Pesticides

Approximately 600 pesticides (as broadly defined to include herbicides as well as fungicides and insecticides) are applied in agriculture, silviculture and horticulture. On their passage through the sub-surface environment, these 600 active ingredients are transformed into an (unknown) number of degradable products (residues). The effects of active ingredients and their residues on non-target terrestial organisms (side effects), their fate in the soil and their undesired effects in groundwater are far from known with certainty for every substance. Only a few pesticide measurements in groundwater are available for a restricted number of constituents. Out of approximately 600 pesticides, only about 30 have been monitored. These 30 pesticides are neither the most mobile, nor representative of all pesticides.