Granular formulations

Clays composed of attapulgite, montmorillonite, and kaoHnite are used for pesticides in finely pulverized or granular form. Granular formulations are reportedly less expensive, more easily handled, reduce loss caused by wind drift, and produce a more effective coverage. 

OPs are often applied as sprays. Commonly, the formulations used for spraying are emulsifiable concentrates, where the OP is dissolved in an organic liquid that acts as a carrier. OPs are also used as seed dressings and as components of dips used to protect livestock against ectoparasites. Some highly toxic OPs have been incorporated into granular formulations for application to soil or to certain crops. 

Dispersible granular formulations can be mixed using the procedure described above with the exception that all of the pre-measured water can be poured into the bucket or container. The test item granules are then poured into the water and allowed to dissolve for a few minutes before mixing. In some rare instances, the test item may be difficult to get into solution, and any problems should be recorded. 

Ahmad, N., D.D. Walgenbach, and G.R. Sutter. 1979. Degradation rates of technical carbofuran and a granular formulation in four soils with known insecticide use history. Bull. Environ. Contam. Toxicol. 23 572-574. 

Hill, E.F. and M.B. Camardese. 1984. Toxicity of anticholinesterase insecticides to birds technical grade versus granular formulations. Ecotoxicol. Environ. Safety 8 551-563. 

Chapman RA, Harris CR, Tolman JH, et al. 1994b. The persistence of insecticidal chemical, insoils treated with granular formulations of disulfoton and their uptake by potato plants. J Environ Sci Health Part B Pest Food Contamin Agric 29(2) 233-245. 

Iwata, Y, Carman, G.E., Dinoff, T.M., and Gunther, F.A. Metaldehyde residues on and in citrus fruits after a soil broadcast of a granular formulation and after a spray application to ciUus Uees. J. Agric. Food Chem., 30(3) 606-608, 1982. 

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