Isoproturon mainly enters the environment during its application as an agricultural herbicide, but releases may also occur during manufacture, transportation and storage.  Isoproturon has a low tendency to adsorb to soils and is therefore quite able to enter in water bodies although it has a rather low water solubility of 70.2 mg/l. In water; it takes about 30 days to half its concentration, while it takes about 40 days in soils. 
Due to its low affinity for organic matter it is not expected to have a high tendency towards bioaccumulation or biomagnification. Significant bioaccumulation might however occur in certain species. 
Isoproturon is shown to be very toxic for oysters which can die at concentrations above 370 µg/l. Algae are also very vulnerable and can start dying at concentrations above 13 µg/l. Long term exposure to concentrations above 1 mg/l might affect the growth of fishes, although they only start dying at concentrations above 18 mg/l. In fresh water concentrations of 0,125 µg/l have been recorded.
- WHO 2003 chemical fact sheet
- www.environment-agency.gov.uk August 18 2009
- WHO 2003 Background document for development of WHO Guidelines for Drinking-water Quality
- MERLIN Gerard, VUILLOD Maryline, LISSOLO Thierry, CLEMENT Bernard 2002 Fate and bioaccumulation of isoproturon in outdoor aquatic microcosms; Environmental toxicology and chemistry
- Review report for the active substance isoproturon, adopted December 7 2001