Pesticides can move from the sites where they are applied into the surrounding environment through drift and volatilization. EPA defines pesticide spray or dust drift as “the physical movement of pesticide droplets or particles through the air at the time of pesticide application or soon thereafter from the target site to any non- or off-target site.”
Volatilization occurs when pesticide surface residues change from a solid or liquid to a gas or vapor after a pesticide application. Once airborne, volatile pesticides can come into contact with applicators or move long distances off site. Not all pesticides are volatile, and the higher the vapor pressure of a given chemical, the higher its volatility will be. Appendix C lists all the pesticides registered for use in New York State with the corresponding vapor pressures. Generally, any pesticide with a vapor pressure greater than 1 millipascal (mPa) is deemed to be volatile. For more information on drift and volatilization, see:
- EPA, Introduction to Drift: http://www.epa.gov/pesticides/about/intheworks/volatilization.htm
- EPA, Pesticide Volatilization: https://www.epa.gov/reducing-pesticide-drift/pesticide-volatilization
- Croplife Foundation, “Minimizing Pesticide Spray Drift” http://croplifefoundation.files.wordpress.com/2012/05/spray_drift.pdf
- Cornell University Pesticide Application, Turf Spraying web page: http://web.entomology.cornell.edu/landers/pestapp/turf.htm
- Preventing Drift, Appendix H
