Pathways of pesticide spread in the environment

Gone with the wind

Wind drift. Some of the pesticides sprayed on a field are blown away by the wind. Measurements have shown that between 1 and 5% of the amount sprayed is usually lost through wind drift. The single most important factor is windspeed at the time of spraying. An increase in windspeed of a few metres per second can double the amount of pesticide carried away with the wind. There is then a risk of the pesticide causing direct damage to the surrounding flora and fauna or being spread further in the environment.

Evaporation. A proportion of the pesticide can evaporate from soil and crop to the air. Measurements show that up to 10% of the amount sprayed can disappear through evaporation, in some extreme cases up to 90%.

Pesticides can be transported away in the air through wind drift and evaporation and then carried back to soil or water by rainfall