Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 204-385-8 | CAS number: 120-32-1
- 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
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:
- 16 Nov 2001 to 4 Oct 2002
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- comparable to guideline study
- Qualifier:
- according to guideline
- Guideline:
- other: Draft OECD Guideline 122 (Partition Coefficient (n-octanol/water), pH-Metric Method for Ionizable Substances
- Version / remarks:
- November 2000
- Deviations:
- yes
- Remarks:
- pH range used was 3 to 12, instead of 2 to 12.
- GLP compliance:
- not specified
- Type of method:
- other: pH-metric titration
- Partition coefficient type:
- octanol-water
- Key result
- Type:
- log Pow
- Partition coefficient:
- 4.276
- Temp.:
- 25 °C
- Remarks on result:
- other: Log Pow of un-ionised species.
Reference
Conclusion
The calculated dissociation constant (pKa) at zero-percent organic content was 9.59.
The partition coefficient (log Pow) of the un-ionised species was evaluated by pH- metric titration to be 4.276 at nominally 25°C.
Discussion
The lipophilicity profile demonstrates that the log D changed little over the environmentally significant pH range of pH 4 to pH 9 (see table of Log D at Specific pH, below). In the pH region where the test substance is fully un-ionised, log D is equivalent to log P, and the substance is maximally partitioning in the organic phase. Above pH 9, (pKa value of 9.59), the test substance becomes ionised. This in turn causes its redistribution between the two phases, with more substance shifting to the aqueous phase and the log D value falls to ca 2 at pH 12. The Distribution of the Species plot indicates that in acidic to neutral conditions (pH 2 to 7) the test substance is un-ionised and will partition in the organic phase. As the conditions become basic (pH 8 to 12) the presence of un-ionised test substance reduces with the dominating species of ionised test substance tending to partition in the organic phase.
Indvidual Raw Results
pKa Value
Titration data sets of pH against volume of titrant were manipulated electronically using pKaLOGP v5.1. Six apparent pKa values in the presence of co-solvent were evaluated. Using the same software a “Multi-set” of the six data sets was formed and a Yasuda-Shedlovsky extrapolation performed to calculate the pKa value at zero percent organic content. Two of the six points were excluded from the Yasuda- Shedlovsky plot due to their poor fit with the line.The pKa was evaluated to be 9.59.
Apparent pKa values are presented in Table below.
Methanol Content (% w/v) |
Apparent pKa |
49.75 |
10.415 |
42.30 |
10.351 |
31.99 |
10.038 |
57.14 |
10.551 |
46.73 |
10.425 |
36.84 |
10.143 |
Log P Value
Titration data sets of pH against volume of titrant were manipulated electronically using pKaLOGP v5.1 software. Initially the multi-titration containing runs 1, 2 and 3 were performed. Only the first titration containing 0.1 mL of octanol gave a refineable result. Three further individual titrations using 0.2, 0.5 and 0.3 mL of octanol respectively were then performed. The higher volumes of octanol caused problems during the titration, and only those with octanol volumes of 0.1 and 0.2 mL gave refinable results. These two data sets were combined to form a “multi-set” to give a set of averaged results.
The calculated log P of the un-ionised species was determined as 4.276, with a goodness of fit (GOF) of data of 2.53.
The table below shows the log D value at a specific pH over the environmentally significant pH range of 4 to 9.
Table of Log D at Specific pH:
pH |
4 |
5 |
6 |
7 |
8 |
9 |
log D |
4.276 |
4.276 |
4.276 |
4.275 |
4.265 |
4.175 |
Description of key information
Log Kow is 4.276 at 25 ºC (OECD 122, pH-metric titration in the presence of octanol).
Key value for chemical safety assessment
- Log Kow (Log Pow):
- 4.276
- at the temperature of:
- 25 °C
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.