Pesticides plant effluents

Effluents from pesticide manufacturing facilities are subject to TSCA, and the practical effect is that allegations that pesticide plant effluents have caused a significant adverse effect must be recorded under TSCA 8(c). ... 

Environmental applications of HRP include immunoassays for pesticide detection and the development of methods for waste water treatment and detoxification. Examples of the latter include removal of aromatic amines and phenols from waste water (280-282), and phenols from coal-conversion waters (283). A method for the removal of chlorinated phenols from waste water using immobilised HRP has been reported (284). Additives such as polyethylene glycol can increase the efficiency of peroxidase-catalyzed polymerization and precipitation of substituted phenols and amines in waste or drinking water (285). The enzyme can also be used in biobleaching reactions, for example, in the decolorization of bleach plant effluent (286). 

The USEPA surveys identified nine pesticide plants using full-scale hydrolysis treatment systems [7]. In the industry, a detention time of up to 10 days is used to reduce pesticide levels by more than 99.8%, resulting in typical effluent less than 1 mg/L. The effluents are treated further in biological treatment systems, GAC systems, or chemical oxidation systems, or are discharged to POTWs, if permitted. 

A second plant uses sodium sulfide for the precipitation of copper from pesticide wastewater. Effluent copper concentration can be lowered to 23 p-g/L in this wastewater. 

The use of solvent extraction as a unit process operation is common in the pesticide industry however, it is not widely practised for removing pollutants from waste effluents. Solvent extraction is most effectively applied to segregated process streams as a roughing treatment for removing priority pollutants such as phenols, cyanide, and volatile aromatics [7]. One pesticide plant used a full-scale solvent extraction process for removing 2,4-D from pesticide process wastewaters. As a result, 2,4-D was reduced by 98.9%, from 6710 mg/L to 74.3 mg/L. 

The nitrophenols have been identified in effluents from several industries. 2-Nitrophenol has been detected in effluents from photographic and electronics industries (Bursey and Pellizzari 1982). Nitrophenols (isomer unidentified) at a concentration of 5 mg/L was detected in oil shale retort water (Dobson et al. 1985). Nitrophenols have been identified in effluents from other chemical plants, as well. 4-Nitrophenol has been identified in effluent from a pesticide plant (EPA 1985). Both 2-nitrophenol and 4-nitrophenol were detected in the final effluent from the waste water of a petroleum refining industry (Snider and Manning 1982). Nitrophenols have also been identified in primary and secondary effluents of municipal waste water treatment plants. For example, both nitrophenols were identified in the secondary effluent from a waste water treatment plant in Sauget, Illinois, (Ellis et al. 1982), and 4-nitrophenol was detected in both primary and secondary effluent... 

Pollutants treated in synthetic solutions include phenols, aromatic amines, quinones, glucose, carboxylic acids, tannic acid, herbicides, pesticides, surfactants, dyes, etc. [2-5]. Some papers have considered the treatment of real effluents including human wastes, landfill leachates, tannery wastes, dye plant effluents, and herbicide manufacture effluents [4—7]. 

Sample preparation techniques vary depending on the analyte and the matrix. An advantage of immunoassays is that less sample preparation is often needed prior to analysis. Because the ELISA is conducted in an aqueous system, aqueous samples such as groundwater may be analyzed directly in the immunoassay or following dilution in a buffer solution. For soil, plant material or complex water samples (e.g., sewage effluent), the analyte must be extracted from the matrix. The extraction method must meet performance criteria such as recovery, reproducibility and ruggedness, and ultimately the analyte must be in a solution that is aqueous or in a water-miscible solvent. For chemical analytes such as pesticides, a simple extraction with methanol may be suitable. At the other extreme, multiple extractions, column cleanup and finally solvent exchange may be necessary to extract the analyte into a solution that is free of matrix interference. 

Pesticides in wastewaters come typically from point sources of contamination such as disposal sites and landfills where industrial or agricultural wastes are buried without any consideration, as well as discharges from industrial effluents from pesticide production plants. Furthermore, nonpoint sources derived from regular agricultural activities, especially in intensive agricultural areas, and accidental spills can also be significant. Urban use of pesticides is also possible in large cities where the use of herbicides and insecticides may result in runoff into the sewers. These sewers in turn may expel pesticides into wastewater treatment plants (WWTPs). 

An important number of these substances have an industrial origin. Some of them, like the pesticides, arrive intentionally in the environment and their use and release should be theoretically controlled. However, many of them have not been purposely produced as bioactive substances but more as components or additives of certain materials. Their significant growth in the chemical industry has not only been produced as a consequence of the discovery of new active principles in the pharmaceutical or pesticide area, but also because of the expansion of new technologies (electronics, containers, textiles, plastics, resins, foams, etc.), that require the development of new materials and substances with particular features. Most of these substances enter or are discharged to water and air sources without regulated controls. Wastewater treatment plants (WWTPs) are often not yet adapted to completely remove them, and therefore these new compounds can be found to some extent in wastewater effluents as well as in soil and sludge. 

Surface water can be contaminated by point or nonpoint sources. An effluent pipe from an industrial plant or a sewage-treatment plant is an example of a point source a field from which pesticides and fertilizers are carried by rainwater into a river is an example of a nonpoint source. Industrial wastes probably constitute the greatest single pollution problem in soil and water. These contaminants include organic wastes such as solvents, inorganic wastes, such as chromium and many unknown chemicals. Contamination of soil and water results when by-product chemicals are not properly disposed of or conserved. In addition industrial accidents may lead to severe local contamination. For a more in-depth discussion of sources and movements of water pollutants, see Chapter 27. 

The principles of ecotoxicological quality classification based on the TU index are included in the 2002 recommendations of the Helsinki Commission (HELCOM). The classification applies to samples of treated effluents discharged to waters from industrial plants manufacturing chemicals,98 textiles,99 and pesticides.100 HELCOM recommends testing the acute toxicity of effluent samples using two of the four suggested indicator organisms (Table 9.6). 

For the chlorinated benzenes, a very similar distribution within the sediment core is observed as for some PAHs, e.g. benzo[a]pyrene. An elevated large-scale industrial activity related to these compounds can be deduced for the time between 1947 and 1955. We attribute the decrease in contamination towards the top layers to a reduction of emissions as a result of more efficient sewage treatment plants (Fig. 1A,B) as well as a modified array of products. The concentration profile of HCB (Fig. 6C) and all lower chlorinated benzenes (Tab. 2) suggests the dominance of industrial sources responsible for the contamination as contrasted to agricultural emission derived from pesticide usage. It should be noted that the contamination level of 1,4-dichlorobenzene was elevated in the time period between 1975 and 1980, comparable with concentration levels determined in Rhine river sediments 1982/83. The extensive use of 1,4-dichlorobenzene as an odorous ingredient of toilet cleaners contributed additionally to the contamination via sewage effluents (LWA, 1987/1989). 

There is compelling evidence on the effects of exposure to EDCs on wildlife. These include imposex of molluscs by organotin compounds," developmental abnormalities, demasculization, and feminization of alligators in Elorida by organochlorines, feminization of fish by wastewater effluent from sewage treatment plants, paper mills, and hermaphrodism in frogs from pesticides such as atrazine. ... 

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