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Environmental fate & pathways

Phototransformation in air

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Description of key information

Phototransformation in air is not a relevant degradation pathway.

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Additional information

No experimental data for the assessment of photodegradation of Y-15099 (CAS 220727-26-4) in air are available. The substance is hydrolytically unstable. Therefore, the half-life in air was calculated for the hydrolysis products as well. Based on an accepted estimation method using AOPWIN v1.92, the hydrolysis products are susceptible to indirect photodegradation in air (Müller, 2012). The estimated half-life for the reaction with OH-radicals is 10.185 h (24 h day; OH-concentration 0.5E+06 OH/cm³). This is also the case for the hydrolysis products with a calculated half-life of 7.067 – 107.669 h (24 h day; OH-concentration 0.5E+06 OH/cm³). However, this is not expected to be a relevant environmental fate process, since Y-15099 and its hydrolysis products are not expected to be present in the atmosphere based on the low calculated Henry's Law Constant of < 1 Pa m³/mole.

The hydrolysis product ethanol, which is expected to participate mainly to the atmospheric compartment is well characterized and the expected half-life was estimated to be 10 - 36 h. It's photochemical ozone creation potential is considered to be moderate to low (OECD, 2004).

References: OECD (2004): Ethanol. SIDS Initial Assessment Report For SIAM 19, Berlin, Germany, 19 - 22 October 2004. UNEP publications.