What increases the likelihood of volatilization to occur?

• A. Temperature decreases and humidity increases.
• B. Temperature increases and humidity decreases.
• C. Temperature increases and humidity increases.
• D. Temperature decreases and humidity decreases.

Answer: (B)

Volatilization is when a pesticide shifts from a liquid or solid on a treated surface into the surrounding air as a vapor. The likelihood of this happening rises when the surface and the air encourage evaporation. Warm temperatures boost volatilization because they increase the pesticide’s vapor pressure and give molecules more kinetic energy to escape into the air. Humidity matters because dry air can hold more vapor; when relative humidity is low, evaporated pesticide molecules are more readily diffused away, so evaporation continues more quickly. In contrast, high humidity means the air is already laden with water vapor, which slows the air’s capacity to take up more pesticide vapor and reduces volatilization. So the combination of higher temperature with lower humidity creates the environment most conducive to volatilization.