Chemical pesticides have a wide sphere of influence and thus must be used with
caution and concern for the entire influenced zone. Obviously the rule must be to use
the least toxic agent and the minimum quantity for the particular job. Consideration
should be given to the most sensitive stage of the pest’s development in order to
permit this rule to be most effective. In addition, the state of the application
equipment and weather conditions must be given consideration before commencing
operation.
Although a discrete area may be slated for a spraying or other poisoning operation, the nature of the soil, rainfall, and presence of migratory animals, all contribute
to the size of the zone of influence.
9.2 Fate and Transport of Pesticides in the Environment
The effect of pesticide use on the environment is of great concern because of
possible unintended consequences. These can include impacts on water supply and
soil contamination as well as producing injury or death to nontarget species.
Certain pesticides will have more acute and direct lethal and sublethal effects,
while others will have indirect habitat damage and destruction, which has longerterm implications on, for example, fish and aquatic invertebrate survival rates.
A variety of factors control the distribution of chemical pesticides on land, air,
and water that are both chemically specific, as well as, dependent on the local
environmental conditions. Characteristics of individual chemical compounds such
as water solubility, vapor pressure, lipophilic nature or octanol-water partition
coefficient, and half-life or chemical persistence are important factors to consider
when modeling fate and transport. Local environmental conditions such as air and
water temperature, rainfall, sun exposure (photodegradation), and redox condition
add a dynamic element with both temporal and spatial variability that needs to be
considered to fully predict distribution of pesticides in nature. For example, when
applying pesticides in and around a warehouse, judicious use of pesticides in the
immediate footprint of existing structures and new construction minimizes the
potential for run-off that may contain contaminated soils.
For example, neonicotinoid insecticides are very water soluble, which allows
them to be applied to soil and taken up by plants. This also makes aquatic ecosystems and associated organisms particularly vulnerable to this class of pesticides.
Linkages of neonicotinoid exposure to unintended consequences of honey bee
pollinator Colony Collapse Disorder (CCD) have also been observed.
9.3 Biological Magnification
It must also be recognized that immediate influence does not tell the whole story,
since biological magnification can eliminate organisms that were not influenced by
the initial contact with the agent. Thus, acceptable water concentrations of pesticides
10 Environmental Control of Pests and Vectors
407
caution and concern for the entire influenced zone. Obviously the rule must be to use
the least toxic agent and the minimum quantity for the particular job. Consideration
should be given to the most sensitive stage of the pest’s development in order to
permit this rule to be most effective. In addition, the state of the application
equipment and weather conditions must be given consideration before commencing
operation.
Although a discrete area may be slated for a spraying or other poisoning operation, the nature of the soil, rainfall, and presence of migratory animals, all contribute
to the size of the zone of influence.
9.2 Fate and Transport of Pesticides in the Environment
The effect of pesticide use on the environment is of great concern because of
possible unintended consequences. These can include impacts on water supply and
soil contamination as well as producing injury or death to nontarget species.
Certain pesticides will have more acute and direct lethal and sublethal effects,
while others will have indirect habitat damage and destruction, which has longerterm implications on, for example, fish and aquatic invertebrate survival rates.
A variety of factors control the distribution of chemical pesticides on land, air,
and water that are both chemically specific, as well as, dependent on the local
environmental conditions. Characteristics of individual chemical compounds such
as water solubility, vapor pressure, lipophilic nature or octanol-water partition
coefficient, and half-life or chemical persistence are important factors to consider
when modeling fate and transport. Local environmental conditions such as air and
water temperature, rainfall, sun exposure (photodegradation), and redox condition
add a dynamic element with both temporal and spatial variability that needs to be
considered to fully predict distribution of pesticides in nature. For example, when
applying pesticides in and around a warehouse, judicious use of pesticides in the
immediate footprint of existing structures and new construction minimizes the
potential for run-off that may contain contaminated soils.
For example, neonicotinoid insecticides are very water soluble, which allows
them to be applied to soil and taken up by plants. This also makes aquatic ecosystems and associated organisms particularly vulnerable to this class of pesticides.
Linkages of neonicotinoid exposure to unintended consequences of honey bee
pollinator Colony Collapse Disorder (CCD) have also been observed.
9.3 Biological Magnification
It must also be recognized that immediate influence does not tell the whole story,
since biological magnification can eliminate organisms that were not influenced by
the initial contact with the agent. Thus, acceptable water concentrations of pesticides
10 Environmental Control of Pests and Vectors
407