Fluorochemicals have widespread applications and are released into municipal wastewater treatment plants via domestic wastewater. A field study was conducted at a full-scale municipal wastewater treatment plant to determine the mass flows of selected fluorochemicals. Flow-proportional, 24 h samples of raw influent, primary effluent, trickling filter effluent, secondary effluent, and final effluent and grab samples of primary, thickened, activated, and anaerobically digested sludge were collected over 10 days and analyzed by liquid chromatography electrospray-ionization tandem mass spectrometry. Significant decreases in the mass flows of perfluorohexane sulfonate and perfluorodecanoate occurred during trickling filtration and primary clarification, while activated sludge treatment decreased the mass flow of perfluorohexanoate. Mass flows of the 6:2 fluorotelomer sulfonate and perfluorooctanoate were unchanged as a result of wastewater treatment, which indicates that conventional wastewater treatment is not effective for removal of these compounds. A net increase in the mass flows for perfluorooctane and perfluorodecane sulfonates occurred from trickling filtration and activated sludge treatment. Mass flows for perfluoroalkylsulfonamides and perfluorononanoate also increased during activated sludge treatment and are attributed to degradation of precursor molecules.
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http://dx.doi.org/10.1021/es061025m | DOI Listing |
Biomimetics (Basel)
December 2024
Department of Mechanical Engineering, San Diego State University, San Diego, CA 92182, USA.
Collecting fog water is crucial for dry areas since natural moisture and fog are significant sources of freshwater. Sustainable and energy-efficient water collection systems can take a page out of the cactus's playbook by mimicking its native fog gathering process. Inspired by the unique geometric structure of the cactus spine, we fabricated a bioinspired artificial fog collector consisting of cactus spines featuring barbs of different sizes and angles on the surfaces for water collection and a series of microcavities within microchannels inspired by Nepenthes Alata on the bottom to facilitate water flowing to the reservoir.
View Article and Find Full Text PDFMaterial flow analysis (MFA) is used to quantify and understand the life cycles of materials from production to end of use, which enables environmental, social, and economic impacts and interventions. MFA is challenging as available data are often limited and uncertain, leading to an under-determined system with an infinite number of possible stocks and flows values. Bayesian statistics is an effective way to address these challenges by principally incorporating domain knowledge, quantifying uncertainty in the data, and providing probabilities associated with model solutions.
View Article and Find Full Text PDFHuan Jing Ke Xue
January 2025
School of Civil Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China.
To explore the source information and composition characteristics of dissolved organic matter (DOM) in different regions of water bodies in northern cities, considering the urban water system of Shijiazhuang, Hebei Province as an example, ultraviolet-visible spectroscopy (UV-vis) and three-dimensional fluorescence parallel factor analysis (EEM-PARAFAC) were used to explain the optical parameters, abundance, and proportion of different components of DOM in water bodies of different regions. The results showed that: ① The concentrations of NO-N, NO-N, NH-N, TN, TP, and COD in the upstream were significantly lower than those in urban water bodies and downstream (<0.01), and TSI increased after the water entered the city.
View Article and Find Full Text PDFEnviron Pollut
December 2024
School of Environmental Studies, China University of Geosciences, Wuhan 430078, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430078, China.
Polycyclic aromatic hydrocarbons (PAHs) are a class of organic pollutants widely present in various environmental media. Some PAHs have carcinogenic, teratogenic, and mutagenic effects. Urban lakes are severely polluted by PAHs due to human activities.
View Article and Find Full Text PDFKyobu Geka
November 2024
Department of Thoracic Surgery, Sendai Kousei Hospital, Sendai, Japan.
A 58-year-old woman was pointed out an abnormal electrocardiogram during a physical examination. A chest computed tomography( CT) scan revealed a 50-mm-sized cystic mass in the posterior mediastinum near the tracheal bifurcation. The mass exhibited growth during follow-up imaging, leading to a surgical resection.
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