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La minería de carbón es una de las actividades predominantes en el departamento del Cesar, Colombia; esta impulsa el crecimiento económico del país. Después del proceso de extracción del mineral, suele utilizarse capas de suelos acopiados y material estéril para formar suelos artificiales, también llamados suelos mineros; estos, por sus condiciones edáficas poseen cierto grado de toxicidad e infertilidad, que restringe el crecimiento y la supervivencia de los organismos en el medio, dando lugar a la formación de áreas desérticas. La rehabilitación de suelos mineros fomenta el restablecimiento de las condiciones adecuadas, permitiéndole a este ofrecer nuevamente algunos bienes y servicios ambientales. El objetivo fue evaluar el efecto del biochar, los hongos formadores de micorrizas arbusculares (HMA) y NPK en la rehabilitación de suelos mineros, y en el crecimiento de la plántula Guazuma ulmifolia a partir de tres ensayos. Inicialmente se hizo un ensayo de germinación, utilizando semillas de Guazuma ulmifolia, suelos mineros y biochar en concentraciones del 0, 1, 5 y 10%; luego se estableció un ensayo a escala vivero en donde se aplicaron cuatro tratamientos que contenían a la plántula, biochar, HMA y NPK, posteriormente se realizó un ensayo a escala campo utilizando cuatro tratamientos con la plántula, biochar y HMA. Los resultados muestran que el biochar en concentraciones de 1 y 5% incrementó significativamente el porcentaje de germinación, la longitud foliar y biomasa de las plantas; además, se halló un porcentaje de infección del 60% en las raíces de la planta por HMA; así mismo, hubo un aumento importante de pH, fósforo, carbono orgánico, glomalina y actividad enzimática en los suelos, también una reducción significativa en la conductividad eléctrica. El uso de biochar y micorrizas mejoró las propiedades de los suelos y estimuló un mayor crecimiento en la plántula, promoviendo así el proceso de rehabilitación.

Se realizó la implementación de un reactor SBR (Sequencing Batch Reactor- por sus siglas en inglés y Reactor Secuencial en Discontinuo - en español) para la remoción de la materia orgánica presente en el agua residual de una empresa de teñido de flores. Se analizaron parámetros fisicoquímicos para evaluar la eficiencia del proceso y seguimiento de la biomasa mediante pruebas de sedimentabilidad y observaciones al microscopio. El sistema SBR fue operado usando una fase de llenado estática durante 2 h, una etapa de reacción durante 8 h (4 h de aireación y 4 h de mezcla) y finalmente una etapa de sedimentación durante 2 h, para un total de 12 horas por ciclo y 2 ciclos al día, y se evaluaron dos colorantes azo (C1 y C2) ampliamente usados en la industria del teñido de flores, variando temporalmente la concentración de la materia orgánica en términos de DQO con valores de 3,0 g /L.d y 7,0 g /L.d. Los resultados experimentales y el análisis estadístico permitió analizar el comportamiento del reactor SBR, concluyendo que ambos colorantes se comportaron estadísticamente iguales en la remoción del carbono orgánico total (COT), con un valor promedio de remoción 92,02% para C1 y 94,60% para C2 con una carga de 3,0 g DQO/L.d y 96,69% para C1 y 98,30% para C2 con una carga de 7,0 g DQO/L.d. La biomasa presentó un IVL bajo, indicando una buena sedimentabilidad tanto para los ensayos llevados a cabo con C1 como C2. Finalmente, los microorganismos identificados en la biomasa permitieron corroborar la eficiencia del sistema de tratamiento, dado que abundaron los rotíferos y ciliados fijos con C1 y ciliados libres con C2, los cuales son indicadores de una buena eficiencia en los procesos de tratamiento y a su vez, indicadores de edades de lodos elevadas, lo que contrasta con la edad de lodos empleada en este estudio (θc = 15 d).

El desarrollo industrial ha generado la creación de nuevos productos que han mejorado la calidad de vida. De tal forma, se ha impulsado el consumo de fármacos, cosméticos, artículos de limpieza y de cuidado personal, entre otros. Éstos denominados contaminantes emergentes han sido de uso frecuente en las últimas décadas ocasionando una fuerte presión para los hábitats acuáticos y considerándose como factores de riesgo para la salud de los seres vivos. Un ejemplo es el triclosán (TCS), reconocido por su acción fungicida y presente en productos de aseo como antibacteriales, cuidado personal, jabones líquidos y enjuagues bucales. Desafortunadamente se ha encontrado en aguas crudas y residuales teniendo interacción con los ecosistemas acuáticos e incidiendo en la calidad de vida de los individuos, alterando funciones metabólicas y en consecuencia a la cadena trófica por efecto de bioacumulación. De tal forma, en esta investigación se evaluó el efecto del triclosán en la movilidad espermática de machos sexualmente maduros de Oreochromis spp. que fueron sometidos a un diseño experimental con tres factores: concentración de triclosán (0, 50, 120 y 190 µg/L), pH (7 y 9) y tiempo de exposición (0, 3 y 7 días). Los resultados evidenciaron una disminución significativa en la movilidad rápida y por lo tanto un aumento significativo para algunos tratamientos en la movilidad media y lenta. Los resultados permiten concluir que la interacción entre los factores evaluados pudo incidir en la alteración de la estructura celular espermática y a nivel mitocondrial disminuyendo su movilidad por una baja síntesis de adenosin trifosfato.

The textile industry is a generator of high volumes of waste water with a high content of pollutants such as azo dyes, which are recalcitrant and persistent in the environment, these ones have been of interest in the last decades for the entities in charge of the care of the environment. This study evaluated the ability to discolor of reactive black 5 (NR5) by a consortium and the microorganisms that constitute Rhodotorula mucilaginosa, Galactomyces pseudocandidum and Escherichia coli free and immobilized in calcium alginate, coffee husks and bagasse of sugar cane. The results show discoloration was evidenced, where the highest percentage corresponds to G. pseudocandidum (90,05%) and the lowest to R. mucilaginosa (79,31%). When comparing the percentages of discoloration between the free microorganisms and the immobilization matrices, it is observed that the former exhibit the highest percentages of discoloration. In addition, there are no significant differences between using cane bagasse or coffee husks as immobilization matrix.

Este trabajo evaluo el efecto de los compuestos liberados durante la renovacion de raices de cuatro plantas: Avena sativa, Brachiaria decumbens, Brassica juncea y Medicago sativa, en la degradacion de seis congeneres de bifenilos policlorados (PCBs) en un suelo contaminado con Aroclor 1260. Los ensayos se realizaron en microcosmos con 20 g de suelo a los cuales se les adicionaron triturados de raices de las plantas cultivadas en suelo contaminado con PCBs y se usaron como controles: suelo con bifenil y con acido salicilico y suelo sin adiciones. Los microcosmos se incubaron durante 45 dias en condiciones controladas. Al finalizar la incubacion se tomaron muestras para la determinacion de la concentracion de los PCB 44, PCB66, PCB118, PCB138, PCB153, PCB180 y PCB170, del gen BphA1 y determinacion de la hidrolisis de fluoresceina. Tambien se analizaron los extractos obtenidos de la raiz para identificar metabolitos secundarios. En los microcosmos con Brassica juncea y con bifenil se observo disminucion de la concentracion de los PCB66, 118 y 138. Asi mismo, en estos microcosmos se observo mayor concentracion del gen BphA1 y de fluoresceina. Los analisis de los extractos de raiz permitieron identificar diferentes metabolitos secundarios asociados con las plantas, siendo los extractos de la planta Brassica juncea donde se detecto mayor numero de metabolitos. Los resultados permitieron comprobar el efecto de los compuestos liberados por las raices de ciertas plantas sobre las poblaciones microbianas del suelo con capacidad de degradar PCBs.

Ethylparaben (Eth-PB) is one of the most used parabens for preservation of many personal care products and food. However, a number of scientific studies have indicated that this compound could interfere with the endocrine or hormonal system of different living beings, which along with data about its presence in different water bodies generates the necessity of seeking alternatives to minimize the potential negative effect of this situation. In this way, removal of Eth-PB using heterogeneous photocatalysis with TiO2, hydrogen peroxide and light radiation (solar spectrum: wavelength >290 nm) was assessed, considering the individual effects of different operational parameters like the catalyst and H2O2 dosages, the pH and the pollutant initial concentration. According to this, conditions that, under the experimental range, promote a higher paraben elimination were established. Tests were carried out at lab-scale using a photo-simulator equipped with a Xenon lamp, and at pilot scale (volume treated ∼100 L) using a compound parabolic collector and direct solar light radiation. In both cases, more than a 80% of substrate elimination was reached in less than 6 h of reaction, demonstrating the effectiveness of the photocatalytic system to remove this kind of compounds. Additionally, a significant reduction of the total organic carbon present in the solutions, and an increment of the biodegradability of the samples were appreciated. Finally, some of the by-products generated during the contaminant removal were identified.

Cyanotoxin contamination is of special interest in water bodies, especially those for human use, due to the various negative effects that blooms of potentially toxic cyanobacteria can cause on human health. Given the recreational and supply importance of the Abreo - Malpaso, Peñol - Guatapé and Playas reservoirs in the Department of Antioquia, Colombia. This study has estimated the biomass of the planktonic cyanobacteria, their geometric biovolume, the surface volume ratio (S / V) and the maximum linear dimension (MLD), during four sampling seasons in three different stations for each of these bodies. Water. We have identified from the Cyanophyta division with the production of cyanotoxins, the Microcystis complex and generates Woronichinia, Aphanocapsa and Oscillatoria, as well as the species Radiocystis fernandoi. When applying the nonparametric Kruskal - Wallis test, no significant differences were found between the studied reservoirs (p> 0.05); however, the Peñol - Guatapé reservoir presented the highest algae biomass and density of cyanobacteria, therefore, according to the levels of risk posed for the reservoirs studied and according to the morphological characteristics of these organisms, this reservoir presents a High Medium risk level in relation to the presence and morphology of the cyanobacteria, while the Abreo-Malpaso and Playas reservoirs are associated with a Medium Low risk. It is suggested to establish control and prevention measures to avoid a massive development of cyanobacteria, a possible presence of cyanotoxins and serious affectations in humans and animals. El desarrollo masivo de cianobacterias y la contaminación por cianotoxinas constituyen una problemática ambiental de especial interés en los sistemas acuáticos, debido a los diversos impactos negativos que los florecimientos (blooms) de cianobacterias pueden ocasionar. Dada la importancia recreacional y de abastecimiento de los embalses Abreo - Malpaso, Peñol - Guatapé y Playas, ubicados en el oriente de Antioquia - Colombia, en este estudio, se estimó la densidad de cianobacterias planctónicas y otros organismos del fitoplancton, así como el biovolumen geométrico, la relación superficie volumen (S/V) y la dimensión lineal máxima (DLM), a través de cuatro muestreos, en tres estaciones, para cada uno de los embalses. Se identificaron, dentro del phylum Cyanobacteria, con potencial de producción de cianotoxinas, el complejo Microcystis, los géneros Woronichinia, Aphanocapsa y Oscillatoria y la especie Radiocystis fernandoi. Al aplicar la prueba no parámetrica Kruskal – Wallis, no se encontraron diferencias significativas entre los embalses estudiados (p>0,05); sin embargo, el embalse El Peñol – Guatapé presentó la mayor biomasa algal y densidad de cianobacterias, por lo que, según los niveles de riesgo planteados para los embalses estudiados y de acuerdo con las características morfológicas de estos organismos, este embalse presenta un nivel de riesgo Medio Alto con relación a la presencia y morfología de las cianobacterias, mientras que los embalses Abreo – Malpaso y Playas están asociados a un riesgo Medio Bajo. Se sugiere establecer medidas de control y de prevención, con el fin de evitar un desarrollo masivo de cianobacterias, una potencial presencia de cianotoxinas y afectaciones graves a seres humanos y animales. Incluye referencias bibliográficas

RESUMEN: En los ecosistemas acuáticos se monitorea el agua para determinar sus variaciones espacio-temporales, generando grandes y complejas matrices de datos que requieren herramientas que ayuden en la interpretación de los mismos, para que los administradores de los recursos hídricos puedan informar a la sociedad el deterioro de estos y tomar medidas correctivas. El presente artículo es una revisión de tema cuyo objetivo es el examen de técnicas estadísticas multivariadas usadas para examinar la variabilidad espacio-temporal de la calidad del agua. En él se presentan diversas técnicas como el análisis factorial, que se usa con el fin de disminuir la dimensionalidad de los datos y construir factores subyacentes o variables latentes que generen las variables observadas, estos factores pueden usarse e interpretarse como índices de calidad del agua construidos a partir de los datos recolectados; también se presenta en análisis de clúster y el análisis discriminante que se usan comúnmente para estudiar la variabilidad espacial, estudiando similaridades entre períodos o estaciones de muestreo, estas tres técnicas se usan comúnmente con fines exploratorios; para objetivos más complejos como el modelamiento y la predicción, se presentan los modelos jerárquicos, de regresión múltiple y de ecuaciones estructurales. Para todos los métodos se presenta su funcionalidad y aplicabilidad y se ilustran usando casos de estudio. Esta revisión describe cómo estos métodos pueden utilizarse con miras a estudiar la calidad del agua con el fin de monitorear espacial y temporalmente la variabilidad de las medidas tomadas. ABSTRACT: In aquatic ecosystems is monitored the water to determine their space-temporary variations, generating large and complex arrays of data that require tools that assist in the interpretation thereof, for managers of water resources can inform society the deterioration of these and take corrective action. This review is a revision of multivariate statistical techniques used to examine the spatial and temporal variability of water quality. We consider few techniques like Factor Analysis, which is used in order to reduce the dimensionality of the data and build underlying latent variables or factors that produce the observed variables, these factors can be used as water quality indexes built from the data collected; we also consider cluster and discriminant analysis than is commonly used to study the spatial variability and studying similarities between periods or sampling stations, these three techniques are commonly used for exploratory purposes; for more complex goals such as modeling and prediction, hierarchical models, Multiple Regression and Structural Equations are presented. For all methods, we present their functionality and usability methods and illustrated using case studies. This review describes how these methods can be used in order to study water quality for monitoring spatial and temporal variability of the measures taken.

Benzophenone-3 (BP3) is one of the most used UV filters. Its disruptive effect on the endocrine system of different living beings has been demonstrated by several research groups. Present work addresses on a photocatalytic degradation of BP3 using particles of titanium dioxide in aqueous solutions considering the effect of operating parameters such as pH, catalyst and pollutant initial concentrations, and the presence of hydrogen peroxide, acetonitrile and isopropanol in the solution. In this way, a face centered, central composite design was carried out for the identification of significant factors or interactions that allow the determination of the conditions under which the pollutant suffers the highest rates of degradation. A solution initial pH of 9.0, a TiO2 concentration of 1.184 g L(-1) and an H2O2 concentration of 128.069 mg L(-1) were established as the optimal conditions for the substrate removal. In aqueous solutions and low concentrations of the pollutant (

Benzophenone-3 (BP3) and methylparaben (MPB) are two emerging pollutants, whose endocrine disrupting activity on different living beings has been reported. Therefore, removal of these pollutants from aqueous samples using photo-Fenton technology was assessed. Effects of Fe2+ and H2O2 initial concentrations on pollutants photo-degradation were analyzed and a face centered, central composite design was carried out for determining the optimal conditions, in the evaluated range, that conducted to higher substrate elimination. Results indicated that Fe2+ and H2O2 initial concentration and the interaction between them affect significantly the process. In addition, experiments varying BP3 and MPB initial concentrations showed that elimination rate increases with an increase in the substrate initial concentration and a pseudo-first-order kinetic can be used to describe pollutants degradation. Under optimal conditions compounds were eliminated totally after 120 min of treatment. Dissolved organic carbon studies illustrated that more than 60% of contaminants were mineralized and biodegradability analysis indicated that this factor increased gradually during 300 min of photo-Fenton treatment.

RESUMEN Introducción. La materia orgánica presente en el agua de abastecimiento puede ocasionar problemas a las plantas de potabilización, como alteración en las propiedades organolépticas del agua, aumento en los costos de potabilización e incrementos en la formación de subproductos de la desinfección. Objetivo. Evaluar la pre-oxidación como una alternativa para mejorar la remoción de carbono orgánico disuelto (COD) y/o disminuir la formación de trihalometanos durante los procesos de potabilización. Materiales y métodos. Se realizaron experimentos mediante un ensayo de test de jarras, en los que se evaluó la eficiencia de dos coagulantes (hidroxicloruro de aluminio y sulfato de aluminio) y de dos agentes oxidantes (peróxido de hidrógeno y dióxido de cloro) para la remoción de COD y la diminución de la formación de trihalometanos como subproducto de la desinfección con hipoclorito de sodio. También se evaluó el cambio en la turbiedad, color, pH y UV254. Resultados. En términos de remoción de COD, existe una diferencia significativa (p = 0,033) entre la utilización sulfato de aluminio e hidroxicloruro de aluminio, siendo el último más eficiente. Se encontró que la pre-oxidación mejora la remoción de color y turbiedad, y que solo con el peróxido de hidrógeno se comprobó un incremento en remoción de COD. Conclusiones. La pre-oxidación con H2O2 en los procesos de potabilización es una alternativa viable para remover materia orgánica no húmica o hidrófila. Los valores de trihalometanos no superaron los límites permisibles en Colombia y EE. UU., los cuales son 200 μg/L y de 80 μg/L, respectivamente. ABSTRACT Introduction. Organic matter in drinking water can cause problems to the purification plants, such as changes in the water's organoleptic properties, an increase of the purification costs and increases in the disinfection byproducts. Objective. Evaluate pre-oxidation as an alternative to improve the removal of disolved organic carbón (DOC) and/or reduce the formation of trihalomethanes during the purification processes. Materials and methods. Experiments were carried out by means of a jar test in which the efficiency of two coagulants (aluminum hydroxychloride and aluminum sulphate) and two oxidation agents (Hydrogen peroxide and chlorine dioxide) to remove DOC and reduce trihalomethanes as a byproduct of the disinfection with sodium hypochlorite. Turbidity, color, pH and UV254 changes were also assessed. Results. In terms of DOC removal, there is a significant difference (p = 0,033) vetween the use of aluminum sulphate and aluminum oxychloride, and the latter is more efficient. Pre-oxidation improves the color removal and the turbidity, and only with hydrogen peroxide an increase in the DOC removal was proved. Conclusions. Pre-oxidation with H2O2 in purification processes is a feasible alternative to remove not humic and hjydrophilic organic matter. The trihalomethanes' values were not above those allowed in Colombia and USA, 200 µg/L and 80 µg/L, respectively. RESUMO Introdução. A matéria orgânica presente na água de abastecimento pode ocasionar problemas nas plantas de potabilização, como alteração nas propriedades organolépticas da água, aumento nos custos de potabilização e incrementos na formação de sub-produtos da desinfecção. Objetivo. Avaliar a pré-oxidação como uma alternativa para melhorar a remoção de carbono orgânico dissolvido (COD) e/ ou diminuir a formação de trihalometanos durante os processos de potabilização. Materiais e métodos. Se realizaram experimentos mediante um ensaio de test de jarras, nos que se avaliou a eficiência de dois coagulantes (hidroxicloruro de alumínio e sulfato de alumínio) e de dois agentes oxidantes (peróxido de hidrogeno e dióxido de cloro) para a remoção de COD e a diminuição da formação de trihalometanos como sub-produto da desinfecção com hipoclorito de sódio. Também se avaliou a mudança na turvação, cor, pH e UV254. Resultados. Em termos de remoção de COD, existe uma diferença significativa (p = 0,033) entre a utilização sulfato de alumínio e hidroxicloruro de alumínio, sendo o último mais eficiente. Se encontrou que a pré-oxidação melhora a remoção de cor e turvação, e que só com o peróxido de hidrogeno se comprovou um incremento em remoção de COD. Conclusões. A pré-oxidação com H2O2 nos processos de potabilização é uma alternativa viável para remover matéria orgânica não húmica ou hidrófila. Os valores de trihalometanos não superaram os limites permissíveis na Colômbia e E.U.A, os quais são 200 μg/L e de 80 μg/L, respectivamente.

This paper reports the results of an experimental work on sonochemical degradation of benzophenone-3 (BP3), one of the most commonly used ultraviolet (UV) filters whose disruptive effect on the endocrine system of various living beings has been demonstrated. Ultrasound irradiation is a promising advanced oxidation technology that has received considerable interest as an alternative for degradation of persistent organic pollutants through hydroxyl free radicals that are generated from the cavitation bubbles implosion. Taking into account the potential risk due to the presence of BP3 in the environment and its possible removal using ultrasound, the effect of operating parameters such us ultrasonic applied power, pollutant initial concentration, pH, the presence of gases (including ozone), inorganic anions and alcohols on the substrate removal was investigated. During sonochemical treatment, a higher pollutant degradation rate was achieved by increasing the power in a range of 40.2–80.1 W. Likewise, at lower benzophenone-3 initial concentrations, higher extents of degradation were observed, which could be explained by a heterogeneous kinetics model. Acidic pH enhanced the pollutant initial degradation by 21 %. Oxygen, ozone and bicarbonate ions affected positively the benzophenone-3 removal, while nitrogen, nitrate and chloride anions inhibited it. Measurements of concentration of hydroxyl free radicals indicated that by promoting OH. radical formation, the pollutant elimination rate can be increased.

Resumen Los taninos son el segundo grupo de compuestos fenólicos de las plantas más abundantes en la naturaleza y son usados como materia prima en diversos procesos industriales, entre los cuales el más representativo es el teñido del cuero animal. El ácido tánico, un tanino hidrolizable utilizado en éste proceso, puede degradarse por vía biológica, mediante hidrólisis enzimática por la tanasa (EC 3.1.1.20). Para evaluar la capacidad degradadora de taninos y sus condiciones óptimas utilizando microorganismos aislados del proceso de curtiembre, se siguieron técnicas de enriquecimiento y siembra directa en placa, logrando el aislamiento de microorganismos tanino-resistentes, sometidos posteriormente a ensayos de concentración mínima inhibitoria (CMI) llegando hasta 0,4% v/v de ácido tánico. Finalmente, se identificó molecularmente a Bacillus licheniformis como la cepa con mayor capacidad degradadora a pH 7, 35 °C y 90 r. p. m. Abstract Tannins are the phenolic compounds most abundant in nature, used as raw material in several industrial processes like tanning leather. Tannic acid is a hydrolyzable tannin used in tannery, which can be degraded by a biological enzymatic hydrolysis using tannase. To evaluate the capacity and optimal conditions of tannin degradation using microorganisms isolated from a tannery, we used an enrichment technique and plate culture. We obtained the isolation of tannin-resistant bacteria, that were subjected to minimum inhibitory concentration tests (MIC), retaining 0,4% v/v tannic acid. Finally, Bacillus licheniformis was identified as the bacteria with the major capacity of degradation in growth conditions of pH 7, 35 °C and 90 r. p. m.

Los contaminantes organicos emergentes conforman un grupo de sustancias muy heterogeneas, cuya caracteristica en comun es que causan efectos negativos sobre los organismos acuaticos, por lo que deben de ser eliminados del ambiente. Lamentablemente, los procesos convencionales con los que operan las plantas de tratamiento de aguas residuales, especialmente los de tipo biologico, son ineficientes en la remocion de estas sustancias. Por este motivo, se hace necesaria la evaluacion y optimizacion de tratamientos mas eficaces, entre los que se encuentran los procesos de oxidacion avanzada y de filtracion por membranas. Sin embargo, ambas tecnicas presentan inconvenientes que pueden limitar la aplicacion individual de las mismas, de modo que podria proponerse la combinacion de dichas tecnologias con procesos biologicos como mejor solucion para tratar las aguas residuales contaminadas con contaminantes organicos emergentes.

SBR (Sequencing Batch Reactor) treatment systems are made up of an artificial ecosystem where they develop the microorganisms under controlled and limited conditions, in which the pH, organic load and oxygen within the reactor vary spatially and in time. This causes the microbial population to be neither uniform nor constant and therefore reflects the conditions to which they have been exposed during the treatment system. Nitrifying and denitrifying bacteria in a SBR pilot system were monitored over 252 days, using two types of wastewater in the treatment; one with a high amount of organic matter and the other with a high amount of ammonium, both originating from a meat product processing plant. The two types of wastewater were mixed in different proportions with the aim of varying the organic and ammoniacal loading in the influent, thus allowing the most suitable conditions for obtaining high removal efficiencies in the combined treatment of organic matter and ammonia to be determined. The results showed efficiencies of 99%, 98% and 71% in CODF, BOD5 and NH4+–N, respectively, and a microbial density of about 2.35 × 107 MPN/100 mL for nitrifying bacteria and 2.25 × 107 MPN/100 mL for denitrifying bacteria.

Ethylparaben (EPB) has been classified by different research groups as a potential endocrine-disrupting chemical, implying that it can potentially interfere with the normal balance of the endocrine system of living beings, which with its presence in different effluents, including drinking water, generates the need to seek methods that allow its removal from different water bodies. Advanced oxidation processes have been employed widely to remove organic compounds from different matrices. In this way, Fenton technology (process based on the reaction between ferrous ions and hydrogen peroxide) has been able to degrade different substrates, but due to the Fe2+ requirements to carry out the reaction optimally, combination of the conventional Fenton process with visible light radiation (photo-Fenton) is an alternative used in the treatment of pollution due to the presence of chemicals. In this way, the effectiveness of photo-Fenton on EPB degradation was assessed using a face-centered central composite experimental design that allowed assessment of the effects of Fe2+ and H2O2 initial concentrations on process. In general, results indicated that after 180 min of reaction almost all EPB was eliminated, the dissolved organic carbon in solution was reduced and the sample biodegradability index was increased.

The removal of natural organic matter (NOM) from surface water sources was evaluated by a pilot ultrafiltration plant through 3 different treatment processes: UF, PAC/UF and PAC/C-S/UF. For UF, the ultrafiltration plant was used as the only treatment. For PAC/UF, tests were performed with powdered activated carbon (PAC) as pre-treatment to the ultrafiltration membrane. For the PAC/C-S/UF hybrid treatment process, adsorption with PAC and coagulation-sedimentation with aluminum sulphate as a coagulant was used as pre-treatment. The results indicated that the best hybrid treatment process was PAC/C-S/UF, since it maintained a stable transmembrane pressure (TMP) of around 0.5 bar in the operating time, while in the this process the flow remained constant at about 227 L/(m2h). In addition, with this process, the highest removal efficiencies were obtained for the NOM parameters evaluated. Coagulation pre-treatment improved the removal of NOM in comparison with PAC and UF as the only treatment. The results showed that both hydrophobic and hydrophilic organic compounds could be removed by the action of the coagulant. When further comparing the increased removal rates of the hydrophobic material (HoM) and hydrophilic material (HiM) fractions, it was observed that the hydrophobic organic chromophores could be removed by coagulation more easily than the hydrophilic organic chromophore compounds. The molecular weight distribution (MWD) was evaluated, indicating that the PAC/C-S/UF treatment successfully removed medium-high molecular weight (MW) compounds (> 1701 Da), but the removal efficiency of medium-low MW compounds (≤ 1701 Da) began to decrease as the compounds had lower MW.DOI: http://dx.doi.org/10.5755/j01.erem.72.3.12906

Methylparaben (MePB) is an organic compound employed mainly in the manufacture of different personal care products. However, it has been recently listed as a potential endocrine disrupter chemical. Therefore, the main objective of this work was to evaluate the degradation of MePB in aqueous solutions using heterogeneous photocatalysis with TiO2 and hydrogen peroxide. In this way, effects of pH and the initial concentrations of catalyst, H2O2, and pollutant on treatment were analyzed. A face centered, central composite design was used for determination of the influence of each parameter in the process and the conditions under which the pollutant suffers the highest rates of degradation were selected. In general, results indicate that combination TiO2/H2O2/light irradiation leads to ∼90 % of substrate removal after 30 min of reaction and that hydroxyl free radicals are the main specie responsible for organic matter elimination. Finally, in terms of mineralization and biodegradability, experimental results indicated that part of the organic matter was transformed into CO2 and water and the photo-treatment promoted an increase in samples biodegradability.

Debido al gran incremento de contaminación de suelos y aguas subterráneas ocasionadas por vertidos de combustibles provenientes de lodos de perforación de tipo inversa y recortes, derrames de tuberías o tanques de almacenamiento corroídos, vertederos de desechos aceitosos semisólidos, sitios contaminados por descargas petroquímicas y refinerías, voladura de ductos, actividades fraudulentas, entre otras, se han desarrollado estudios para realizar de forma más eficiente la descontaminación. La biorremediación es una de las tecnologías más aplicada para la descontaminación de suelos impactados con hidrocarburos. Actualmente la preocupación son los efectos que tienen los aditivos y los biocombustibles en la gasolina y el diesel respectivamente, ya que éstos pueden minimizar las emisiones vehiculares a la atmósfera, pueden ayudar a que la contaminación se presente de forma más rápida debido al aumento de co–solvencia de los hidrocarburos en aguas subterráneas, mayor dinámica en suelos y además las inhibiciones hacen que se presente disminución en la degradación de la gasolina y el diesel. El aumento de la pluma de contaminación en un menor tiempo debido a estos compuestos y sus efectos en la biodegradación de gasolina y diesel es el objetivo de la investigación. Con este estudio se quiere obtener el comportamiento dinámico y la biodegradación de algunos de los principales contaminantes del suelo. Se realizaron dos pruebas: 1) Un suelo con una mezcla gasolina–etanol y se observó el efecto que tiene este aditivo sobre el transporte y degradación de la gasolina en el suelo (40 000 ppm de concentración inicial). 2) Un suelo con una mezcla diesel–biodiesel, y de forma similar se observará el efecto del biodiesel sobre el transporte y la degradación del diesel (40 000 ppm de concentración inicial). Las mezclas se compraron en una estación de venta de combustibles. Las dos pruebas se realizaron simultáneamente. Se pudo obtener información sobre el contaminante, en cuánto tiempo podría llegar a un acuífero, y si es necesario remediarlo de forma inmediata. Una contaminación antigua disminuye la velocidad de degradación por microorganismos debido a reacciones de oxidación química que incorporan el contaminante dentro de la materia orgánica, difusión lenta dentro de los poros pequeños y adsorción en las paredes de los mismos, y también la formación de películas sumergidas alrededor de los líquidos en fase no acuosa con una alta resistencia a la transferencia de masa en acuíferos y reactores tipo suspensión.AbstractDue to the great increase in soil and ground water contamination as a result of dumping fuels from inverse drilling mud and cuttings, spills from pipelines or corroded storage tanks, semisolid oil waste dumps, sites contaminated by petrochemical discharge and refineries, pipes bursting, fraudulent activities, and other occurrences, studies have been developed to more efficiently perform decontamination. Bioremediation is one of the most widely applied technologies for decontaminating soil affected by hydrocarbons. The current concern is the effects the additives and biofuels will have on gasoline and diesel, respectively, since they can minimize vehicular emissions in the atmosphere and help contamination to be evidenced more quickly due to the increase in co-solvency of hydrocarbons in ground water and a greater dynamic in the soil. In addition, the inhibitions cause a decrease in the degradation of gasoline and diesel. The object of this study is the increase in the contamination plume in a shorter period of time due to these compounds and their effects on gasoline and diesel biodegradation. This study aims to obtain the dynamic behavior and biodegradation of some main soil contaminants. Two tests were performed: 1) Soil with a mix of gasoline - ethanol. The effect this additive has on the transportation and degradation of gasoline in the soil (40,000 ppm initial concentration) was observed. 2) Soil with a mixture of diesel - biodiesel. Similarly, the effect of biodiesel on the transportation and degradation of diesel (40,000 ppm initial concentration) was observed. The mixtures were purchased in a gas station. The two tests were performed simultaneously. The study obtained information about the contaminant regarding how long it would take to reach an aquifer and whether it is necessary to remedy the situation immediately. An old contamination decreases the speed of degradation by microorganisms due to chemical oxidation reactions that incorporate the contaminant into the organic matter, slow diffusion within the small pores and adsorption in the walls of pores, and the formation of submerged films around the liquids in non-aqueous phase with a high resistance to mass transfer in aquifers and suspension reactors.ResumoDevido ao grande aumento da poluição do solo e das águas subterrâneas ocasionadas por derrames de combustível provenientes de lamas de perfuração de tipo invertidos e corte, vazamentos de oleodutos ou tanques de armazenamento corroídos, descargas de detritos oleosos semi-sólidos, locais contaminados por descargas petroquímicas e refinarias, explosão de oleodutos, atividades fraudulentas, entre outras, têm sido desenvolvidos para realizar estudos de forma mais eficiente a descontaminação. A biorremediação é uma das tecnologias mais aplicadas para a descontaminação de solos impactados com os hidrocarbonetos. Atualmente, a preocupação está nos efeitos que tem os aditivos e os biocombustí- veis na gasolina e no diesel, respectivamente, e como estes podem minimizar as emissões veiculares para a atmosfera, podem ajudar que à poluição se apresente mais rápido devido ao aumento da co-solvência dos hidrocarbonetos nas águas subterrâneas, maior dinâmica em solos também as inibições faz com que se apresente esta diminuição na degradação da gasolina e do diesel. O aumento da pluma da poluição em menos tempo, devido a estes compostos e os seus efeitos sobre a biodegradação de gasolina e diesel é o objetivo da investigação. Com este estudo pretendemos obter o comportamento dinâmico e biodegradação de alguns dos principais contaminantes do solo. Foram realizados dois testes: 1) Um chão uma mistura de gasolina - etanol e foi observado o efeito que tem este aditivo sobre o transporte e degradação da gasolina no chão (Concentração inicial de 40.000 ppm). 2) Um solo com uma mistura diesel - biodiesel, e de forma semelhante será notado o efeito de biodiesel sobre o transporte e degradação de diesel (40.000 ppm) concentração inicial. As misturas foram comparadas em um posto de gasolina. Os dois testes foram realizados simultaneamente. Obtiveram-se Informações sobre o poluente, em quanto tempo poderia chegar a um aquífero, e se necessário remediá-la de forma imediata. Uma velha poluição diminui a velocidade de degradação por micro-organismos devido a reações de oxidação química que incorporam o poluente dentro da matéria orgânica, difusão lenta dentro dos poros pequenos e adsorção nas paredes dos mesmos, e também a formação da película submersa em torno dos líquidos em fase não aquosa com uma elevada resis- tência à transferência de massa em aquíferos e reatores tipo de suspensão. Debido al gran incremento de contaminación de suelos y aguas subterráneas ocasionadas por vertidos de combustibles provenientes de lodos de perforación de tipo inversa y recortes, derrames de tuberías o tanques de almacenamiento corroídos, vertederos de desechos aceitosos semisólidos, sitios contaminados por descargas petroquímicas y refinerías, voladura de ductos, actividades fraudulentas, entre otras, se han desarrollado estudios para realizar de forma más eficiente la descontaminación. La biorremediación es una de las tecnologías más aplicada para la descontaminación de suelos impactados con hidrocarburos. Actualmente la preocupación son los efectos que tienen los aditivos y los biocombustibles en la gasolina y el diesel respectivamente, ya que éstos pueden minimizar las emisiones vehiculares a la atmósfera, pueden ayudar a que la contaminación se presente de forma más rápida debido al aumento de co–solvencia de los hidrocarburos en aguas subterráneas, mayor dinámica en suelos y además las inhibiciones hacen que se presente disminución en la degradación de la gasolina y el diesel. El aumento de la pluma de contaminación en un menor tiempo debido a estos compuestos y sus efectos en la biodegradación de gasolina y diesel es el objetivo de la investigación. Con este estudio se quiere obtener el comportamiento dinámico y la biodegradación de algunos de los principales contaminantes del suelo. Se realizaron dos pruebas: 1) Un suelo con una mezcla gasolina–etanol y se observó el efecto que tiene este aditivo sobre el transporte y degradación de la gasolina en el suelo (40 000 ppm de concentración inicial). 2) Un suelo con una mezcla diesel–biodiesel, y de forma similar se observará el efecto del biodiesel sobre el transporte y la degradación del diesel (40 000 ppm de concentración inicial). Las mezclas se compraron en una estación de venta de combustibles. Las dos pruebas se realizaron simultáneamente. Se pudo obtener información sobre el contaminante, en cuánto tiempo podría llegar a un acuífero, y si es necesario remediarlo de forma inmediata. Una contaminación antigua disminuye la velocidad de degradación por microorganismos debido a reacciones de oxidación química que incorporan el contaminante dentro de la materia orgánica, difusión lenta dentro de los poros pequeños y adsorción en las paredes de los mismos, y también la formación de películas sumergidas alrededor de los líquidos en fase no acuosa con una alta resistencia a la transferencia de masa en acuíferos y reactores tipo suspensión.AbstractDue to the great increase in soil and ground water contamination as a result of dumping fuels from inverse drilling mud and cuttings, spills from pipelines or corroded storage tanks, semisolid oil waste dumps, sites contaminated by petrochemical discharge and refineries, pipes bursting, fraudulent activities, and other occurrences, studies have been developed to more efficiently perform decontamination. Bioremediation is one of the most widely applied technologies for decontaminating soil affected by hydrocarbons. The current concern is the effects the additives and biofuels will have on gasoline and diesel, respectively, since they can minimize vehicular emissions in the atmosphere and help contamination to be evidenced more quickly due to the increase in co-solvency of hydrocarbons in ground water and a greater dynamic in the soil. In addition, the inhibitions cause a decrease in the degradation of gasoline and diesel. The object of this study is the increase in the contamination plume in a shorter period of time due to these compounds and their effects on gasoline and diesel biodegradation. This study aims to obtain the dynamic behavior and biodegradation of some main soil contaminants. Two tests were performed: 1) Soil with a mix of gasoline - ethanol. The effect this additive has on the transportation and degradation of gasoline in the soil (40,000 ppm initial concentration) was observed. 2) Soil with a mixture of diesel - biodiesel. Similarly, the effect of biodiesel on the transportation and degradation of diesel (40,000 ppm initial concentration) was observed. The mixtures were purchased in a gas station. The two tests were performed simultaneously. The study obtained information about the contaminant regarding how long it would take to reach an aquifer and whether it is necessary to remedy the situation immediately. An old contamination decreases the speed of degradation by microorganisms due to chemical oxidation reactions that incorporate the contaminant into the organic matter, slow diffusion within the small pores and adsorption in the walls of pores, and the formation of submerged films around the liquids in non-aqueous phase with a high resistance to mass transfer in aquifers and suspension reactors.ResumoDevido ao grande aumento da poluição do solo e das águas subterrâneas ocasionadas por derrames de combustível provenientes de lamas de perfuração de tipo invertidos e corte, vazamentos de oleodutos ou tanques de armazenamento corroídos, descargas de detritos oleosos semi-sólidos, locais contaminados por descargas petroquímicas e refinarias, explosão de oleodutos, atividades fraudulentas, entre outras, têm sido desenvolvidos para realizar estudos de forma mais eficiente a descontaminação. A biorremediação é uma das tecnologias mais aplicadas para a descontaminação de solos impactados com os hidrocarbonetos. Atualmente, a preocupação está nos efeitos que tem os aditivos e os biocombustí- veis na gasolina e no diesel, respectivamente, e como estes podem minimizar as emissões veiculares para a atmosfera, podem ajudar que à poluição se apresente mais rápido devido ao aumento da co-solvência dos hidrocarbonetos nas águas subterrâneas, maior dinâmica em solos também as inibições faz com que se apresente esta diminuição na degradação da gasolina e do diesel. O aumento da pluma da poluição em menos tempo, devido a estes compostos e os seus efeitos sobre a biodegradação de gasolina e diesel é o objetivo da investigação. Com este estudo pretendemos obter o comportamento dinâmico e biodegradação de alguns dos principais contaminantes do solo. Foram realizados dois testes: 1) Um chão uma mistura de gasolina - etanol e foi observado o efeito que tem este aditivo sobre o transporte e degradação da gasolina no chão (Concentração inicial de 40.000 ppm). 2) Um solo com uma mistura diesel - biodiesel, e de forma semelhante será notado o efeito de biodiesel sobre o transporte e degradação de diesel (40.000 ppm) concentração inicial. As misturas foram comparadas em um posto de gasolina. Os dois testes foram realizados simultaneamente. Obtiveram-se Informações sobre o poluente, em quanto tempo poderia chegar a um aquífero, e se necessário remediá-la de forma imediata. Uma velha poluição diminui a velocidade de degradação por micro-organismos devido a reações de oxidação química que incorporam o poluente dentro da matéria orgânica, difusão lenta dentro dos poros pequenos e adsorção nas paredes dos mesmos, e também a formação da película submersa em torno dos líquidos em fase não aquosa com uma elevada resis- tência à transferência de massa em aquíferos e reatores tipo de suspensão.

This paper reports on the effect of different parameters of ultrasonic power, pollutant initial concentration, pH and the presence of co-existing chemical species (oxygen, nitrogen, ozone, and radical scavengers) on the ultrasonic degradation of the endocrine disruptor 1-H-benzotriazole. Increasing the 1-H-benzotriazole initial concentration from 41.97 to 167.88 μM increased the pollutant degradation rate by 40%. Likewise, a high applied ultrasonic power enhanced the extent of 1-H-benzotriazole removal and its initial degradation rate, which was accelerated in the presence of ozone and oxygen, but inhibited by nitrogen. The most favorable pH for the ultrasonic degradation was acidic media, reaching ∼90% pollutant removal in 2 h. The hydroxyl free radical concentration in the reaction medium was proportional to the ultrasound power and the irradiation time. Kinetic models based on a Langmuir-type mechanism were used to predict the pollutant sonochemical degradation. It was concluded that degradation takes place at both the bubble–liquid interfacial region and in the bulk solution, and OH radicals were the main species responsible for the reaction. Hydroxyl free radicals were generated by water pyrolysis and then diffused into the interfacial region and the bulk solution where most of the solute molecules were present.

The objective of this study was to validate (SANCO/12495/2011 and NTC-ISO/IEC 17025) multi-residue multi-class methods using QuEChERS sample preparation and GC–MS for the analysis of regulated pesticides in tomatoes (Solanum lycopersicum), tamarillos (Solanum betaceum) and goldenberries (Physalis peruviana). These Latin American products are representative and widely produced in Antioquia (Colombia). Sample preparation followed the UNE-EN 15662 method (150 mg MgSO4, 25 mg primary secondary amines and 25 mg of octadecylsiloxane for cleanup; graphitized carbon black was added for tomatoes). Extracts were injected using a programmed temperature-vaporizing injector. The residues were validated over a range from 0.02 mg/kg to 0.20 mg/kg, with 24 analytes validated in tomatoes, 33 in tamarillos and 28 in goldenberries. An initial risk assessment was enabled by monitoring 24 samples in the municipalities of El Penol, Marinilla and San Vicente Ferrer. Risks were found for tomatoes, but no significant risks were found for tamarillos or goldenberries.

Colombia is an agricultural country where many pesticides are used. They are overused in most of the cases, leaving residues in water bodies, soils, and crops. Consequently, it is necessary to analyze the pesticide residues from crops that have been fumigated. Colombia is also an active cattle raiser, and producer of meat and milk. The Diagnosis and Control of Pollution Research Group (GDCON), as an active part of the University of Antioquia, has analyzed residues of several toxic substances in water, soil, and foods using state-of-the-art analytical methods. This chapter presents the results of the analysis obtained by programmed temperature vaporizer–gas chromatography–mass spectrometry (PTV–GC–MS) of organic toxic pollutants, using QuEChERS as the sample preparation method. The presence of pesticide residues in milk, blackberries, and processed meat was demonstrated.

RESUMEN: Se evaluó la degradación del insecticida clorpirifos en muestras de suelo durante 21 días, utilizando el hongo Phanerochaete chrysosporium. En los ensayos se obtuvieron porcentajes de degradación, en promedio, para las muestras con hongo, de 96,3, 82,4 y 62,2% cuando se trabajaron, respectivamente, con concentraciones iniciales de clorpirifos de 0,95, 5,3 y 9,4 µg/g. Igualmente, los porcentajes de degradación estuvieron acompañados del aumento en la velocidad de degradación, cuando se partió de la concentración inicial de 0,95 µg/g. ABSTRACT: Degradation of the insecticide chlorpyrifos was investigated in sterilized soil samples supplemented by the white rot basidiomycete Phanerochaete chrysosporium. Degradation rates were measured during 21-day incubation at pesticide concentrations of 0,95, 5,3, and 9,4 µg/g. Phanerochaete chrysosporium showed ability to biodegrade the insecticide in values of 96,3%, 82,4% and 62,2%, respectively, followed by rapid degradation at low initial concentration of chlorpyrifos. COL0040402

Solutions of the organic pollutant model, Crystal Violet (CV), were subjected to ultrasonic, electrochemical treatment and its combination. Ultrasound was tested at two frequencies (20 kHz or 800 kHz) and 80 W in deionized water. After 120 min, 20 kHz conducted to 6% CV degradation, while 50% elimination was observed at 800 kHz. No mineralization of the organic matter was detected in either case. Electrochemistry, using sulfate (0.35 mol L-1) with IrO2 or Boron Doped Diamond (BDD) electrodes at 20 mA cm-2, was also evaluated. After 45 min the IrO2 and the BDD electrodes conducted to 8% and 95% degradation of the initial substrate; while 15% and 43% mineralization, respectively, was removed after 120 min. The impact of anions was as follows: 3 mM bicarbonate enhanced 800 kHz ultrasonic yields, presence of chloride and sulfate benefit electro-oxidation with IrO2 and BDD electrodes respectively. CV oxidation at an electrode surface can be synergistically improved by ultrasound action at 20 kHz and 800 kHz. In the best combination tested (BDD electrode and 800 kHz ultrasonic wave), CV was removed in 45 min, while 80% of the initial organic carbon was eliminate using BDD electrode and 800 kHz ultrasonic wave.