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Understanding nanomaterial transformations within wastewater treatment plants is an important step to better predict their potential impact on the environment. Here, spatially resolved, in situ nano‐X‐ray fluorescence microscopy is applied to directly observe nanometer‐scale dissolution, morphological, and chemical evolution of individual and aggregated ZnO nanorods in complex "real‐world" conditions: influent water and primary sludge collected from a municipal wastewater system. A complete transformation of isolated ZnO nanorods into ZnS occurs after only 1 hour in influent water, but larger aggregates of the ZnO nanorods transform only partially, with small contributions of ZnS and Zn‐phosphate (Zn3(PO4)2) species, after 3 hours. Transformation of aggregates of the ZnO nanorods toward mixed ZnS, Zn adsorbed to Fe‐oxyhydroxides, and a large contribution of Zn3(PO4)2 phases are observed during their incubation in primary sludge for 3 hours. Discrete, isolated ZnO regions are imaged with unprecedented spatial resolution, revealing their incipient transformation toward Zn3(PO4)2. Passivation by transformation(s) into mixtures of less soluble phases may influence the subsequent bioreactivity of these nanomaterials. This work emphasizes the importance of imaging the nanoscale chemistry of mixtures of nanoparticles in highly complex, heterogeneous semi‐solid matrices for improved prediction of their impacts on treatment processes, and potential environmental toxicity following release. [ABSTRACT FROM AUTHOR]

Exposure to micropollutants can pose a serious risk to both the environment and human health. Although sewage treatment works (STWs) aim to reduce levels of pollutants in municipal wastewater discharges, they have become a significant point source of dangerous substances to the aquatic environment. With increasing regulation on pollution prevention, it has become essential to assess STW source inputs in order to control pollutant discharge into the environment. This paper has therefore focussed on developing calculations to estimate micropollutant levels in STW influents. The analysis was carried out using information from published literature, the Water Industry, and monitored influent data. Results demonstrated that, where monitoring data were available for metals and organic pollutants, STW influent could be adequately estimated and validated, with accuracy between 77% and 100%. In addition, based on these calculations and using data for over 600 STWs in England, our analysis showed that compounds such as di(2-ethylhexyl) phthalate, lead and linear alkylbenzenesulfonate could reach influent levels that could be challenging for conventional wastewater treatment removal. [ABSTRACT FROM AUTHOR]

Abstract: Predicted environmental concentrations for five commonly used pharmaceuticals were calculated using data from the UK Department of Health according to risk assessment guidelines proposed by the European Agency for the Evaluation of Medicinal Products. Surface waters from the South–East of England were analysed and results were compared with predicted concentrations and findings from other studies from the UK and Europe. It was found that the efficacy of these predictions varied and was hampered by a shortage of data for many of the drugs. Ibuprofen, paracetamol and salbutamol were detected and quantified in all locations sampled. Ibuprofen was consistently found at the highest concentrations (up to 3μgl−1). Levels up and downstream of two wastewater treatment works were compared in order to investigate the link between sewage discharge and environmental concentrations of pharmaceuticals. Results from one site demonstrated a considerable increase in concentrations of ibuprofen, salbutamol and paracetamol downstream from the treatment works; however, no link was established for a second works. [Copyright &y& Elsevier]

Pollution from endocrine disrupting compounds and related micropollutants is widely regarded as a major environmental issue on both a regional and a global scale, largely due to concerns over risks to human and ecological health. Between 2005 and 2010, the United Kingdom is conducting a demonstration program, costing ~40 million (~$80 million at the time of writing), to evaluate technologies to remove these compounds from wastewater. However, while such advanced treatment techniques will undoubtedly reduce the discharges of micropollutants, they will also inevitably result in large financial costs, as well as environmentally undesirable increases in energy consumption and CO2 emissions. Here we calculate the price of treating urban sewage with two of the major options specifically proposed in the U.K. demonstration program: (i) granular activated carbon and ozone and (ii) membrane filtration and reverse osmosis. Economic analysis indicates that treating wastewater with these advanced technologies may be economically and environmentally undesirable due to the increased energy consumption and associated economic costs and CO2 emissions. Since the costs of advanced treatment of sewage would most likely have to be passed on to customers (both domestic and industrial), we propose that national demonstration programs should not only compare and contrast the most advanced treatment methods but also consider alternative techniques, such as increased sludge ages and hydraulic retention times in conjunction with nutrient removal stages and the varying redox conditions associated with them, which potentially may be almost as effective but with much lower environmental and financial costs. [ABSTRACT FROM AUTHOR]