Isoproturon (IPU) is a urea class selective herbicide, which has been used to control annual grasses and many broad leafed weeds in wheat, barley, rye and triticale.

[1] It was once one of the most widely used herbicides in the world, however it has suffered various bans, including the USA, and until 2016 was sold in 22 European countries.

[13] Isoproturon's registration in the European Union is expired, though under EC Regulation 1107/2009 it is approved in the Netherlands and no other EU member nation.

[14] The European Court of Justice ruled in December 2015 that the commission illegally broke their "clear, precise and unconditional obligation" to publish scientific criteria.

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.

[16] 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.

[5] Technical grade isoproturon is >97% pure, and is then sold as an active ingredient in commercial formulations, usually as an SC, suspended concentrate, or WP, wettable powder.

Isoproturon is used on crops such as wheat, rye, barley, triticale,[1] sugarcane, citrus, cotton, asparagus,[9] oilseed rape, peas, spring field beans, sugar beet, potatoes, carrots, brassicas and onions.