EC formulations comprising organophosphate insecticides

Solvent formulations under EC form comprising (% by weight): 10-40% of one or more compounds having an insecticidal activity selected from the organophosphate class; 1-20% of an additive (A) methyl or ethyl esters of carboxylic acids having a C10-C20 chain, saturated or unsaturated, or mixtures thereof, the fatty acids deriving from vegetal oils; 0.5-10% of an additive B) of a cellulose derivative soluble in the organic solvent of EC formulation; 3-15% of one or more surfactants selected from non ionic and anionic surfactants, or thereof mixtures; the complement to 100% being of one or more organic solvents having the following characteristics: capable to solubilize the active principle, expressed as % by weight, at room temperature (20-25° C.) for at least 5%; preferably 10%, more preferably at least 20%, immiscible with water.