Updated: February 2021
What is a pesticide?
Grouping of pesticides
What is a pesticide?
Definition and composition of a
Usually, a pesticide is a product designed to destroy
organisms deemed to be undesirable or noxious. End-use products contain one
or several active ingredients and formulants.
Active ingredient: component of a product to which
is linked the pesticide’s effect. The common name of the active ingredient
appears on the label product under the heading “guarantee”.
Formulant: any component of a pesticide that is
added intentionally and that is not an active ingredient. It improves the
physical characteristics of a pesticide (e.g., sprayability, solubility,
spreadability or stability). Contrary to active ingredients, formulants are
not mentioned on the product label. Kerosene, ethanol, gelatin and soybean
oil are formulants. To learn more about these, please consult the List of Formulants used in pesticides in Canada.
A pesticide is designated by its common name, chemical name
or commercial name.
- The common name refers to the active ingredient. For
example, Roundup, a commercially available product, contains
an active ingredient, known under the common name "glyphosate".
- The chemical name designates the active ingredient
chemical structure name. For example, the chemical name of
glyphosate is "N-(phosphonomethyl)glycine".
- The commercial name is the name given by the
manufacturer. For example, glyphosate is sold under the name
In addition to their usual definition, pesticides also have
a legal definition. These products are designated by two terms: "pest
control products" according to the legislation at federal level, and
"pesticides" at the provincial level.
At the federal level
At the federal level, the Pest Control Products Act includes the
definition of two terms, namely:
"control product" which means a product, an
organism or a substance, including a product, an organism or a substance
derived through biotechnology, that consists of its active ingredient,
formulants and contaminants, and that is manufactured, represented,
distributed or used as a means for directly or indirectly controlling,
destroying, attracting or repelling a pest or for mitigating or preventing
its injurious, noxious or troublesome effects.
"pest" an animal, a plant or other organism
that is injurious, noxious or troublesome, whether directly or indirectly,
and an injurious, noxious or troublesome condition or organic function of an
animal, a plant or other organism.
Any pest control product imported, sold or used in Canada
must be registered by the
Pest Management Regulatory Agency (PMRA) of Health
Canada. By the end of its registration process and before it is marketed,
each product is given a sequential registration number, which must appear on
its label. Registration process is summed up in the document
The Regulation of Pesticides in Canada.
In Canada, 7900 commercial products are registered. You may consult their label contents by using
the Search Product Label tool offered by
the PMRA. Research work can be done in using the active ingredient name,
trade name or product registration number.
It should also be noted that the PMRA combines biopesticides into three main categories: microbial agents, semiochemicals and non-conventional products.
At the provincial level
In Québec, under the
Pesticides Act, the word "pesticide" means any substance, matter or
microorganism intended to directly or indirectly control, destroy, mitigate,
attract or repel any organism that is injurious to or noxious or troublesome
for humans, animal life, vegetation, crops or any other object, or intended
for use as a plant growth regulator, except a vaccine or a medication other
than a topical medication for external use on animals.
Québec legislation applies to
pesticides registered by the PMRA. Moreover, some pest control products are
not subject to Québec legislation, namely:
algicides or bactericides for swimming pools and aquariums
or for the treatment of drinking water
mechanical or physical mechanisms, such as apparatuses to
attract and destroy flying insects, ionizers for algae control in swimming
pools and spas, devices to repel pests by causing physical discomfort by
means of sound, touch or electromagnetic radiation
Although 4,500 products and 600 active ingredients meet the
Québec pesticide definition, only 1,200 products and 370 active ingredients
are actually sold within the province’s territory (Account
of pesticide sales in Québec).
Usually, pesticides are named according to their grouping
which takes into account the product’s target, its origin and chemical
structure, how it is marketed as well as the target site and its mode of
A pesticide can be grouped according to the following
- category of use
- chemical group
- type of formulation
- type of activity
- site or mode of action
Category of use
Most of the pesticides can be grouped according to their
target. Note that the suffix –cide means "to kill."
|Category of use
||Examples of targets
||Microscopic fungi causing plant diseases
- Diplocarpon rosae
causing rose black spot
- Pucciniastrum epilobii causing fir needle rust
- Venturia inaequalis
causing apple scab
- Lamb’s quarter
- Quack grass
- Poison ivy
- Colorado potato beetle
- Hairy chinch bug
- Eastern spruce budworm
- House dust mite
- Maple bladdergall mite
- Two-spotted spider mite
||Nematodes causing plant diseases
- Meloidogyne hapla causing carrot root knot
||Herbaceous and woody
Other pesticides, which name includes –cide as a suffix, such as "ovicide",
"larvicide" or "adulticide", designate substances specifically intended for
destroying insects at the egg, larvae or adult stage. Also, some pesticides’
names end with the suffix –fuge which means "to repel", as in the word
"insectifuge", which means "insect repellent" or "avifuge", which means "bird
Other categories of use exist, which are:
- animal repellent;
- antifouling paint;
- plant growth regulator;
- pruning paint;
- topical medication intended for animals;
- wood preservative.
Usually pesticides are grouped in two categories: organic and inorganic
pesticides. Organic pesticides contain carbon, while inorganic pesticides
contain carbon which can be found only under the form of carbonate or cyanide.
These pesticides are derivatives made from arsenic, mercury, fluorine, sulphur
and copper, as well as derivatives made from cyanide.
can be divided into three groups: synthetic pesticides (developed in
laboratories and manufactured), natural pesticides (from animal, microbial
or vegetal origin) and microorganisms. Inorganic pesticides are mostly
derived from minerals.
A chemical group is formed with pesticides which have a
similar chemical structure.
For example, the chemical structure of atrazine shown in the
following diagrams allows putting this pesticide in the triazines and
Chemical groups established by the Ministère are described in the
Guide for classification of pesticides by chemical
Type of formulation
Pesticides are available in different formulations and can
be obtained under solid, liquid or gaseous form.
Some pesticides are marketed as ready-to-use products, in
other words they do not need any special preparation before application. On
the other hand, others do need to be prepared. For example, some products
may need to be mixed in exact proportions with water before application.
This mixture is usually called a "spray mixture." In this case, preparation
involves diluting a
||Ready to use or to
||Ready to use
||Ready to use
||To be mixed
||Ready to use
||To be mixed
||To be mixed
||Ready to use
Type of activity
Herbicides, fungicides and insecticides can be designated
according to their action on undesirable organisms.
||Is active only on plant parts that are covered with it.
||Absorbed by the plant, this herbicide moves inside it.
||Herbicide that destroys certain plants among those being under
||Controls all of the treated plants.
||Residual A product that breaks down slowly and controls plants over
a long time.
||Action ceases quickly after application and controls plants over a
||Protects the plant prior the disease infection by preventing the
latter to develop.
||Fights a disease which has already developed.
||Acts when insect is in contact with the product.
||Acts when insect inhales the product.
||Acts when insect feeds on product.
Site or mode of action
Pesticides can be grouped according to the site or mode of
action on the undesirable organism on which they act. Several sites or modes
of action are known for herbicides, insecticides as well as fungicides. Here
are some examples:
Insecticides control insects:
- Herbicides control plants:
by inhibiting photosynthesis, or
by reproducing effects of plant growth regulators which they
- Fungicides control fungi:
The list of pesticides groups constituted according the site
or mode of action is available in the federal registration directive
Voluntary Pesticide Resistance-Management Labelling Based on Target
Site/Mode of Action.
Pheromone: A semiochemical produced by an individual of a species that evokes a behavioural response in individuals of the same species.
Registration: An administrative act authorizing the
sale, importation or use of pest control products in Canada.
Semiochemical: A message-bearing substance produced by a plant or animal, or a functionally identical synthetic analogue of that substance, which evokes a behavioural response in individuals of the same or other species.
Topical medication intended for animals: External use product
which acts where it is applied on the animal. These medications relate mainly
to two product ranges: those intended for house pets (for example, shampoo,
lotion, powder, anti-flea collars and tags for dogs and cats) and those
intended for livestock and cattle (for example, insecticide ear tags for