Chlorinated pesticides bacteria

Bacteria, algae, and diatoms that accumulate on the coarse sand layer of the filter bed metabolize nutrients, etc., from the supply, thereby removing them. Among the benefits of slow filtration is removal of up to 50% of any chlorinated pesticide content of the influent water [6]. Slow filtration may require a prior aeration step to ensure that the biochemical processes remain aerobic, since anaerobic operation can form sulfides and amines from sulfate and nitrate, which would contribute bad odors or tastes to the supply. 

Cell components or metabolites capable of recognizing individual and specific molecules can be used as the sensory elements in molecular sensors [11]. The sensors may be enzymes, sequences of nucleic acids (RNA or DNA), antibodies, polysaccharides, or other reporter molecules. Antibodies, specific for a microorganism used in the biotreatment, can be coupled to fluorochromes to increase sensitivity of detection. Such antibodies are useful in monitoring the fate of bacteria released into the environment for the treatment of a polluted site. Fluorescent or enzyme-linked immunoassays have been derived and can be used for a variety of contaminants, including pesticides and chlorinated polycyclic hydrocarbons. Enzymes specific for pollutants and attached to matrices detecting interactions between enzyme and pollutant are used in online biosensors of water and gas biotreatment [20,21]. 

Most faucet units and pitchers use carbon filters that absorb lead, chlorine by-products, and some organic chemicals, as well as odors and tastes. They won t remove heavy metals, pesticides, nitrites, bacteria, or microbes, but they are the least-expensive filter type and are sufficient for most needs. 

Hydrolytic Reactions. Many pesticides possess bonds that are susceptible to hydrolytic attack. These reactions are most easily characterized according to the type of bond hydrolyzed carboxjlic acid ester, carbamate, oiganophosphate, urea, or chlorine (hydrodechlorination). In many instances the specific hydrolytic enzymes have been purified and characterized and the genes encoding for the enzymes isolated and cloned. It is commonly observed that there are multiple forms of the enzymes catalyzing a particular hydrolytic reaction, which suggests that these catalytic functions have evolved independendy in different bacteria (19). 

Currently, waterborne toxic chemicals pose the greatest threat to the safety of water supplies in industrialized nations. This is particularly true of groundwater in the U.S., which exceeds in volume the flow of all U.S. rivers, lakes, and streams. In some areas, the quality of groundwater is subject to a number of chemical threats. There are many possible sources of chemical contamination. These include wastes from industrial chemical production, metal-plating operations, and pesticide runoff from agricultural lands. Some specific pollutants include industrial chemicals such as chlorinated hydrocarbons heavy metals, including cadmium, lead, and mercury saline water bacteria, particularly coliforms and general municipal and industrial wastes. 

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