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Freshwaters are an essential resource which must be available not only in the required quantity but also in a precise quality. Only less than 1% of the world΄s freshwater resources are readily available for human use, and even this resource is unevenly distributed among the countries. In developed countries, their contamination is the adverse outcome of incomplete wastewater treatment and improper disposal of sewage into surface and groundwater, which are the major renewable resources for sustainable drinking water production. In a vast array of contaminants of anthropogenic origin reaching our water supplies, pharmaceutically active compounds (PhACs) are among the ones with the biggest input into the environment. In the case of the Ebro river basin, pharmaceuticals can enter the environment through the effluent discharges of 186 WWTPs, and at some points, especially in drought periods, the effluents may represent a significant percentage of the total flow of the river. Besides these WWTP discharges other environmental exposure pathways of PhACs can be land applications (e.g., biosolids and water reuse) or concentrated animal feeding operations (CAFOs). The fact that existing WWTPs only treat wastewaters produced by a 62.8% of the basins total population and therefore, that a certain percentage of water remains untreated, may result in lower water quality in some affected areas. Even though pharmaceutical products are, until now, not included in the list of priority or dangerous substances of the Water Framework Directive (2000/60/EC), and thus, no environmental quality standards are stipulated (Directive 2008/105/EC), substances discharged into a basin should be controlled, as the same directive clearly establishes. This chapter will review the levels and distribution of pharmaceuticals detected in both waste and river waters from the Ebro river Basin and gives an example about the use of established hazard indexes to estimate the possible risks posed by the pharmaceutical levels detected towards different aquatic organisms (algae, daphnia, and fish). Results presented in this chapter were integrated in the FP6 European Union project AQUATERRA (contract no. 505428). [ABSTRACT FROM AUTHOR]

Brassinosteroids (BRs) are a class of plant polyhydroxysteroids that have been recognized as a new kind of phytohormones that play an essential role in plant development. BRs occur at low concentrations throughout the plant kingdom. They have been detected in all plant organs (pollen, anthers, seeds, leaves, stems, roots, flowers, and grains) and also in the insect and crown galls. BRs are structurally related to animal and insect steroid hormones. Natural 69 BRs identified so far, have a common 5α-cholestan skeleton, and their structural variations come from the kind and orientation of oxygenated functions in rings A and B. As regards the B-ring oxidation, BRs are divided into 7-oxalactone, 6-ketone (6-oxo) and 6-deoxo (non-oxidized). These steroids can be classified as C27, C28 or C29 BRs depending on the alkyl-substitution on the C-24 in the side chain. In addition to free BRs, sugar and fatty acid conjugates have been also identified in plants. [ABSTRACT FROM AUTHOR]

Occurrence of emerging contaminants in environmental waters is directly related to their removal in wastewater treatment plants (WWTP) and the flow rate of the receiving waters. Mediterranean rivers are characterized by important fluctuations in the flow rates and heavy contamination pressures from extensive urban, industrial, and agricultural activities. This translates in contamination levels most often higher than in other European basins. This paper reviews the data regarding the levels of pharmaceuticals and illicit drugs detected in wastewaters and gives an overview of their removal by conventional treatment technologies applying activated sludge. Pharmaceutically active compounds and illicit drugs are selected as two important groups of emerging environmental contaminants that have raised an increasing interest in the scientific community. Their removal in WWTP, the influence of hydrological conditions in the receiving rivers, and dilution factors are described and examples are provided for selected WWTP and rivers in Catalonia (NE Spain). [ABSTRACT FROM AUTHOR]

There is a growing concern about possible ecotoxicological importance of various classes of emerging contaminants in the environment. Numerous field studies designed to provide basic scientific information related to the occurrence and potential transport of specific classes of emerging contaminants in the environment are being conducted with the aim to identify the sources and points of entry of these contaminants into the environment, and to determine their concentrations in both input streams (i.e., urban and industrial wastewaters) and receiving environment. This chapter summarizes the data regarding the occurrence of emerging contaminants in urban and industrial wastewaters, including some prominent classes such as pharmaceuticals, hormones, illicit drugs, surfactants and their degradation products, plasticizers, and perfluorinated compounds. [ABSTRACT FROM AUTHOR]

This chapter gives the main concluding remarks in relation to the chemical analysis, occurrence, toxicological impact, and different treatment technologies presented in this book, highlighting their possibilities and summarizing future research needs in the area of wastewater treatment of emerging contaminants. [ABSTRACT FROM AUTHOR]