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Diss Factsheets
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EC number: 202-196-5 | CAS number: 92-84-2
- 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
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Dissociation constant
Administrative data
Link to relevant study record(s)
- Endpoint:
- dissociation constant
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 112 (Dissociation Constants in Water)
- Deviations:
- yes
- Remarks:
- Only preliminary tests
- GLP compliance:
- yes (incl. QA statement)
- Dissociating properties:
- not determined
- Remarks on result:
- not determinable because of methodological limitations
- Conclusions:
- According to OECD Test Guideline 112, Dissociation constants in water (1981), no dissociation constant at 20 °C of the test item Phenothiazin D Prills could be determined in the pH range of 1 to 13.
Reference
As Phenothiazine is practically insoluble in water (0.127 mg/l) it was not possible to carry out the titration method.
For the spectrometric method methanol was used as solubiliser. For this, UV/VIS activity of the test item is tested at different pH-values in order to find a wavelength at which the ionised and unionised forms of the compound have appreciably different extinction coefficients.
Despite the high amount of solubilizer (10 % of the solution) it was not possible to dissolve the test item completely. The UV/VIS spectra were measured quickly after preparation of each solution as the test item precipitated slowly. Over time the solution became slightly turbid.
In the UV/VIS spectra of the test item at pH values of 1, 2, 6, 12 and 13 two distinct absorption maxima can be observed at 250 nm and approx. 312 nm. When KOH (c = 0.1 mol/L) is added the solution changes colour from transparent to pink within approx. 10 min. This change is reflected in the UV/VIS spectrum.
The test item appears to decompose at high pH-values (pH approx. 13) as several new bands are detected in the UV/VIS spectrum.
Overall, the absorption spectra show no consistent trend of the absorption of the bands at 312 nm and 250 nm over the tested pH range. While the absorption at both wavelengths is at its maximum at pH 1, the absorption minimum is reached at pH 6 and the absorptions of the solutions with pH 12 and 13 can be found between those of pH 2 and 6. Thus, it is impossible to identify at which pH value the ionised and the unionised form are present.
From these measurements and considering that the test item decomposes at high pH-values neither the dissociation constant nor the start of dissociation can be determined.
The spectrometric method is not applicable for the determination of the dissociation constant.
Description of key information
According toOECD Test Guideline 112, Dissociation constants in water (1981), no dissociation constant at 20 °C of the test itemPhenothiazinD Prills could be determined in the pH range of 1 to 13.
Key value for chemical safety assessment
Additional information
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.
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