Problem Of Pesticide Drift Studied
March 20, 2012 by UPI - United Press International, Inc.
WEST LAFAYETTE, Ind. (UPI) — Chemicals that help sprayed agricultural pesticides stick to crops can form smaller “satellite” droplets that can drift into other areas, U.S. scientists say.
“When we spray liquids, we have what we call main drops, which are drops of the desired size, and we can also have smaller satellite drops,” Purdue University professor of food science Carlos Corvalan said. “The smaller drops move easily by wind and travel long distances.”
Drifting of agricultural pesticides not only increases waste and cost for farmers, but also can cause health, environmental and property damage, the U.S. Environmental Protection Agency says.
Pesticides often contain chemical additives such as surfactants and polymeric additives, which help pesticides flow more easily and adhere to plant surfaces.
“Each additive is designed to improve the characteristics of the main drops,” Corvalan said. “But there is a side effect.”
The researchers found the additives can affect each other and lead to the smaller, drifting droplets.
Carefully controlling the strength and concentrations of the additives can mitigate or eliminate the formation of unwanted satellite droplets.
“Now that we know better how additives influence the formation of satellite droplets, we can control their formation,” Corvalan said.