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3× 108-1.0 × 109 Bq/d). Simulated results suggest that the massive influx of riverine particles and subsequent desorption of 137Cs increased dissolved 137Cs levels in the coastal seawater by an order of magnitude, from 3.3 mBq/L (pre-typhoon level) to 45-126 mBq/L. This found pathway opens up new scenarios involving radionuclide dynamics in the boundary area of river-sea system.Polyfluoroalkyl phosphoric acid diesters (diPAPs) have been widely and increasingly detected in various environmental mediums. The degradation of diPAPs brings perfluoroalkyl carboxylic acids (PFCAs) concerned of adverse health effects. DiPAPs mainly occur in particulate matter in ambient air and their photo-degradation behaviors have not been investigated. In this study, heterogeneous photo-degradation of 62 diPAP was studied on four model mineral components in ambient dust. 62 diPAP was found to undergo a fast degradation on titanium dioxide (TiO2) particles as well as on artificial mineral dust containing TiO2 (2.67% in mass) to produce C5-C7 PFCAs and other intermediates. Based on monitored intermediates and further degradation tests on important intermediates, thermodynamic calculation of energy barrier and Gibbs Free Energy was used to explain the observed degradation patterns and accordingly the degradation pathways of diPAPs were proposed. The increase in relative humidity promotes the production of hydroxyl radicals, which enhances the hydrolysis of 62 mono- and di-PAPs and the yield of C5 and C7 PFCAs. Oxygen is critical for radical formation, which bypasses the production of fluorotelomer carboxylic acid. Results of this study for the first time demonstrate that diPAP may account for additional PFCA sources in both indoor and outdoor environments and the heterogeneous degradation pathways were different from those of volatile fluorotelomer alcohols.The present study investigated the biodegradation of polystyrene (PS) plastic by mealworm (Tenebrio molitor) on different diets followed by untargeted screening of larvae gut intestine tissue and frass (manure and feed residuals) to investigate the existence of polymer-generated organic residues. Three different diets, consisting of PS, rolled barley and water were tested. PS degradation rates ranged from 16% to 23% within 15 days, with no statistical differences in survival rates. The larvae fed with ad libitum barleyPS (201 w/w) and water had the highest growth rate, while higher PS consumption was observed for barleyPS of 41 w/w. A GC-TOF-MS analysis revealed no contaminating substances in the gut intestine tissue, nor styrene or PS oligomers, whilst several bioactive compounds and traces of alkanes, mostly with small carbon chains, were present. Metabolomics analysis on the collected frass, either on the lipophilic (CHCl3) or the polar fraction (MeOH-H2O) was performed. Styrene and PS oligomers (dimers, trimers) were identified, though in a relatively low total amount, up to a total of 346.0 ng/mg 2,4 di-tert butylphenol was identified in both frass and tissue, coming from the PS polymer (Non-intentionally added substances; NIAS). Finally, in the polar fraction of frass, bioactive molecules (fatty acids, amides) were identified, together with several hydrocarbons, mostly with longer carbon chains. The formation of these substances indicated enzymatic and biochemical activity in the larvae-gut intestine. It was shown that degrading and contaminating organic compounds occur at low levels, in both gut intestine and frass, during bio-degradation of PS.The global energy crisis has stimulated the development of various forms of green energy technology such as microbial fuel cells (MFCs) that can be applied synergistically and simultaneously toward wastewater treatment and bioenergy generation. This is because electricigens in wastewater can act as catalysts for destroying organic pollutants to produce bioelectricity through bacterial metabolism. In this review, the factors affecting energy production are discussed to help optimize MFC processes with respect to design (e.g., single, double, stacked, up-flow, sediment, photosynthetic, and microbial electrolysis cells) and operational conditions/parameters (e.g., cell potential, microorganisms, substrate (in wastewater), pH, temperature, salinity, external resistance, and shear stress). The significance of electron transfer mechanisms and microbial metabolism is also described to pursue the maximum generation of power by MFCs. Technically, the generation of power by MFCs is still a significant challenge for real-world applications due to the difficulties in balancing between harvesting efficiency and upscaling of the system. This review summarizes various techniques used for MFC-based energy harvesting systems. This study aims to help narrow such gaps in their practical applications. Further, it is also expected to give insights into the upscaling of MFC technology while assisting environmental scientists to gain a better understanding on this energy harvesting approach.Soil flushing is one of the common in-situ remediation technologies, in which the permeability of the soil determines its feasibility. Batch extractions showed that deionized water extracted about 20% Cu and 30% Cd from a soil. Electrolytes of 100 mmol/l NaCl, 500 mmol/l NaCl, and 167 mmol/l CaCl2 promoted the extractions to about 60% and 90%, respectively, with higher concentration and valence of cations being more effective. see more Presence of 100 mmol/l EDTA as a chelant further enhanced the extractions to near completion. Extractions appeared to occur concurrently via ion exchange, complexation with Cl- and predominantly chelation with EDTA. Column leaching in dynamic setups with electrolyte solutions in the presence of EDTA showed similar Cu and Cd removal degrees to the batch extractions. The permeability of soils during leaching decreased by up to 80%, decelerating time-dependent Cu and Cd removal, due to soil swelling by Na+. Electrolytes in leaching solutions well defended the permeability of soil against its decrease to as low as 3.5%, maintaining Cu and Cd removal rates. Formulating flushing solution with EDTA and proper electrolytes have advantages of not only enhancing extraction degrees but accelerating heavy metal removal from soil by regulating the permeability, with the potential to be extended to soils with high clay contents and thus low natural permeability.