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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 202-653-9 | CAS number: 98-29-3
- 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
![](https://chesar.echa.europa.eu/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/print_physical-and-chemical-properties.png)
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:
- report date: 2010-02-18
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: The study was conducted according to recognised guidelines.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EU Method A.8 (Partition Coefficient)
- Deviations:
- no
- GLP compliance:
- no
- Type of method:
- flask method
- Partition coefficient type:
- octanol-water
- Analytical method:
- high-performance liquid chromatography
- Key result
- Type:
- Pow
- Partition coefficient:
- 103.66
- Temp.:
- 25 °C
- pH:
- 5.9
- Key result
- Type:
- log Pow
- Partition coefficient:
- 1.98
- Temp.:
- 25 °C
- pH:
- 5.9
- Details on results:
- MEASUREMENT AND CALCULATION:
The partition coefficient (Pow) is defined as the ratio of the equilibrium concentrations of a dissolved substance in a two-phase n-octanol and water:
Pow = Cn-octanol / Cwater
Where Cn-octanol and Cwater are respectively the solute’s concentrations (mol/L) in the n-octanol and water phases.
Cn-octanol and Cwater are calculated with the calibration equation between peak area and 4-TBC concentration. The peak area represents the response of 4-TBC to the DAD at 280 nm during the chromatographic separation.
The experimental method leads to the following results for the three different volumic ratios (see Table 2). The standard deviation is calculated on the three analyses for each phase and each assay.
The pH of water before measurement is 6.8. - Conclusions:
- The average n-octanol/water partition coefficient (Pow) of 4-tert-butylpyrocatechol (4-TBC) is 103.66 +/- 43.12.
The decimal logarithm of n-octanol/water partition coefficient (Log Pow) is 1.98 +/- 0.20 (standard deviation). - Executive summary:
In a study (Processium, 2010), the partition coefficient was determined by HPLC method and using the shake flask method, according to the regulation (EC) n°440/2008, A.8 and the OECD Guideline n°107.
The average n-octanol/water partition coefficient (Pow) of 4-tert-butylpyrocatechol (4-TBC) is 103.66 +/- 43.12.
The decimal logarithm of n-octanol/water partition coefficient (Log Pow) is 1.98 +/- 0.20 (standard deviation).
This study is classified as acceptable and satisfies the guideline requirements for a partition coefficient study.
Reference
Table 2: Analytical results of 4-TBC in water and octanol for determination of Pow
Sample |
Volumic ratio of water phase and octanol phase (Vwater / Voctanol) |
Concentration in water phase (mg/L) ±standard deviation |
Concentration in octanol phase (mg/L) ±standard deviation |
pH in water phase |
Pow |
Log Pow |
Assay 1 |
0.51 |
7.10±1.63 |
1084.6±11.1 |
5.9 |
152.76 |
2.18 |
Assay 2 |
1.00 |
11.45±3.04 |
1091.4±2.5 |
5.9 |
95.32 |
1.98 |
Assay 3 |
1.99 |
18.75±1.06 |
1072±11.9 |
5.9 |
57.17 |
1.76 |
Assay 4 |
0.50 |
10.05±1.77 |
1145.4±24.4 |
5.9 |
113.97 |
2.06 |
Assay 5 |
1.00 |
7.45±4.17 |
1109.9±52.1 |
5.9 |
148.98 |
2.17 |
Assay 6 |
2.01 |
20.5±3.08 |
1101.5±21.3 |
5.9 |
53.73 |
1.73 |
Description of key information
Partition coefficient: 1.98
Key value for chemical safety assessment
- Log Kow (Log Pow):
- 1.98
- at the temperature of:
- 25 °C
Additional information
One experimental study (Processium, 2010) with reliability 1 according to Klimisch was available and was selected as key study. Partition coefficient was determined by HPLC method and using the shake flask method, according to the regulation (EC) n°440/2008, A.8.
Data coming from peer-review handbooks were available. As the values are in the same range, they are used in a supporting approach.
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.
![ECHA](/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/echa_logo.png)