Compared to antibiotic parent molecule, human metabolites are generally more polar and sometimes not less toxic in wastewater.However, most researches focus on the fate of parent molecule. Therefore, behaviors of human metabolites are little known.Moreover, though much has been done on the fate of antibiotics during activated sludge process, there are still some limitationsand gaps. In the present study, [Ring-14C] acetyl sulfamethoxazole (14C-Ac-SMX) was used to investigate the fate of humanmetabolite of SMX during activated sludge process at environmentally relevant concentration. At the end of 216 h, 3.1% of thespiked activity in the initial aqueous phase was mineralized, 50% was adsorbed onto the solid phase, and 36.5% still remained inthe aqueous phase, indicating that adsorption, not biodegradation, was the main dissipation pathway. In the existence of microbialactivities, accumulation into the solid phase was much higher, which was less bioavailable by chemical sequential extraction. Themultimedia kinetic model simultaneously depicted the fate of Ac-SMX in the gas, aqueous, and solid phases, and demonstratedthat microbially accelerated accumulation onto the solid phase was attributed to lower desorption rate from the solid phase to theaqueous phase, where adsorption rate was not the key factor. Therefore, Ac-SMX cannot be efficiently mineralized and remain inthe aqueous or the solid phases. The accumulation in the solid phase is less bioavailable and is hard to be desorbed in the existenceof microbial activities, and should not be easily degraded, and may lead to the development of antibiotic-resistant bacteria andgenes after discharge into the environment.

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Chlorpyrifos manufacturing wastewater (CMW) is characterized by complex composition, high chemical oxygen demand (COD) concentration, and toxicity. An integrated process comprising of peroxide (H2O2) promoted-catalytic wet air oxidation (PP-CWAO), struvite precipitation, and biological aerated filters (BAF) was constructed to treat CMW at a starting COD of 34000–35000 mg/L, total phosphorus (TP) of 5550–5620 mg/L, and total organophosphorus (TOP) of 4700–4840 mg/L. Firstly, PP-CWAO was used to decompose high concentrations of organic components and convert concentrated and recalcitrant TOP to inorganic phosphate. Copper citrate and ferrous citrate were used as the catalysts of PP-CWAO. Under the optimized conditions, 100% TOP was converted to inorganic phosphate with 95.6% COD removal. Then, the PP-CWAO effluent was subjected to struvite precipitation process for recovering phosphorus. At a molar ratio of Mg2+:NH4+:PO43− = 1.1:1.0:1.0, phosphate removal and recovery reached 97.2%. The effluent of struvite precipitation was further treated by the BAF system. Total removals of 99.0%, 95.2%, 97.3%, 100%, and 98.3% were obtained for COD, total suspended solids, TP, TOP, and chroma, respectively. This hybrid process has proved to be an efficient approach for organophosphate pesticide wastewater treatment and phosphorus reclamation.

International audience

International audience | At the global scale, urban agriculture is increasingly developing in cities due to demographic growth and sustainable food concerns. But, urban soils are frequently polluted with metals. In urban gardens, organic matter is also commonly added both to valorize organic household waste and to promote biophysicochemical fertility. As earthworms promote the decomposition and the recycling of soil organic matter, they can also influence the biogeochemical cycle of metals in urban polluted soils. In order to produce safe vegetables in urban areas, it is crucial to highlight the mechanisms involved in complex soil-earthworm-plant ecosystems. An experiment was set up to examine these relationships using lettuce cultivated in controlled conditions with RHIZOtest® devices. Thanks to the RHIZOtest® devices, metal transfer and bioaccessibility were for the first time compared for urban polluted soil without (1-urban soil polluted with Pb, Cd, Cu, and Zn: essential or toxic metals currently found in environment, SNB) and with bioturbation (2-this metal-polluted soil subjected to earthworm bioturbation, SB) and earthworm casts (3-earthworm casts produced in this polluted soil and naturally enriched in organic matter and microorganisms, T). Metal concentration, phytoavailability, and human gastric bioaccessibility were determined in the different samples. Results showed that earthworm bioturbation increased the phytoavailability of all the metals. For the experimental condition SB, the phytoavailability of metals was increased up to 75% compared to SNB. In addition, surprisingly, metal phytoavailability was always superior in SB compared to earthworm casts (T). Moreover, earthworms led to an increase in Zn gastric bioaccessibility up to 10% in the soils in the same way as for phytoavailability, meaning Zn bioaccessibility in SB > T > SNB, whereas it remained unchanged in the lettuces. These data are important to promote sustainable agriculture activities in urban areas; actually, databases concerning different experimental conditions are needed to develop decision support tools.

International audience | At the global scale, urban agriculture is increasingly developing in cities due to demographic growth and sustainable food concerns. But, urban soils are frequently polluted with metals. In urban gardens, organic matter is also commonly added both to valorize organic household waste and to promote biophysicochemical fertility. As earthworms promote the decomposition and the recycling of soil organic matter, they can also influence the biogeochemical cycle of metals in urban polluted soils. In order to produce safe vegetables in urban areas, it is crucial to highlight the mechanisms involved in complex soil-earthworm-plant ecosystems. An experiment was set up to examine these relationships using lettuce cultivated in controlled conditions with RHIZOtest® devices. Thanks to the RHIZOtest® devices, metal transfer and bioaccessibility were for the first time compared for urban polluted soil without (1-urban soil polluted with Pb, Cd, Cu, and Zn: essential or toxic metals currently found in environment, SNB) and with bioturbation (2-this metal-polluted soil subjected to earthworm bioturbation, SB) and earthworm casts (3-earthworm casts produced in this polluted soil and naturally enriched in organic matter and microorganisms, T). Metal concentration, phytoavailability, and human gastric bioaccessibility were determined in the different samples. Results showed that earthworm bioturbation increased the phytoavailability of all the metals. For the experimental condition SB, the phytoavailability of metals was increased up to 75% compared to SNB. In addition, surprisingly, metal phytoavailability was always superior in SB compared to earthworm casts (T). Moreover, earthworms led to an increase in Zn gastric bioaccessibility up to 10% in the soils in the same way as for phytoavailability, meaning Zn bioaccessibility in SB > T > SNB, whereas it remained unchanged in the lettuces. These data are important to promote sustainable agriculture activities in urban areas; actually, databases concerning different experimental conditions are needed to develop decision support tools.

International audience

International audience | Pyrolysis of waste materials to produce biochar is an excellent and suitable alternative supporting a circular bio-based economy. One of the properties attributed to biochar is the capacity for sorbing organic contaminants, which is determined by its composition and physicochemical characteristics. In this study, the capacity of waste-derived biochar to retain volatile fuel organic compounds (benzene, toluene, ethylbenzene and xylene (BTEX) and fuel oxygenates (FO)) from artificially contaminated water was assessed using batch-based sorption experiments. Additionally, the sorption isotherms were established. The results showed significant differences between BTEX and FO sorption on biochar, being the most hydrophobic and non-polar contaminants those showing the highest retention. Furthermore, the sorption process reflected a multilayer behaviour and a relatively high sorption capacity of the biochar materials. Langmuir and Freundlich models were adequate to describe the experimental results and to detect general differences in the sorption behaviour of volatile fuel organic compounds. It was also observed that the feedstock material and biochar pyrolysis conditions had a significant influence in the sorption process. The highest sorption capacity was found in biochars produced at high temperature (> 400 °C) and thus rich in aromatic C, such as eucalyptus and corn cob biochars. Overall, waste-derived biochar offers a viable alternative to be used in the remediation of volatile fuel organic compounds from water due to its high sorption capacity.

International audience | Improving water management depends on understanding the functioning of irrigation and drainage systems across different environmental scales. For this purpose, this study in the Nile Delta of Egypt particularly examines the spatial and temporal variation of drainage water salinity from the system to the plot level. A better understanding of this variation across nested scales is crucial to refine the government's drainage reuse strategy and reduce the adverse effects on agricultural productivity, lagoon ecology, and human health. The study investigates the drainage system of the Meet Yazid study area (82,740 ha) located in the upper central part of the Nile Delta. The parameters measured were electrical conductivity (EC), dissolved oxygen (DO), pH, and temperature. Results showed that salinity and quality of drainage water in the Nile Delta vary highly with space and time. The secondary drains exhibited the highest variability of salinity compared with main drains and subsurface drainage collectors because they accumulate salts from deeper soil layers and seepage of saline groundwater at the time of low flow discharge. In secondary drains, the salinity increased up to four times that of drainage water coming from the collectors. Moreover, DO values were most of the time not meeting standards for reuse in irrigation, especially at main drains that collect not only agricultural drainage but also untreated household sewage water.

International audience | Pollution from bromine and some of its related compounds is currently unregulated in soil from Russia and other countries,and tools for sound assessment of environmental impacts of bromine contamination are largely missing. Hence, assessingpotential implications for humans and ecosystems of bromine soil contamination is urgently needed, which requires the combi-nation of measured soil concentrations from environmental studies and quantified potential toxicity impacts. To address this need,we used data from an experimental study assessing bromine in soils (384 samples) of Tomsk oblast, Russia, starting frommeasured concentrations obtained by Instrumental Neutron Activation Analysis in an earlier study. From these data, we calcu-lated the bromine mass in soils and used these as starting point to characterize related cumulative impacts on human health andecosystems in the Tomsk region, using a global scientific consensus model for screening-level comparative toxicity character-ization of chemical emissions. Results show that the combination of sampling methodology with toxicity characterizationtechniques presents a new approach to be used in environmental studies aimed at environmental assessment and analysis of aterritory. Our results indicate that it is important to account for substance-specific chemical reaction pathways and transferprocesses, as well as to consider region-specific environmental characteristics. Our approach will help complement environmen-tal assessment results with environmental sustainability elements, to consider potential tradeoffs in impacts, related to soilpollution, in support of improved emission and pollution reduction strategies.