The word "pesticide" is a general term used to describe a substance (or mixture) that kills a pest, or it prevents or reduces the damage a pest may cause. Pests can be insects, mice or other animals, unwanted plants (weeds), fungi, bacteria or viruses.

Pesticides can also include any substance that is used to modify a plant's growth (regulator), drop a plant's leaves prematurely (defoliant), or act as a drying agent (desiccant). Pesticides are usually chemicals, but they can also be made from natural materials such as animals, plants, bacteria, etc.

NOTE: The term "pesticide" describes a very large and diverse group of chemicals or products. It is very important to always get specific information about the exact product you are using.

Examples of pesticides:

Pesticides include a wide range of products - many of which you may use every day. The table below lists some common categories, their purpose, and what products they are normally found in. There are many, many more types of pesticides than what is listed here.

Different forms of pesticides:

Pesticides are formulated (prepared) in liquid, solid and gaseous forms.

  • Liquid formulations include suspensions (flowables), solutions, emulsifiable concentrates, microencapsulated suspensions, and aerosols.
  • Solid formulations include dusts, particulates, granulars, pellets, soluble granules, soluble powders, baits, tablets, dry flowables and wettable powders.
  • Gaseous pesticides are typically fumigants (can be sold as liquids or gases).

Abbreviations are often used with the trade name on the pesticide label to indicate the type of formulation. Some examples of words and abbreviations used for pesticide label formulation statements are:

D - Dust or Powder
DF - Dry Flowable
E or E C - Emulsifiable Concentrate
F - Flowable
G - Granular
P - Pellet
S - Solution
SC - Sprayable Concentrate
SP - Soluble Powder
WDG - Water Dispersible Granules
WP - Wettable Powder
WS - Water Soluble Concentrate

Health effects are associated with pesticides:

Pesticides are designed to kill "pests", but some pesticides can also cause health effects in people. The likelihood of developing health effects depends on the type of pesticide and other chemicals that are in the product you are using, as well as the amount you are exposed to and how long or often you are exposed.

Most often, pesticides affect the nervous system (system in your body that controls your nerves and muscles). General health effects from acute (short-term) exposures or poisonings are listed in the table below.

NOTE: The term "pesticide" describes a very large and diverse group of chemicals or products. It is very important to always get specific information about the exact product you are using.

Some health effects from pesticide exposure may occur right away, as you are being exposed. Some symptoms may occur several hours after exposure. Other effects may not be noticed for years, for example cancer.

Some symptoms of pesticide exposure will go away as soon as the exposure stops. Others may take some time to go away. For people exposed to pesticides on a regular basis, long-term health effects are a concern.

Women who are pregnant or breast-feeding should check with their doctors before working with pesticides as some pesticides may be harmful to the fetus (unborn baby) or to breast-fed infants.

Certified pesticide applicators or people who work with pesticides are encouraged to have regular medical check-ups. Tell your doctor which pesticides you are working with and/or exposed to.

Pesticides enter our bodies:

Pesticides can enter your body during mixing, applying, or clean-up operations. There are generally three ways a chemical or material can enter the body:

  • through the skin (dermal),
  • through the lungs (inhalation), or
  • by mouth (ingestion).

Dermal (absorption through skin)

In most work situations, absorption through the skin is the most common route of pesticide exposure. People can be exposed to a splash or mist when mixing, loading or applying the pesticide. Skin contact can also occur when you touch a piece of equipment, protective clothing, or surface that has pesticide residue on it.

Inhalation (through the lungs)

Inhalation may occur when working near powders, airborne droplets (mists) or vapours. The hazard from low-pressure applications is fairly low because most of the droplets are too large to remain in the air. Applying a pesticide with high pressure, ultra low volume, or fogging equipment can increase the hazard because the droplets are smaller and they can be carried in the air for considerable distances. Pesticides with a high inhalation hazard will be labelled with directions to use a respirator.

Ingestion (by mouth)

While ingestion (by mouth) is a less common way to be exposed, it can result in the most severe poisonings. There are numerous reports of people accidentally drinking a pesticide that has been put into an unlabelled bottle or beverage cup/container (including soft drink cans or bottles). Workers who handle pesticides may also unintentionally ingest the substance when eating or smoking if they have not washed their hands first.

Can people become allergic to pesticides?

Fortunately, few of the thousands of pesticides used today cause true allergies. This is because pesticides are tested for their potential to cause allergies prior to being put on the market. However, over time, an allergic reaction to some pesticides or chemicals used in the formulation of some pesticides can develop in some people.

There are two types of allergic sensitization: skin and respiratory. Symptoms of skin sensitization may include swelling, redness, itching, pain, and blistering. Respiratory sensitization symptoms may include wheezing, difficulty in breathing, chest tightness, coughing and shortness of breath. In some cases, respiratory sensitization can produce a severe asthma attack.

As the allergy develops, the reaction can become worse with each exposure. Eventually, even a short exposure to a low concentration of the pesticide can cause a very severe reaction. Although it is rare, it is important to be aware that pesticides may have the ability to cause life threatening allergic reactions in some people.

Information is found on a pesticide label:

Important information is found on the labels of pest control products, and includes:

Symbols and signal words mean:

The symbols and signal words on the pesticide label give you some quick information about the acute toxicity of the product. See Table 2 for the different types of hazard symbols

Work safely with pesticides:

The importance of working safely with or near pesticides cannot be over emphasized. Always read the label and follow the directions. Always follow all of the safety instructions. Many incidents occur when pesticides are being mixed or prepared for use.


  • Use the right pesticide for the job. Make sure the label lists the pest you wish to control.
  • Select the least hazardous pesticide that will still be effective.
  • Always wear the appropriate personal protective equipment (PPE) as recommended on the label, Material Safety Data Sheet (MSDS) or product fact sheet. PPE may include coveralls, long pants, long sleeved shirts, gloves, boots, goggles, face shield, hat, and/or a respirator.
  • Always read the label. Keep the label "intact" and make sure it is readable.
  • Keep the pesticide in its original container. If you must pour the pesticide in a new container, clearly label any new container holding the pesticide. Do not transfer pesticides to cups, bowls or any other container that may be confused with containers for drinking or eating.
  • Clean up spills immediately and dispose of the waste according to directions on the label.
  • Dispose of empty containers according to directions on the label.


  • Do not use products for uses other than what they are intended for.
  • Do not use more pesticide than is recommended (twice the product will not have more effect).
  • Never burn pesticides or pour them down a drain.

When mixing pesticides?


  • Be sure there is good ventilation and lighting in the area where you are mixing the pesticide.
  • Always mix the pesticide at the recommended rate and amounts. Do not "guess" with the measurements.
  • Calculate how much product you will need ahead of time so you don't make too much. Apply the minimum amount of pesticide that is effective.
  • Keep the container below your eye level to help avoid splashing or spilling the pesticide into your eyes and face.
  • Many spray pesticides are flammable. Be sure to follow the instructions carefully.
  • Have a knife or scissors that are used ONLY for opening pesticide bags.


  • Do not create dusts or splashes when opening a container or pouring liquids. Do not tear bags open.
  • Do not use the same knife or scissors to open the bags that you use with food.

When applying pesticides:


  • Keep equipment in good working order. For example: do not use sprayers with leaking hoses or loose connections.
  • Post signs in areas where pesticides are going to be applied, and when re-entry is recommended.
  • Schedule applications when other workers are least likely to be exposed - after hours or when people are not present - at the end of the day, or weekends.
  • Always apply the pesticide at the recommended time and under favourable weather conditions. Never spray on a very windy day, and make sure the spray blows away from you or anyone else.
  • Minimize drift by reducing the distance between the nozzle and the target area. Use the type of nozzle that gives the largest but still effective droplet size.
  • Provide temporary extra ventilation, where necessary, to remove pesticide vapour or aerosol when spraying indoors.
  • After applying, keep away until the pesticide has dried or until the "re-entry" time indicated on the label as passed.
  • Always follow the recommended waiting time between pesticide application and the harvest (picking or eating) of fruits or vegetables.
  • Clearly label treated surfaces where pesticide residues may remain.
  • After spraying, all surfaces that may contact food must be washed and rinsed with water before re-use.


  • Do not use your mouth to siphon liquids from containers or to blow out clogged lines, nozzles, etc.
  • Do not mix, spray, or dust "into" the wind.
  • Be careful when working or spraying near other people, livestock, other crops or when near streams, ponds, lakes and other bodies of water. Pesticides can easily run off or drift into other areas.
  • Do not spray near other people, pets/animals, children's toys, food, dining dishes, etc.
  • Never place rodent or insect baits and traps where children or pets can reach them.

Pesticide spills:

  • Isolate the spill area and ventilate if indoors.
  • Wear the correct personal protective equipment - unauthorized people and those without protection should be kept out of the spill area.
  • Use an absorptive material for liquid spills such as activated charcoal, or vermiculite.
  • After a spill has been absorbed, the contaminated area should be scrubbed with a bleach/ detergent mixture at least two times.
  • For specific clean up and disposal information, read the MSDS. Contact the pesticide manufacturer if you need more information.