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Tetrakis(hydroxymethyl)phosphonium chloride, oligomeric reaction product with urea (called "THPC-urea" in the following text) is not stable to hydrolysis. Two peaks are determined during the hydrolysis test but the kinetic is variable and therefore half lives could only be determined for one of the two peaks (from 3 hours at pH 4 to 10 days at pH 9 at 25°C). Besides the degradation products could not be determined. Then a half life of 3 days at 25°C is considered in the risk assessment.

The substance is not found to be readily biodegradable. A maximum of 11% biodegradation was obtained in a readily biodegradation test and 29% in an inherent biodegradation test. The substance seems to have some potential to biodegrade however it is toxic to microorganisms. Therefore in all biodegradation tests performed an inhibitory effect of the substance to microorganisms is one of the explanations for the lack of biodegradation.

With a low Log Pow value (-1.15), THPC-urea is not expected to have bioaccumulation potential.

Finally the substance does not have a high potential for adsorption and could therefore be considered as mobile. However this is difficult to estimate due to the complexity of the substance.