WaterSubject

Contamination of soils and groundwater by toxic and/or hazardous organic pollutants is a widespread environmental problem and the removal of hydrophobic organic compounds (HOCs) from them has become a major concern. Surfactants can increase the solubilities of HOCs by partitioning them into the hydrophobic cores of surfactant micelles above the critical micelle concentration (CMC) and then enhancing the desorption and flushing of HOCs from solid into aqueous phases, which would improve the bioavailability of HOCs for microbial remediation and phytoremediation. A few ... Read More

The interaction between precipitation, soil moisture, and evapotranspiration is fundamental for understanding water-limited ecosystems. One approach to modeling this interaction is to consider the problem of water balance at a point. In this setting, a probabilistic viewpoint is natural – where uncertainty arises from the intermittent nature of rainfall. Within this framework, one obtains expected values and variances for seasonal evapotranspiration. Thus one can obtain a direct understanding of the impact changes in the rainfall structure and the instantaneous evapotranspiration functions have ... Read More

Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Acinetobacter baumannii ("waterborne pathogens") are Gram-negative bacteria commonly present in chlorinated potable water. These organisms are opportunistic pathogens which do not pose a threat to the general public. However, these organisms have been epidemiologically linked to hospital-acquired respiratory infections in the intensive care units which affect millions of hospitalized patients. The hospital potable water system can be the reservoir responsible for these hospital-acquired infections. It has been suggested that waterborne pathogen-related infections could be prevented by avoidance ... Read More

With a portion of up to 30–50% of total dissolved organic matter (DOM) in natural waters, fulvic acids can be considered the largest class of mobile organic carbon on the earth. Understanding fulvic acid properties and dynamics in aqueous solution would be substantial to understand DOM transport and dynamics. To date fulvic acids are only operationally defined by their sorption and ion-exchange properties towards certain polymeric sorbents that are used for their enrichment from aquatic samples. Owing to a lack of knowledge at ... Read More

Pharmaceuticals are ubiquitous contaminants occurring in the aquatic environment. Concentrations of human pharmaceuticals are typically highest in wastewaters but can also be relevant in surface waters, where, despite their low levels, they might give rise to undesirable effects on living organisms. A striking example of such very low dose effects has indeed been demonstrated very recently for a mixture of therapeutic drugs affecting the physiology and morphology of human embryonic cells. Since surface waters are often used as source for drinking-water production, ... Read More

The antiseptic effect of mercury(II)chloride (HgCl2) has been known since the 19th century and was widely applied by the wood preservation industry. The process of kyanizing, named after John Kyan who patented this process in England 1832, consists of steeping wood in a 0.66% HgCl2 preservative solution to prevent the wood from decay. On these wood impregnation sites, improper storage of treated wood or leakage of dip basins often led to a severe contamination of the environment, especially of soils and groundwater. ... Read More

The production of urban sludge is increasing on a global scale, firstly because more cities are connected to wastewater treatment plants and, secondly, because wastewater treatment performances have improved. Recycling of sludge as an organic fertilizer is environment friendly but among the huge diversity of micro-organisms found in urban wastewater, some pathogens can be present (viruses, bacteria and parasites) and such micro-organisms are concentrated in sludge during the treatment of wastewater. Furthermore, some of these pathogens are known to survive for several ... Read More

Due to their capability for disinfection (microorganisms) and oxidation (e.g. taste and odor control, elimination of micropollutants, etc.), chemical oxidants (i.e. ozone, chlorine, chlorine dioxide, chloramines, etc.) are commonly used in water treatment processes. However, under certain circumstances, oxidants can induce formation of potentially harmful by-products or transformation products due to their reactivity with water matrix components or micropollutants.Owing to its low cost, chlorine is globally the most used chemical oxidant for drinking water disinfection. Drinking water disinfection commonly involves the use ... Read More

Dissolved organic matter (DOM) in natural waters participates in many important ecological and geochemical reactions (Perdue and Gjessing, 1990; Kullberg et al., 1993; Hessen and Tranvik, 1998). For example, it controls the transport and fate of heavy metals, aluminium, radionuclides, and organic pollutants, initiates photoreactions, participates in particle surface and colloid chemistry, and affects ionic balance, including pH. Quantitative descriptions of these functional properties are needed for ecology, geochemistry, and to understand and predict the toxicity and fate of pollutants. The need ... Read More