What term describes the movement of pesticide vapors through the air?

• A. Vapor drift
• B. Pesticide residue
• C. Leaching
• D. Adsorption

Answer: (A)

Vapor drift describes the movement of pesticide vapors through the air from the treated area to off-target areas. This happens when a chemical volatilizes after application and is carried by air currents, wind, and diffusion to nearby surfaces, crops, or people. The distance and impact depend on how volatile the pesticide is, the temperature and humidity, wind speed, and atmospheric conditions. It’s different from leaching, which is movement through soil with water, and from adsorption, which is the chemical sticking to soil or organic matter. It’s also separate from spray drift, which involves liquid droplets moving through the air during application. To reduce vapor drift, applicators use less volatile formulations, apply under favorable weather conditions, and follow label guidance.