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Partition coefficient

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Description of key information

Log D = -2.37 to 2.33 (pH 7) (QSAR Calculation, Marvin Sketch)

Key value for chemical safety assessment

Log Kow (Log Pow):
at the temperature of:
20 °C

Additional information

The experimental determination of the log Pow and the log Dow are not experimentally feasible because DOPA-Glycinate is a mixture and a surfactant.

Log Pow values for the 20 “major components” range from 0.33 to 6.71. The weighted Log Pow value = 3.82 (EpiSuite-KOWWIN). Log Pow values for the 24 chemical species making up the active substance ranged from 2.83 – 5.73 (QSAR Calculation using Marvin Sketch – ChemAxon, 2012).

However, the Log Pow QSAR calculations do not take into account that the 24 chemical species are ionisable species at environmental pH. Log Pow QSAR calculations are only appropriate for neutral molecules.

Log Dow is a more applicable endpoint for risk assessment. Log Dow is pH dependent and is applicable to protonated and unprotonated species.

The log Dow ranges for the 24 chemical species are provided below:

pH 5: log D = -4.53 to 2.11

pH 7: log D = -2.37 to 2.33

pH 9: log D = -3.12 to 3.92