Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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.
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: 201-607-5 | CAS number: 85-44-9
Partition coefficient
Administrative data
Link to relevant study record(s)
- Endpoint:
- partition coefficient
- Type of information:
- (Q)SAR
- Adequacy of study:
- key study
- Study period:
- 2017
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification
- Justification for type of information:
- QSAR calculation: detailed information see "any other information on materials and methods" and "any other information on results"
- Guideline:
- other: REACH guidance QSARs R6, May/July 2008
- Principles of method if other than guideline:
- Estimation Program Interface EPI-Suite version 4.11: KOWWIN (v1.68) for estimating the logarithmic octanol-water partition coefficient (log Kow).
The Estimation Programs Interface was developed by the US Environmental Agency's Office of Pollution Prevention and Toxics and Syracuse Research Corporation (SRC).© 2000 - 2012 U.S. Environmental Protection Agency for EPI SuiteTM (Published online in November 2012). - GLP compliance:
- no
- Type of method:
- other: QSAR
- Partition coefficient type:
- octanol-water
- Type:
- log Pow
- Partition coefficient:
- 2.07
- Temp.:
- 25 °C
- Remarks on result:
- not measured/tested
- Remarks:
- Calculation is pH independent
- Conclusions:
- The QSAR determination of the logarithmic octanol-water partition coefficient for phthalic anhydride using the model KOWWIN included in the Estimation Program Interface (EPI) Suite v4.11 revealed a logarithmic value of 2.07 of the substance. The predicted value can be considered reliable yielding a useful result for further assessment.
- Executive summary:
The logarithmic octanol-water partition coefficient (log Kow) for phthalic anhydride was predicted using the QSAR calculation of the Estimation Program Interface (EPI) Suite v 4.11. The log Kow was estimated to be 2.07 (Heilkenbrinker, 2017). The predicted value can be considered reliable yielding a useful result for further assessment.
- Endpoint:
- partition coefficient
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- data from handbook or collection of data
- Principles of method if other than guideline:
- measured
- GLP compliance:
- no
- Type of method:
- other: measured
- Partition coefficient type:
- octanol-water
- Type:
- log Pow
- Partition coefficient:
- 1.6
- Executive summary:
The log Pow of phthalic anhydride is 1.60 (Hansch, 1995).
Referenceopen allclose all
Validity of model:
1. Defined Endpoint:Octanol-water partition coefficient
2. Unambiguous algorithm:The molecule is separated into distinct atom/fragments using an Atom/Fragment Contribution method. Based on structure of the molecule, the following fragments were applied: aromatic carbon, ester-aromatic attach and a correction factor for the cyclic ester [di-carbonyl type] is applied.The number of times of the fragments that occurs in the structure of the substance applied by the program is verified.
3. Applicability domain:With a molecular weight of 148.12 g/mol g/mole the substance is within the range of the training set (18.02 - 719.92) as well as in the range of the validation set (27.03 - 991.15).
4. Statistical characteristics:Correlation coefficient of the total training set r² = 0.982; Correlation coefficient of the total validation set r² = 0.943.
5. Mechanistic interpretation:The structural fragments used as descriptors reflect the lipophilic or hydrophobic properties of the substances, and so the octanol-water partition coefficient.
6. Adequacy of prediction:The result for phthalic anhydride falls within the applicability domain described above and the estimation rules applied for the substance appears appropriate. Therefore the predicted value can be considered reliable yielding a useful result for further assessment.
pH and temperature not reported
Description of key information
The calculated log Kow of phthalic anhydride is 2.07 at 25 °C (Heilkenbrinker, 2017).
Key value for chemical safety assessment
- Log Kow (Log Pow):
- 2.07
- at the temperature of:
- 20 °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.
