Many Canadians use pesticides such as herbicides, insecticides and fungicides in and around their home, lawn or garden - though the main application is in agriculture.  Pesticides contain an active chemical ingredient as well as other substances which facilitate use or simply carry the active ingredient.  These chemicals can become airborne as fine particles or gases during application or afterwards, as trace amounts from the soil or vegetation.  

Application instructions and restrictions are developed to control the potential off-target drift of pesticides.  Some chemicals may be carried long distances by winds and weather systems, to ecologically sensitive regions.  Environment Canada scientists (in collaboration with Health Canada scientists) are studying how these chemicals move through the atmosphere to ensure that pesticide use remains environmentally safe.  The contribution of pesticides to regional smog is considered to be relatively small, but action is being taken to reduce it further by managing product composition.

Individuals can also take action by using pesticides responsibly, including reducing or eliminating pesticide use whenever possible.

Prevention of pest problems is the best approach to managing pests and limiting pesticide use. Pest problems need to be correctly identified and a check for damage should be done before deciding on action and using a pesticide.

Recurring pest problems are often a sign that practices need to change. When a pesticide is needed, the appropriate product should be selected. Moreover, the pesticide should only be applied when and where the pest is present, and should be used according to label directions.

Before resorting to herbicides, try managing weeds by improving the general condition of the lawn and doing some occasional hand weeding. Minimize use of pesticides by:

• timing applications correctly to avoid the need for repeat treatments,
• using spot treatments rather than broadcast applications,
• only treating the problem area or plants.

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