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When released into terrestrial environments, volatilization of ETU from moist soil surfaces is not expected to be an important fate process given an estimated Henry's Law constant of 3.4X10-7 atm-cu m/mole, using a fragment constant estimation method. It is not readily biodegradable under aerobic conditions (0 % of biodegradation after 28 days) and is not expected to sorb significantly to soil and sediment (based upon its low log Kow value (-0.67)).Indeed, based on the fact that the substance is characterized by a low potential of adsorption, no simulation test is proposed for the soil and sediment compartments.Because of its moderate sorption affinity, ETU is expected to be mobile in soil. As a consequence, the soil and sediment compartments are not considered as the main target compartments of ETU.Last but not least, the risk assessment showed that there was no risk due to soil exposure.

A dateline on the mineralisation of organic N by soil microorganism is available in a review. However, no NOEC was mentioned. Graphically, we can estimate it to be probably between 0.1 and 10 mg/kg soil. It is not clear whether the results were expressed in kg wet soil or dry soil. The exact NOEC is also unclear as the experimental design and statistics were not presented. Therefore, this result cannot be used to derive a PNEC.