Chlorinated organic pesticides, solvent systems

Method 1 (cellulose layers). The cellulose powder is washed twice with isopropanol-ammonium hydroxide-water (6 3 1), washed once in isopropanol and dried at 10S °C for 8 h. The plates (thickness, 0.25 mm) are prepared with a commercial TLC applicator. The slurry consists of 15 g of prepared cellulose in 85 ml of water which has been homogenized in a blender. The plates are dried at room temperature, and then eluted with diethyl ether in order to remove organic impurities. The plates are dried in air immediately before use. The pesticides are spotted and developed with appropriate solvent systems. The chromatoplate is dried in air and sprayed lightly with a 0.05% solution of fisetin in isopropanol. The separated spots are observed visually under a UV light at 365 nm (excitation, 370 nm emission, 533 nm). This method has been examined for several types of pesticides including carbamates, organophosphates, triazines and chlorinated hydrocarbons. 

Trans Coastal Marine Services (formerly Envirosystems, Inc.) and Louisiana State University (LSU) have developed several bioreactor systems to facihtate petroleum hydrocarbon mineralization and the bioremediation of organic wood preservatives utilizing an immobilized microbe bioreactor (IMBR) technology. These technologies can treat petroleum hydrocarbons, chlorinated solvents, pesticide-contaminated soils, and contaminated groundwater. 

The feasibility of applying solar radiation as a source of UV-visible radiation has made the photo-Fenton system an economical and competitive process. Within this context an alternative method has been developed based on solar photocatalytic oxidation and natural processes of wastewater treatment [5], as well as sunlight-driven degradations of many compounds, such as EDTA [30], phenols [7,13], pesticides [31-33], surfactants [34], diclofenac [24], formic acid [22], azo-dyes [19], non-biodegradable chlorinated solvents [35], nitroaniline [16], and other organic compounds [21, 36]. 

The complexity of the immune system renders it readily attacked by many chemicals. Such attack may result, for example, in organ damage in the thymus, bone, and lymph nodes as well as in cellular pathology in immunocompetent cells. More than 350 different compounds have been identified as immunotoxinsJ5 6 Table 25.1 contains a representative list of these. This list includes heavy metals, chlorinated and organophosphorus pesticides, aromatic hydrocarbons, polynuclear aromatic hydrocarbons, organic solvents, and many widely used chemicals. Many lipophilic and hydrophilic chemicals are immunotoxins and the immunotoxicity of these compounds is manifest via multiple mechanisms. 

Home Filtration Systems. The same filtration and purification methods used in large water treatment plants have been downscaled for home use. Faucet-mount filters use carbon filtration, ion-exchange filtration, and submicron filtration to reduce sediment, chlorine, lead, mercury, iron, herbicides, pesticides, insecticides, industrial solvents, volatile organic compounds, synthetic organic compounds, and tri-halomethanes (THMs, chlorine and its by-products). These apparatuses rapidly provide filtered water that tastes and smells better with less cloudiness. Shower filters typically use copper-zinc oxidation media and carbon filtration to remove chlorine for softer skin and hair. Whole-house-use water filters are plumbed into the main water line and commonly include a sediment pre-filter, then copper-zinc oxidation media and crushed mineral stone or natural pumice to reduce chlorine, then activated carbon to remove other chemicals. 

The chemicals that are toxic to all three systems include organophosphate, organo-chlorine, and carbamate pesticides, other persistent organic products, heavy metals, solvents, plasticizers, industrial chemicals, and chemicals used in consumer products. 

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