Pesticides A Toxic Time Bomb in Our Midst

(Dana P.) #1

prohibited the setting of a tolerance. This had paradoxical effects in terms of food
safety, since alternative pesticides could pose higher (non-cancer) risks, and the EPA
allowed the same pesticide in other foods based on a determination that the risk was
negligible. The Delaney Clause still applies to food additives, but under the FQPA
pesticide residues are not considered food additives. Pesticide tolerances must be set
to ensure reasonable certainty of no harm.^61


Aggregate Exposure


Traditionally, the EPA has assessed human exposure to pesticides by individual
chemicals and a single route of exposure. For instance, a person may be exposed to a
pesticide through drinking water, eating food, and walking barefoot through recently
sprayed grass. The EPA would examine each exposure route separately and report the
risk separately, not combined. Under FQPA the EPA must consider all routes of ex-
posure when setting food tolerances. To help visualize this concept, the term ‘‘risk
cup’’ was coined to provide an analogy of total or aggregate pesticide exposure.
Returning to the previous example, before FQPA there would have been three risk
cups for each pesticide exposure through drinking water, eating food, and walking
barefoot through recently sprayed grass. After FQPA, the EPA has only one risk cup
that must account for all exposures to pesticides through water, food, and walking
barefoot through recently sprayed grass. The risk cup is only so big and will allow
only a finite amount of risk in the cup. When the risk cup becomes full, then any
excess risk or exposure must be controlled. The size of the cup is determined by the
definition of reasonable certainty of no harm. The EPA has developed an interim
approach that assigns portions of the risk cup to specific pesticide exposure pathways.
The risk cup is divided into 5 percent for residential exposure, 5 percent for outdoor
exposure, 10 percent for drinking water exposure, and 80 percent for food exposure.
These are the assumptions that will guide the EPA’s tolerance setting decision-making
process until other methods have been researched and developed.^62


Additional Tenfold Safety Factor for Children


Prior to the passage of the FQPA, the EPA tolerance-setting process did not
account for the special diet considerations of infants and children. Infants and chil-
dren have different food consumption patterns and may detoxify pesticides they are
exposed to differently. A National Academy of Science report recommended up to a
tenfold safety factor be used in setting the tolerance for food to account for the spe-
cial needs of children. For example: the current tolerance for a pesticide on apples is
100 parts per million (ppm). With the addition of a tenfold safety factor for children,
the tolerance would now be set at 10 parts per million. The EPA has determined that
there will not be an across-the-board tenfold safety factor added to every tolerance.
The EPA will assess each tolerance and apply up to a tenfold safety factor on a case-
by-case basis.^63


The Pesticide Problem | 19
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