isopropanol. Therefore, no additional controls were necessary. The test item showed no irritant effects. The mean relative tissue viability (% negative control) was> 50% (91.4%) after 60 min treatment and 42 h post-incubation. The controls confirmed the validity of the study.
The potential of octaphenylcyclotetrasiloxane (CAS 546-56-5) to induce skin irritation was also analysed by using the three-dimensional human skin model EPISKIN-SM comprising a reconstructed epidermis with a functional stratum corneum (Eurofins, 2017a). The test substance was applied topically to the EPISKIN-SM for 15 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 non-specific MTT reducing potential and no colouring potential, therefore no additional controls for correction of results were necessary. The test item showed no irritant effects. The mean relative tissue viability (% negative control) was> 50% (104.9%) after 15 min treatment and 42 h post-incubation. The controls confirmed the validity of the study.
The eye irritancy potential of octaphenylcyclotetrasiloxane (CAS 546-56-5) was investigated in the bovine corneal opacity and permeability assay. The test item was suspended with corn oil to give a 20% concentration. 750 µL of the test item preparation or the control substance was introduced into the anterior chamber (closed-chamber method). After 4 hours ± 5 minutes incubation at 32 ± 1 °C either the test substance or the control substance was removed and the epithelium washed at least three times with MEM. Once the medium was free of test substance, the cornea was finally rinsed with complete RPMI (without phenol red). The anterior chamber was refilled with complete RPMI and an illuminance measurement was performed. Also, each cornea was observed visually and pertinent observations were recorded. Then the corneas were incubated for 90 minutes at 32±1 °C. Then the medium from the posterior chamber was removed and its optical density at 490 nm (OD490) was determined, using a spectrophotometer.
The calculated in vitro irritation score was calculated to be 1.55. The in vitro irritation score obtained with the positive control fell within the two standard deviations of the current historical mean and therefore this assay is considered to be valid. The negative control responses should result in opacity and permeability values that are less than the established upper limits for background bovine corneas treated with the respective negative control.
Justification for classification or non-classification
Based on the available data for octaphenylcyclotetrasiloxane (CAS 546-56-5), no classification for skin and eye irritation is required according to Regulation (EC) No 1272/2008.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.

EU Privacy Disclaimer
This website uses cookies to ensure you get the best experience on our websites.