RESUMEN
The study investigated the dissipation ability of a vegetated free water surface (FWS) constructed wetland (CW) in treating pesticides-contaminated agricultural runoff/drainage water in a rural area belonging to Bologna province (Italy). The experiment simulated a 0.1% pesticide agricultural water runoff/drainage event from a 12.5-ha farm by dissolving acetamiprid, metalaxyl, S-metolachlor, and terbuthylazine in 1000 L of water and pumping it into the CW. Water and sediment samples from the CW were collected for 4 months at different time intervals to determine pesticide concentrations by multiresidue extraction and chromatography-mass spectrometry analyses. In parallel, no active compounds were detected in the CW sediments during the experimental period. Pesticides dissipation in the wetland water compartment was modeled according to best data practices by fitting the data to Single First Order (SFO), First Order Multi-Compartment (FOMC) and Double First Order in Parallel (DFOP) kinetic models. SFO (except for metalaxyl), FOMC and DFOP kinetic models adequately predicted the dissipation for the four investigated molecules, with the DFOP kinetic model that better fitted the observed data. The modeled distribution of each pesticide between biomass and water in the CW highly correlated with environmental indexes as Kow and bioconcentration factor. Computed DT50 by DFOP model were 2.169, 8.019, 1.551 and 2.047 days for acetamiprid, metalaxyl, S-metolachlor, and terbuthylazine, respectively. Although the exact degradation mechanisms of each pesticide require further study, the FWS CW was found to be effective in treating pesticides-contaminated agricultural runoff/drainage water within an acceptable time. Therefore, this technology proved to be a valuable tool for mitigating pesticides runoff occurring after intense rain events.
Asunto(s)
Acetamidas , Alanina/análogos & derivados , Neonicotinoides , Plaguicidas , Triazinas , Contaminantes Químicos del Agua , Humedales , Plaguicidas/análisis , Agricultura/métodos , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
The overuse of antimicrobials in livestock farming has led to the development of resistant bacteria and the spread of antibiotic-resistant genes (ARGs) among animals. When manure containing these antibiotics is applied to agricultural fields, it creates a selective pressure that promotes the acquisition of ARGs by bacteria, primarily through horizontal gene transfer. Most research on ARGs focuses on their role in clinical antibiotic resistance and their transfer from environmental sources to bacteria associated with humans, such as Escherichia coli. The study investigates the spread of antibiotic-resistant genes (ARGs) through class 1 integrons in 27 Escherichia coli strains from pig manure. It focuses on six common ARGs (ermB, cmlA, floR, qnrS, tetA, and TEM) and the class 1 integron gene, assessing their prevalence in manure samples from three pig farms. The study found correlations and anticorrelations among these genes, indicating a predisposition of the integron in spreading certain ARGs. Specifically, cmlA and tetA genes were positively correlated with each other and negatively with int1, suggesting they are not transferred via Int1. Farm B had the highest int1 counts and a higher abundance of the TEM gene, but lower levels of cmlA and tetA genes. The results underscore the complexity of predicting ARG spread in agricultural environments and the associated health risks to humans through the food chain. The study's results offer valuable insights into the antibiotic-resistant genes (ARGs) profile in swine livestock, potentially aiding in the development of methods to trace ARGs in the environment.
RESUMEN
This study focused on the application of mesoporous silica monoliths for the removal of organic pollutants. The physico-chemical textural and surface properties of the monoliths were investigated. The homogeneity of the textural properties along the entire length of the monoliths was assessed, as well as the reproducibility of the synthesis method. The adsorption properties of the monoliths for gaseous toluene, as a model of Volatile Organic Compounds (VOCs), were evaluated and compared to those of a reference meso-structured silica powder (MCM-41) of commercial origin. Silica monoliths adsorbed comparable amounts of toluene with respect to MCM-41, with better performances at low pressure. Finally, considering their potential application in water phase, the adsorption properties of monoliths toward Rhodamine B, selected as a model molecule of water soluble pollutants, were studied together with their stability in water. After 24 h of contact, the silica monoliths were able to adsorb up to the 70% of 1.5 × 10-2 mM Rhodamine B in water solution.
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Contaminantes Ambientales/aislamiento & purificación , Gases/química , Compuestos Orgánicos/aislamiento & purificación , Dióxido de Silicio/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Purificación del Agua/métodosRESUMEN
A pot experiment was carried out to evaluate the remediation potential of Brassica juncea and Sorghum bicolor in the decontamination of soil polluted with heavy metals such as copper, lead, tin, and zinc along with polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and heavy hydrocarbons. Two composts obtained from different composting processes were tested as biostimulating agents. At the end of the trial, the effect of plant/compost combinations on soil microbial composition, contaminant removal, biochemical indicators, and plant biomass production was determined. The results highlighted that compost addition improved plant biomass despite slowing down plants' removal of organic and inorganic contaminants. In addition, compost partially enhanced the soil biochemical indicators and modified the relative abundance of the rhizosphere microorganisms. Sorghum showed better mitigation performance than Brassica due to its higher growth. The soil fertility level, the choice of plant species, and microbial richness were found fundamental to perform soil remediation. In contrast, compost was relevant for a higher crop biomass yield.
Asunto(s)
Compostaje , Metales Pesados , Contaminantes del Suelo , Sorghum , Planta de la Mostaza , Descontaminación , Contaminantes del Suelo/análisis , Metales Pesados/análisis , SueloRESUMEN
The City Region Food Systems approach has been proposed to achieve food system resilience and nutrition security while promoting the urgent ecological transition within urban and peri-urban areas, especially after the COVID-19 pandemic. However, the great diversity of the initiatives composing City Region Food Systems in Europe poses barriers to the assessment of their integrated sustainability. Hence, the present work is developed within the EU-H2020 project Food System in European Cities (FoodE), to build a consistent sustainability scoring system that allows comparative evaluation of City Region Food System Initiatives. Adopting a Life Cycle Thinking approach, it advances on existing knowledge and past projects, taking advantage of a participatory process, with stakeholders from multidisciplinary expertise. As a result, the research designs, and tests on 100 case studies a simplified and ready-to-use scoring mechanism based on a quali-quantitative appraisal survey tool, delivering a final sustainability score on a 1-5 points scale, to get insights on the social, economic, and environmental impacts. As in line with the needs of the UN Sustainable Development Goals, the outcome represents a step forward for the sustainable development and social innovation of food communities in cities and regions, providing a practical and empirical lens for improved planning and governance.
RESUMEN
A non-waterproofed surface flow constructed wetland (SFCW), treating agricultural drainage water in Northern Italy, was investigated to gain information on the potential ability for effective pesticide abatement. A mixture of insecticide imidacloprid, fungicide dimethomorph, and herbicide glyphosate was applied, by simulating a single rain event, into 470-m-long water course of the SFCW meanders. The pesticides were monitored in the wetland water and soil for about 2 months after treatment. Even though the distribution of pesticides in the wetland was not uniform, for each of them, a mean dissipation of 50% of the applied amount was already observed at ≤7 days. The dissipation trend in the water phase of the wetland fitted (r2 ≥ 0.8166) the first-order model with calculated DT50 of 20.6, 12.0, 5.8, and 36.7 days for imidacloprid, dimethomorph, glyphosate, and the glyphosate metabolite AMPA, respectively. The pesticide behavior was interpreted based on the chemical and physical characteristics of both the substances and the water-soil system. Despite the fast abatement of glyphosate, traces were detected in the water until the end of the trial. The formation of soluble 1:1 complex between glyphosate and calcium, the most representative cation in the wetland water, was highlighted by infrared analyses. Such a soluble complex was supposed to keep traces of the herbicide in solution.
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Herbicidas , Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Granjas , Herbicidas/análisis , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , HumedalesRESUMEN
In this work, different mesoporous silicas were studied as potential sorbents for toluene, selected as a model molecule of aromatic organic fuel-based pollutants. Three siliceous materials with different textural and surface properties (i.e., fumed silica and mesoporous Santa Barbara Amorphous (SBA)-15 and Mobil Composition of matter (MCM)-41 materials) were considered and the effect of their physico-chemical properties on the toluene adsorption process was studied. In particular, FT-IR spectroscopy was used to qualitatively study the interactions between the toluene molecule and the surface of silicas, while volumetric adsorption analysis allowed the quantitative determination of the toluene adsorption capacity. The combined use of these techniques revealed that textural properties of the sorbents, primarily porosity, are the driving forces that control the adsorption process. Considering that, under real conditions of usage, the sorbents are soaked in water, their hydrothermal stability was also investigated and toluene adsorption by both the gas and aqueous phase on hydrothermally pre-treated samples was studied. The presence of ordered porosity, together with the different pore size distribution and the amount of silanol groups, strongly affected the adsorption process. In toluene adsorption from water, SBA-15 performed better than MCM-41.