Pesticide drift is the airborne movement of pesticides from an area of application to any unintended site. Drift can happen during pesticide application, when droplets or dust travel away from the target site. It can also happen after the application, when some chemicals become vapors that can move off-site. Pesticide drift can cause accidental exposure to people, animals, plants and property.
You might think of pesticide drift as the movement of spray droplets during application. This is called 'particle drift.' But, some pesticides are more likely to drift in the form of vapor. This can happen after an application even when the pesticide was applied as a solid or liquid. This is called 'vapor drift,' and an important factor is the pesticide's vapor pressure.
Pesticide drift can pose health risks to people and pets when sprays and dusts drift to nearby areas such as homes, schools, and playgrounds. Wildlife and plants are also at risk when drift affects natural areas and water sources. Herbicide drift can damage other nearby crops or make them unsellable if the active ingredient is not registered for a particular crop. Pesticide drift also results in wasted pesticide product. EPA estimates up to 70 million pounds of pesticides are lost to drift each year.
Reading the label is the first and most important way to minimize risk and exposure. Understanding the approved use instructions will help reduce the risk of drift. There are four main drift factors the EPA focuses on when reviewing pesticide product registrations:
To learn more, see the resources below or contact NPIC for assistance. If you have questions about drift, or any pesticide-related topic, please call NPIC at 1-800-858-7378 (8:00am - 12:00pm PST), or email at firstname.lastname@example.org.