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1.
Nanomaterials (Basel) ; 13(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37446445

RESUMO

Today, sustainability represents the key factor for economic progress in compliance with social advancement and environmental protection, driving innovation in materials, processes and technologies [...].

2.
Polymers (Basel) ; 16(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38201789

RESUMO

The current era has been defined as "The Plastic Era", considering that over the past 50 years the role and importance of polymeric materials in our economy has steadily grown, reaching a production of around a few hundred million tons per year which may even double in the next 20 years [...].

3.
Nanomaterials (Basel) ; 12(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35889551

RESUMO

Mono-doped (Mo-TiO2 and W-TiO2) and co-doped TiO2 (Co-Mo-TiO2, Co-W-TiO2, Cu-Mo-TiO2, Cu-W-TiO2, Zn-Mo-TiO2, and Zn-W-TiO2) catalysts were synthesized by simple impregnation methods and tested for the photocatalytic degradation of 4-tert-butylphenol in water under UV (365 nm) light irradiation. The catalysts were characterized with various analytical methods. X-ray diffraction (XRD), Raman, Diffuse reflectance (DR) spectroscopies, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and Energy dispersive spectroscopy (EDS) were applied to investigate the structure, optical properties, morphology, and elemental composition of the prepared catalysts. The XRD patterns revealed the presence of peaks corresponding to the WO3 in W-TiO2, Co-W-TiO2, Cu-W-TiO2, and Zn-W-TiO2. The co-doping of Cu and Mo to the TiO2 lattice was evidenced by the shift of XRD planes towards higher 2θ values, confirming the lattice distortion. Elemental mapping images confirmed the successful impregnation and uniform distribution of metal particles on the TiO2 surface. Compared to undoped TiO2, Mo-TiO2 and W-TiO2 exhibited a lower energy gap. Further incorporation of Mo-TiO2 with Co or Cu introduced slight changes in energy gap and light absorption characteristics, particularly visible light absorption. In addition, photoluminescence (PL) showed that Cu-Mo-TiO2 has a weaker PL intensity than undoped TiO2. Thus, Cu-Mo-TiO2 showed better catalytic activity than pure TiO2, achieving complete degradation of 4-tert-butylphenol under UV light irradiation after 60 min. The application of Cu-Mo-TiO2 under solar light conditions was also tested, and 70% of 4-tert-butylphenol degradation was achieved within 150 min.

4.
J Sep Sci ; 45(14): 2566-2581, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35568470

RESUMO

Analysis of vancomycin and teicoplanin in biological fluids is vital since they are used in the treatment of hospital infections. For the determination of both glycopeptides in urine, a sensitive and accurate analytical method using high-performance liquid chromatography coupled with photodiode array and mass spectrometry was developed and validated. This research work is the first attempt to develop a chromatographic method for the determination of two glycopeptides with structural similarities. Moreover, the used non-invasive sampling method is an advantage of this research effort, especially when the blood sampling is difficult. Urine was treated with acetonitrile and 5% trichloroacetic acid, followed by solid-phase extraction. The chromatographic separation was established at a C18 column (4.6 × 150 mm, 5 µm), using a gradient method and an electrospray ionization source in a positive mode. The linearity of the method was R2 ≥ 0.9900. The precision was estimated with a maximum coefficient of variation below 15%, while the accuracy ranged from 64 to 121%. The limit of detection and quantification of both glycopeptides ranged from 0.076 up to 0.33 mg/L and 0.33 up to 2.1 mg/L, respectively, showing the same sensitivity as the triple quadrupole mass spectrometry, which is the most frequently used method.


Assuntos
Teicoplanina , Vancomicina , Cromatografia Líquida de Alta Pressão/métodos , Glicopeptídeos , Humanos , Espectrometria de Massas/métodos
5.
Nanomaterials (Basel) ; 12(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35055213

RESUMO

Biochar from spent malt rootlets was employed as the template to synthesize hybrid biochar-ceria materials through a wet impregnation method. The materials were tested for the activation of persulfate (SPS) and subsequent degradation of sulfamethoxazole (SMX), a representative antibiotic, in various matrices. Different calcination temperatures in the range 300-500 °C were employed and the resulting materials were characterized by means of N2 adsorption and potentiometric mass titration as well as TGA, XRD, SEM, FTIR, DRS, and Raman spectroscopy. Calcination temperature affects the biochar content and the physicochemical properties of the hybrid materials, which were tested for the degradation of 500 µg L-1 SMX with SPS (in the range 200-500 mg L-1) in various matrices including ultrapure water (UPW), bottled water, wastewater, and UPW spiked with bicarbonate, chloride, or humic acid. Materials calcined at 300-350 °C, with a surface area of ca. 120 m2 g-1, were the most active, yielding ca. 65% SMX degradation after 120 min of reaction in UPW; materials calcined at higher temperatures as well as bare biochar were less active. Degradation decreased with increasing matrix complexity due to the interactions amongst the surface, the contaminant, and the oxidant. Experiments in the presence of scavengers (i.e., methanol, t-butanol, and sodium azide) revealed that sulfate and hydroxyl radicals as well as singlet oxygen were the main oxidative species.

6.
Addiction ; 115(1): 109-120, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31642141

RESUMO

BACKGROUND AND AIMS: Wastewater-based epidemiology is an additional indicator of drug use that is gaining reliability to complement the current established panel of indicators. The aims of this study were to: (i) assess spatial and temporal trends of population-normalized mass loads of benzoylecgonine, amphetamine, methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) in raw wastewater over 7 years (2011-17); (ii) address overall drug use by estimating the average number of combined doses consumed per day in each city; and (iii) compare these with existing prevalence and seizure data. DESIGN: Analysis of daily raw wastewater composite samples collected over 1 week per year from 2011 to 2017. SETTING AND PARTICIPANTS: Catchment areas of 143 wastewater treatment plants in 120 cities in 37 countries. MEASUREMENTS: Parent substances (amphetamine, methamphetamine and MDMA) and the metabolites of cocaine (benzoylecgonine) and of Δ9 -tetrahydrocannabinol (11-nor-9-carboxy-Δ9 -tetrahydrocannabinol) were measured in wastewater using liquid chromatography-tandem mass spectrometry. Daily mass loads (mg/day) were normalized to catchment population (mg/1000 people/day) and converted to the number of combined doses consumed per day. Spatial differences were assessed world-wide, and temporal trends were discerned at European level by comparing 2011-13 drug loads versus 2014-17 loads. FINDINGS: Benzoylecgonine was the stimulant metabolite detected at higher loads in southern and western Europe, and amphetamine, MDMA and methamphetamine in East and North-Central Europe. In other continents, methamphetamine showed the highest levels in the United States and Australia and benzoylecgonine in South America. During the reporting period, benzoylecgonine loads increased in general across Europe, amphetamine and methamphetamine levels fluctuated and MDMA underwent an intermittent upsurge. CONCLUSIONS: The analysis of wastewater to quantify drug loads provides near real-time drug use estimates that globally correspond to prevalence and seizure data.


Assuntos
Monitoramento Ambiental/métodos , Drogas Ilícitas , Análise Espaço-Temporal , Detecção do Abuso de Substâncias/métodos , Águas Residuárias/química , Anfetamina/análise , Cromatografia Líquida , Cocaína/análogos & derivados , Cocaína/análise , Humanos , Internacionalidade , Metanfetamina/análise , N-Metil-3,4-Metilenodioxianfetamina/análise , Espectrometria de Massas em Tandem
7.
Sci Total Environ ; 647: 1169-1178, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30180325

RESUMO

Pharmaceutically active compounds (PhACs) released in agroecosystems have been found to be taken up by and accumulated in the edible parts of crop plants. By employing simulated hydroponic cultivation under controlled conditions, the present study aimed at evaluating 1) the uptake and bioaccumulation of three common PhACs (diclofenac, DCF; sulfamethoxazole, SMX; trimethoprim, TMP), either applied individually (10 µg L-1) or as mixture (10 µg L-1 each), in tomato fruits harvested from the first three fruit sets, and 2) the PhACs-mediated effects on fruit quality attributes. DCF was not detected in tomato fruits, whereas both SMX and TMP were detected in varying concentrations in fruits, depending on the time of harvest, the mode of application and the allocation of plants in the greenhouse. The studied PhACs applied at environmentally relevant concentrations did not significantly affect plant productivity. Nevertheless, important fruit quality attributes, such as soluble solids and carbohydrate (fructose, glucose, sucrose, total sugars) content were significantly impacted by all studied PhACs applied individually, suggesting that for DCF, potentially its transformation products (TPs) (not examined in this study) may exert significant effects on fruits quality attributes. In addition, no additive or synergistic effects of the mixture of PhACs on studied fruits quality attributes were revealed. Gene expression analysis showed that the PhACs-mediated effects on the carbohydrate content of fruits can be attributed, at least to some extent, to the significant modulation of the abundance of transcripts related to the biosynthesis and catabolism of sucrose, such as SlSuSys, SlLin5 and SlLin7. To our knowledge, this is the first report highlighting the potential effects of PhACs released in agroecosystems on the quality of widely consumed agricultural products. In any case, further studies are warranted for the overall assessment of the potential impacts of PhACs on the quality of agricultural products under conventional agricultural conditions.


Assuntos
Preparações Farmacêuticas/análise , Poluentes do Solo/análise , Solanum lycopersicum/química , Agricultura , Frutas , Solanum lycopersicum/metabolismo , Preparações Farmacêuticas/metabolismo , Poluentes do Solo/metabolismo , Sacarose , Sulfametoxazol/análise , Sulfametoxazol/metabolismo
8.
Environ Sci Pollut Res Int ; 25(19): 18226-18241, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28390021

RESUMO

Pharmaceutically active substances (PhACs) and drugs of abuse (DAs) are two classes of contaminants of emerging concern that have attracted great concern and interest by the scientific community during the last two decades. Numerous studies have revealed their presence in treated urban wastewaters. This is mainly due to the fact that some compounds are not efficiently removed during wastewater treatment processes, and are thus able to reach the aquatic environment through wastewater discharge and reuse practices. The application of an optimized multi-residue method for the simultaneous confirmation and quantification of licit and illicit drugs has been investigated in influent and effluent wastewater samples from seven wastewater treatment plants (WWTPs) located in north-eastern Tunisia. Analysis was performed through ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Out of 12 pharmaceutical compounds analyzed, 11 of them were detected mainly in effluent wastewaters. In both matrices, antibiotics and ß-blockers were the most detected groups. This suggests that these compounds show noticeable resistance against biological treatment in WWTPs. The estimated concentrations of antibiotics in effluents ranged from ca. 35 ng/L to 1.2 µg/L. However, all five studied illicit drugs were detected, mainly in influent wastewaters. Forensic investigation performed on people suspected to be drug abusers covering all Tunisian cities was conducted by monitoring an epidemiological study of human urine samples surveying rate of consumption for illicit drugs. Hence, these preliminary results confirmed the presence of illicit drugs in the influent wastewater samples. For example, quantification ranges for cocaine were found to be 25-450 ng/L in influent wastewater samples. Significant differences for cocaine consumption across the two sampling methods were observed. Consequently, we conclude that the analyses in wastewater are more reflective of the real levels of illicit drug consumption. Moreover, the cost for chromatographic analysis is lower than the screening test methods for human biological specimen, particularly staffing, which are likely to be much lower.


Assuntos
Antagonistas Adrenérgicos beta/análise , Antibacterianos/análise , Monitoramento Ambiental/métodos , Drogas Ilícitas/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Cidades , Humanos , Tunísia , Purificação da Água/métodos
9.
Environ Sci Pollut Res Int ; 24(29): 23371-23381, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28842853

RESUMO

Veterinary antibiotics could enter the environment after the application of manure or farm wastewater on soil as fertilizer. In this study, a UPLC-MS/MS analytical method was developed and validated for the simultaneous determination of enrofloxacin (ENR) and ciprofloxacin (CIP) at environmental relevant concentrations in piggery wastewater, piggery wastewater solids, agricultural soil and ground water with good performance characteristics. The method recovery for ENR and CIP was 94.2 and 89.9% in the filtered piggery wastewater, 81.3 and 82% in the wastewater solid material, 78.1 and 76.8% in the soil and 95.6 and 97.3% in the ground water. The Limit of Detection (LOD) and Limit of Quantification (LOQ) for ENR were 21 and 64 ng L-1 and for CIP was 18 and 54 ng L-1, respectively. The method was implemented to monitor ENR and CIP in the wastewater of a piggery facility in Cyprus which applied anaerobic treatment before the final disposal of the reclaimed water. The highest antibiotic concentrations were measured in the wastewater samples collected from the nursery, where ENR is continuously used, with average concentration 31.4 µg L-1 for ENR and 16.0 µg L-1 for CIP. After the anaerobic digester, the two antibiotics were found only on the solid matter of the treated wastewater with an average concentration of 1.7 µg kg-1 for ENR and 1.0 µg kg-1 for CIP. The antibiotics adsorption at pH = 7 on clay soil, quartz sand and on solid matter isolated from the piggery wastewater was found to be higher than 95% for all solid materials. The concentration of the antibiotics in soil samples taken from a field where reclaimed piggery wastewater was applied for 10 years and in samples of groundwater from a nearby well was found for all samples below the LOD.


Assuntos
Ciprofloxacina/análise , Fluoroquinolonas/análise , Solo/química , Drogas Veterinárias/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Adsorção , Cromatografia Líquida de Alta Pressão , Chipre , Enrofloxacina , Fertilizantes/análise , Água Subterrânea/química , Esterco/análise , Espectrometria de Massas em Tandem , Águas Residuárias/análise
11.
Environ Int ; 99: 131-150, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28038971

RESUMO

The information obtained from the chemical analysis of specific human excretion products (biomarkers) in urban wastewater can be used to estimate the exposure or consumption of the population under investigation to a defined substance. A proper biomarker can provide relevant information about lifestyle habits, health and wellbeing, but its selection is not an easy task as it should fulfil several specific requirements in order to be successfully employed. This paper aims to summarize the current knowledge related to the most relevant biomarkers used so far. In addition, some potential wastewater biomarkers that could be used for future applications were evaluated. For this purpose, representative chemical classes have been chosen and grouped in four main categories: (i) those that provide estimates of lifestyle factors and substance use, (ii) those used to estimate the exposure to toxicants present in the environment and food, (iii) those that have the potential to provide information about public health and illness and (iv) those used to estimate the population size. To facilitate the evaluation of the eligibility of a compound as a biomarker, information, when available, on stability in urine and wastewater and pharmacokinetic data (i.e. metabolism and urinary excretion profile) has been reviewed. Finally, several needs and recommendations for future research are proposed.


Assuntos
Biomarcadores/análise , Poluentes Ambientais/análise , Preparações Farmacêuticas/análise , Densidade Demográfica , Saúde Pública , Águas Residuárias/análise , Humanos , Estilo de Vida
12.
Water Res ; 109: 24-34, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27865170

RESUMO

Wastewater (WW) reuse for vegetable crops irrigation is regularly applied worldwide. Such a practice has been found to allow the uptake of pharmaceutical active compounds (PhACs) by plants and their subsequent entrance to the food web, representing an important alternative pathway for the exposure of humans to PhACs, with potential health implications. Herein we report the impacts of the long-term (three consecutive years) WW irrigation of a tomato crop with two differently treated effluents under real agricultural conditions, on (1) the soil concentration of selected PhACs (i.e. diclofenac, DCF; sulfamethoxazole, SMX; trimethoprim, TMP), (2) the bioaccumulation of these PhACs in tomato fruits, and (3) the human risks associated with the consumption of WW-irrigated fruits. Results revealed that the concentration of the studied PhACs in both the soil and tomato fruits varied depending on the qualitative characteristics of the treated effluent applied and the duration of WW irrigation. The PhAC with the highest soil concentration throughout the studied period was SMX (0.98 µg kg-1), followed by TMP (0.62 µg kg-1) and DCF (0.35 µg kg-1). DCF was not found in tomato fruits harvested from WW-irrigated plants during the first year of the study. However, DCF displayed the highest fruit concentration (11.63 µg kg-1) throughout the study (as a result of prolonged WW irrigation), followed by SMX (5.26 µg kg-1) and TMP (3.40 µg kg-1). The calculated fruit bioconcentration factors (BCFF) were extremely high for DCF in the 2nd (108) and 3rd year (132) of the experimental period, with the respective values for SMX (0.5-5.4) and TMP (0.2-6.4) being significantly lower. The estimated threshold of toxicity concern (TTC) and hazard quotients (HQ) values revealed that the consumption of fruits harvested from tomato plants irrigated for long period with the WW applied for irrigation under field conditions in this study represent a de minimis risk to human health. However, more studies need to be performed in order to obtain more solid information on the safety of WW reuse for irrigation.


Assuntos
Verduras , Águas Residuárias , Irrigação Agrícola , Frutas , Humanos , Solanum lycopersicum , Medição de Risco , Solo
13.
Environ Toxicol Chem ; 35(11): 2753-2764, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27043355

RESUMO

The selection and prioritization of pharmaceuticals and their transformation products for evaluating effects on the environment and human health is a challenging task. One common approach is based on compounds (e.g., mixture composition, concentrations), and another on biology (e.g., relevant endpoint, biological organizational level). Both of these approaches often resemble a Lernaean Hydra-they can create more questions than answers. The present study embraces this complexity, providing an integrated approach toward assessing the potential effects of transformation products of pharmaceuticals by means of mutagenicity, estrogenicity, and differences in the gene expression profiles. Mutagenicity using the tk kinase assay was applied to assess a list of 11 priority pharmaceuticals, namely, atenolol, azithromycin, carbamazepine, diclofenac, ibuprofen, erythromycin, metoprolol, ofloxacin, propranolol, sulfamethoxazole, and trimethoprim. The most mutagenic compounds were found to be ß-blockers. In parallel, the photolabile pharmaceuticals were assessed for their mixture effects on mutagenicity (tk assay), estrogenicity (T47D- KBluc assay), and gene expression (microarrays). Interestingly, the mixtures were mutagenic at the µg/L level, indicating a synergistic effect. None of the photolysed mixtures were statistically significantly estrogenic. Gene expression profiling revealed effects related mainly to certain pathways, those of the p53 gene, mitogen-activated protein kinase, alanine, aspartate, and glutamate metabolism, and translation-related (spliceosome). Fourteen phototransformation products are proposed based on the m/z values found through ultra-performance liquid chromatography-tandem mass spectrometry analysis. The transformation routes of the photolysed mixtures indicate a strong similarity with those obtained for each pharmaceutical separately. This finding reinforces the view that transformation products are to be expected in naturally occurring mixtures. Environ Toxicol Chem 2016;35:2753-2764. © 2016 SETAC.


Assuntos
Antagonistas Adrenérgicos beta/toxicidade , Misturas Complexas/toxicidade , Mutagênicos/toxicidade , Preparações Farmacêuticas/análise , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Antagonistas Adrenérgicos beta/análise , Antagonistas Adrenérgicos beta/efeitos da radiação , Animais , Linhagem Celular Tumoral , Misturas Complexas/análise , Misturas Complexas/efeitos da radiação , Perfilação da Expressão Gênica , Humanos , Camundongos , Análise em Microsséries , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutagênicos/análise , Mutagênicos/efeitos da radiação , Ofloxacino , Preparações Farmacêuticas/efeitos da radiação , Fotólise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/efeitos da radiação
14.
Sci Total Environ ; 557-558: 652-64, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27037887

RESUMO

Pharmaceutically active compounds (PhACs) have been recently shown to exert phytotoxic effects. The present study explores the uptake, systemic translocation, and abiotic stress responses and detoxification mechanisms induced by the exposure of alfalfa plants grown in sand under greenhouse conditions to four common, individually applied PhACs (10µgL(-1)) (diclofenac, sulfamethoxazole, trimethoprim, 17a-ethinylestradiol) and their mixture. Stress physiology markers (lipid peroxidation, proline, H2O2 and NO content, antioxidant activity assays) and gene expression levels of key plant detoxification components (including glutathione S-transferases, GST7, GST17; superoxide dismutases, CuZnSOD, FeSOD; proton pump, H(+)-ATP, and cytochrome c oxidase, CytcOx), were evaluated. PhACs were detected in significantly higher concentrations in roots compared with leaves. Stress related effects, manifested via membrane lipid peroxidation and oxidative burst, were local (roots) rather than systemic (leaves), and exacerbated when the tested PhACs were applied in mixture. Systemic accumulation of H2O2 in leaves suggests its involvement in signal transduction and detoxification responses. Increased antioxidant enzymatic activities, as well as upregulated transcript levels of GST7, GST17, H(+)-ATPase and CytcOx, propose their role in the detoxification of the selected PhACs in plants. The current findings provide novel biochemical and molecular evidence highlighting the studied PhACs as an emerging abiotic stress factor, and point the need for further research on wastewater flows under natural agricultural environments.


Assuntos
Medicago sativa/fisiologia , Poluentes do Solo/toxicidade , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Medicago sativa/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Superóxido Dismutase/metabolismo
15.
Electrophoresis ; 37(7-8): 1101-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26333847

RESUMO

This paper reports the development and validation of a new method based on ultra-performance LC coupled to MS/MS for the simultaneous determination of four cholesterol oxidation products (COPs) in foodstuffs in only 4.1 min. The COPs were detected by ESI in positive-ion mode with multiple reaction monitoring, and the mass spectrometric conditions were optimized in order to increase sensitivity. The developed method was validated in terms of linearity, precision, LODs, and LOQs. Recoveries of the extraction process ranged from 86 to 98.5% when the samples were fortified at 100, 500, and 1500 ng/mL. The applicability of the method was confirmed by analyzing different food samples. Considering the paucity of data regarding the content of COPs in Cypriot foods, particular attention was devoted, for the first time, to the determination of the profile of the main COPs in widely consumed, traditional Cypriot foodstuffs (halloumi cheese, hiromeri, snails, etc.).


Assuntos
Colesterol/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Chipre , Laticínios/análise , Limite de Detecção , Modelos Lineares , Carne/análise , Oxirredução , Coelhos , Reprodutibilidade dos Testes , Caramujos , Suínos
16.
Photochem Photobiol Sci ; 14(3): 528-35, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25338014

RESUMO

In this work, the degradation of the azo dye methyl orange in model aqueous solutions by UVC light-induced persulfate oxidation was studied. Five operating parameters that may influence the decolorization kinetics were evaluated, namely, methyl orange (MO) (5-50 mg L(-1)) and sodium persulfate (SPS) (50-150 mg L(-1)) concentration, reaction time (up to 60 min), (un-buffered) solution pH (3-9) and the addition of NaCl (0-500 mg L(-1)). The process was simulated, applying and comparing two methodologies, namely two-level factorial design and an artificial neural network (ANN). It was found that MO concentration is the most influential parameter, followed by the reaction time and SPS concentration, while the effects of solution pH and the addition of sodium chloride are statistically less significant; this order of significance was predicted by both methodologies. The ANN can simulate the process more accurately (i.e. in terms of R(2), mean square error (MSE) and residuals) than factorial design, although it needs significantly larger sets of data and longer computational time.

17.
Environ Monit Assess ; 186(8): 4857-70, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24687690

RESUMO

An extensive field survey was employed for assessing the impacts of long-term wastewater irrigation of forage crops and orange orchards in three suburban agricultural areas in Cyprus (areas I, II, and III), as compared to rainfed agriculture, on the soil geochemical properties and the bioaccumulation of heavy metals (Zn, Ni, Mn, Cu, Co) to the agricultural products. Both ryegrass fields and orange orchards in areas I and II were continuously wastewater irrigated for 10 years, whereas clover fields in area III for 0.5, 4, and 8 years. The results revealed that wastewater reuse for irrigation caused a slight increase in soil salinity and Cl(-) content in areas I and II, and a remarkable increase, having strong correlation with the period in which wastewater irrigation was practiced, in area III. Soil salinization in area III was due to the high electrical conductivity (EC) of the wastewater applied for irrigation, attributed to the influx of seawater to the sewage collection network in area III. In addition, the wastewater irrigation practice resulted in a slight decrease of the soil pH values in area III, while a subtle impact was identified regarding the CaCO3, Fe, and heavy metal content in the three areas surveyed. The heavy metal content quantified in the forage plants' above-ground parts was below the critical levels of phytotoxicity and the maximum acceptable concentration in dairy feed, whereas heavy metals quantified in orange fruit pulp were below the maximum permissible levels (MPLs). Heavy metal phytoavailability was confined due to soil properties (high pH and clay content), as evidenced by the calculated low transfer factor (TF).


Assuntos
Agricultura/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Eliminação de Resíduos Líquidos/métodos , Chipre , Monitoramento Ambiental , Esgotos/química , Águas Residuárias/química , Águas Residuárias/estatística & dados numéricos
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