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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 272-574-2 | CAS number: 68890-66-4
Endpoint summary
Administrative data
Description of key information
BIOACCUMULATION IN WATER/SEDIMENT
Octopirox is a weak acid with a pKa of 5.9. This means the neutral form of Octopriox is deprotonated at high pH and is ionic. At pH4 most of the Octopirox exists in the neutral form whereas at pH 9 almost all Octopirox exists in the ionic form. Clariant has measured the n-Octanol solubility of Octopriox which is 37.5 g/L. The water solubility of Octopriox is pH dependant: pH4 22.1 mg/L, pH7 29.8 mg/L and pH9 473 mg/L. This results in a Log Coctanol/Cwater of 3.2 for pH4, 3.1 for pH7 and 1.9 for pH9. As expected the ionic form of Octopirox at pH 9 has the lowest partitioning coefficient. In order to confirm these estimates an OECD 107 Shake flask test was carried and the Log Kow was measured to be 3.86 at pH4 (neutral form: worst case). Based on the CLP Criteria for Bioaccumulation e.g. Log Kow >=4 or REACH PBT & vPvB B Screening criteria of Log Kow >4.5 these criteria for Octopirox are not fullfilled. The BCF and BAF for the neutral form of Octopirox can be estimated with the program US EPIWIN 4.2: BCF=131 L/kg and BAF=230 L/kg wet weight. These estimates support a low bioaccumulation potential of Octopirox. Therefore a Bioaccumulation study in water/sediment is not warranted. The statement given above fulfills the requirement for waiving as given in 1907/2006/EC Annex IX, Column 2, 9.3.2: The study need not be conducted if the substance has a low potential for bioaccumulation and /or a low potential to cross biological membranes.
BIOACCUMULATION IN SOIL
Octopirox is a weak acid with a pKa of 5.9. This means the neutral form of Octopriox is deprotonated at high pH forming an ionic form. At pH4 most of the Octopirox exists in the neutral form whereas at pH 9 almost all Octopirox exists in the ionic form. Clariant has measured the n-Octanol solubility of Octopriox which is 37.5 g/L. The water solubility of Octopriox is pH dependant: pH4 22.1 mg/L, pH7 29.8 mg/L and pH9 473 mg/L. This results in a Log Coctanol/Cwater of 3.2 for pH4, 3.1 for pH7 and 1.9 for pH9. As expected the ionic form of Octopirox at pH 9 has the lowest partitioning coefficient. In order to confirm these estimates an OECD 107 Shake flask test was carried and the Log Kow was measured to be 3.86 at pH4 (neutral form: worst case). No Bioaccumulation criteria for the soil compartment exist. But it is very likely that Octopirox has also in the terrestrial compartment a low bioaccumulation potential as in the aquatic compratment (see IUCLID Section 5.3.1). This is confirmed by the QSAR estimate for BCF worm of the neutral form of Octopirox calculated by EUSES Version 2.1 which is 96 L/kg ww.
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.
