Agriculture Reference
In-Depth Information
Pesticides are more extensively applied as liquids than as solids. Even
some dry formulations, such as wettable powders, are diluted or suspended in a
liquid before being applied. Different formulations present different hazards to
the applicator.
Figure 4.2
describes the hazards of various formulations.
Figure 4.1
Illustration of the different pesticide formulations and packages
available (EPA,
Protect Yourself from Pesticides,
1993).
A. TYPES OF FORMULATIONS
1.
Emulsifiable Concentrates
Emulsifiable concentrates (EC or E are commonly used abbreviations fol-
lowing the trade name on the package) are the most commonly used formula-
tions. The active ingredients in these formulations are insoluble in water.
Thus, they are dissolved in an organic or petroleum-based solvent (which
gives ECs their strong odor); emulsifiers are then added to the solution. The
emulsifiers have properties similar to household detergents and soaps and al-
low the pesticide to be effectively mixed with water. In water, ECs form
"milky" suspensions, called emulsions. Only slight agitation is required to
maintain the suspension.
On the product label, the active ingredient in emulsifiable concentrates is
given as a percentage or as pounds per gallon; concentrations normally range
