Pesticide residues, polymeric

Previous research aimed at removing pesticide residues from contaminated fabrics has been directed at removal of a particular pesticide chemical and/or formulation of pesticide, with no effect toward comparing the pesticide residue s composition to that of common soil. Fabric selection for this study allowed a comparison of both hydrophilic and hydrophobic fibers and the effect of fabric type on soil removal. Two fabrics were identified for the study. Denim was 100% cotton fabric of twill weave dyed with indigo dyes. This fabric was 14 ounce, comparable to the heavy weight denim found in jeans. The second fabric was Gore Tex, a three layer structure consisting of an outer layer of rip-stop nylon and an inner layer of nylon tricot laminated to a film. The film was a micro-porous, polymeric film or polytetrafluoroethylene (PTFE). Previous studies on pesticide penetration found Gore Tex to be impermeable to pesticides. Thermal comfort studies found it to be relatively comfortable, similar In comfort to the commonly worn denim jeans and a chambray shirt. 

Most active principles and pharmaceutical forms are processed in the presence of organic solvents or reagents. The current regulations on products generally restrict to a few p.p.m. the amount of residual solvent. This very low concentration level could favour the CO2 utilization when non-polar compounds have to be eliminated. On the other hand, the elimination of residual solvents from tablets, films or other pharmaceutical preparations in which organic solvent are involved has been addressed [15]. Another application is related to the removal of residues from medical materials such as monomers, additives or polymerization residues from polymers or elastomers. Purification of active principles includes elimination of other undesired molecules pesticides from some vegetal extracts, and antibacterials suspected of toxic co-extracts from natural sources. 

Reduction of aromatic nitro groups occurs in three steps, via nitroso and hydroxylamine intermediates, to the amine. The amine can go on to form polymeric residues by a mechanism analogous to that for oxidative coupling of phenols, as in Equation 2. Abiotic nitro reduction is well documented for pesticides that contain aromatic nitro groups, such as the phosphorothioate esters methyl and ethyl parathion (22, 30-33). 

The quality of a refined oil is usually evaluated by traditional quality parameters such as a low residual FFA content, a high oxidative stability, a light color, and a neutral odor and taste. In addition, high-quality food oils should contain low transfatty acid (TEA) levels, high amounts of natural antioxidants and vitamins, low levels of polymeric and oxidized triacylglycerols, and no contaminants (pesticides, polycyclic aromatic hydrocarbons, dioxins and polychlorinated biphenyls, etc.) (Tables 5 and 6). 

While the conjugates are safely trapped to the cell wall as the plant is alive, the soluble conjugates in the vacuole may become liberated quickly after the plant is dead. Research showed that polymerization of xenobiotics into lignin did not prevent the bioavailability. Sandermann demonstrated that dichloroanilin in wheat straw was liberated when feeding animals. Research about the availability of residues is mainly focused on pesticides, insecticides, and drugs. A similar research on ordinary contaminants will shed light on the study of phytoremediation. 

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