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1.
J Environ Manage ; 351: 119875, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157581

RESUMO

Phosphorus (P) removal from urban wastewater is increasingly relevant in the wastewater treatment sector. The present work aims to contribute to the study of the adsorption process as a P removal technology. Biogenic calcium carbonate from industrial eggshell waste prepared by milling and calcination was used as an adsorbent. Batch adsorption experiments were conducted using real wastewater with 40 mg P/L (orthophosphate), original pH 7.33, under stirring conditions (100 rpm). The adsorbent was characterized using SEM-EDS, XRD, and FTIR-ATR before and after adsorption. From an initial screening of calcination times (15, 30, 60, and 120 min) and considering a balance between P removal and energy saving, the adsorbent selected was eggshell calcined at 700 °C for 60 min. The Langmuir isotherms describe the experimental data with a maximum adsorption capacity of 4.57 mg P/g at 25 °C. The adsorption process reached equilibrium within 120 min for different dosages (5, 10, and 20 g/L at 25 °C). Batch experiments showed that SO42-, at a concentration of 2689 mg/L reduced the P adsorption selectivity for dosages ≤10 g/L at 25 °C. Characterization of the loaded adsorbent shows that P adsorption from real wastewater is mostly electrostatic attraction, with the contribution of ligand exchange and microprecipitation. The adsorption capacity and behavior of the selected adsorbent seem promising for P removal from urban wastewater compared with other low-cost adsorbents.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Fósforo/química , Adsorção , Carbonato de Cálcio/química , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Resíduos Industriais
2.
Environ Res ; 217: 114798, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36427636

RESUMO

The Guadiana Basin is a transnational basin, presenting historical contamination with potentially toxic metals (PTM), which origin can be both natural and anthropogenic. This study explores the use of a set of observational, chemical and ecotoxicological assays with Heterocypris incongruens, Vibrio fischeri, Pseudokirchneriella subcapitata, Thamnocephalus platyurus, identifying the most sensitive to be included in a toolbox to analyze the quality of freshwater sediments related to this type of contamination. The study included the analysis of a reservoir and streams sediments of Guadiana basin, in two consecutive years with different climate conditions 2017 (dry year) and 2018 (normal year). The results showed high chemical variability along the basin, with greater contamination with PTM in the reservoir sediments. The calculated Enrichment Factors (EF) indicated high anthropogenic contamination by Cd, followed by Pb (EF > 1.5). The geoaccumulation index (Igeo) revealed that the sediments were severely polluted with Cd, and slightly polluted with Pb and Cu, inducing a higher sublethal toxicity to Heterocypris incongruens. Among the parameters evaluated, and after the use of multivariate statistical techniques, the toolbox for assessing sediments quality, in similar climate and geological conditions, should include the analysis of: meteorology, land use/cover in the area, granulometry, organic matter content, PTM concentrations, contamination indices (e.g., Igeo and EF), and sublethal bioassays with H. incongruens (total sediment analysis) and Vibrio fisheri luminescence inhibition (pore water analysis).


Assuntos
Metais Pesados , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Cádmio/análise , Chumbo/análise , Monitoramento Ambiental/métodos , Água Doce , Sedimentos Geológicos/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Medição de Risco
3.
Trop Anim Health Prod ; 54(3): 180, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35522378

RESUMO

The purpose of this study was to evaluate the effect of retained placenta (RP) and clinical mastitis (CM) on the reproductive efficiency of crossbred dairy cows during the postpartum period and the effect in some innate immune system indicators. For this, two experiments were carried out. In the first, a total of 232 cows were evaluated and divided as: healthy control (n = 184), RP (n = 22), and CM (n = 26) groups. The RP and CM was evaluated until 30 days postpartum (DPP) and reproductive rates were measured. In experiment 2, cows were divided in control (n = 10), RP (n = 10), and CM (n = 30) groups. Between 40 and 50 DPP, clinical, gynecological examination and endometrial cytobrush were performed to evaluate subclinical endometritis (SE) and gene expression of interleukins 1ß (IL-1ß) and 6 (IL-6), chemokine ligand 5 (CCL5), estrogen α (ESR1), and progesterone (PGR) receptors by qRT-PCR analysis. In experiment 1, the conception rate at 1st artificial insemination (AI) was lower in RP and CM groups and pregnancy rate at 150 days decreased in CM group. Calving-to-1st AI interval and days open were shorter in healthy cows. In experiment 2, the occurrence of SE was 26.7% and higher in RP and CM groups. The expression of IL-1ß increased in RP and CM groups, while IL-6 was less expressed in RP group. The CCL5, ESR1, and PGR were similar between groups. In conclusion, cows with RP and CM had their reproductive efficiency negatively affected and had they initial pro-inflammatory response improved by the increase of IL-ß.


Assuntos
Doenças dos Bovinos , Endometrite , Mastite , Placenta Retida , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Endometrite/veterinária , Feminino , Expressão Gênica , Imunidade , Interleucina-6/farmacologia , Lactação , Mastite/veterinária , Placenta Retida/genética , Placenta Retida/veterinária , Período Pós-Parto , Gravidez , Reprodução
4.
Environ Monit Assess ; 192(2): 93, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907689

RESUMO

Water is a scarce resource in the Mediterranean region where adverse climatic conditions promoting water shortages tend to increase with climate change. Under water scarcity conditions and high atmosphere evaporative demand, the risks of decreased water quality, and land salinization are major threats to the sustainability of irrigated agriculture in this region. The assessment of the quality of irrigation water is increasingly important to ensure the maintenance of long-term salt balance at a crop, farm, and regional scale. This study is focused on the spatial and temporal variability of water quality for irrigation in the Alqueva reservoir (Southern Portugal). The assessment was performed every 2 months during a distinctive drought year (2017) and included inorganic ions (Na+, Ca2+, Mg2+, K+, NH4+, Cl-, F-, SO42-, NO3-, and NO2-), pH, and electric conductivity (ECW) of water. Sodium adsorption ratio (SAR) was calculated, and potential soil permeability problems were estimated. The assessment showed significantly higher values of the physicochemical parameters in the most upstream sites, located near tributaries inflows, and an upward trend in ion concentrations throughout the year, with significantly higher concentrations of Na+, Mg2+, Cl-, and SO42, registered through May to November, reflecting the severe drought felt in the summer, autumn, and winter. The evaluation of water quality for irrigation indicated a slight to moderate risk of reduced infiltration rates, which should be considered whenever sprinkler irrigation is used, mainly in fine-textured soils, which are prevalent in the irrigated area. The multivariate statistical approach, using principal component analysis and factor analysis, identified two principal components related to salinity and nutrient concentrations. The cluster analysis revealed three groups of similarity between samples pointing to a more time- than space-controlled pattern. Overall, the temporal dynamics of the water physicochemical parameters could indicate that an abnormal annual distribution of precipitation and temperature may distort seasonal differences. To prevent water and soil degradation, a more frequent assessment of the water quality should be considered, allowing for the selection of appropriate soil and water management measures in irrigated areas.


Assuntos
Irrigação Agrícola , Secas , Monitoramento Ambiental/métodos , Qualidade da Água , Água/química , Agricultura , Mudança Climática , Região do Mediterrâneo , Portugal , Salinidade , Estações do Ano , Sódio/análise , Solo/química , Abastecimento de Água
5.
Trop Anim Health Prod ; 53(1): 40, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33231751

RESUMO

The Azores archipelago is the most suitable region for dairy production in Portugal, representing 30% of the overall Portuguese dairy production. It has a production system characterized by an average milk yield of 6216 kg/cow/year, and the predominance of pasture-based feeding and cows that have longer productive lives and lower incidence of metabolic/production diseases, such as acidosis or mastitis. The biggest problem with the Azores Islands dairy sector is the cost of transport, as the main markets are located in continental Portugal, over 1500 km away, and local dairy products have to compete with dairy products produced in mainland Portugal and in the rest of the European Union. Herein, the evolution of the dairy sector in the Azores Islands from 2007 to 2017 is presented. A SWOT (Strength, Weakness, Opportunity, and Threat) analysis was performed to find potential solutions to increase the value of the Azorean dairy sector. The most relevant solution considered was the valorization of the dairy production through three major aspects: higher milk quality, namely, better organoleptic properties; lower carbon footprint (not considering transport costs); and higher levels of animal welfare. Three examples are shown of such valorization: protected denomination of origin (PDO) cheeses, the "happy cows" program, and the production of an organic milk, from the Terceira Island. Some of these programs are relatively recent, so, it will be interesting to see how their sales and acceptance by consumers evolve, particularly under the current economic framework.


Assuntos
Bem-Estar do Animal/economia , Pegada de Carbono/economia , Indústria de Laticínios/economia , Leite/economia , Animais , Açores , Leite/química
6.
Reprod Biomed Online ; 38(3): 300-311, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639159

RESUMO

RESEARCH QUESTION: Does a three-dimensional culture system based on magnetic levitation with nanoparticles assembly maintain the follicular structure and viability with adequate growth rates leading to oocyte maturation after long-term culture? DESIGN: Randomized-controlled trial of treatments in a bovine model. Secondary follicles (n = 213) isolated from bovine ovaries were cultured in a two-dimensional system (two-dimensional control) or three-dimensional levitation system with different concentrations (three-dimensional 50 µl/ml, 100 µl/ml and 200 µl/ml) of magnetic nanoparticles. Follicular growth (diameter, daily growth and growth patterns), morphology (normal, degenerated and extruded follicles), antrum formation, oocyte viability and chromatin configuration were assessed. RESULTS: Secondary follicles of three-dimensional 200-µl/ml treatment showed higher viability, antrum formation and lower degeneration rates than two-dimensional control. Also, follicles cultured in the three-dimensional 200-µl/ml treatment presented a most homogenous daily growth rate as shown by the lowest variance and standard deviation. Compared with the two-dimensional control, the proportion of non-growing and slow-growing follicles were 3.8-fold lower and 1.6-fold higher, respectively, in the three-dimensional 200-µl/ml treatment. After in-vitro maturation, the three-dimensional 200-µl/ml had a greater proportion of viable oocytes (1.7-fold) and meiotic resumption rates (2.4-fold) than the two-dimensional control treatment. CONCLUSION: The three-dimensional levitation culture system improves the viability of in-vitro development of bovine secondary follicles, antrum formation and lower extrusion and degeneration rates and adequate growth rate leading to relevant oocyte viability and meiotic resumption after in-vitro maturation. This approach does not require a specific medium, and has the potential as an alternative method to in-vitro follicle culture in several species, including humans.


Assuntos
Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/crescimento & desenvolvimento , Animais , Bovinos , Feminino , Técnicas de Maturação in Vitro de Oócitos/métodos , Recuperação de Oócitos/métodos , Recuperação de Oócitos/veterinária
7.
J Dairy Sci ; 102(6): 5511-5517, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30981492

RESUMO

Uterine inflammation negatively affects reproductive performance and is an important cause of infertility and subfertility in dairy cows. Several studies have investigated the use of gene expression in endometrial samples collected by biopsy or cytology to evaluate the inflammatory response of the cow uterus. This study aimed to compare the expression of the CCL5, CXCL8, IL6, and IL1B genes in the bovine endometrium according to the site of sample collection [caruncular (C) or intercaruncular (IC)], the collection method (biopsy or cytology), and the category of inflammation based on endometrial cytology (zero, medium, or high) in subclinical endometritis. The reproductive tracts of dairy cows were collected from a slaughterhouse, and punch-biopsy samples of endometrial tissues were obtained from both regions (C and IC). Endometrial cells from these regions were collected with the cytobrush technique and then used for the analysis of mRNA expression by quantitative PCR. After counting polymorphonuclear cells (PMN) by endometrial cytology, 20 uteri with an ovary at stage I (d 1-4 of estrous cycle) were categorized into 3 groups. Uteri with 0% PMN (n = 10) were assigned to group zero, uteri with 5 to 15% PMN (n = 5) to group medium (12.2 ± 1.6% PMN), and uteri with >15% PMN (n = 5) to group high (53.8 ± 32.9% PMN). All data were analyzed with 2-way ANOVA with Bonferroni multiple comparison post test. The results from gene transcripts demonstrated that the region (C or IC) of the endometrial biopsy had no influence on any of the degrees of inflammatory reaction observed. However, gene expression was more elevated in the endometrium of cows with greater inflammation compared with those without inflammation (CCL5, CXCL8, IL6, IL1B) and those with medium inflammation (CCL5, IL6). Expression of the genes evaluated did not differ between the endometrium without inflammation and with medium inflammation. However, in the high inflammation group, all genes were comparatively more expressed in samples collected by cytology relative to those derived from biopsies for both anatomical regions. In conclusion, gene expression did not differ between the C and IC tissue. Samples collected from animals with greater inflammation had greater gene expression than those with zero or medium inflammation. In addition, cytology samples had greater gene expression than biopsy samples in the high inflammation group.


Assuntos
Doenças dos Bovinos/patologia , Citocinas/genética , Endometrite/veterinária , Inflamação/veterinária , Reprodução , Animais , Biópsia/veterinária , Bovinos , Endometrite/patologia , Endométrio/patologia , Ciclo Estral , Feminino , Expressão Gênica , Inflamação/patologia , Neutrófilos/citologia , Ovário/patologia , RNA Mensageiro/genética , Útero/patologia
8.
Ecotoxicol Environ Saf ; 126: 102-110, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26741879

RESUMO

This study aimed to assess the potential impact on soil porewater, surface and groundwater from the beneficial application of organic wastes to soil, using their eluates and acute bioassays with aquatic organisms and plants: luminescence inhibition of Vibrio fischeri (15 and 30 min), Daphnia magna immobilization (48 h), Thamnocephalus platyurus survival (24 h), and seed germination of Lolium perenne (7 d) and Lactuca sativa (5 d). Some organic wastes' eluates promoted high toxic responses, but that toxicity could not be predicted by their chemical characterization, which is compulsory by regulatory documents. In fact, when organisms were exposed to the water-extractable chemical compounds of the organic wastes, the toxic responses were more connected to the degree of stabilization of the organic wastes, or to the treatment used to achieve that stabilization, than to their contaminant load. That is why the environmental risk assessment of the use of organic wastes as soil amendments should integrate bioassays with eluates, in order to correctly evaluate the effects of the most bioavailable fraction of all the chemical compounds, which can be difficult to predict from the characterization required in regulatory documents. According to our results, some rapid and standardized acute bioassays can be suggested to integrate a Tier 1 ecotoxicological evaluation of organic wastes with potential to be land applied, namely luminescence inhibition of V. fischeri, D. magna immobilization, and the germination of L. perenne and L. sativa.


Assuntos
Ecotoxicologia/métodos , Compostos Orgânicos/toxicidade , Resíduos/efeitos adversos , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise , Aliivibrio fischeri/efeitos dos fármacos , Animais , Bioensaio/métodos , Daphnia/efeitos dos fármacos , Germinação/efeitos dos fármacos , Lactuca/efeitos dos fármacos , Lolium/efeitos dos fármacos , Portugal , Solo , Poluentes do Solo/toxicidade , Águas Residuárias/toxicidade , Poluição Química da Água/efeitos adversos
9.
Sci Total Environ ; 861: 160670, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36473664

RESUMO

Producing microalgae with agricultural drainage water (ADW) allows recycling water and nutrients, with the production of a biofertilizer, avoiding receiving waters' contamination. Chlorella vulgaris and Scenedesmus obliquus were cultivated using ADW and standard media supplementation and presented higher productivities, relatively to the control industrial growth medium (using freshwater). Selected strains were grown outdoors in pilot flat panel photobioreactors, reaching 2.20 g L-1 for S. obliquus and 1.15 g L-1 for C. vulgaris, and degrading herbicides in the ADW to non-quantifiable concentrations. The potential of the C. vulgaris and S. obliquus suspensions to replace 50% of nitrogen (N) mineral fertilization of lettuce (0.5 g pot-1) was evaluated through a pot trial, also using a 2-times (1.0 g pot-1) and 5-times (2.5 g pot-1) higher dose, applied 31 days before lettuce transplanting. Even the lower dose of N, applied via C. vulgaris or S. obliquus suspensions, was able to provide significantly higher lettuce fresh matter yield, relatively to the mineral fertilized control. Soil enzymatic activities were improved, with significantly higher dehydrogenase, ß-glucosidase, and acid phosphatase activities for the 2.5 g pot-1 dose, more marked for S. obliquus, which was also able to increase soil organic matter content. Both the non-fertilized control and microalgae fertilized pots led to similar soil electrical conductivities, 3-fold lower than in the N-mineral fertilized pots, evidencing the capacity of microalgae fertilizers to avoid soil secondary salinization. Results suggest benefits from using ADW from maize cultivation to produce C. vulgaris or S. obliquus suspensions, that can be further used as liquid organic slow-release fertilizer.


Assuntos
Chlorella vulgaris , Fertilizantes , Scenedesmus , Microalgas , Solo , Água , Zea mays
10.
Sci Total Environ ; 887: 164012, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37169192

RESUMO

Arsenic, Cd, and Pb environmental fate is influenced when the traditional permanent flooding rice production systems are replaced by water-saving and soil conservation practices, urging for additional strategies that avoid their bioaccumulation in rice grain. The aim of this two-years field study was to evaluate the effects of fresh and field-aged biochar on As, Cd, and Pb bioaccumulation, and on As speciation, in rice grain produced in different growing environments (flooding versus sprinkler and conventional tillage versus direct seeding). Biochar produced from holm-oak pruning residues (pyrolysis at 550 °C, 48 h), in a single application (28 Mg ha-1), reduced As bioaccumulation in rice grain in the permanent flooding system to non-quantifiable concentrations (e.g., from 0.178 mg kg-1 to <0.04 mg kg-1, for inorganic-As, respectively), an effect which remained under field-aging conditions, increasing rice commercial value. When adopting sprinkler irrigation, the undesirable increase in Cd bioaccumulation in rice, relatively to the anaerobic system, was counteracted by biochar application, reducing its bioaccumulation in kernels between 32 and 80 %, allowing a simultaneous control of metals and metalloids bioaccumulation in rice. The bioaccumulation of Pb was also prevented with biochar application, with a reduction in its concentration four- to 13-times, in all the management systems, relatively to the non-amended plots, under fresh biochar effects. However, Pb immobilization decreased with biochar field-aging, indicating that the biochar application may have to be repeated to maintain the same beneficial effect. Therefore, the present study shows that the implementation of sprinkler irrigation with holm-oak biochar could reduce the risk of heavy metals(loids) bioaccumulation in rice grains and, thereby, ensuring food safety aspects, particularly under fresh biochar effects.


Assuntos
Oryza , Quercus , Poluentes do Solo , Cádmio/análise , Bioacumulação , Oryza/química , Chumbo , Solo/química , Carvão Vegetal/química , Poluentes do Solo/análise
11.
Sci Total Environ ; 835: 155488, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35476948

RESUMO

Sprinkler irrigation has been successfully introduced in rice production as an alternative to the traditional flooding system, allowing water savings and the reduction of As accumulation in the grain. However, the same conditions can increase Cd mobility and grain accumulation, an effect that needs to be countered. A 3-year field experiment was set-up in a Mediterranean region (Extremadura, Spain), to evaluate how the application of compost from olive mill waste (single application, 80 t ha-1), influences the accumulation of As and Cd in the grain under different irrigation regimes. Accumulation of As in the grain was always lower in the sprinkler irrigation when compared with the flooding irrigation, reaching a 5-fold difference in the third year. Compost application did not evidence a clear effect on the As accumulation in the rice grain, but highly significant negative correlations (p < 0.001) were obtained between As content in the grain (total, inorganic, and organic) and the humification parameters in the soil, evidencing the importance of using a mature and stable organic amendment to avoid As accumulation in the grain. Cadmium accumulation in the rice grain decreased in each treatment where compost was applied, relatively to the non-treated counterpart (e.g., from 0.080 to <0.010 mg kg-1, in direct seeding with sprinkler irrigation, in the third year). There were no significant differences in the total inorganic As between treatments with or without compost application, but it was possible to observe an increase in the predominance of the organic As over the more toxic inorganic As, when compost was applied, allowing a decrease in the risk associated to As accumulation. Therefore, the aerobic cultivation of rice, with the simultaneous application of an adequate source of organic matter, can be considered a good solution to cope with the risk of accumulation of As and Cd in the rice grain.


Assuntos
Arsênio , Compostagem , Olea , Oryza , Poluentes do Solo , Arsênio/análise , Cádmio/análise , Grão Comestível/química , Solo , Poluentes do Solo/análise
12.
PLoS One ; 17(10): e0275396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36194590

RESUMO

Understanding the transition from quiescent primordial follicles to activated primary follicles is vital for characterizing ovarian folliculogenesis and improving assisted reproductive techniques. To date, no study has investigated preantral follicle crowding in the ovaries of livestock or characterized these crowds according to follicular morphology and ovarian location (portions and regions) in any species. Therefore, the present study aimed to assess the crowding (clustering and neighborhood) patterns of preantral follicles in the equine ovary according to mare age, follicular morphology and developmental stage, and spatial location in the ovary. Ovaries from mares (n = 8) were collected at an abattoir and processed histologically for evaluation of follicular clustering using the Morisita Index and follicular neighborhoods in ovarian sections. Young mares were found to have a large number of preantral follicles with neighbors (n = 2,626), while old mares had a small number (n = 305). Moreover, young mares had a higher number of neighbors per follicle (2.6 ± 0.0) than old mares (1.2 ± 0.1). Follicle clustering was shown to be present in all areas of the ovary, with young mares having more clustering overall than old mares and a tendency for higher clustering in the ventral region when ages were combined. Furthermore, follicles with neighbors were more likely to be morphologically normal (76.5 ± 6.5%) than abnormal (23.5 ± 6.5%). Additionally, morphologically normal activated follicles had increased odds of having neighbors than normal resting follicles, and these normal activated follicles had more neighbors (2.6 ± 0.1) than normal resting follicles (2.3 ± 0.1 neighbors). In the present study, it was demonstrated that preantral follicles do crowd in the mare ovary and that clustering/neighborhood patterns are dynamic and differ depending on mare age, follicular morphology, and follicular developmental stage.


Assuntos
Folículo Ovariano , Ovário , Animais , Análise por Conglomerados , Feminino , Cavalos
13.
Chemosphere ; 284: 131258, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34225107

RESUMO

Phosphorus (P) is a non-renewable resource, irreplaceable for life and food production, and currently considered a Critical Raw Material to the European Union (EU). Due to concerns about the rate of consumption and limited reserves in countries with sensitive geopolitical contexts, it is urgent to recover P from urban and industrial flows. Indeed, the municipal wastewater treatment plants (WWTP) are considered relevant sources with several hot spots, especially sewage sludge with estimated recovery efficiencies of >80%. The most promising recovery strategies are based on thermal treatments (e.g., incineration of sludge) following by wet-chemical or thermo-chemical leaching, precipitation, and adsorption. The direct application of sludge on soil is no longer a primary route for P reintegration in the value-chain for countries as Switzerland, Germany, and The Netherlands. In fact, Switzerland and Austria paved the way for implementing P recovery legislation, focusing on recovery from raw sewage sludge or ashes. Indeed, industrial technologies with sludge ash as input show high recovery efficiencies (Ashdec® and Leachphos® with 98 and 79%) and lower environmental impacts, whereas Pearl® technology has about 12% recovery efficiency with wastewater as input. After all, struvite emerges as the most recovered product with recent access to the internal market of EU fertilisers and similar growth performance compared to triple-super-phosphate. However, several studies leave open the possibility of introducing loaded adsorbents with P as soil amendments as a new alternative to conventional desorption. Briefly, P recovery should be a compromise between efficiency, environmental impacts, and economic revenues from the final products.


Assuntos
Fertilizantes , Águas Residuárias , Incineração , Fósforo , Esgotos
14.
Environ Monit Assess ; 165(1-4): 539-52, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19444629

RESUMO

Multivariate statistical techniques were applied to evaluate spatial/temporal variations, and to interpret water quality data set obtained at Alqueva reservoir (south of Portugal). The water quality was monitored at nine different sites, along the water line, over a period of 18 months (from January 2006 to May 2007) using 26 water quality parameters. The cluster analysis allowed the formation of five different similarity groups between sampling sites, reflecting differences on the water quality at different locations of the Alqueva reservoir system. The PCA/FA identified six varifactors, which were responsible for 64% of total variance in water quality data set. The principal parameters, which explained the variability of quality water, were total phosphorus, oxidability, iron, parameters that at high concentrations indicate pollution from anthropogenic sources, and herbicides indicative of an intensive agricultural activity. The spatial analysis showed that the water quality was worse in the north of the reservoir.


Assuntos
Poluentes Químicos da Água/análise , Análise por Conglomerados , Monitoramento Ambiental/estatística & dados numéricos , Água Doce/química , Modelos Estatísticos , Análise Multivariada , Portugal , Análise de Componente Principal
15.
Sci Total Environ ; 686: 1152-1163, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31412511

RESUMO

Fly ash (FA) from biomass combustion and biological sludge (S), both wastes from the pulp and paper industry, were granulated in different proportions (90% FA+10% S, and 70% FA+30% S w/w, dry weight basis, dw) and used to recover the functionality of soils affected by mining activities (Aljustrel, Iberian Pyrite Belt), with and without the application of municipal solid waste compost (MSWC). Application doses of both mixtures were 2.5, 5.0 and 10% (w/w, dw). These materials corrected soil acidity to circumneutral values and increased extractable P and K concentrations. A significant increase in soil organic matter (from 0.6 to 0.8-1.5% w/w, dw) and N content (from 0.04 to 0.09-0.12% w/w, dw) was also observed, but only when MSWC was applied. The soil was already heavily contaminated with Cu, Pb and Zn and the application of amendments did not increase their pseudo-total concentrations. The CaCl2 extractable fractions of both Cu and Zn decreased to very low values. The improvement in soil quality, compared to fertilizer only treatment, was further evidenced by the increase in some soil enzymatic activities (dehydrogenase, ß-glucosidase and cellulase), with a better response for the granules with the higher proportion of biological sludge, as well as by the decrease in the soil-water extract toxicity towards different organisms (Daphnia magna, Thamnocephalus platyurus, and Pseudokirchneriella subcapitata). Agrostis tenuis germinated and grew during the first month only in the amended pots, but, after that, a considerable phytotoxic effect was evident. This was mainly attributed to salt stress or to some specific ionic toxicity. In conclusion, to establish a long-term plant cover in mining soils amended with biomass ash-based materials, the selection of plants with higher resistance to salinity and/or the stabilization of the amendments, to reduce their soluble salt content, is recommended.


Assuntos
Agrostis/metabolismo , Poluição Ambiental/prevenção & controle , Recuperação e Remediação Ambiental/métodos , Resíduos Industriais/análise , Poluentes do Solo/metabolismo , Solo/química , Agrostis/crescimento & desenvolvimento , Biodegradação Ambiental , Biomassa , Cinza de Carvão/análise , Mineração , Papel
16.
Sci Total Environ ; 659: 84-94, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597472

RESUMO

The mine abandonment is generally associated with the release of potentially toxic metals into the environment, which may depend on metals speciation, soil properties and climate conditions. The goal of the present work was to assess the environmental impact of the abandoned Pb-Zn mine "Las Musas" (Spain) using an integrative approach. The impact on soils and surface waters was performed using: chemical parameters, quantification of potentially toxic metals (Cd, Cu, Pb and Zn), and ecotoxicological responses using lethal and sub-lethal bioassays with organisms' representative of different trophic level ((soil: Eisenia fetida (mortality and reproduction test); Latuca sativa and Lollium perenne (seedling emergence); and water: Vibrio fischeri (luminescence inhibition), Daphnia magna (immobility and reproduction test), Thamnocephalus platyurus (mortality), Pseudokirchneriella subcapitata (growth inhibition)). The results showed soils with neutral to slight alkaline pH (7.64-8.18), low electric conductivity (125-953 µS/cm) and low organic matter levels (0.20-1.85%). For most of the soil samples, Pb was the only metal which surpassed the limit proposed by the Canadian soil quality guidelines, with values ranging from 42.2 to 181.4 mg/kg. The ecotoxicological results showed that the soils with the highest levels of Pb induced a decrease on E. fetida reproduction and on L. sativa germination, indicating negative impacts on the habitat function. The analysis of the surface waters showed levels of Zn surpassing the legal limit adopted from the Water Framework Directive (37.0 to 69.0 µg/L). The ecotoxicological results highlight the importance of bioassays that evaluate the behavior of species, when assessing the risk of mining areas with non-acid soils and waters with high nutrients/organic matter concentrations and low concentrations of potentially toxic metals. The results indicated a moderate environmental risk from potentially toxic metals, at the areas analyzed around the Azuaga mine.


Assuntos
Monitoramento Ambiental , Metais Pesados/toxicidade , Mineração , Poluentes do Solo/toxicidade , Poluentes Químicos da Água/toxicidade , Medição de Risco , Espanha , Testes de Toxicidade
17.
Environ Toxicol Chem ; 38(7): 1569-1576, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30985941

RESUMO

The use of organic wastes as soil amendments can be an important measure to improve soil quality and reduce waste accumulation and landfilling. However, the potential contaminant loads of such wastes, can be a source of environmental concern. Consequently, legislation has been developed to regulate the use of these wastes in agricultural soils. However, the regulations only consider chemical parameters, which are insufficient to establish the level of environmental risk. A possible solution is the use of species sensitivity distributions (SSDs), employing ecotoxicological data from test batteries that could be incorporated into legislation. In the present study, 2 different hazardous concentrations affecting 5 and 50% of the soil community (HC5 and HC50, respectively) were determined using ecotoxicological data (effect concentrations, 10 and 50% [EC10 and EC50, respectively]) for 5 different wastes. The results demonstrate that, as expected, current legislative thresholds do not translate to environmental risk/protection and that SSDs may be an important tool allowing the simple inclusion and interpretation of ecotoxicological data from test batteries in legislation. On the other hand, SSDs must be used with caution because there are still doubts about their actual value in risk prediction and about which estimates provide adequate protection. For instance, the use of HC50EC10 values is not recommended; these values overlap with the more conservative HC5EC50 data, highlighting the fact that the use of lower effect concentrations may not always provide the most protective approach. Also, hazardous concentrations need to be calibrated at the field or semifield level, to verify environmental protection in different soils/environments and the adequacy of standard test organisms. Environ Toxicol Chem 2019;38:1569-1576. © 2019 SETAC.


Assuntos
Esgotos/química , Poluentes do Solo/química , Animais , Anelídeos/efeitos dos fármacos , Anelídeos/fisiologia , Aracnídeos/efeitos dos fármacos , Aracnídeos/fisiologia , Lactuca/efeitos dos fármacos , Lactuca/crescimento & desenvolvimento , Lactuca/metabolismo , Lolium/efeitos dos fármacos , Lolium/crescimento & desenvolvimento , Lolium/metabolismo , Metais/química , Metais/toxicidade , Reprodução/efeitos dos fármacos , Poluentes do Solo/toxicidade , Especificidade da Espécie
18.
J Hazard Mater ; 330: 149-156, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28279835

RESUMO

Using organic wastes, as soil amendments, is an important alternative to landfilling with benefits to soil structure, water retention, soil nutrient and organic matter concentrations. However, this practice should be monitored for its environmental risk due to the frequent presence, of noxious substances to soil organisms. To evaluate the potential of eight organic wastes with different origins, as soil amendments, reproduction tests with four soil invertebrate species (Folsomia candida, Enchytraeus crypticus, Hypoaspis aculeifer, Eisenia fetida) were performed using gradients of soil-waste mixtures. Results obtained demonstrated that contaminant concentrations required by current legislation might not be a protective measure for the soil ecosystem, as they do not properly translate the potential toxicity of wastes to soil invertebrates. Some wastes with contaminant loadings below thresholds showed higher toxicity than wastes with contaminants concentrations above legal limits. Also, test organism reproduction was differently sensitive to the selected wastes, which highlights the need to account for different organism sensitivities and routes of exposure when evaluating the toxicity of such complex mixtures. Finally this study shows that when combining chemical and ecotoxicological data, it is possible to postulate on potential sources of toxicity, contributing to better waste management practices and safer soil organic amendment products.


Assuntos
Anelídeos/efeitos dos fármacos , Artrópodes/efeitos dos fármacos , Solo , Resíduos/efeitos adversos , Animais , Reprodução/efeitos dos fármacos , Resíduos/análise
19.
World Neurosurg ; 102: 466-476, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28216398

RESUMO

OBJECTIVE: Many new endovascular devices have been used under the guidance of the International Subarachnoid Aneurysm Trial. Clipping still offers higher occlusion rates, and its technique continues to evolve, resulting in smaller exposures and reduced manipulation to brain tissue. We sought to evaluate the routine use of the minisphenoidal approach to manage intracranial aneurysms in a high-volume institution. METHODS: We retrospectively reviewed our database of patients with aneurysm from October 2013 to May 2016. Data were originally collected prospectively. The minisphenoidal approach has been progressively replacing the pterional approach for managing aneurysms in our department. Occlusion rates for ruptured and unruptured aneurysms were analyzed using late follow-up angiograms. Functional outcome assessment and the impact on quality of life were also measured. RESULTS: We performed 124 minisphenoidal craniotomies in 117 patients to clip 147 aneurysms. Patient mean age was 53.9 years. Seventy patients (59.8%) presented with subarachnoid hemorrhage. Middle cerebral artery aneurysms represented 48% of the total number of aneurysms; posterior communicating artery aneurysms represented 24%. The minisphenoidal craniotomy was helpful in managing superior cerebellar artery aneurysms and 1 ruptured orbitofrontal artery aneurysm. We achieved an occlusion rate of 97.8%, with a mean follow-up of 13.2 months. Favorable outcomes were achieved for 79% of patients with subarachnoid hemorrhage and for 98% of unruptured patients. CONCLUSIONS: Evolution of endovascular techniques has paved the way for minimizing surgical exposures. Routine use of the minisphenoidal approach for managing ruptured, unruptured, and previously coiled aneurysms is safe and provides adequate exposure with robust occlusion rates.


Assuntos
Aneurisma Roto/cirurgia , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/cirurgia , Instrumentos Cirúrgicos , Adolescente , Adulto , Idoso , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/psicologia , Angiografia Digital , Angiografia por Tomografia Computadorizada , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/psicologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
20.
Waste Manag ; 40: 44-52, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25708406

RESUMO

Nine different samples of sewage sludges, composts and other representative organic wastes, with potential interest to be used as agricultural soil amendments, were characterized: municipal sewage sludge (SS1 and SS2), agro industrial sludge (AIS), municipal slaughterhouse sludge (MSS), mixed municipal solid waste compost (MMSWC), agricultural wastes compost (AWC), compost produced from agricultural wastes and sewage sludge (AWSSC), pig slurry digestate (PSD) and paper mill wastes (PMW). The characterization was made considering their: (i) physicochemical parameters, (ii) total and bioavailable heavy metals (Cd, Cr, Cu, Ni, Pb, Zn and Hg), (iii) organic contaminants, (iv) pathogenic microorganisms and (v) stability and phytotoxicity indicators. All the sludges, municipal or other, comply with the requirements of the legislation regarding the possibility of their application to agricultural soil (with the exception of SS2, due to its pathogenic microorganisms content), with a content of organic matter and nutrients that make them interesting to be applied to soil. The composts presented, in general, some constraints regarding their application to soil, and their impairment was due to the existence of heavy metal concentrations exceeding the proposed limit of the draft European legislation. As a consequence, with the exception of AWSSC, most compost samples were not able to meet these quality criteria, which are more conservative for compost than for sewage sludge. From the results, the composting of sewage sludge is recommended as a way to turn a less stabilized waste into a material that is no longer classified as a waste and, judging by the results of this work, with lower heavy metal content than the other composted materials, and without sanitation problems.


Assuntos
Metais Pesados/análise , Eliminação de Resíduos/métodos , Esgotos/química , Matadouros , Agricultura/métodos , Animais , Concentração de Íons de Hidrogênio , Metais , Nitrogênio/química , Compostos Orgânicos/química , Papel , Fósforo/química , Portugal , Potássio/química , Medição de Risco , Solo , Poluentes do Solo/química , Resíduos Sólidos , Suínos , Gerenciamento de Resíduos/métodos
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