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Exploring alternative fertilizers is crucial in agriculture due to the cost and environmental impact of inorganic options. This study investigated the potential of sewage-derived biofertilizers on the growth and physiology of Amaranthus cruentus plants. Various treatments were compared, including control treatments with inorganic fertilizer and treatments with biofertilizers composed of microalgae, biosolids and reclaimed water. The following traits were investigated: photosynthetic pigments, gas exchange, growth, and leaf nutrient concentrations. The results showed that the concentrations of N, P, Cu, Fe Zn and Na nutrients, in the dry microalgae and biosolids, were quite high for the needs of the plants. The wet microalgae presented high concentration of Cu, Fe and Zn nutrients while reclaimed water contained high concentration of N, K, Ca and S. Na and Zn nutrients increased in the leaf of plants treated with dry microalgae and biosolid, respectively. At the beginning of the flowering phase, total chlorophyll and carotenoids contents were lower for plants grown with wet microalgae while for plants grown with higher doses of biosolid or reclaimed water total chlorophyll was increased, and carotenoids were not affected. Lower photosynthetic pigments under wet microalgae resulted in lower photosynthetic rates. On the other hand, amendments with dry microalgae and biosolid increased photosynthetic rates with the biosolid being the most effective. Higher applications of biosolid, wet and dry microalgae produced a considerable increase in shoot biomass of amaranth, with the dry microalgae being the most effective. Additionally, reclaimed water obtained after tertiary treatment of sewage with microalgae and biosolids applied alone showed promising effects on plant growth. Overall, these findings suggest that organic fertilizers derived from sewage treatment have the potential to enhance plant growth and contribute to sustainable agricultural practices.

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Wastewaters are nutrient-rich organic materials containing significant concentrations of different nutrients, dissolved and particulate matter, microorganisms, solids, heavy metals, and organic pollutants, including aromatic xenobiotics. This variety makes wastewater treatment a technological challenge. As a result of wastewater treatment, biosolids are generated. Biosolids, commonly called sewage sludge, result from treating and processing wastewater residuals. Increased biosolids, or activated sludge, from wastewater treatment is a major environmental and social problem. Therefore, sustainable and energy-efficient wastewater treatment systems must address the water crisis and environmental deterioration. Although research on wastewater has received increasing attention worldwide, the significance of biosolids treatments and valorization is still poorly understood in terms of obtaining value-added products. Hence, in this review, we established some leading technologies (physical, chemical, and biological) for biosolids pretreatment. Later, the research focuses on natural treatment by fungal enzymes to end with lignocellulosic materials and xenobiotic compounds (polyaromatic hydrocarbons) as a carbon source to obtain biobased chemicals. Finally, this review discussed some recent trends and promising renewable resources within the biorefinery approach for bio-waste conversion to value-added by-products.

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Biosolids have been long used as a soil amendment to promote nutrient recovery. The readily releasable forms of nutrients present in this biowaste, such as phosphorus (P), along with their over application, can be detrimental to the environment, causing eutrophication. Pyrolysis, the thermal decomposition of organic materials at elevated temperature and low oxygen, seems to be a promising strategy to lower P release from biowastes such as biosolids. We pyrolyzed biosolids from various treatments and locations (Florida and Illinois; Galicia, Spain; and São Paulo, Brazil) to convert to biochar. Our objectives were (a) to use solid-state assessments, such as X-ray diffraction and scanning electron microscopy, and chemical assessments, such as water-soluble P (WSP), pH, Mehlich 3-extractable P (M3-P), total P (TP), and total Kjeldahl nitrogen, to evaluate changes caused by the conversion and (b) to compare P leaching potentials of biosolids and their corresponding biochars on two soils with varying P retention capacities. Pairwise comparisons indicated that biochar conversion significantly increased TP in the final material, but the absolute WSP decreased. However, M3-P remained the same after conversion to biochar. Cumulative P leached as a fraction of TP was greater for biosolids than their corresponding biochars. Two soils with contrasting P retention capacities predictably differed in P leaching behaviors as amended with biosolids and biochars. Differences suggest that future research could evaluate the efficacy of using mixtures of biosolids and biochar for a given soil to maintain soil fertility while reducing environmental P loss risk.

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Primary sludge (PS) is associated with public health and environmental risks, so regulations focus on reducing the pathogenic and heavy metal contents of the treated material (biosolids), intended for soil amendments and land reclamation. The regulations set limits for Escherichia coli (or fecal coliforms), Salmonella spp., helminth eggs and enterovirus. However, the potential risk due to antibiotic resistant bacteria (ARB) and other human potential pathogenic bacteria (HPB) are not considered. In this work, three sludge treatment processes, having in common an anaerobic digestion step, were applied to assess the removal of regulated bacteria (fecal coliforms, Salmonella spp), ARB and HPB. The treatment arrangements, fed with PS from a full-scale wastewater treatment plant were: 1) Mesophilic anaerobic digestion followed by alkaline stabilization post-treatment (MAD-CaO); 2) Thermophilic anaerobic digestion (TAD) and, 3) Pre-treatment (mild thermo-hydrolysis) followed by TAD (PT-TAD). The results address the identification, quantification (colony forming units) and taxonomic characterization of ARB resistant to ß-lactams and vancomycin, as well as the taxonomic characterization of HPB by sequencing with PacBio. In addition, quantification based on culture media of fecal coliforms and Salmonella spp. is presented. The capabilities and limitations of microbiological and metataxonomomic analyses based on PacBio sequencing are discussed, emphasizing that they complement each other. Genus Aeromonas, Acinetobacter, Citrobacter, Enterobacter, Escherichia, Klebsiella, Ochrobactrum, Pseudomonas and Raoultella, among others, were found in the PS, which are of clinical or environmental importance, being either HPB, HPB-ARB, or non-pathogenic ARB with the potentiality of horizontal gene transfer. Based on the analysis of fecal coliforms and Salmonella spp., the three processes produced class A (highest) biosolids, suitable for unrestricted agriculture applications. Mild thermo-hydrolisis was effective in decreasing ARB cultivability, but it reappeared after the following TAD. O. intermedium (HPB-ARB) was enriched in MAD and TAD while Laribacter hongkongensis (HPB) did persist after the applied treatments.

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Composting and vermicomposting are an environmentally friendly way to reduce pathogens in organic wastes and generate a valuable product that provides nutrients for crops. However, how the bacterial community structure changes during these different processes and if the bacteria applied with the (vermi)composted products survive in an arable cultivated soil is still largely unknown. In this study, we monitored how the bacterial community structure changed during conditioning, composting with and without Eisenia fetida, and when the end-product was applied to arable soil cultivated with wheat Triticum sp. L. The organic wastes used were biosolid, cow manure, and a mixture of both. Large changes occurred in the relative abundance of some of the most abundant bacterial genera during conditioning, but the changes were much smaller during composting or vermicomposting. The bacterial community structure was significantly different in the organic wastes during conditioning and (vermi)composting but adding E. fetida had no significant effect on it. Changes in the relative abundance of the bacterial groups in the (vermi)composted waste applied to the arable soil cultivated with wheat were small, suggesting that most survived even after 140 days. As such, applying (vermi)composted organic wastes not only adds nutrients to a crop but also contributes to the survival of plant growth-promoting bacteria found in the (vermi)compost. However, putative human pathogens found in the biosolid also survived in the arable soil, and their relative abundance remained high but mixing the biosolid with cow manure reduced that risk. It was found that applying (vermi)composted organic wastes to an arable soil not only provides plant nutrients and adds bacteria with plant growth-promoting capacities, but some putative pathogens also survived.

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Biosolids are a by-product of wastewater treatment, and their nutritional composition makes them ideal for fertilizing crops. However, pre-treatments, such as conditioning and/or (vermi)composting, are often required to stabilize the product and remove pathogens. Biosolids, cow manure, and a 50-50% mixture were conditioned for 21 days, composted or vermicomposted with Eisenia fetida (Savigny 1826) for 28 days, and applied to soil cultivated with wheat (Triticum sp. L.), while emissions of nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) were monitored. Emissions of CH4 were large from the biosolid and N2O from the cow manure during conditioning. Emissions of CH4 remained high during (vermi)composting of the biosolids, while the emissions of N2O from the cow manure dropped. The addition of E. fetida did not affect the emissions of greenhouse gases during (vermi)composting. The emission of N2O was higher when (vermi)composted biosolid was applied to soil cultivated with wheat than when (vermi)composted cow manure was applied. The global warming potential (GWP) of the sum of the emitted greenhouse gases (GHG) during conditioning, (vermi)composting, and when the final product was applied to soil was 3 times larger from the cow manure than from the biosolid, but mixing biosolid with cow manure eliminated that difference. It was concluded that mixing biosolid with cow manure might be a simple way to reduce the GWP of the emitted GHG during storage, (vermi)composting, and when applied to soil.

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O comportamento e o destino dos fármacos e seus metabólitos no meio aquático, assim como seus efeitos na biota e saúde humana, têm sido objeto de estudos em âmbito global. No entanto, poucas pesquisas relacionam parâmetros operacionais e físico-químicos à remoção dos fármacos em Estações de Tratamento de Esgotos (ETE). Os principais processos responsáveis pela redução da concentração destes contaminantes na fase aquosa, durante o tratamento de esgotos, são a biodegradação e a sorção à fase sólida. No que diz respeito à qualidade dos lodos produzidos, um aspecto ainda pouco estudado refere-se à identificação de poluentes emergentes, substâncias presentes no ambiente e que usualmente não são monitoradas, especialmente pela ausência de regulamentação legal nos países, podendo apresentar risco potencial à saúde humana e ao meio ambiente. Desse modo, o presente estudo tem por objetivo identificar, quantificar e avaliar a eficiência de remoção de fármacos presentes em biossólidos provenientes de uma ETE, antes e após o processo de compostagem, utilizando técnicas de cromatografia UFLCTM e espectrometria MS-MS, e avaliar os fármacos escolhidos para estudo, com base no modelo QSAR (ECOSAR-EPA), visando identificar o potencial de bioacumulação e ecotoxicidade dessas substâncias no ambiente, de acordo com as propriedades físico-químicas. De acordo com os resultados obtidos observa-se que houve redução na concentração dos compostos avaliados, indicando tendência à biodegradação ou redução na biodisposição dos mesmos. O processo de compostagem estudado, além de mostrar-se adequado para a produção de um biossólido com características compatíveis com as requeridas para o uso agrícola, possibilitou constatar a eficiência do processo como alternativa para o tratamento desses contaminantes presentes no lodo de esgotos. Possíveis interações que possam ocorrer com outros fármacos presentes no ambiente, em relação a concentrações residuais e metabólitos gerados, os quais não foram investigados no presente estudo, apontam para a necessidade de estudos em relação aos mecanismos farmacocinéticos e farmacodinâmicos para entendimento dos mecanismos de reação envolvidos na formação e toxicidade de seus metabólitos. A presença destes compostos nas várias matrizes ambientais denota a importância das pesquisas nessa área, e a adoção de boas práticas operacionais visando garantir a qualidade e a segurança requeridas na utilização benéfica do lodo de esgotos, principalmente para fins agrícolas.

The behavior and fate of drugs and their metabolites in the aquatic environment, as well as their effects on biota and human health, have been the object of studies on a global scale. However, few research relate operational and physicochemical parameters to the removal of drugs in Sewage Treatment Plants (ETE). The main processes responsible for reducing the concentration of these contaminants in the aqueous phase, during sewage treatment, are biodegradation and sorption to the solid phase. Regarding the quality of the sludge produced, an aspect that has still been poorly studied refers to the identification of emerging pollutants, substances present in the environment that are usually not monitored, especially due to the lack of legal regulations in the countries, which may present a potential risk to health. human and the environment. Thus, this study aims to identify, quantify, and evaluate the efficiency of removal of drugs present in biosolids from an ETE, before and after the composting process, using UFLCTM chromatography and MS-MS spectrometry techniques, and evaluate the drugs chosen for study, based on the QSAR model (ECOSAR-EPA), to identify the bioaccumulation potential and ecotoxicity of these substances in the environment, according to their physicochemical properties. According to the results obtained, it is observed that there was a reduction in the concentration of the compounds evaluated, indicating a tendency to biodegradation or a reduction in their biodisposition. The composting process studied, in addition to being suitable to produce biosolids with characteristics compatible with those required for agricultural use, made it possible to verify the efficiency of the process as an alternative for the treatment of these contaminants present in sewage sludge. Possible interactions that may occur with other drugs present in the environment, in relation to residual concentrations and generated metabolites, which were not investigated in this study, point to the need for studies in relation to pharmacokinetic and pharmacodynamic mechanisms to understand the reaction mechanisms involved in the formation and toxicity of its metabolites. The presence of these compounds in the various environmental matrices denotes the importance of research in this area, and the adoption of good operational practices to ensure the quality and safety required in the beneficial use of sewage sludge, mainly for agricultural purposes.

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Optimization of the use of water and the possibility of using residues as substrate in the black pepper production chain can yield economic and environmental benefits. The objective of this study was to evaluate the biometric and physiological traits of black pepper plantlets (Piper nigrum L.), cv. Bragantina, at different irrigation levels and soilless substrates. Plantlets were grown for 120 days on three substrates [biosolid + crushed coconut fiber (3:1, by volume); biosolid + granitic rock powder (3:1, by volume); and biosolid + crushed coconut fiber + granitic rock powder (2:1:1, by volume)] and at five irrigation levels [36 % (very low); 55 % (low); 85 % (moderate); 100 % (well-irrigated); and 126 % of the reference irrigation level (over-irrigated)]. The biometric traits evaluated increased as the irrigation levels increased, with the exception of root dry mass, which was not influenced by this factor, nor water use efficiency, which decreased as the irrigation levels increased. In general, plants grown with a mixture of the three wastes (biosolid + crushed coconut fiber + granitic rock powder) exhibited higher values for biometric variables and chlorophyll content when they were moderately, well or over-irrigated, in comparison with the other two substrates. It was possible to achieve the plantlet commercial standard using this three waste mixture and the moderate irrigation level.(AU)

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The dependence of mineral fertilizers, increasingly, has brought concern facing the increased demand and because it is a non-renewable mineral resource. The organic fertilization, exclusively, it is impractical in large scale, however, the combination of organic and mineral sources have already proved to be feasible, both from the point of view of nutrition of plants as well as in the aspect of recycling of urban and industrial waste by agriculture. This research had as objective to determine the efficiency of aorganomineral fertilizer formulated on the basis of sewage sludge in substitution of mineral fertilizer in the cultivation of sugar cane in environments with different levels of soil fertility. An experiment was conducted in greater soil fertility, in the Institute Federal Goiano­Campus, Morrinhos-GO, Brazil. The other, less soil fertility, was implanted in the ethanol industry Tijuco Valley, located in Rio do Peixe, district of Prata-MG, Brazil. The experimental design was randomized blocks in a factorial 5 x 2 +1 being five doses, with and without a biostimulant plus an additional with mineral fertilization, in four replications. The doses werein function of fertilization recommendation of planting and coverage for each environment, consisting of: 100 % of the mineral source and percentage 0; 60; 80; 100 and 120 % of organomineral fertilizer. We evaluated the productivity, tillering, diameter and height of stem in Prata-MG the different percentages of the fertilization of planting favored and increased productivity, height and stem diameter of sugar cane; the use of biostimulants not contributed to increase crop yield. In Morrinhos-GO, the different percentage of planting fertilization did not increase the productivity, tillering, height and diameter of the sugarcane stem; the use of biostimulants increases the productivity yield of sugarcane. Organomineral fertilizer based on biosolids is similar to fertilization with mineral fertilizer in environments

A dependência de fertilizantes minerais, cada vez mais, trouxe preocupação frente ao aumento da demanda e por ser um recurso mineral não renovável. A adubação orgânica, em exclusivo, é impraticável em larga escala, no entanto, a combinação de fontes orgânicas e minerais já se mostrouviável, tanto do ponto de vista nutricional das plantas como no aspecto de reciclagem de áreas urbanas e urbanas como de resíduos industriais pela agricultura. Esta pesquisa teve como objetivo determinar a eficiência de um fertilizante organomineral formulado à base de lodo de esgoto em substituição ao adubo mineral no cultivo de cana-de-açúcar em ambientes com diferentes níveis de fertilidade do solo. Um experimento foi conduzido em ambiente de maior fertilidade do solo, no Instituto Federal Goiano -Campus, Morrinhos-GO, Brasil. O outro, em local com menor fertilidade do solo, na indústria de etanol no Vale do Tijuco, localizado no município de Rio do Peixe, no município de Prata-MG, Brasil. Utilizou-se o delineamento experimental de blocos ao acaso, em esquema fatorial 5 x 2 +1, correspondente a cinco níveis de adubação, com e sem bioestimulante mais um tratamento adicional com adubação mineral, em quatro repetições. As doses foram em função da recomendação de adubação de plantio e cobertura para cada ambiente, sendo composta por: 100% da fonte mineral e porcentagens de 0; 60; 80; 100 e 120% de fertilizante organomineral. Avaliou-se a produtividade, perfilhamento, diâmetro e altura de colmos.Em Prata -MG os diferentes percentuais da adubação de plantio favorece e incrementa produtividade, altura e diâmetro do colmo da cana-de-açúcar; o uso de bioestimulantes não contribui para o rendimento desta cultura. Em Morrinhos -GO os diferentes percentuais da adubação de plantio não melhora produtividade, perfilhamento, altura e diâmetro do colmo da cana-de-açúcar; o uso de bioestimulantes incrementa rendimento de produtividade da cana-de-açúcar. A adubação com fertilizante organomineral a base de biossólido é semelhante a adubação com fertilizante mineral nos ambientes

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The increasing production of biosolids in urban areas has been led to a search for alternative disposal avenues of this residue, which is rich in organic matter and nutrients. Agricultural land application of biosolids, motivated by its fertilizing power, is a widespread practice in many countries, but there are safety and regulatory concerns regarding the presence of pathogens in Class B biosolids. In addition, the scarcity of studies under tropical climate conditions raises questions that impede the agricultural use of this residue in some regions. The objective of this study was to evaluate the survival of thermotolerant coliforms over 12 months (52 weeks) after biosolids application on the surface of a Quartzipsamment neosol cultivated with Eucalyptus. Two different biosolids were studied: those generated by a biological treatment system with complete mixing aeration ponds followed by decantation ponds (Treatment A) and biosolids from a biological treatment system with conventional activated biosolids reactors (Treatment B), both delineated in randomized blocks with four replicates. After application on the forest soil, we estimated an average survival time of 54 weeks for thermotolerant coliforms present in Treatment A biosolids and 93 weeks in Treatment B biosolids. Thermotolerant coliforms persist much longer under tropical climate conditions in Brazil than in comparable studies under temperate climate conditions. This reaffirms the need to carry out studies covering the full range of moisture and temperature regimes in which biosolids are applied as fertilizer.

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