Organoclay-based formulations to reduce the environmental impact caused by herbicides commonly applied to olive groves

Abstract

Ground and surface water contamination by herbicides commonly applied to olive groves is a matter of current concern in Mediterranean regions. The fact that most commercial herbicide formulations in cur­rent use contain the herbicide in an immedi­ately available form that is readily released into the environment exacerbates the risk of ground and surface water contamination by rapid herbicide transport losses. In this work, we prepared slow release formula­tions of three herbicides (diuron, terbuthy­lazine, and MCPA) widely applied to olive groves by preadsorbing the herbicides on hexadecyltrimethylammonium-modified montmorillonite. Then, we evaluated the ability of the organoclay-based formulations to slow the release of the herbicides into wa­ter and to reduce their leaching through soil columns, as compared to conventional commercial formulations containing the herbicides in a readily available form. The results indicated that organoclay-based for­mulations can be useful to reduce the mobil­ity of the assayed herbicides after applica­tion to soils such as those typically used for olive growing in Mediterranean regions.