The occurrence, concentrations, patterns, and loads of 17 2,3,7,8-substituted congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in treated wastewater collected at the outlets from 14 wastewater treatment plants (WTPs), divided into three size categories. The analysis also considered the effect of wastewater outflow on the final concentrations of PCDDs/Fs, as the samples were collected during flooding and stable hydrological conditions. None of the studied WTPs were found to completely remove toxic congeners of PCDDs/Fs from wastewater: the PCDD concentrations in the outgoing effluent during stable wastewater flow ranged from 2.99 to 177.19 pg/L, PCDFs from 6.05 to 51.30 pg/L, and the Toxic Equivalent (TEQ) was between 0.94 and 4.87 pg/L. The results from high wastewater flow were less diversified, ranging from 5.04 to 8.85 pg/L for PCDDs, from 11.47 to 32.33 pg/L for PCDFs and from 2.00 to 4.65 pg/L for TEQ. The smallest WTPs demonstrated the highest average total and TEQ concentrations due to limited volume, short retention time and outdated technology, and, hence, insufficient treatment efficiency. The largest WTPs have the potential to substantially affect the quality of river water, as despite being associated with the lowest concentrations, they released much greater volumes of treated wastewater and, hence, the greatest amounts of analyzed compounds. Elevated TEQ values were observed at high flow in all WTP size categories indicating the impact of high and stable wastewater flow on the concentrations of the observed PCDDs/Fs.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5285434 | PMC |
http://dx.doi.org/10.1007/s10661-017-5794-9 | DOI Listing |
J Environ Manage
January 2025
Department of Civil, Environmental and Architectural Engineering, University of Padova, Via Marzolo 9, 35131, Padova, Italy.
The materials removed in the oil separation units of wastewater treatment plants can be referred to as fat, oil and grease (FOG) waste. FOG waste accumulation in treatment plants can cause clogging of pipes, production of excessive scums and foams, and negatively affect air/liquid oxygen transfer. While conventional disposal routes of this material can be limited by its water and organic content, FOG can represent a source of bio-energy other than bio-diesel production.
View Article and Find Full Text PDFTrends Biotechnol
January 2025
School of Civil and Environmental Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia. Electronic address:
The dissemination of antibiotic resistance from environmental sources is a growing concern. Despite the widespread occurrence of antibiotic resistance transmission events, there are actually multiple obstacles in the ecosystem that restrict the flow of bacteria and genes, in particular nonnegligible biological barriers. How these ecological factors help combat the dissemination of antibiotic resistance and relevant antibiotic resistance-diminishing organisms (ARDOs) deserves further exploration.
View Article and Find Full Text PDFJ Environ Sci (China)
July 2025
John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, New Jersey 07102, USA.
In this study, synthetic wastewater containing 110 µg/L arsenate (As(V)), 0-20 mg/L fulvic acid (FA), and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe. The mechanisms of FA and phosphate effects on As(V) removal by ferric chloride were determined using 0.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Sanitary Engineering Laboratory, Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, 9 Iroon Polytechniou St., Zographou Campus, 15773, Athens, Greece.
Vertical subsurface flow constructed wetlands (VSSF CWs) were employed to investigate the use of biochar that could be produced with local agricultural biomass through pyrolysis, recycled glass from local recycling companies and gel beads with decreased packing volume and shipping cost as substrate alternatives to sand. The materials were assessed in terms of granulometry, porosity, adsorption capacity and hydraulic conductivity and were used for the treatment of an upflow anaerobic sludge blanket (UASB) reactor, treating domestic wastewater, effluent. Granulometry was a major factor impacting TSS removal that ranged from 81% ± 10% to 97% ± 2%.
View Article and Find Full Text PDFWater Res
January 2025
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:
The flow through the grit chamber is non-biochemically treated wastewater, which contains microorganisms mainly from the source of wastewater generation. There are limited reports on aerosol particles generated by grit chambers compared with those produced by biochemical treatment tanks. This study analyzed the fugitive characteristics of aerosol particles produced in grit chambers at nine wastewater treatment plants in three regions of China.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!