Pyrethroid pesticide, solid

Barrionuevo, W.R. Langas, F.M. Comparison of liquid-liquid extraction (LLE), solid-phase extraction (SPE), and solid-phase microextraction (SPME) for pyrethroid pesticides analysis from enriched river water. Bull. 21. Environ. Contam. Toxicol. 2002, 69, 123-128. 

Pyrethroid type Cereals Nonpolar solvent extraction-solid-phase extraction Differential pulse polaro-graphy of 3-methoxybenz-aldehyde produced from pesticides by alkaline hydrolysis [140]... 

Two synthetic pyrethroid insecticides, bifenthrin and permethrin (3-phenoxybenzyl (lR5)-cis-fra s-3-(2,2-dichlorovinyl)-2,2-dimcthylcyclopropane-carboxylate), are the major runoff constituents considered in our monitoring and evaluation studies. Bifenthrin has a solubility of <1 ppb, and a Koc of240,000 ml g. Permedirin has a solubility of 6 ppb in water, and a Ka- of 100,000 ml g (5). The stroi adsorption on soil suggests that a large fiaction of the pesticide is associated wifii die suspended solids in nursery runoff. This determines that the downstream distribution of these pesticides is closely related to distribution of sediments, and that practices aiming to remove suspended solids from runoff will also be effective in reducing the level of these pesticides. 

The amounts of pesticides passing from raw materials into fruit juices depend on the distribution of residues between the solid (skin or flesh) and liquid fruit portions. Moderately to highly lipophilic pesticides, such as parathion, captan, folpet or synthetic pyrethroids, usually pass to the raw juices only to a very limited extent. A further decrease of their contents may occur during operations such as clarification or ultrafiltration. The risk of infiltration of residues into the human food chain, however, exists when the solid waste with higher concentrations of pesticides is used as an animal feed. 

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