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Environmental fate & pathways

Adsorption / desorption

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Description of key information

Adsorption to the solid soil phase is not expected.

Key value for chemical safety assessment

Koc at 20 °C:

Additional information

A calculated log Koc of 1.79 is available (BASF SE, SRC PCKOC v2.0, 2011). This value refers to the uncharged molecule (pKa value: 5.75). The pKa value indicates that the molecule will exist partly as an anion in the environment. Hence, the PCKOC-model may misestimate adsorption to organic carbon since it does not consider the ionic structure of the molecule. Under environmental conditions (pH from 5 to 9) the test substance is partly present in its charged form (as calculated by the formula % ionised = 100/(1+10(pKa - pH)). In a calculation conducted according to a publication by Franco & Trapp, 2008 using the parameters pKa = 5.75 and log Pow = 0.54 a log Koc range of 1.9 at pH 9 and 2.94 at pH 5 was determined. For further assessment the corrected worst case logKoc at pH 5 is used.