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EC number: 235-227-6 | CAS number: 12136-45-7
- 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

Toxicological Summary
- Administrative data
- Workers - Hazard via inhalation route
- Workers - Hazard via dermal route
- Workers - Hazard for the eyes
- Additional information - workers
- General Population - Hazard via inhalation route
- General Population - Hazard via dermal route
- General Population - Hazard via oral route
- General Population - Hazard for the eyes
- Additional information - General Population
Administrative data
Workers - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 15.83 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 79.13 mg/m³
- Explanation for the modification of the dose descriptor starting point:
- The oral dose for the rat is converted to the corresponding air concentration using a standard breathing volume for the rat (1.15 m3/kg for 24 hours exposure. The resulting air concentration needs to be additionally corrected for 24 hlight activity (20 m3), assuming 100 % absorption for both routes. NOAEL rat 1820 mg/kg bw/day ÷1.15 m3/kgbw ÷20m3/rat NOAECrat 79.13 mg/m3
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 15.83 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- DNEL extrapolated from long term DNEL
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 79.13 mg/m³
- Explanation for the modification of the dose descriptor starting point:
- The oral dose for the rat is converted to the corresponding air concentration using a standard breathing volume for the rat (1.15 m3/kg for 24 hours exposure. The resulting air concentration needs to be additionally corrected for 24 hlight activity (20 m3), assuming 100 % absorption for both routes. NOAEL rat 1820 mg/kg bw/day ÷1.15 m3/kgbw ÷20m3/rat NOAECrat 79.13 mg/m3
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 15.83 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- Dose descriptor:
- NOAEC
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 15.83 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- DNEL extrapolated from long term DNEL
- Dose descriptor starting point:
- NOAEC
Workers - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 9.1 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 45.5 mg/kg bw/day
- Explanation for the modification of the dose descriptor starting point:
- There are no dermal repeated studies available. For dermal exposure we taken that: -the average weight of rats is 250g (200-300g), -the dose is applied over an area which is approximately 10% of the total body surface=0.025 kg corrected dermal NOAEL= oral NOAEL 1820 mg/kg bw/day x 0.025 kg = NOAELrat = 45.5 mg/kg bw/day
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 200 mg/kg bw/day
- Most sensitive endpoint:
- acute toxicity
- Route of original study:
- Dermal
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 1 000 mg/kg bw/day
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 1.124 mg/cm²
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- Dose descriptor:
- other: NOAEL
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 1.124 mg/cm²
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 5
- Dose descriptor starting point:
- other: NOAEL
Workers - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- high hazard (no threshold derived)
Additional information - workers
Potassium oxide/ Dipotassium oxide
Workers
Humans differ in sensitivity due to a number of biological factors (such as age, gender, genetic composition and nutritional status). The intraspecies variation in humans is greater than in the more homogeneous experimental animal population.
The data from animal studies are the starting point for risk characterisation.The default assumption in general is that humans are more sensitive than experimental animals.The traditional default AF(Assessment factor) suggested for interspecies extrapolation is 5 for workers and 10 for general population should be applied to the concentration/dose descriptor.
A lower default factor is generally suggested for the worker population, because the very young and very old are not part of this population.
To cover the intra-species variation, the default AF (Assessment factor) of 5 for workers was applied to the concentration/dose descriptor (NOAEL or NOAEC).
The dose descriptor for dermal irritation/corrosion come from dermal repeated study. In this study, the dose is reported in the unit mg/kg of body weight/day. This needs to be modified to enable comparison with the human exposure, generally expressed in mg/cm2/day.
We have taken that:
• the average weight of rats is 250g (200-300g), and the average weight of rabbit is 2.5 kg used by Merkel, D.J., N. 2000.
• the dose is applied over an area which is approximately 10% of the total body surface, and
• the total body surface of rats is on the average 445 cm2 (363 to 527 cm2) used by Merkel, D.J., N. 2000..
The generic modification from the NOAELtest (in mg/kg of body weight) to NOAELmodified (in mg/cm2/day) will be
NOAELin mg/cm2 = ((dose in mg/kg bw)x (average animal weight in kg)) / Treated surface in cm2)
NOAELtest* 0.25/44.5= NOAELmodified
The highest dose not causing irritation/corrosion was 1000 mg/kg bw in dermal toxicity study in rats of Merkel, D.J., N. 2000.
the modified dose descriptor would be
NOAELmodified =1000 mg/kg*0.25 kg/44.5cm2=5.62 mg/cm2
General Population - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 7.913 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 79.13 mg/m³
- Explanation for the modification of the dose descriptor starting point:
- The oral dose for the rat is converted to the corresponding air concentration using a standard breathing volume for the rat (1.15 m3/kg for 24 hours exposure. The resulting air concentration needs to be additionally corrected for 24 hlight activity (20 m3), assuming 100 % absorption for both routes. NOAEL rat 1820 mg/kg bw/day ÷1.15 m3/kgbw ÷20m3/rat NOAECrat 79.13 mg/m3
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 7.9 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- DNEL extrapolated from long term DNEL
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 79.13 mg/m³
- Explanation for the modification of the dose descriptor starting point:
- The oral dose for the rat is converted to the corresponding air concentration using a standard breathing volume for the rat (1.15 m3/kg for 24 hours exposure. The resulting air concentration needs to be additionally corrected for 24 hlight activity (20 m3), assuming 100 % absorption for both routes. NOAEL rat 1820 mg/kg bw/day ÷1.15 m3/kgbw ÷20m3/rat NOAECrat 79.13 mg/m3
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 7.913 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- Dose descriptor:
- NOAEC
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 7.913 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- DNEL extrapolated from long term DNEL
- Dose descriptor starting point:
- NOAEC
General Population - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 4.55 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Dermal
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 45.5 mg/kg bw/day
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 100 mg/kg bw/day
- Most sensitive endpoint:
- acute toxicity
- Route of original study:
- Dermal
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 1 000 mg/kg bw/day
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.562 mg/cm²
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- Dose descriptor:
- other: NOAEL
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.562 mg/cm²
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- Dose descriptor starting point:
- other: NOAEL
General Population - Hazard via oral route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 182 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 1 820 mg/kg bw/day
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 182 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 10
- DNEL extrapolated from long term DNEL
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 1 820 mg/kg bw/day
General Population - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- high hazard (no threshold derived)
Additional information - General Population
Potassium oxide/ Dipotassium oxide
General population
Humans differ in sensitivity due to a number of biological factors (such as age, gender, genetic composition and nutritional status). The intraspecies variation in humans is greater than in the more homogeneous experimental animal population
The data from animal studies are the starting point for risk characterisation.The default assumption in general is that humans are more sensitive than experimental animals.The traditional default AF (Assessment factor) suggested for interspecies extrapolation is 5 for workers and 10 for general population should be applied to the concentration/dose descriptor.
A lower default factor is generally suggested for the worker population, because the very young and very old are not part of this population.
To cover the intra-species variation, the default AF (Assessment factor) of 10 for general population was applied to the concentration/dose descriptor (NOAEL or NOAEC).
The dose descriptor for dermal irritation/corrosion come from dermal repeated study. In this study, the dose is reported in the unit mg/kg of body weight/day. This needs to be modified to enable comparison with the human exposure, generally expressed in mg/cm2/day.
We have taken that:
• the average weight of rats is 250g (200-300g), and the average weight of rabbit is 2.5 kg used by Merkel, D.J., N. 2000.
• the dose is applied over an area which is approximately 10% of the total body surface, and
• the total body surface of rats is on the average 445 cm2 (363 to 527 cm2) used by Merkel, D.J., N. 2000..
The generic modification from the NOAELtest (in mg/kg of body weight) to NOAELmodified (in mg/cm2/day) will be
NOAELin mg/cm2 = ((dose in mg/kg bw)x (average animal weight in kg)) / Treated surface in cm2)
NOAELtest* 0.25/44.5= NOAELmodified
The highest dose not causing irritation/corrosion was 1000 mg/kg bw in dermal toxicity study in rats of Merkel, D.J., N. 2000.
the modified dose descriptor would be
NOAELmodified =1000 mg/kg*0.25 kg/44.5cm2=5.62 mg/cm2
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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