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The arrival of pelagic sargassum in Cuba is not a phenomenon of great magnitude as in other Caribbean regions, however, there is no adequate management of this biomass. The use of macroalgae in agriculture is a common practice. The objective of this research was to characterize sargassum collected from the Havana coast in December 2021 and March 2023 to detect variations in its chemical composition and to evaluate its potential for developing agricultural inputs. The collected samples were characterized by phytochemical screening, physico-chemical properties, and the content of heavy metals and natural polymers. In both collections, the presence of alkaloids, reducing sugars, amino compounds and steroids was noted; the physicochemical characteristics and biopolymer content varied between collections; and the concentration of metals was below the permissible limit. The results make sargassum a potential raw material for the production of agricultural bioinputs (biofertilizers, biostimulants or biomaterial). [ABSTRACT FROM AUTHOR]

Produced water (PW) from the Cuban oil industry is a source of oil and chemicals into the sea. This kind of wastewater is a complex mixture of organic and inorganic compounds. The high salinity, metals and sediment could pose severe environmental impacts upon inadequate disposal. This study is based on the treatment proposal of this kind of wastewater used nature zeolite (N-Z) taking into account the deposits of this material across the island. Results suggest that, significant changes between a doses in terms of the adsorption of organic compounds were not found evaluated by UV-Vis at 295nm, the behavior was for the basic pH of the solution and the textural characteristics of the N-Z such as low surface area of 35 m2/g. Differents doses of N-Z vs. CL were studied, the best to carry out the adsorption process was 0,5 g of zeolite per 50mL of clear liquid (CL)according to the evaluation of the solid phase by ICP-OES(Inductively coupled plasma - optical emission spectrometry) the higher doses increase the compounds that are part of the zeolite structure. On the other hand the evaluation of the liquid phase with the Spectrophotometer at 295nm were no observed significant changes, demonstrating the non-adsorption of organic compounds. At the best doses the selectivity of the zeolite of heavy metal was Zn2+> Fe2+> Cu2+> Mn2+ and the ion exchange occurring by Al2O3 and CaO, also was evaluated by TGA (Thermogravimetry) analysis detecting a small difference in ash content between the virgin and exhausted zeolite that confirm the adsorption of inorganic compounds. [ABSTRACT FROM AUTHOR]

In the present research, was to determine the remediation coefficients of cadmium and lead of American Romerillo in soils contaminated. The analysis of heavy metals in two soils, the brown soil with carbonate and the dark plastic gleyseous, and in the different organs of the plant, was carried out by atomic absorption spectroscopy. The experiments were conducted at the laboratory level using experimental phytoremediation systems, with more controlled conditions and at the contaminated site, where only the brown soil was analyzed. The biological phytoremediation coefficients obtained, both for the experimental systems and in the in-situ experiments, were greater than one, except for the root biological uptake coefficient for lead. This result is in correspondence with the higher lead concentrations obtained in the leaves with respect to the root, showing the plant's capacity to assimilate this metal. The remediation coefficients obtained show that the American Romerillo has the capacity to bioaccumulate cadmium and lead in both soils. [ABSTRACT FROM AUTHOR]

The objective of this paper was characterize of the chemical point of view, the soils at the emplacement of hazardous waste depository, at Juraguá, Cuba, as part of the Environmental Baseline. It was possible to establish the reference levels of the following heavy metals (MP): copper (Cu), zinc (Zn); chromium (Cr); nickel (Ni); lead (Pb); cadmium (Cd) and manganese (Mn), by the method of Direct Aspiration by Atomic Absorption Spectroscopy (AAS) in air - acetylene flame, according to procedures. Mercury (Hg) was determined using a direct mercury analyzer (DMA - 80), according to the standard procedure. The confidence intervals for the mean with a probability of 95%, were established and are of great importance for the evaluation of the environmental impact of the installation in the soil. These results are within the range reported as natural values and should be considered as references values for the study area. [ABSTRACT FROM AUTHOR]

In this work we investigated the ability of natural zeolite to reduce the content of heavy metals in Cuban light crude oil in order to apply it to water emulsified with crude oil. A granulometric analysis of the zeolite was performed, the highest percentage of the sample was retained in sieves with particle sizes of 3,35 and 1 mm; with which all experiments were performed. According to its chemical characterization, using ICP-AES, a Si/Al molar ratio of 5,43 typical of zeolites with a high silica content, high thermal stability, hydrophobic and stable against acidic solutions was obtained, which confer it practical application. The minor elements detected were Ba, Zn, V and Mo. Adsorption experiments applying natural zeolite with crude oil showed the ability of the material to adsorb heavy metals such as Pb and Hg that were not in their natural structure, in the case of Cr, the lower granulometry favored an adequate transfer surface for the adsorption of this compound, Ca2+ was another ion retained in the zeolite, which is favorable in eliminating the hardness of water contaminated with crude. [ABSTRACT FROM AUTHOR]

The use of rhamnolipids constitutes an attractive and eco-compatible alternative in the remediation of contaminated environments with heavy metals. In the present work, the ability of rhamnolipid produced by P. aeruginosa ORA9 to remove copper in contaminated waters of the Blue Lagoon of El Cobre, was evaluated, to control and reduce the human and environmental risk that these waters represent. The influence of the pH of the rhamnolipid solution (4-10), the contact time (2-10 hours) and the concentration of the biosurfactant (40-120 mg L-1) in the process were studied, through a factorial design Box-Bhenken. An increase in the percentage of copper removal proportional to the contact time and the concentration of the biosurfactant was observed, reaching 48 % removal at 10 h and 120 mg L-1. The results obtained indicate that rhamnolipids can be used in the design of a technology to remove copper in polluted contaminated waters. [ABSTRACT FROM AUTHOR]

Heavy metals contents can be reduced from wastewater using microorganisms through different mechanisms included under the general denomination of bioadsorption. Bioadsorption of heavy metals consists in a passive, fast and reversible catchment of the metal ions present in an aqueous solution by physic and chemical interactions on aviable or non-aviable biological materials. In the present paper, a mixed culture of microorganisms from an activated sludge process was used to reduce four different heavy metals contents from a synthetic solution. Copper, nickel, zinc and lead were prepared at a range of 5 - 30 mg/L. The bioadsorption intensity was determined at two values of mean cell retention time (sludge age). The results demonstrated that Freundlich's isotherm adjusted well (R²> 0,95), with a relatively strong bioadsorption due to intensity parameter "n". Copper, nickel, zinc and lead final contents were 74,60-77, 68%; 75,40-40,26%; 74,54-78, 38% and 25,0-31,6% for 5 and 10 days of sludge age respectively with non-significant differences. [ABSTRACT FROM AUTHOR]

In this work, the most influential factors on the adsorption capacity of the dry biomass of Kluyveromyces marxianus CCEBI 2011 were determined on the removal efficiency of copper (II), zinc (II), and manganese (II) present in the waters of Laguna Azul del Cobre in Santiago de Cuba. Adsorption experiments used 0, 25 gL-1 of biomass, 3 pH levels (4, 4, 5,0 and 6, 2), as well as 3 levels of copper (II), zinc metal concentrations (II) and manganese (II) and five contact times (15, 30, 45, 60 and 90 min). The concentrations of the metals were determined by ICP in the "Elio Trincado" Laboratory of the Geominera Oriente Company. Of the 3 pH levels studied, the one with the best performance was of 6, 2. The tests at the studied concentrations showed significant differences in the percentages of removal, showed a better behavior at lower concentrations, obtaining for copper (II), zinc (II), and manganese (II) removal rates of 74,0 %; 98,8 % and 55 % in concentrations of 25, 2 and 10 mg.L-1, respectively. The dry biomass of Kluyveromyces marxianus CCEBI 2011 was able to remove by 52, 23 and 14 % copper (II), zinc (II) and manganese (II) respectively, present in waters of the Laguna Azul del Cobre, removal values lower than those achieved with synthetic solutions. The results show the influence of pH in the adsorption process. [ABSTRACT FROM AUTHOR]

Kinetic parameters for the adsorption of nickel were studied in the waste CalcinationPlant Company Ernesto Che Guevara biomass Phyllanthus orbicularis synthetic and industrial waste Calcination Plant enterprise solutions. The results showed that the major factors influencing the adsorption capacity of the biomass increases with increasing pH and the initial concentration of nickel in the effluent and is reduced by increasing the biomass concentration. Meanwhile, the removal efficiency of residual nickel increases with increasing pH and concentration of biomass and reduced when the initial concentration of nickel in the effluent increases. The adsorption capacity nickel biomass Phyllanthus orbicularis from synthetic solutions and industrial waste Calcination Plant Company Nickel "Comandante Ernesto Che Guevara" was 44,05 and 26,25 mg/g respectively. The adsorption process nickel biomass Phyllanthus orbicularis follows kinetics pseudosecond order and according to the values Of free energy of adsorption obtained through model-RadushkevichDubinin was 267,26 kJ/mol, this nature demonstrates that corresponds to a process mediated by chemical adsorption where the formation of stable bonds between the functional groups present in the biomass and the metal ions predominates. [ABSTRACT FROM AUTHOR]

In this paper an approach to the theoretical basics associated with environmental management in agroecosystems with probable health risks due to pollution with heavy metals is made. Adverse effects caused by heavy metals to human health have been known for a long time, however, prevent human exposure to heavy metals is not an easy mission especially in undeveloped countries. Mismanagement of agriculture from the environmental point of view, implementation of inappropriate agricultural practices without taking into account soil characteristics or the application of excessive amounts of mineral fertilizers to soils are elements of health risks.The development of agricultural management models linked with a more environmentally and socially sensitive approach to consider human health, as an essential element in social development, are issues of high priority for current society. [ABSTRACT FROM AUTHOR]

The biosorption is considered an alternative technology for removal of heavy metals from wastewater and the use of seaweeds as adsorbents encourages scientific interest, considering the variety, abundance and availability of different species growing or arriving at the coastal shoreline. The aim of the research was to characterize a seaweed biosorbent prepared from marine algae Sargassum, to know their potentialities for heavy metals removal from aqueous solutions. A characterization physico-chemical, morphological and structural of a seaweed bioadsorbent was performed using microanalysis and surface anaytical advanced techiques. Was confirmed of major functional groups present in the alginic acid, alginates, polysaccharides and proteins containing this type of seaweed biomass, biopolymers that facilitate the biosorption mechanisms and consequently they can contribute a high capacity of biosorption of heavy metals of this biosorbente. [ABSTRACT FROM AUTHOR]

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The biosorption is considered an alternative technology for removal of heavy metals from wastewater and the use of seaweeds as adsorbents encourages scientific interest, considering the variety, abundance and availability of different species growing or arriving at the coastal shoreline. The aim of the research was to characterize a seaweed biosorbent prepared from marine algae Sargassum, to know their potentialities for heavy metals removal from aqueous solutions. A characterization physico-chemical, morphological and structural of a seaweed bioadsorbent was performed using microanalysis and surface anaytical advanced techiques. Was confirmed of major functional groups present in the alginic acid, alginates, polysaccharides and proteins containing this type of seaweed biomass, biopolymers that facilitate the biosorption mechanisms and consequently they can contribute a high capacity of biosorption of heavy metals of this biosorbente. [ABSTRACT FROM AUTHOR]

The contamination of wastewater with heavy metals is a big problem for the environment at present. The extensive use of nickel for manufacturing products required by actual society has led to contamination of air, soil and water. One of the objectives of this study is to evaluate the discharge of nickel, presenting the cuantitative information of industrial emissions of this metal in Spain, collected by a important data base, the European Pollutant Release and Transfer Registrer (E-PRTR). The following tests were performed for the removal of nickel by biosorption, selecting as biosorbent the pine cone shell, which has some advantages, as the use of an agricultural waste very abundant in Andalucía low or no cost. The last aim of this work is the study of variables that take part in the biosorption (particle size, pH, etc.) and how they have an influence in the process. [ABSTRACT FROM AUTHOR]

Some industrial effluents have high concentrations of heavy metals like lead, which have high toxicity at low concentrations and its capacity of been absorbed and accumulated in living organisms. In this work was valuated the potential biosorption of Pb(II), in aqueous solution, performing the influence of three pH values, using dry biomass of Bacillus subtilis CCEBI 1032, Pseudomonas aeruginosa CCEBI 1044 and Kluyveromyces marxianus CCEBI 2011. The best results of lead removal was at 60 min, and pH 4,2; 5,2 y 6,2 for Bacillus subtilis CCEBI 1032, Pseudomonas aeruginosa CCEBI 1044 and Kluyveromyces marxianus CCEBI 2011, respectively. [ABSTRACT FROM AUTHOR]

La contaminación por metales pesados a consecuencia del vertimiento de materias residuales que resultan de la actividad humana es uno de los problemas más importantes y complejos con los que se enfrenta la sociedad actual. La necesidad de reducir y minimizar esta contaminación ha llevado al hombre a estudiar la variación de las características químicas de las aguas. Los metales pesados, debido a su alta carga de toxicidad y los riesgos a la salud humana que estos portan, requieren de una atención prioritaria tanto por la ciencia como por la tecnología. Es por ello que este trabajo tiene como objetivo determinar los niveles de concentración de 9 metales pesados (Ni, Zn, Cu, Sn, Pb, Cr, Pb, Hg, Co) en sedimentos de ocho puntos de los Ríos Tínima y Hatibonico,Cuenca San Pedro,Provincia de Camaguey. Para su estudio se empleó la Espectrometría de Absorción Atómica como técnica principal en la cuantificación de los metales dados. El experimento se realizó durante los meses de marzo y abril del año 2003. Los resultados mostraron que de los 9 metales pesados analizados el Ni, Zn, Cu, Sn, Pb, Cr, sus concentraciones fueron superiores a las establecidas por las normativas internacionales. [ABSTRACT FROM AUTHOR]

The heavy metals can be a polluting source in the hydrocycle, if these they are in high concentrations in the silts due to their non biodegradable character and in dependence of the characteristics of the silts. In this work a study of the composition of the silts of the river Cobre of Santiago de Cuba, being chosen four sampling points in the area of de Mina Grande del Cobre, being determined majority components as: volatile organic and inorganic matter, silica and carbonates, as well as heavy metals (Al, Fe, Mn, Cu, Zn, Pb, Cr and Ni) for the method of Spectroscopy of Plasm Inductively Coupled Atomic Emission (ICP-AES) and Spectroscopic of atomic absorption. It was also carried out the study of the sedimentation and of the grain size distribution. [ABSTRACT FROM AUTHOR]

An analytical procedure for the direct determination of Cu, Fe, Zn by flame Atomic Absorption Spectrometry (AAS) and for, Co, Ni, Pb, Cd, Si, Al, B, Fe, Zn, Cu, Cr, Bi, Ba by Inductively Coupled Plasma Emision Spectrometry (ICP-AES) in corvina's muscle from Cienfuegos bay was established. The sample digestion procedure was modified changing the usually employed mixture HNO3-HClO4 by a mixture of HNO3-H2O2 which results less time consuming and move efficient. The evaluation of the accuracy was performed analyzing a certified reference material of dogfish tissue from the Canadian National Research Council (CNRC) and by standard addition. Recoveries between 90-105 % were found in all cases. The relative standard deviation was used as a measure of the precission and values between 0,5-2,5 % for atomic absorption spectrometry and between 5-45 % for Inductively coupled plasma emission spectrometry were found. [ABSTRACT FROM AUTHOR]