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Environmental fate & pathways

Phototransformation in air

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Description of key information

Model calculation using EpiSuite 4.10 (AOP program v1.92, US-EPA, 2008):
Half-life for reaction with hydroxyl radicals ( 0.5E6 OH/cm³) = 16.97 h
Half-life for reaction with ozone (at 7E11 mol/cm³) = 24.2 h
Combined calculation result = 10 h

Key value for chemical safety assessment

Half-life in air:
16.97 h

Additional information

The methacrylate esters do not possess UV-absorbing structures. Therefore, direct photolysis is not expected to occur to any significant degree.

Photodegradation in the atmosphere is expected to occur either by reaction with photo-chemically produced hydroxyl radicals or by reaction with ozone. For reaction with ozone an atmospheric half-life of approximately one day has been calculated for i-BMAusing EpiWin v4.10 AOP v1.92 and for the reaction with hydroxyl radicals a half life of 16.97 h was estimated.

In conclusion, after evaporation or emission to air, i-butyl methacrylate will be rapidly degraded by photochemical processes.