Analysis of Organic Pesticides by
Chromatography
DONALD S. MAY, JR., Sanitary Chemist
ERVIN HINDIN, Associate Sanitary Chemist
GILBERT H. DUNSTAN, Head
Sanitary Engineering Section
Division of Industrial Research
Washington State University
Pullman, Washington
PESTICIDES AND WATER POLLUTION
The increasing use of synthetic organic chemicals for the control of pests on
croplands, forests, and marshes poses a potential pollution problem to our nation's
water courses. More and more cultivated land in the United States is being treated
with synthetic organic insecticides and herbicides each year. Runoff waters from
these treated areas inevitably pick up minute quantities of pesticide material. In
addition these compounds may enter water supplies through applications to water
surfaces or by uncontrolled drifting onto water when nearby areas are treated. In
view of these circumstances, federal and state health agencies are seriously concerned about the quantities of toxic compounds present in our water supplies.
The U. S. Public Health Service has, on occasion, found pesticides in concentrations ranging from one to 20 ppb in the Mississippi, Missouri, and Columbia
Rivers (1). Aldrin was found at a concentration of one ppb in the Snake River near
Lewiston, Idaho (2). Although the toxic properties of minute quantities of pesticides to humans are not fully understood, their effects on fish and wildlife have
been documented (3,4,5).
The widespread use and great stability of most of the chlorinated hydrocarbons
in the environment and the fact that they are readily accumulated and stored in or
on animal and plant tissues compound their hazard to wildlife. In addition to
lethal effects resulting from either direct exposure to or accumulation of these
toxicants, effects on the physiology of animals such as the suppression of reproduction has resulted from repeated exposure to sublethal amounts. Several studies
revealed adverse effects to wildlife occurred after application of insecticides at or
below recognized safe levels. Residue levels of chlorinated hydrocarbons accumulated in Tish and wildlife often have been found to exceed tolerances established
for man's foods and may have public health implications (4).
Discharge of pesticide water by certain industries has resulted in extensive
local fish kills and is suspected of affecting fish over many miles of stream. Par-
athion, which has been generally considered to decompose rapidly, was found as a
contaminant of farm ponds nine months after application to surrounding orchard
soil (5).
A particular Southeastern community used water from a stream which drained
a cotton-growing area. Nearly continuous water sampling for organic material
was carried on by the city's municipal water plant. Recovered concentrations of
the particular pesticides used on the fields ranged from less than five to 150 parts
per trillion with largest recoveries occurring during and just after the late summer
period of intensive pesticide application (5).
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