Agriculture Reference
In-Depth Information
c.
Pesticide Factors
Some pesticide chemicals are more likely than others to move to ground
water. Such movement depends mainly on:
•
solubility
—Some pesticides dissolve easily in water and are more
likely to move into water systems
Figure 9.5
Movement of rainwater and irrigation water on treated surfaces
(EPA, Applying Pesticides Correctly, 1991).
•
adsorption
—some pesticides become tightly attached (strongly ad-
sorbed) to soil particles and are not likely to move out of the soil and
into water systems
•
persistence
—some pesticides break down slowly and remain in the
environment for a long time
These factors are all related to one another. Pesticides that are most likely
to move into groundwater are highly soluble, moderately to highly persistent,
and are not strongly adsorbed to soil. A nonpersistent pesticide would be less
likely to move to groundwater, even if it is highly soluble or not strongly
