Pesticides are used to control, destroy, attract or repel any animal, plant or other organism that is directly or indirectly, noxious, troublesome or can cause injury.

For example, pesticides are used to control certain species of mosquitoes that carry West Nile Virus (WNV), rodents infesting schools and algae and microorganisms in swimming pools and spas. Pesticides are also used to manage pests that can interfere with the health of an animal, plant or other organism. Example are diseases on crops, fleas on dogs, and face flies on dairy cattle.

At times, managing pests requires the use of more than one tactic. Intergrated Pest Management (IPM) uses a variety of techniques, including cultural, mechanical and biological methods, along with pesticides when necessary, to suppress pest populations. The combination of prevention and treatment tactics can achieve long-term pest control.

Before using a pesticide it's important to consider whether or not alternative ways of controlling a pest are feasible. For example, maintaining a healthy lawn is your best defence against pest infestations.

Pesticides differ from many other substances that enter the environment in that they are not the by-products of a process, but are released intentionally for a specific purpose. Although their biological effects make them valuable, those same effects can pose risks to human and environmental health. That's why responsible use of these products is so important.

When applied according to the label instructions, pesticides can be used safely.