Crop spraying is the most often cited cause of air pollution arising from agricultural activities. It is often the preferred means of pesticide application be cause it distributes chemicals efficiently and evenly over large surfaces faster than by other methods. However, for these same reasons, agrochemicals can be distributed outside the areas of treatment and are difficult to contain. Micro-droplets of agrochemicals applied aerially, through heavy spaying for example, may be carried by the wind onto neighbouring water bodies, forest, wildlife habitats, human settlements and fields.