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Diss Factsheets
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EC number: 231-137-6 | CAS number: 7440-27-9
- 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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Short-term toxicity to aquatic invertebrates
Administrative data
Link to relevant study record(s)
- Endpoint:
- short-term toxicity to aquatic invertebrates
- Data waiving:
- other justification
- Justification for data waiving:
- other:
- Justification for type of information:
- In accordance with column 2 of REACH Annex VII the study does not need to be conducted if there
are mitigating factors indicating that aquatic toxicity is unlikely to occur, for instance if the substance is
highly insoluble in water or unlikely to cross biological membranes. In aqueous solution „free“ Terbium metal is converted to Terbiumhydroxide. Terbiumhydroxide is insoluble in water. Since Terbium (and its alloys) are only sparingly soluble in water (in aqueous solution „free“ Terbium metal is
converted to Terbiumhydroxide) and crossing of Terbium cations through biological membranes is
unlikely (fat barrier) and therefore bioavailability is insignificant.
Furthermore the permanent magnets production with Terbium alloys takes place under strictly controlled conditions (vacuum, inert gas; see technological process) in order to ensure the high quality of the permanent magnets.
In addition the study is technically not feasible: Application of Terbium in massive form, which would be a prerequisite for toxicological and eco-toxicological studies, is practically not feasible. For this
purpose at least Terbium powder would be required (see REACH Annex XI (2)).
The Lanthanide elements own a very high affinity for oxygen; they exhibit the highest free energy for
oxide formation of all elements in the periodic table, accounting for the exceptional thermodynamic stability of the oxides. In consequence the metals will react with air, building up an oxide layer on the surface. This implies the technical unfeasibility of exposure to “free” Terbium metal (powder form), which is a prerequisite for the requested biological tests. Due to its reductive power and vigorous reaction with water appropriate application of Terbium metal (powder form) is technically not possible. In aqueous solution „free“ Terbium metal is converted to Terbiumhydroxide. Terbiumhydroxide is insoluble in water as can be shown from the water solubility data in section 4.8. Furthermore the study is scientifically unjustified: Human and/or environmental exposure to elementa l Terbium in massive form can be excluded, since at environmental conditions (presenve of air/humidity) practically insoluble substances (oxides, hydroxides) are formed immediately on the surface: Any respective investigations would be of no additional merit for the relevant scientific knowledge with regard to human and/or environmental protection.
In aqueous solution „free“ Terbium metal (powder form) is converted to Terbiumhydroxide.
Terbiumhydroxide is insoluble in water.
Reference
Description of key information
In accordance with column 2 of REACH Annex VII the study does not need to be conducted if there are mitigating factors indicating that aquatic toxicity is unlikely to occur, for instance if the substance is highly insoluble in water or unlikely to cross biological membranes. In aqueous solution „free“ Terbium metal is converted to Terbiumhydroxide. Terbiumhydroxide is insoluble in water. Since Terbium (and its alloys) are only sparingly soluble in water (in aqueous solution „free“ Terbium metal is converted to Terbiumhydroxide) and crossing of Terbium cations through biological membranes is unlikely (fat barrier) and therefore bioavailability is insignificant. Furthermore the permanent magnets production with Terbium alloys takes place under strictly co ntrolled conditions (vacuum, inert gas; see technological process) in order to ensure the high quality of the permanent magnets. In addition the study is technically not feasible: Application of Terbium in massive form, which would be a prerequisite for toxicological and eco-toxicological studies, is practically not feasible. For this purpose at least Terbium powder would be required (see REACH Annex XI (2)). The Lanthanide elements own a very high affinity for oxygen; they exhibit the highest free energy for oxide formation of all elements in the periodic table, accounting for the exceptional thermodynamic stability of the oxides. In consequence the metals will react with air, building up an oxide layer on the surface. This implies the technical unfeasibility of exposure to “free” Terbium metal (powder form), which is a prerequisite for the requested biological tests. Due to its reductive power and vigorous reaction with water appropriate application of Terbium metal (powder form) is technically not possible. In aqueous solution „free“ Terbium metal is converted to Terbiumhydroxide. Terbiumhydroxide is insoluble in water, as can be shown from the water solubility data in section 4.8.
Furthermore the study is scientifically unjustified: Human and/or environmental exposure to elementa l Terbium in massive form can be excluded, since at environmental conditions (presenve of air/humidity) practically insoluble substances (oxides, hydroxides) are formed immediately on the surface: Any respective investigations would be of no additional merit for the relevant scientific knowledge with regard to human and/or environmental protection. In aqueous solution „free“ Terbium metal (powder form) is converted to Terbiumhydroxide. Terbiumhydroxide is insoluble in water.
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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