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CHEMICAL FORMULATIONS
(Original Courtesy UNIVAR, edited with additions)
PESTICIDES
By definition, a pesticide is simply a product that is used to kill pests.
The following are the most common formulations of pesticides you are likely to come across in
your day-to-day duties. As your experience increases according to the policies of your com-
pany, you will know which pesticides are most appropriate for which specific pest problem. You
will know that there are times when two or more formulations of the same or even different
pesticides are necessary to control the situations that you are facing. You will know that these
formulations are one of the many tools that you will have at your disposal as you go about your
duties.
1. Emulsifiable Concentrates are made from technical materials, which do not mix with water
by themselves. The technical chemicals are thick syrups, crystal-like salts or gummy materials.
Nearly all of them will dissolve in an “oil solvent.” To get this oil and chemical to mix with water,
a chemical called an emulsifier (like soap) is added. Then the concentrate will stay mixed with
the water in your service sprayer. Most emulsifiable concentrates will mix with oil as well as
water for your ready-to-use chemical. There are two levels of emulsifiable concentrates: High,
and Low. In most cases low concentrate liquids contain from 10% active ingredients and often
require no additional mixing. Low concentrate emulsions are used by technicians to control fly-
ing insects. High concentrate emulsions require dilution. From 10% to 80% of an emulsifiable
concentrate can be the active ingredient or technical chemical. These can be used in many
types of application equipment. They tend to have a longer residual than low concentrates.
2. Wettable/Soluble Powders are concentrated powders containing insecticides, which mix with
water to form a liquid ready-to-use material. They are popular due to low cost and the ease of
storage, transportation, and handling. When using wettable powders, technicians must shake
their sprayers frequently and be careful that nozzles and strainers in the sprayer do not clog
because of the powder settling to the bottom of the sprayer.
3. Dusts are technical grade pesticides, which are mixed with a fine dust, which generally has
no effect on pests by itself. Most dusts used by the technician are in ready-to-use form. Dusts
may be stomach poisons, desiccants, and contact poisons.
4. Baits are pesticides mixed into a material attractive to a pest. The pest eats the bait, think-
ing it is food, and is killed by the pesticide inside. There are rodenticide baits and insecticide
baits.
5. Aerosols are pressurized containers holding the correct amount of insecticide, which is
forced through a nozzle on the container, releasing the material into the air. Most containers
are small and easy to handle and are used to cover a large area with small particles of insecti-
cide for the control of flying insects.
6. Other Formulations. The formulations described above are the most common types used
by service technicians. In addition, the technician may occasionally use some of the following
types:
A. Flowable concentrates are wettable powders made into a paste, which are added to water
and used in sprayers.
B. Fumigants are liquids or dusts that change into gases when released, and kill insects or
rodents.
179
CHEMICAL FORMULATIONS
(Original Courtesy UNIVAR, edited with additions)
PESTICIDES
By definition, a pesticide is simply a product that is used to kill pests.
The following are the most common formulations of pesticides you are likely to come across in
your day-to-day duties. As your experience increases according to the policies of your com-
pany, you will know which pesticides are most appropriate for which specific pest problem. You
will know that there are times when two or more formulations of the same or even different
pesticides are necessary to control the situations that you are facing. You will know that these
formulations are one of the many tools that you will have at your disposal as you go about your
duties.
1. Emulsifiable Concentrates are made from technical materials, which do not mix with water
by themselves. The technical chemicals are thick syrups, crystal-like salts or gummy materials.
Nearly all of them will dissolve in an “oil solvent.” To get this oil and chemical to mix with water,
a chemical called an emulsifier (like soap) is added. Then the concentrate will stay mixed with
the water in your service sprayer. Most emulsifiable concentrates will mix with oil as well as
water for your ready-to-use chemical. There are two levels of emulsifiable concentrates: High,
and Low. In most cases low concentrate liquids contain from 10% active ingredients and often
require no additional mixing. Low concentrate emulsions are used by technicians to control fly-
ing insects. High concentrate emulsions require dilution. From 10% to 80% of an emulsifiable
concentrate can be the active ingredient or technical chemical. These can be used in many
types of application equipment. They tend to have a longer residual than low concentrates.
2. Wettable/Soluble Powders are concentrated powders containing insecticides, which mix with
water to form a liquid ready-to-use material. They are popular due to low cost and the ease of
storage, transportation, and handling. When using wettable powders, technicians must shake
their sprayers frequently and be careful that nozzles and strainers in the sprayer do not clog
because of the powder settling to the bottom of the sprayer.
3. Dusts are technical grade pesticides, which are mixed with a fine dust, which generally has
no effect on pests by itself. Most dusts used by the technician are in ready-to-use form. Dusts
may be stomach poisons, desiccants, and contact poisons.
4. Baits are pesticides mixed into a material attractive to a pest. The pest eats the bait, think-
ing it is food, and is killed by the pesticide inside. There are rodenticide baits and insecticide
baits.
5. Aerosols are pressurized containers holding the correct amount of insecticide, which is
forced through a nozzle on the container, releasing the material into the air. Most containers
are small and easy to handle and are used to cover a large area with small particles of insecti-
cide for the control of flying insects.
6. Other Formulations. The formulations described above are the most common types used
by service technicians. In addition, the technician may occasionally use some of the following
types:
A. Flowable concentrates are wettable powders made into a paste, which are added to water
and used in sprayers.
B. Fumigants are liquids or dusts that change into gases when released, and kill insects or
rodents.
166