Priority organic pollutants pesticides

The general term organochlorine pesticides refers to many halogenated organic componnds that are being used cnrrently or that were nsed in the past in pesticide formn-lations. Snch substances may differ widely in their chemical structures and, therefore, in their physical and toxicological properties. Some of the most well-known pesticides of this class, many of which listed as U.S. EPA priority enviromnental pollutants, may be structurally classified into the following five types ... 

In the pesticide industry, metals are used principally as catalysts or as raw materials that are incorporated into the active ingredients, for example, metallo-organic pesticides. Priority pollutant metals commonly incorporated into metallo-organic pesticides include arsenic, cadmium, copper, and mercury. For metals not incorporated into the active ingredients, copper is found or suspected in wastewaters from at least eight pesticides, where it is used as a raw material or catalyst zinc becomes part of the technical grade pesticide in seven processes and mercury is used as a catalyst in one pesticide process. Nonpriority pollutant metals such as manganese and tin are also used in pesticide processes. 

There are six primary in-plant control methods for removal of priority pollutants and pesticides in pesticide manufacturing plants. These methods include steam-stripping, activated carbon adsorption, chemical oxidation, resin adsorption, hydrolysis, and heavy metals separation. Steam-stripping can remove volatile organic compounds (VOCs) activated carbon can remove semi volatile organic compounds and many pesticides and resin adsorption, chemical oxidation, and hydrolysis can treat selected pesticides [7]. Heavy metals separation can reduce toxicity to downstream biological treatment systems. Discussion of each of these methods follows. 

In the pesticide industry, steam-stripping has proven effective for removing groups of priority pollutants such as volatile aromatics, halomethanes, and chloroethanes as well as a variety of nonpriority pollutant compounds such as xylene, hexane, methanol, ethylamine, and ammonia [11]. Thus, this process is used to reduce or remove organic solvents from waste... 

Hornsby, A.G., Wauchope, R.D., Herner, A.E. (1996) Pesticide Properties in The Environment. Springer-Verlag, Inc., New York. Horvath, A.L., Editor (1982) Elalogenated Hydrocarbons, Solubility-Miscibility with Water. Marcel Dekker, Inc., New York. Howard, P.H., Editor (1989) Handbook of Fate Exposure Data for Organic Chemicals. Vol. I. Large Production and Priority Pollutants. Lewis Publishers, Inc., Chelsea, Michigan. 

The U.S.A., through the National Pesticide Survey, " which was organized by the Environmental Protection Agency (US-EPA), established a fist of compounds based on the amount used (>7000 Tons), water solubility (>30 mg/1), and hydrolysis half-life (>25 weeks). The list includes some carbamate pesticides (e.g., aldicarb, propoxur, carbaryl, carbofuran, methiocarb, methomyl, oxamyl, cycloate, butylate, propham, and swep) and various derivatives (e.g., aldicarb sulphone, aldicarb sulphoxide, and 3-hidroxycarbofiiran). In Europe, a list of priority pollutants including pesticides was established in order to protect the environment from the adverse ecological impact of these compounds. ... 

Various inorganic compounds (particularly heavy metals) and organic compounds (e.g. pesticides and priority pollutants)... 

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