When a pesticide goes into solution with water, the pesticide will move where the water goes. These are equivalent. It tells the maximum number of milligrams that will dissolve in one liter of water. Simply being water soluble does not mean that a pesticide will leach into ground water or run off into surface water. However, solubility does mean that if a soluble pesticide somehow gets into water, it will probably stay there and go where the water goes.
Water solubility is one indicator of the pesticides mobility in water.
However, like most rules, there are exceptions. Pesticides with solubilities of 1 ppm or less are believed to have a higher likelihood of runoff. Likewise, pesticides with high K oc values are more likely to run off than leach. Nonpoint sources are broad, undefined areas in which pesticide residues are present. Figure 3 .