- Eight states collect information on the use of pesticides within their states, but
only two collect information on pesticides used in schools. No state collects infor-
mation on exposure patterns in schools. - There are no standard criteria for clearly identifying illnesses linked to pesticide
exposure; misclassification of pesticide illness is common.^45
Eliminating pesticides from the school environment is critical to lowering chil-
dren’s total exposure. Children spend an average of six to seven hours per day, five
days per week, 180 days per year, in school. The only other place where children
spend more time is in their homes. In order to protect children’s health wherever they
work and play, pesticide use in schools must be reduced, and families must be rou-
tinely notified whenever pesticides will be applied in schools.
As the public becomes more aware of the health and environmental risks pesticides
may pose, interest in seeking the use of equally effective alternative pest control meth-
ods increases. School administrators and others who have pest control decision-making
responsibilities for school buildings and grounds should become aware of the pest con-
trol options available to them. It is in everyone’s best interest to reduce exposure to
potentially harmful chemicals in the educational environment.
Pesticides and Water Quality
Pesticides not absorbed by plants and soils or broken down by sunlight, soil organ-
isms, or chemical reactions may ultimately reach groundwater sources of drinking
water. This depends on the nature of the soil, depth to groundwater, chemical prop-
erties of the pesticide, and the amount and timing of precipitation or irrigation in an
area. Usually, the faster a pesticide moves through the ground, as with sandy soils
and heavy rainfall or irrigation, the less filtration or breakdown. Heavier soils, com-
bined with lower moisture levels and warmer temperatures, provide a greater oppor-
tunity for pesticides to break down before reaching groundwater. The amount of a
pesticide detected in well samples also relates to the kind of pesticide and the amount
originally applied. Contamination problems can result from using high concentra-
tions of water-soluble pesticides for a specific crop in a vulnerable area.
Pesticides are, of course, designed to be toxic for certain insects, animals, plants, or
fungi. But when used without regard to site characteristics, such as adsorption
capacity of the soil (‘‘adhesion’’), solubility, climatic conditions, and irrigation pat-
terns, a given pesticide can create greater environmental problems than the damage
the target pest could cause. Once in groundwater, pesticides continue to break down,
but usually much slower than in surface layers of soil. Groundwater carrying pesti-
cides away from the original point of application can lead to contaminated well sam-
ples years later in a different location.
To avoid pesticide contamination, informed and careful pest control is necessary.
Overapplication is a possible cause of pesticides in water supplies. Consequently,
pesticides should not be viewed as the only answer to a pest problem; other methods
12 | Pesticides