Isoproturon 50% / 75% WP

Isoproturon is non-persistent in soil; very photochemically stable, and stable to acids and alkalis,^[1] but under sustained ultraviolet light can degrade into some eleven products,^[5] and can be hydrolytically cleaved by strong bases on heating.^[1]

Degradation is mainly N-demethylation and oxidation of the ring-isopropyl group. Variations in order give rise to a few possible pathways, and the balance of demethylation and oxidation can allow selective activity of the herbicide. Both reactions may occur, making a typical degradation product of 2-(4-Aminophenyl)propan-2-ol (also called Dimethyl-p-Aminobenzylalkohol),^[5] which is an irritant and may be harmful if swallowed.^[18]

Most isoproturon is expected to have degraded in soil after 6-28 days; the rate is temperature sensitive as the process is driven by enzymes and microbes.^[1] In water, the DT₅₀ is 40 days, and in water sediments 149 days.^[7]

Metabolism in plants usually follows the path beginning with isopropyl side chain oxidation.^[5] White-rot fungus has the lignin-degrading enzymes lignin peroxidase and manganese peroxidase which are known to degrade