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1.
Environ Res ; 211: 112971, 2022 08.
Article in English | MEDLINE | ID: mdl-35276188

ABSTRACT

The contamination of water by pharmaceutical pollutants is a major issue these days due to excessive use of these ingredients in modern life. This study evaluated the adsorption and effectiveness of a low-cost composite prepared from heavy sugarcane ash (HSA) fused with polyethylene terephthalate (PET) and functionalized with iron (Fe3+) in a dynamic system through a fixed-bed column. The solution of synthetic drugs was prepared and placed in a reservoir, using a peristaltic pump the solution is run onto the fixed bed column at a flow rate of 2 mL min-1. Saturation time and adsorption capacity were evaluated by centrifugation and extraction after a regular interval of 2 h from the adsorption column. The samples were analyzed using high-performance liquid chromatography (HPLC) and the data was modeled for quantification. For DIC removal, an adsorption capacity of 324.34 µg. g-1 and a saturation time of 22 h were observed, while the adsorption capacity of NAP was 956.49 µg. g-1, with a saturation time of 8 h. Thus, the PETSCA/Fe3+ adsorbent proved to be quite efficient for removing the pharmaceutical pollutants, with a longer period of operation for DIC removal. These findings suggested that a highly efficient bed column made from a less expensive waste material and could be used to remove hazardous pharmaceutical contaminants.


Subject(s)
Saccharum , Water Pollutants, Chemical , Water Purification , Adsorption , Diclofenac , Naproxen/analysis , Pharmaceutical Preparations , Polyethylene Terephthalates , Water/chemistry , Water Pollutants, Chemical/analysis , Water Purification/methods
2.
Chemosphere ; 289: 133222, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34902391

ABSTRACT

Every year, a considerable volume of medications is consumed. Because these medications are not entirely eliminated in the sewage treatment plants and impact the surface waterways, the environmental pollution problem arises. This study objective was to evaluate the possibility of using an absorbent material made with of polyethylene terephthalate and sugarcane bagasse ash functionalized with iron oxide (PETSCA/Fe3+) in the removal of naproxen from water. The feasibility of having viable features in becoming an efficient adsorbent was first determined. The batch test was performed, allowing the dose effect, adsorption kinetics, and isotherm models to be evaluated. The determination of naproxen (NAP) concentration in water was analyzed on a high-performance liquid chromatograph and Langmuir method best represented the adsorption isotherm model. PETSCA/Fe3+ adsorbent material demonstrated potential in the naproxen removal at a low cost. The batching process was satisfactory, with 0.30 g of composite being the optimum fit for the system. The adsorption kinetics was determined and described by the pseudo second order model, with an average correlation coefficient (R2) of 0.974. The adsorption system model was best represented by the Langmuir isotherm curve. Moreover, adsorption in the presence of H2O2 had a positive impact on the process, removing 81.9% of NAP, whereas the process without H2O2 did not remove more than 62.0% of NAP. Therefore, because of its good qualities for NAP removal, PETSCA/Fe3+ is recommended as adsorbent material, primarily in small-volume water filtration systems.


Subject(s)
Water Pollutants, Chemical , Water Purification , Adsorption , Ferric Compounds , Hydrogen Peroxide , Hydrogen-Ion Concentration , Kinetics , Naproxen , Water , Water Pollutants, Chemical/analysis
3.
Environ Technol ; 42(13): 2095-2111, 2021 May.
Article in English | MEDLINE | ID: mdl-31714186

ABSTRACT

This work objective was to evaluate batch adsorption processes using polyethylene terephthalate composite (PTC) material, sugarcane bagasse ash (SBA) functionalized with iron oxide (Fe3+) (PTCSBA/ Fe3+) in the adsorption of 1000 µg  L-1 of diclofenac sodium (DIC) in synthetic solution, simulating water supply. The batch test was started by determining the adsorbent mass (0.1, 0.2, 0.3, 0.4 and 0.5 g) to remove 1000 µg L-1 of DIC, followed by the adsorption kinetics and adsorption isotherm assays, evaluating the reaction rate and adsorption capacity, respectively. The PTCSBA/ Fe3+ mass that had the best efficiency in the DIC removal was 0.3 g, the pseudo second-order kinetic model (PSO) was the one that best fit the study having a determination coefficient (R2) equals to 0.97. The PTCSBA/ Fe3+ has good characteristics for DIC adsorption, achieving a 93% removal rate of sodium diclofenac. The composite is a low-cost adsorbent, 0.08 cents per kilogram of material, becoming a material with satisfactory characteristics for the removal of DIC. Therefore, it is recommended to use PTCSBA/ Fe3+ as adsorbent material in small water filter systems in order to remove DIC due to the low cost of the composite.


Subject(s)
Water Pollutants, Chemical , Water Purification , Adsorption , Diclofenac , Hydrogen-Ion Concentration , Kinetics , Water Pollutants, Chemical/analysis , Water Supply
4.
Chemosphere ; 267: 128888, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33190907

ABSTRACT

Hormones as a group of emerging contaminants have been increasingly used worldwide, which has increased their concern at the environmental level in various matrices, as they reach the water bodies through effluents due to the ineffectiveness of conventional treatments. Here we review the environmental scenario of hormones estriol (E3), 17ß-estradiol (E2), and 17α-ethinylestradiol (EE2), explicitly their origins, their characteristics, interactions, how they reach the environment, and, above all, the severe pathological and toxicological damage to animals and humans they produce. Furthermore, studies for the treatment of these endocrine disruptors (EDCs) are deepened using electrochemical processes as the remediation methods of the respective hormones. In the reported studies, these micropollutants were detected in samples of surface water, underground, soil, and sediment at concentrations that varied from ng L-1 to µg L-1 and are capable of causing changes in the endocrine system of various organisms. However, although there are studies on the ecotoxicological effects concerning E3, E2, and EE2 hormones, little is known about their environmental dispersion and damage in quantitative terms. Moreover, biodegradation becomes the primary mechanism of removal of steroid estrogens removal by sewage treatment plants, but it is still inefficient, which shows the importance of studying electrochemically-driven processes such as the Electrochemical Advanced Oxidation Processes (EAOP) and electrocoagulation for the removal of emerging micropollutants. Thus, this review covers information on the occurrence of these hormones in various environmental matrices, their respective treatment, and effects on exposed organisms for ecotoxicology purposes.


Subject(s)
Endocrine Disruptors , Water Pollutants, Chemical , Animals , Endocrine Disruptors/analysis , Endocrine Disruptors/toxicity , Environmental Monitoring , Estradiol/analysis , Estriol/analysis , Estrogens/analysis , Estrone/analysis , Ethinyl Estradiol/analysis , Ethinyl Estradiol/toxicity , Family Characteristics , Humans , Water , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
5.
J Hazard Mater ; 399: 123094, 2020 11 15.
Article in English | MEDLINE | ID: mdl-32534401

ABSTRACT

This study demonstrates the evaluation between the artificial neural network technique coupled to the genetic algorithm (ANN-GA) and the response surface methodology (RSM) for prediction of Reactive Black 5 (RB5) decolorization by crude enzyme from Pleurotus. sajor-caju. Fungal lignin-modifying enzymes (FLME) were synthesized using pulp wash (PW) as an inducing substrate, and L. cylindrica (L.C) for cell immobilization. When grown in PW, the fungus showed higher Lac activity (126.5 IU. mL-1), whereas when immobilized a higher MnP activity was achieved (22.79 IU. mL-1), but both methods were capable of decolorizing the dye in about 89.4 % and 75 %, respectively. This indicates applicability of PW as an alternative substrate for FLME induction and viability of immobilization for MnP synthesis. For RB5 decolorization, the action of the crude enzyme extract was considered as a function of pH, dye concentration, temperature, and reaction time. The models are well adjusted to predict the efficiency of biodecolorization, with no statistical difference between ANN-GA and RSM, which indicates potential for green enzymes prospecting application in bioprocess industry.


Subject(s)
Azo Compounds , Luffa , Lignin , Naphthalenesulfonates , Neural Networks, Computer
6.
Ecotoxicol Environ Saf ; 198: 110659, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32330790

ABSTRACT

Alternative routes to degrade dyes are of crucial importance for the environment. Hence, we report the electrochemical removal of indanthrene blue by using a boron-doped diamond anode, focusing on the toxicity of the treated solutions. Different operational conditions were studied, such as current density (5, 10, and 20 mA cm-2) and electrolyte composition (Na2SO4, Na2CO3, and NaNO3). Besides, the pH was monitored throughout the experiment to consider its direct influence on the ecotoxicity effects. The highest electrochemical oxidation efficiency, measured as color removal, was seen in the 180 min condition of electrolysis in 0.033 M Na2SO4, applying 20 mA cm-2, resulting in a color removal of nearly 91% and 40.51 kWh m-3 of energy consumption. The toxicity towards Lactuca sativa depends solely on pH variations being indifferent to color removal. While the inhibition concentration (IC50) for Raphidocelis subcapitata increases 20% after treatment (in optimized conditions), suggesting that the byproducts are more toxic for this specific organism. Our data highlight the importance of analyzing the toxicity towards various organisms to understand the toxic effect of the treatment applied.


Subject(s)
Anthraquinones/analysis , Chlorophyta/drug effects , Electrolysis/methods , Lactuca/drug effects , Water Decolorization/methods , Water Pollutants, Chemical/analysis , Anthraquinones/toxicity , Boron/chemistry , Chlorophyta/growth & development , Diamond/chemistry , Electrodes , Lactuca/growth & development , Oxidation-Reduction , Water Pollutants, Chemical/toxicity
7.
Biotechnol Rep (Amst) ; 25: e00411, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32211306

ABSTRACT

This study evaluated simultaneously the raw vinasse degradation, an effluent from the sugar-alcohol industry, the laccase production by Pleurotus sajor-caju and its purification using aqueous two-phase systems (ATPS). To improve laccase production, different concentrations of inducers (ethanol and CuSO4) were added. The higher laccase production promoted an increase of 4-fold using 0.4 mM of CuSO4 as inducer, with maximum enzymatic activity of 539.3 U/L on the 3rd day of fermentation. The final treated vinasse had a decolorization of 92% and turbidity removal of 99% using CuSO4. Moreover, the produced laccase was then purified by ATPS in a single purification step, reaching 2.9-fold and recovered ≈ 99,9 %, in the top phase (PEG-rich phase) using 12 wt% of PEG 1500 + 20 wt% of citrate buffer + enzyme broth + water, at 25 °C. Thus, an integrated process of vinasse degradation, laccase production and purification with potential industrial application was proposed.

8.
Environ Technol ; 41(10): 1307-1321, 2020 Apr.
Article in English | MEDLINE | ID: mdl-30280982

ABSTRACT

After designing and constructing an electrochemical reactor with concentric electrodes and tangential feed (RECT), it is necessary to characterize it and to study its performance. The experimental study of the residence time distribution (RTD) was conducted for flow rates of 2.78 × 10-6 m3 s-1, 8.33 × 10-6 m3 s-1 and 13.9 × 10-6 m3 s-1. According to the values obtained from the Pe number (0.67-1.52), the RECT fits as tubular with great dispersion. The determined empirical correlation (Sh = 18.16 Re0.50 Sc0.33) showed a laminar flow behavior in the range of Reynolds number (Re) between 23 and 117. In order to use RECT in effluent treatment, an electrochemical oxidation study of the Diuron model molecule (Nortox®) was performed to analyze reactor performance in a closed system with total reflux. A decay kinetics of pseudo-first order was associated with the decay of the concentration of diuron and 30% mineralization in 180 min of process were obtained, having a total volume of 4 × 10-3 m3 and an initial concentration of commercial Diuron in 215.83 mg dm-3. Eleven by-products were identified by HPLC-MS analysis and, from this, it was possible to propose a route of degradation of the diuron. From these observations, it can be inferred that the studied electrochemical reactor had applicability in the degradation of recalcitrant compounds, as is the case of commercial diuron. Make some changes in the electrochemical reactor studied and other advanced oxidative processes, such as electro-Fenton, can be associated with the studied system to achieve a better conversion efficiency.


Subject(s)
Herbicides , Water Pollutants, Chemical , Diuron , Electrodes , Hydrogen Peroxide , Oxidation-Reduction
9.
Chemosphere ; 236: 124309, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31344620

ABSTRACT

As it is well known, the textile industry generates a large amount of wastewater with varied composition that need to be treated. In particular, the Sergipe state, in Brazil, is a region that requires attention due the presence of several local textile industries. In this study, the efficiency of electrochemical oxidation (EO) process applied in the samples of Brazilian textile industry effluents previously treated by physical-chemical process coagulation-flocculation (CF) was evaluated by the reduction in TOC parameter and by the ecotoxicity using Lactuca sativa and Raphidocelis subcapitata bioassays. The optimized experiments achieved for the CF ([Al2(SO4)3]0 = 1.5 mg L-1, pH = 6.0, alkalinity = 0.675 mg L-1, [flocculating agent] = 61 mg L-1, rapid mixing = 100 rpm for 1 min, slow stage = 20-60 rpm for 20 min) a reduction of 20% on TOC. The best results obtained for EO was using the DSA electrode (I = 300 mA) reaching a TOC removal efficiency of 82% after an electrolysis time of 180 min. The ecotoxicity experiments indicated that the proposed treatment (CF + EO, I = 300 mA) was effective to decrease the dissolved pollutants presented in the treated samples. In comparison with raw samples, the treatment achieved a reduction of 52% for IC5072h value using R. subcapitata as bioindicator, and a 98% reduction of LC50 (Lactuca sativa).


Subject(s)
Ecotoxicology/methods , Oxidation-Reduction/drug effects , Textile Industry/methods , Water Pollutants, Chemical/chemistry , Flocculation , Industrial Waste/analysis , Water Pollutants, Chemical/analysis
10.
Eng. sanit. ambient ; 22(3): 429-435, mai.-jun. 2017. tab, graf
Article in Portuguese | LILACS | ID: biblio-840420

ABSTRACT

RESUMO Os objetivos deste trabalho foram avaliar a presença e a concentração dos anti-inflamatórios diclofenaco e naproxeno em um córrego urbano localizado no município de Três de Lagoas, Mato Grosso do Sul, que recebe efluente de uma estação de tratamento de esgoto; e verificar a influência da temperatura da água na ocorrência dos fármacos em águas superficiais. Foi realizado monitoramento dos anti-inflamatórios e dos parâmetros temperatura, pH e oxigênio dissolvido na água durante 12 meses consecutivos (outubro de 2008 a setembro de 2009). Foram coletadas amostras de água mensalmente em seis pontos, representando diferentes seções do córrego. As amostras foram submetidas ao processo de extração em fase sólida e analisadas por cromatografia líquida de alta eficiência. Para verificar a influência da temperatura da água na ocorrência dos anti-inflamatórios diclofenaco e naproxeno nos ambientes aquáticos, utilizou-se um modelo de regressão logística do Statistical Analysis System versão 9.0. Os anti-inflamatórios diclofenaco e naproxeno foram detectados nos diferentes pontos monitorados no Córrego da Onça. Os demais parâmetros avaliados neste estudo foram comparados com os padrões de qualidade de água estabelecidos pela Resolução CONAMA nº 357/2005. A maior concentração do diclofenaco foi detectada no ponto localizado à jusante da estação de tratamento de esgoto do município, enquanto a maior concentração de naproxeno foi registrada na foz do córrego. A temperatura da água influencia de forma inversamente proporcional a ocorrência dos dois anti-inflamatórios no córrego, ou seja, quanto maior a temperatura do corpo hídrico, menor a probabilidade de detecção dos fármacos diclofenaco e naproxeno.


ABSTRACT The aims of this study were to evaluate the presence and concentration of the anti-inflammatory drugs diclofenac and naproxen in an urban stream located in Três Lagoas, Mato Grosso do Sul, Brazil, that receives effluent from a wastewater treatment plant; and to evaluate the influence of water temperature in the occurrence of these drugs into surface waters. Monitoring of both anti-inflammatory and the parameters temperature, pH and dissolved oxygen was held in this water body during 12 consecutive months (October 2008 to September 2009). Water samples were collected monthly at six points representing different sections of the stream. The samples were subjected to solid phase extraction procedure and analyzed by high performance liquid chromatography. To check the influence of water temperature on the occurrence of the anti-inflammatory drugs diclofenac and naproxen in aquatic environments, it was used a logistic model of regression, the Statistical Analysis System version 9.0. The anti-inflammatory drugs diclofenac and naproxen were detected at different points in the Stream of Onça. The other parameters evaluated in this study were compared with the water quality standards established by the CONAMA Resolution 357/2005. The highest concentration of diclofenac was detected in the point located downstream of the wastewater treatment plant of the city, while the largest concentration of naproxen was recorded at the mouth of the stream. The water temperature influence, in an inversely proportional way, the occurrence of both anti-inflammatory in the stream, the higher the temperature the lower the water body probability of detection of drug diclofenac and naproxen.

11.
Environ Monit Assess ; 187(6): 379, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26013657

ABSTRACT

The growing use of pharmaceutical drug is mainly due to several diseases in human and in animal husbandry. As these drugs are discharged into waterways via wastewater, they cause a major impact on the environment. Many of these drugs are hormones; in which even at low concentrations can alter metabolic and physiological functions in many organisms. Hormones were found in surface water, groundwater, soil, and sediment at concentrations from nanograms to milligrams per liter of volume--quantities known to cause changes in the endocrine system of aquatic organisms. This study aimed to develop a methodology for hormone detection (estriol, estrone, 17ß-estradiol, 17α-ethinylestradiol, progesterone, and testosterone) on surface and treated water samples. Sample toxicity was assessed by ecotoxicology tests using Daphnia magna. A liquid chromatograph coupled to a mass spectrometer with an electrospray ionization source (LC-ESI-MS/MS) was used for the analysis. The results showed that samples were contaminated by the hormones estriol, estrone, progesterone, 17ß-estradiol, and 17α-ethinylestradiol during the sampling period, and the highest concentrations measured were 90, 28, 26, 137, and 194 ng · L(-1), respectively. This indicates the inflow of sewage containing these hormones at some points in the Piracicaba River in the State of Sao Paulo-Brazil. Results indicated little toxicity of the hormone estriol in D. magna, indicating that chronic studies with this microcrustacean are necessary.


Subject(s)
Drinking Water/analysis , Endocrine Disruptors/analysis , Gonadal Steroid Hormones/analysis , Rivers/chemistry , Water Pollutants, Chemical/analysis , Animals , Brazil , Chromatography, Liquid , Daphnia , Ecotoxicology , Endocrine Disruptors/toxicity , Environmental Monitoring/methods , Estradiol/analysis , Estrone/analysis , Ethinyl Estradiol/analysis , Gonadal Steroid Hormones/toxicity , Humans , Sewage/analysis , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry , Wastewater/chemistry , Water Pollutants, Chemical/toxicity , Water Supply
12.
Pesticidas ; 22: 17-34, jan.-dez. 2012.
Article in Portuguese | LILACS | ID: lil-683603

ABSTRACT

O presente artigo teve como objetivo efetuar revisão de literaturasobre os desreguladores endócrinos. Os tópicos abordados incluíram a caracterização e a classificação dos desreguladores endócrinos, sua ocorrência no ambiente, possíveis efeitos na biota e na saúde humana. De acordo com a pesquisa bibliográfica, ainda existem poucos estudos no Brasil relatando a ocorrência de desreguladores endócrinos no ambiente e seus possíveis efeitos nos seres vivos.Tais trabalhos se concentram em países desenvolvidos, localizados na maioria das vezes em regiões temperadas. Essas pesquisas indicam que mesmo em baixas concentrações, os desreguladoresendócrinos afetam toda a biota e causam prejuízos à saúde humana, interferindo principalmente no sistema reprodutor dos organismos. O estudo dos desreguladores endócrinos torna-se importante para definição de medidas que minimizem sua liberação no ambiente e para o desenvolvimento de metodologias que reduzam ou removamessas substâncias das matrizes ambientais


Subject(s)
Aquatic Environment , Environmental Pollution , Endocrine System Diseases , Hormones , Pesticides
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