ABSTRACT
A series of microcosm experiments was set up to study the potential for herbicide degradation in groundwater samples collected from unconfined chalk, limestone and sandstone aquifers in the UK. The microcosms were incubated at 20°C under aerobic conditions and spiked with either isoproturon, or atrazine at a concentration of 100 µg/L. Under these conditions isoproturon could be degraded in groundwater samples from each of the major aquifer types. Biodegradation was associated with the formation of mono and didesmethyl-isoproturon. The most consistent and rapid isoproturon degradation was associated with sandstone groundwater and the slowest with Limestone. A very small amount of atrazine degradation was observed over 300 d incubation.
