Pesticide granules

Myram C, Forrest JD. 1969. The application of pesticide granules from the air. Chem Ind, 1851. 

Most pesticides are sprayed or dusted as dispersions in an inert carrier. Spraying is almost invariably in the form of an aqueous solution and in the case of dusting the carrier is a finely ground cheap mineral of some kind. Direct application of the pesticide granules to the soil for subsequent root absorption is sometimes used, and application to the whole plant in gaseous or smoke form is also occasionally employed. Seed treatment is another technique which has met with some success [22]. 

Uses Warp sizing agent for spun, filament yarns emulsifier molding for films wood-free, specialty paper processing adhesive and binder for inorganic materials, cement, mortar, pesticide granulation, medical tablets, TV Braun tubes, office adhesives, remoisturing adhesives, nonwovens, synthetic leathers, cataplasm, metal surface treatments... 

Pesticide Dispersants. Modified ligaosulfates are used ia the formulatioa of pesticides, la wettable powders, suspeasioa coaceatrates, and water dispersible granules, they act as dispersants and prevent sedimentation. They also act as biaders ia the productioa of granular pesticides. Typical usage levels ia these types of products range from 2—10%. 

The main purpose of pesticide formulation is to manufacture a product that has optimum biological efficiency, is convenient to use, and minimizes environmental impacts. The active ingredients are mixed with solvents, adjuvants (boosters), and fillers as necessary to achieve the desired formulation. The types of formulations include wettable powders, soluble concentrates, emulsion concentrates, oil-in-water emulsions, suspension concentrates, suspoemulsions, water-dispersible granules, dry granules, and controlled release, in which the active ingredient is released into the environment from a polymeric carrier, binder, absorbent, or encapsulant at a slow and effective rate. The formulation steps may generate air emissions, liquid effluents, and solid wastes. 

Approximately 55 different commercial formulations of chlordecone have been prepared since its introduction in 1958 (Epstein 1978). The major form of chlordecone, which was used as a pesticide on food products, was a wettable powder (50% chlordecone) (Epstein 1978). Formulations of chlordecone commonly used for nonfood products were in the form of granules and dusts containing 5% or 10% active ingredient (Epstein 1978). Other formulations of chlordecone contained the following percentages of active ingredient 0.125% (used in the United States in ant and roach traps), 5% (exported for banana and potato dusting), 25% (used in the United States in ant and roach bait), 50% (used to control mole crickets in Florida), and 90% (exported to Europe for conversion to kelevan for use on Colorado potato beetles in eastern European countries) (Epstein 1978). 

After a pesticide is manufactured in its relatively pure form (the technical grade material) the next step is formulation - processing a pesticide compound into liquids, granules, dusts, and powders to improve its properties of storage, handling, application, effectiveness, or safety [9]. The technical grade material may be formulated by its manufacturer or sold to a formulator/ packager. 

Dry products can include dusts, powders, and granules. Dusts and powders are manufactured by mixing technical grade material with the appropriate inert carrier and grinding the mixture to obtain the correct particle size. Several rotary or ribbon blender-type mixers mix the product. Figure 6 shows a typical dry formulation unit for pesticides [8]. 

Formulation is the form in which the pesticide is delivered to the pest. Some types of triazine formulations are flow-able formulation (FF), emulsifiable concentrate (EC), and water-dispersible granule (WDG). 

In another application, Esy-GC-ECD was applied to the extraction of 14 organochlorine pesticides (OCPs) in spiked and contaminated complex samples, such as raw leachate water and soil-water slurry samples.94 A downsized filtration vessel was deemed crucial for sample filtration after acidification and the addition of activated copper granules (to remove elemental sulfur) and 20% acetonitrile (to prevent adsorption and enhance enrichment). Under optimal conditions, extraction of a 3-mL leachate water sample dispensed at a flow rate of 100 pL min-1 gave Ee values between 32 and 242 and LODs between 1 and 20 ng I. It was also demonstrated that, since ESy extraction is dynamic and its extraction efficiency low, calculation of relative recovery was more relevant than extraction efficiency in all ESy applications. 

Dermal Exposure Of the three major routes of exposure, the dermal (skin) route constitutes nearly 90% of chemical exposure, particularly of pesticides. Dermal exposure is common whenever chemicals are mixed or handled. Certain types of dry materials, (e.g., pesticide dusts, wet or dry powders, granules, liquid pesticides) enter the body through quick skin absorption. Many factors influence the rate of dermal exposure of a chemical these may be as follows ... 

Approximately 85% of American homes maintain an average inventory of three to four pesticide products (e.g., pest strips, bait boxes, bug bombs, flea collars, pesticide pet shampoos, aerosols, granules, liquids, dusts). In fact, nearly 70 million... 

Tpo understand the physical and colloidal chemical aspects of pesticidal formulations research, one must first understand the objectives of the formulations chemist in his work. Simply speaking, the formulations chemist must take the pure organic chemical pesticide and put it in a usable form for field use. These forms include wettable powders, emulsifiable concentrates, dusts, granules, water-soluble concentrates, flowables, and an aerosol, to name a few types of concentrates. The formulations chemist desires to put together a formulation that (1) is easy and eco-... 

---