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EC number: 244-344-1 | CAS number: 21351-79-1
- 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
Short-term toxicity to fish
Administrative data
Link to relevant study record(s)
Description of key information
Under the conditions of this acute fish toxicity study the observed endpoints for the effect of cesium hydroxide monohydrate were the following: 96h NOEC value: ≥ 100 mg test item/L; 96h LOEC value: > 100 mg test item/L and 96h LC50 value: > 100 mg test item/L. Based on these data the calculated values of 96h-LC50, 96h-LOEC and 96h-NOEC for cesium hydroxide anhydrous are greater than 89.3 mg/L.
Key value for chemical safety assessment
Fresh water fish
Fresh water fish
- Effect concentration:
- 100 mg/L
Additional information
Acute toxicity of the test item was assessed with Acute Fish Toxicity Test on Zebrafish (Danio rerio) over an exposure period of 96 hours in a static system. The recorded effects were mortality and symptoms of intoxication of the fish. Based on the results of a preliminary range finding test, a limit test was performed: one control and the concentration of 100 mg/L of the test item were tested according to the relevant guideline (OECD 203). Both test groups comprised seven zebrafish and 5 L test solution. No replicates were tested. The test was considered to be valid because assay acceptance criteria were fulfilled. Analytical determination of the test concentration was performed by flame photometry.
Based on the analytical results, the test concentration did not differ from the nominal concentration significantly, hence the biological results are based on the nominal concentration of 100 mg/L. No mortality or clinical symptoms were observed in the control. Clinical symptoms (increased motility of operculum, unbalanced swimming, localisation under the water surface, thrashing toward the bottom) was observed on 1 fish from the 7 in the 100 mg/L test item treated group at the 24 hours observation time. Although mortality (1/7 fish) was observed on the subsequent day (at the 48 hours observation time) in this group, this was within the assay acceptance criteria (one animal can die in the control group). Hence the test was considered to be valid and the mortality observed was not taken into consideration during evaluation of the results.
Under the conditions of this acute fish toxicity study the observed endpoints for the effect of cesium hydroxide monohydrate were the following: 96h NOEC value: ≥ 100 mg test item/L; 96h LOEC value: > 100 mg test item/L and 96h LC50 value: > 100 mg test item/L.
Based on these data the calculated values of 96h-LC50, 96h-LOEC and 96h-NOEC for cesium hydroxide anhydrous are greater than 89.3 mg/L.
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