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EC number: 200-101-1 | CAS number: 51-48-9
- 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
Partition coefficient
Administrative data
Link to relevant study record(s)
- Endpoint:
- partition coefficient
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2019
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)
- Qualifier:
- according to guideline
- Guideline:
- EU Method A.8 (Partition Coefficient - HPLC Method)
- Qualifier:
- according to guideline
- Guideline:
- EPA OPPTS 830.7570 (Partition Coefficient, n-octanol / H2O, Estimation by Liquid Chromatography)
- GLP compliance:
- yes (incl. QA statement)
- Type of method:
- HPLC method
- Partition coefficient type:
- octanol-water
- Specific details on test material used for the study:
- Name: LEVOTHYROXINE ACID
Batch No.: B486066
Expiry date: 27 August 2020
Storage condition: at room temperature, protected from light
Appearance: white slightly creme, powder - Analytical method:
- high-performance liquid chromatography
- Key result
- Type:
- log Pow
- Partition coefficient:
- >= 2.727 - <= 2.733
- Temp.:
- 25 °C
- pH:
- ca. 6.5
- Conclusions:
- In the course of this study the partition coefficient (Pow) of Levothyroxine Acid was determined using high performance liquid chromatography.
The determined log Pow: 2.73 ± 0.003 (95 % confidence interval).
The estimated Pow: 533 ± 3.4 (95 % confidence interval). - Executive summary:
The partition coefficient Pow was determined based on a calibration curve using seven reference items.
The capacity factors (k) were calculated from the dead time and retention times of the reference substances. The log k data of the reference substances were plotted against their log Pow values. The equation of the curve fitted to the calibration points is as follows:
log k = 0.411 * log Pow - 0.810 (Rsq = 0.990)
- Endpoint:
- partition coefficient
- Type of information:
- (Q)SAR
- Adequacy of study:
- supporting study
- Study period:
- 2021
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- results derived from a (Q)SAR model, with limited documentation / justification, but validity of model and reliability of prediction considered adequate based on a generally acknowledged source
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- The partition coefficient log Pow of the test substance was estimated by an Atom/Fragment Contribution Method using the software KOWWIN Version v1.68, contained in the EPI Suite v4.1 programme of the U.S. Environmental Protection Agency.
- GLP compliance:
- no
- Type of method:
- other: calculation
- Partition coefficient type:
- octanol-water
- Specific details on test material used for the study:
- SMILES used : COc1ccc(cc1)Oc2c(cc(cc2I)CC(C(=O)O)N)I
- Key result
- Type:
- log Pow
- Partition coefficient:
- ca. 4.12
- Conclusions:
- Log Kow (KOWWIN v1.68 estimate) = 4.12
- Executive summary:
Log Octanol-Water Partition Coef (SRC):
Log Kow (KOWWIN v1.68 estimate) = 4.12
Referenceopen allclose all
Description of key information
The partition coefficient was determined from the solubilities in water in n-octanol.
In the course of this study the partition coefficient (Pow) of Levothyronine acid was determined using high performance liquid chromatography.
The determined log Pow is 2.73 ± 0.003 (95 % confidence interval).
The estimated Pow is 533 ± 3.4 (95 % confidence interval).
The log Pow is 4.12, when estimated by QSAR.
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.