Pesticide mineralization

Uses. Tballium compounds have limited use in industrial appHcations. The use of thaHous sulfate in rodenticides and insecticides has been replaced by other compounds less harmful to animals (see Insect control technology Pesticides). Tb allium sulfide has been used in photoelectric cells (see Photovoltaic cells). A thallium bromide—thallium iodide mixture is used to transmit infrared radiation for signal systems. ThaHous oxide is used in the manufacture of glass (qv) that has a high coefficient of refraction. Tb allium formate—malonate aqueous solutions (Cletici s solution) have been used in mineral separations. Many thallium compounds have been used as reagents in organic synthesis in researchlaboratoti.es. 

Surface-active substances (SAS) are the most widespread contaminants of sewage and natural waters. They translate in small dispertion condition liquid and firm polluting substances - chlororganic, mineral oils, pesticides. Therefore, the SAS contents determination in water solutions is now one of actual tasks of analytical chemistry. 

Contamination of waters with ai senic occurs as a result of a number of industrial activities such as treatment of industrial wastes, fertilizers, pesticides production, mining, metal smelting etc. and natural processes (e.g. weathering of minerals, volcanic and biological activities). 

Chemicals are ubiquitous as air, carbohydrates, enzymes, lipids, minerals, proteins, vitamins, water, and wood. Naturally occurring chemicals are supplemented by man-made substances. There are about 70000 chemicals in use with another 500-1000 added each year. Their properties have been harnessed to enhance the quality of life, e.g. cosmetics, detergents, energy fuels, explosives, fertilizers, foods and drinks, glass, metals, paints, paper, pesticides, pharmaceuticals, plastics, rubber, solvents, textiles thus chemicals are found in virtually all workplaces. Besides the benefits, chemicals also pose dangers to man and the environment. For example ... 

Several applications involve the removal of large amounts of triglicerides, including the determination of wax esters in olive oil (39), sterols and other minor components in oils and fats (40, 41), PCBs in fish (42), lactones in food products (43, 44), pesticides (45), and mineral oil products in food (46,47). Grob et al. (47) studied the capacity of silica gel HPLC columns for retaining fats, and concluded that the capacity of such columns is proportional to their size, although the fractions of the volumes that are then transferred to the GC system grow proportionally with the column capacity. For these reasons, 2-3 mm i.d. LC columns are to be preferred for LC-GC applications. 

In many cases, there is difficulty in preserving residues in samples after collection and prior to pesticide analysis which coincides with a rapid further degradation and mineralization of the pesticide residues under most environmental conditions. Storage stability studies and studies on the reactivity of sample collection equipment in addition to field quality assurance procedures can help address some of these questions. Concerns are accentuated for compounds that have short half-lives in the environment but still have high acute toxicity. 

The pesticide storage situation in the 1960-70s was typical of what was found in Uzbekistan only 40% of 1082 storehouses met health and hygiene requirements [A62]. Towards the end of the 1980s, only 75% of the pesticides used in the USSR were provided with storehouses [1]. A significant number of the chemical substance storehouses (20% in Russia, 23% in Ukraine) did not meet elementary health requirements. In Azerbaijan, there were no specialized storehouses for pesticides at all - these chemicals were being stored together with mineral fertilizers [19]. From that time on, very little has changed. 

Herbicide use in forestry causes mineralization, thus decreasing the amount of organic compounds in the soil, as well as the overall nitrogen and calcium content. It is an immutable fact that pesticides negatively effect agricultural crops. And this influence is much more serious and varied than pesticide proponents believe. 

Chemicals degraded by WRF include pesticides such as organochlorines DDT and its very toxic metabolite DDE [8, 9] and organophosphate pesticides such as chlorpyrifos, fonofos and terbufos [10] polychlorinated biphenyls (PCBs) of different degrees of chlorine substitution [11-13], some even to mineralization [14, 15] diverse polycyclic aromatic hydrocarbons (PAHs) in liquid media and from contaminated soils or in complex mixtures such as creosote [16-18] components of munition wastes including TNT and its metabolites DNT [19-23], nitroglycerin [24] and RDX [25]. 

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