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Pesticides

Pesticides are used to control pests that can affect our health, safety or food supply. This use of pesticides is called non-cosmetic because it’s needed for public health and safety.

Pesticides are also used to make lawns, gardens and other green spaces look better. We call this use cosmetic because it’s not needed for health and safety.

Studies show that there may be a connection between pesticides and cancer in adults and children. That’s why you should reduce – and even eliminate – exposure to pesticides where possible.

Pesticides are a group of chemicals that include:

  • insecticides – for insect control
  • herbicides – for weed control
  • fungicides – for control of disease caused by fungus
  • rodenticides – for rodent control
  • fumigants – a gas or vapour used to control insects
  • all other types of pesticides – for example, microbials or chemicals to control algae, slugs and insect eggs

Our position on the use of pesticides depends on what they are being used for.

  • Our position on cosmetic use of pesticides

    The Society strongly supports for a ban on pesticides used to improve the appearance of green spaces. The cosmetic use of pesticides provides no health benefit and may cause harm.

    The precautionary principle

    The evidence about pesticides and cancer is not definite, but some research studies show a stronger link between some types of pesticides and cancers. Our position is based on the precautionary principle, which states, “When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause-and-effect relationships are not fully established scientifically.” (If something may cause harm to humans or the environment, we should be cautious even if the link is not definite yet.) The Society supports the use of safer ways to maintain and improve the appearance of lawns, gardens, parks and other green spaces but does not support the use of Integrated Pest Management for cosmetic purposes.

    Golf courses and sporting facilities

    The Society wants the use of pesticides to be phased out at golf courses and sports facilities, especially where children often are, or if they are located next to residential and public areas.

    Pesticides should be used as the last option, in the smallest possible amount and only where needed to make a place usable. People should stay away from treated areas for at least 48 hours after the last amount of pesticide is applied.

    Home fruit and vegetable gardens

    The use of pesticides in home or personal fruit and vegetable gardens should also be phased out. Although the pesticides you use at home may be milder than those used for agriculture, and you may use them less often, there is still risk.

    In the agriculture business, there are usually more rules in place to reduce exposure, such as training for people who apply pesticides to properly use equipment that protects them, plans to reduce residue levels and pesticide drift, and rules to limit access to sprayed areas.

  • Our position on non-cosmetic use of pesticides

    The Society strongly supports that when pesticides are needed to protect our health, safety or food supply, they should be part of a plan that includes pest prevention, using pesticides in the lowest amounts possible and using safer choices.

    The risks and benefits of the non-cosmetic use of pesticides should be judged depending on each situation. Where pesticides are necessary to protect our food supply or against the spread of disease, the Society recommends that:

    • The choice of chemicals should take into account their potential long-term health effects, like the risk of developing cancer in later years. 
    • Widespread chemical spraying should be used only as a last option to protect human health and safety. 
    • If chemical spraying is needed, people must be warned about the risks and helped to protect vulnerable family members such as infants, elderly people and people with weak immune systems.
    • Guidelines that are based on evidence should be set up to help people decide which chemical treatments to use.
    Using pesticides in agriculture

    We encourage farming practices that reduce the use of pesticides. The Society strongly believes that efforts to reduce the use of pesticides in agriculture need to be carefully balanced with efforts to protect:

    • food security – the safety, quality, availability and cost of food
    • the health of Canadians 
    • the environment 
    • the economic stability of farmers and other food producers
  • How you are exposed to pesticides

    People can be exposed to pesticides at home or in the community in several ways:

    • through the skin – absorption; passing into the body through the skin
    • breathing into the lungs – inhalation
    • swallowing – by eating what remains on vegetables and fruit, drinking contaminated water or touching contaminated hands to mouth
    In your home
    • pesticides used outdoors on lawns and gardens
    • insect repellents – for example, for mosquitoes
    • pesticides used indoors – for example, for ants, termites and cockroaches
    • pesticides carried into the home from outdoors – for example, people working with pesticides who bring what remains on their clothing into the home
    In your community
    • pesticides carried in the air, water or soil contaminated by a nearby treated area – for example, drift from a farm or a neighbour’s lawn
    • public health and safety use – for example, community spraying to control mosquitoes
    • pesticides used in parks, recreational areas and other community settings
    In your diet
    • small amounts of pesticides on your vegetables and fruit left behind from growing, storage or transport
    • drinking water contaminated by pesticides – for example, because of drift from a treated area
    At your job
    • pesticides used to protect growing crops, stored crops and livestock from damage on farms 
    • pesticides used to preserve foods for transport 
    • pesticides used on green spaces for recreation or sports – for example, on golf courses
    • making or transporting pesticides

    Pesticides and children
    Children are at risk of being exposed to higher levels of pesticides than adults because:

    • Some activities increase their exposure – such as crawling and playing in grass or gardens treated with pesticides or putting contaminated objects in their mouth. 
    • Pesticides can be absorbed through their skin more easily. 
    • They take in more air, water and food relative to their body weight compared to adults, which increases their total exposure.

    Pesticide exposure may do more harm to children because their bodies are still developing and may not be able to deal with these substances.

    Children can also be exposed to potentially harmful pesticides through their parents. For example, there is evidence that children whose parents work with pesticides are at increased risk of exposure to pesticides in the home. Another possible type of exposure is prenatal (before birth). Some studies suggest that the timing of exposure, such as prenatal exposure to pesticides may be important, but more research is needed to know how this may affect cancer risk in children.

  • Pesticides and cancer

    Pesticides are a group of many different chemicals. The International Agency for Research on Cancer (IARC), the US Environmental Protection Agency and the National Toxicology Program classify pesticides according to their link with cancer. Find out more about how cancer-causing substances are classified.

    IARC has classified the pesticide lindane, as well as pesticides containing arsenic, as known carcinogens. The use of arsenic in pesticides is restricted in Canada, although arsenic is found in some pesticides used to preserve wood for non-residential purposes. Lindane is prohibited for use as a pesticide in Canada. In the past, lindane was used as a treatment for head lice, but products containing lindane for head lice treatment are no longer available in the Canadian market. If you find any products for lice treatment containing lindane in your home, talk to your local pharmacist about a safe way to dispose of the product.

    Research does not show a definite link between most of the pesticides studied and human cancer, but it does suggest a possible connection with cancers such as non-Hodgkin lymphoma, multiple myeloma, chronic lymphocytic leukemia, and prostate, testicular, pancreatic, lung and non-melanoma skin cancers. Studies of pesticides and childhood cancer show a possible connection with leukemia, and non-Hodgkin lymphoma. A possible link between childhood brain cancer and parents’ exposure to pesticides at work has been studied, but there is not enough evidence to make a conclusion.

    Farmers exposed to higher levels of pesticides
    Studies have been done of people who apply pesticides on farms to find out how many of these people get cancer and how many die from it. The results suggest that this group may have a slightly higher risk than the average person of developing non-Hodgkin lymphoma, leukemia, multiple myeloma, and cancers of the prostate and brain.

    One study from the US Agricultural Health Study found that men who applied pesticides had higher rates of prostate cancer compared with the average man. Also, another study suggested that people who are exposed to pesticides at work, such as farmers and farm workers, may be at a higher risk of myeloid leukemias, particularly acute myelogenous leukemia.

    More research needed
    Current research on pesticides doesn’t give us all the information we need:

    • There is only a small amount of research about exposure to pesticides in Canada – information is often from other countries that may have different exposure patterns and types of pesticides.
    • The lack of accurate information about exposure and health outcomes makes it hard to study the link between pesticides and cancer.  
    • Changes over time in the types of pesticides available and in their use can make it hard to understand the health risks of current products.
  • Tips to reduce your exposure
    Pesticides spraying
    • Stay indoors with your family and pets if a neighbour or someone else is using pesticides near your home. Keep your windows and outside doors closed. 
    • Ask your neighbour to tell you if pesticides will be sprayed on their lawn. Keep your family – especially your children and pets – away for at least 48 hours from those areas. 
    • Look out for signs posted on green spaces that show they were recently sprayed with pesticides and don’t walk or play in these areas.

    If you live, work or play near farming areas where pesticides are used:

    • Wait at least 48 hours before going into areas that have been sprayed. 
    • Ask your community to make sure signs are posted in sprayed areas. 
    • Stay indoors when pesticides are being applied and keep windows and outside doors closed.

    Lawn and garden
    Exposure to pesticides should be reduced to the lowest possible level. If pest control is needed for your lawn or garden, try to use safer options. The Canadian Cancer Society recommends the following alternatives:

    • Dig out weeds at their roots. 
    • Keep lawns watered enough but not over-watered – 2 cm of water (less than 1") should be enough. Put a container on your grass when you water to help you measure. 
    • Never cut more than one-third of the height off your grass. If you do, it may leave your lawn open to weeds and diseases.
    • Cut your grass shorter in the spring and then let it grow longer through the summer – this will help make sure strong roots develop. 
    • Aerate your lawn to allow moisture and nutrients to reach the roots of the grass. 
    • Rake your lawn with a heavy rake if needed to remove dead grass and roots that can build up above the soil surface.
    Pesticide residues on vegetables and fruit
    • Pesticides are used during the growing season or to store and transport fresh vegetables and fruit. Sometimes traces of pesticides (residues) are left behind. You can reduce and often eliminate pesticide residues on the fresh vegetables and fruit you eat if you:
      • Wash all fresh vegetables and fruit thoroughly with lots of running water. 
      • Use a small scrub brush to clean the skin of vegetables and fruit if the skin will be eaten – for example, apples, potatoes and cucumbers.  
      • Peel off the outer skin of vegetables and fruit and trim the outer leaves of leafy vegetables, and then wash thoroughly.
    Protecting yourself and others at work
    • Carefully read the product information about pesticides and follow the directions on the label. 
    • Reduce the amount of pesticides used. 
    • Reduce drift and environmental contamination. For example, add a buffer zone – leave a strip of land without pesticides next to a sprayed area. Spray pesticides on days with no wind when the temperature is below 25 degrees Celsius. 
    • Do not use pesticides around children or pets. 
    • Follow work health and safety requirements in your province – for example, when you can return to an area treated with pesticides. 
    • Wear protective equipment (for example, gloves and masks) as recommended on the pesticides label, and remove contact lenses before spraying. 
    • Don’t wear clothing at home that was used while working with pesticides – clothing worn at work should be washed separately and after each use. 
    • Don’t smoke, drink or eat when handling pesticides. Do not rub your eyes or touch your mouth while working with or after using pesticides. Wash your hands immediately after using pesticides. 
    • Never store pesticides near food or drinks. 
    • Never move pesticides into another container from the original one for storage. This will stop you or someone else from mistakenly misusing them. Also, do not throw out the safety instructions from the original label. 
    • Get rid of pesticide containers by following the instructions on the label. Contact the city or town office in your area about getting rid of unused pesticides. 
    • Store pesticides out of children’s reach. 
    • Post signs warning people that an area will be treated with pesticides.
  • Suggested links for more information about pesticides

    General information about pesticides
    These websites provide information about the proper use of pesticides for the public and for commercial users, regulations about the use of pesticides in Canada and the US, and how pesticides may affect your health.

    Health Canada – Pesticides and Pest Management

    National Pesticide Information Center (United States)

    Safer alternatives for home and garden
    These Health Canada website pages provide information for the public about how to rely less on pesticides to safely maintain lawns, safe alternatives to pesticides, and tips for protecting your family from mosquitoes and other pests.

    Pests and Pesticides

    Protect yourself on the job
    These websites provide information for people who may work with pesticides or be exposed to them at work, and tips to safely mix, apply and store pesticides on the job.

    Canadian Centre for Occupational Health and Safety – Pesticides – Working Safely

    World Health Organization – Preventing health risks from the use of pesticides in agriculture

    Environmental Protection Agency (US) – Worker Safety and Training

    Pesticides and food safety
    These websites provide information about how the Canadian government monitors pesticide residues on foods sold to the public.

    Health Canada – Pesticides and Food

    Canadian Food Inspection Agency

    Pesticide regulations in Canada
    These Health Canada website pages provide information about the responsibilities for each branch of government (federal, provincial/territorial, municipal) in regulating pesticide use.

    Pest Management Regulatory Agency

    Regulation of Pesticides in Canada

    Pest Control Products Act

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