Environment and wastewater

This chapter provides an overview of the analysis of TPs in the environment of three important classes of synthetic chemicals namely pesticides, human and veterinary pharmaceuticals, and personal care products (PPCPs). A series of analytical protocols applied to determine and analyze TPs of manmade chemicals originating from photolysis as well as from microbial degradation in the environment and wastewater treatment plants (WWTPs) is presented. Furthermore, strategies for identifying unknown TPs of xenobi-otic compounds including pesticides and PPCPs are presented based on the combination of mass spectrometric techniques and NMR, IR, and optical detection systems like DAD and FL. 

Conclusions. The impact of plasticizers on the environment is very low and is diminishing as evidenced by analytical data showiag that the levels of phthalates ia surface waters and sediments are decreasiag. This is despite the fact that their usage has continued to iacrease aimuaHy and is most likely due to improved emission controls and wastewater treatment. 

American Water Works Association, American PubHc Health Association, and Water Environment Eoundation, Standard Methodsfor the Examination of Water and Wastewater, 18th ed., American PubHc Health Assc., Washington, D.C., 1992. 

The widespread use of biphenyl and methyl-substituted biphenyls as dye carriers (qv) in the textile industry has given rise to significant environmental concern because of the amount released to the environment in wastewater effluent. Although biphenyl and simple alkylbiphenyls are themselves biodegradable (48—50), the prospect of their conversion by chlorination to PCBs in the course of wastewater treatment has been a subject of environmental focus (51—53). Despite the fact that the lower chlorinated biphenyls are also fairly biodegradable (49,54,55) continued environmental concern has resulted in decreased use of biphenyl as a dye carrier (see Dyes, environmental chemistry). 

It is mandatory for a good paint shop to control polluting fumes and treat wastewater before it is discharged into the drains. To do this, effluent treatment processes must be carried out to prevent pollution of the environment and contamination of ponds, rivers or farmlands, into which the wastewater is discharged. 

The solids that result from wastewater treatment may contain concentrated levels of contaminants that were originally contained in the wastewater. A great deal of concern must be directed to the proper disposal of these solids to protect environmental considerations. Failure to do this may result in a mere shifting of the original pollutants in the waste stream to the fmal disposal site where they may again become free to contaminate the environment and possibly place the public at risk. A more reasonable approach to ultimate solids disposal is to view the sludge... 

Greenberg, A.E., Clesceri, L.S. and Eaton, A.D., Standard Methods for the Examination of Water and Wastewater , 18th edn. American Public Health Association, American Water and Wastewater Association, Water Environment Federation, Washington, DC., 1992. 

It has been recognized for some time that fluids in motion, such as the atmosphere or the ocean, disperse added materials. This properly has been exploited by engineers in a variety of ways, such as the use of smoke stacks for boiler furnaces and ocean ontfalls for the release of treated wastewaters. It is now known that dilution is seldom the solution to an enviromnental problem the dispersed pollutants may accumulate to undesirable levels in certain niches in an ecosystem, be transformed by biological and photochemical processes to other pollntants, or have nnanticipated health or ecological effects even at highly dilute concentrations. It is therefore necessary to rmderstand the transport and transformation of chemicals in the natural environment and through the trophic chain ctrlminating in man. 

The main points of collection and subsequent release of these contaminants into the environment are wastewater treatment plants (WWTPs), where they enter via domestic and hospital sewages or industrial discharges [1]. Some of them are more likely accumulated in sewage sludge, due to their moderate to high hydrophobic... 

The wide spectrum of substances detected in receiving river waters indicates that WWTP outlets are major contributors of pharmaceuticals in the aquatic environment. However, wastewater treatment must be an obligatory and final treatment step prior to their release into the aquatic media, since load of pharmaceuticals in outlets were considerably reduced after treatment. Dilution factor is controlled in the Ebro river but in other areas where the river flow is low, effluents may represent a significant percentage of the total flow of the river. In fact, higher concentrations of total pharmaceuticals were found in areas with lower river flow, and this could situation could be enhanced in drought periods. 

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. 

As occurs with other groups, after administration these drugs are excreted into wastewater, enter the aquatic environment, and eventually can reach drinking water if they are not biodegradable or eliminated during sewage treatment. Data on the environmental occurrence of the pharmaceuticals treated in this section are found in Table 1. 

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