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1.
Chemosphere ; 349: 140834, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042421

RESUMO

Beauty salons (BS) are places that deal with a wide range of cosmetics with potentially hazardous chemicals, and their effluent should be properly treated before going to the sewage system, once it represents characteristics of industrial wastewater. This work provides an extensive characterization of a BS effluent and its respective electrochemical treatment by comparing NaCl, Na2SO4, and Na2S2O8 as supporting electrolytes with a boron-doped diamond (BDD) as anode, applying 10 or 30 mA cm-2 of current density (j). The inclusion of UVC irradiation was also performed but the improvements achieved in removing the organic matter were null or lower. The analysis of chemical oxygen demand (COD) removal, energy consumption, and total current efficiency (TCE) was required to prove the efficacy of the processes and the comparative study of the performance of different technologies. Precipitate analysis was also done due to the high turbidity of the raw effluent and the appearance of a precipitate before and during the electrolysis, mainly with Na2S2O8. The precipitate confirmed the presence of silicates and small amounts of heavy metals. The results clearly showed that 6 h of treatment with Na2SO4 achieved 58% of COD removal with an energy consumption of about 0.52 kWh m-3, being the best electrolyte option for treating BS effluent by applying 10 mA cm-2. Under these experimental conditions, the final wastewater can be directly discharged into the sewage system with a lower amount of visible precipitate, and with 73% less turbidity. The treatment here proposed can be used as an alternative to decision-makers and governments once it can be a step further in the implementation of better and advanced politics of water sanitation.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Oxirredução , Esgotos , Sulfatos/análise , Poluentes Químicos da Água/análise , Eletrólitos , Diamante/química , Eletrodos
2.
Environ Sci Technol ; 57(13): 5149-5159, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36939598

RESUMO

We measured submicron aerosols (PM1) at a beachfront site in Texas in Spring 2021 to characterize the "background" aerosol chemical composition advecting into Texas and the factors controlling this composition. Observations show that marine "background" aerosols from the Gulf of Mexico were highly processed and acidic; sulfate was the most abundant component (on average 57% of total PM1 mass), followed by organic material (26%). These chemical characteristics are similar to those observed at other marine locations globally. However, Gulf "background" aerosols were much more polluted; the average non-refractory (NR-) PM1 mass concentration was 3-70 times higher than that observed in other clean marine atmospheres. Anthropogenic shipping emissions over the Gulf of Mexico explain 78.3% of the total measured "background" sulfate in the Gulf air. We frequently observed haze pollution in the air mass from the Gulf, with significantly elevated concentrations of sulfate, organosulfates, and secondary organic aerosol associated with sulfuric acid. Analysis suggests that aqueous oxidation of shipping emissions over the Gulf of Mexico by peroxides in the particles might potentially be an important pathway for the rapid production of acidic sulfate and organosulfates during the haze episodes under acidic conditions.


Assuntos
Poluentes Atmosféricos , Sulfatos , Sulfatos/análise , Poluentes Atmosféricos/análise , Golfo do México , Oxirredução , Óxidos de Enxofre/análise , Aerossóis/análise , Material Particulado/análise , Monitoramento Ambiental , China
3.
Environ Sci Pollut Res Int ; 29(42): 63655-63673, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35460478

RESUMO

Agricultural and livestock activities strongly influence groundwater quality and conditioning its use as water supply in rural areas. The aim was to determine the quality and suitability of the groundwater supply used in dairy farms of an agricultural area of Pampa plain of Córdoba (Argentina). Piper's diagram showed that the groundwater types were sodium bicarbonate, sodium bicarbonate-chloride, sodium chloride-sulfate, and sodium sulfate. Physicochemical parameters revealed that cations and anions showed a high and significant correlation in water samples, indicating a strong water-rock interaction. Nitrate (NO3-) content was significantly correlated with pH, water well depth, and distance from contamination sources. A high positive correlation between arsenic (As) and bicarbonate, sulfate, sodium, and chloride (p < 0.05) indicates a similar origin. Among the pesticides monitored, 2,4-D was detected in 25% of groundwater samples (0.4 to 0.8 µg/L) coinciding with the ordinary application practices. In general, most of the groundwater samples did not comply with national and international regulations for drinking water and dairy hygiene, due to the high content of As, NO3-, bacteria, and the presence of 2,4-D herbicide. However, the quality of water was suitable for livestock drink. The data obtained in this study contribute to a better understanding of the contamination processes taking place and improve the agricultural and livestock management for an efficient use of this resource by dairy farmers.


Assuntos
Arsênio , Água Potável , Água Subterrânea , Herbicidas , Praguicidas , Poluentes Químicos da Água , Ácido 2,4-Diclorofenoxiacético , Bicarbonatos , Cloretos/análise , Água Potável/química , Monitoramento Ambiental , Fazendas , Água Subterrânea/química , Nitratos/análise , Sódio , Bicarbonato de Sódio , Cloreto de Sódio , Sulfatos/análise , Poluentes Químicos da Água/análise , Qualidade da Água , Abastecimento de Água
4.
Environ Sci Pollut Res Int ; 29(25): 37777-37789, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35067870

RESUMO

In this study, four systems (S1, S2, S3, and S4) were evaluated to determine whether basic oxygen furnace sludge (BOFS), mainly composed of Fe (84%, mostly as elemental Fe and FeO), Ca (3%, as CaCO3), and Si (1%), is capable of removing As-spiked, Mn, Mg, and sulfate from an industrial acid mine drainage (AMDi) collected in a gold mine in Minas Gerais, Brazil. In the S1 system (BOFS/deionized water pH 2.5), the stability of the residue was evaluated for 408 h under agitation. The results showed that only Ca and Mg were solubilized, and the pH increased from 2.5 up to 11.4 within the initial 24 h and kept still until the end of the experiment (408 h). The S2 system (BOFS/AMDi) achieved 100% removal of As and Mn, and 70% removal of sulfate after 648 h. In the first 30 min, the pH increased from 2.5 to 10, which was maintained until the end of the experiment. The removal of As, Mn, and sulfate in the presence of hydrogen peroxide (S3 and S4 systems - BOFS/AMDi/H2O2) was similar to that in the S2 system, which contained only BOFS. The formation of iron oxides was not accelerated by H2O2. As regards the removal of arsenic and sulfate species, the formation of incipient calcium arsenate and calcium sulfate dehydrated was indicated by X-ray diffraction analysis and PHREEQC modeling. Dissolved manganese and magnesium precipitated as oxides, according to the geochemical modeling. After contact with AMDi, the raw BOFS, initially classified as hazardous waste, became a non-inert waste, which implies simplified, less costly disposal. Except for sulfate, the concentrations of all the other elements were below the maximum permitted levels.


Assuntos
Arsênio , Poluentes Químicos da Água , Arsênio/análise , Peróxido de Hidrogênio/análise , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Oxigênio/análise , Esgotos , Sulfatos/análise , Óxidos de Enxofre , Poluentes Químicos da Água/análise
5.
Poult Sci ; 99(11): 5647-5652, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33142482

RESUMO

The objective of this study was to evaluate the relative bioavailability (RB) of manganese (Mn) proteinate compared to Mn sulfate for broilers fed a diet based on corn and soybean meal for 20 d. The diets of 1,350 male Cobb broilers were supplemented with 0, 35, 70, 105, or 140 mg of Mn/kg of feed in the form of Mn sulfate or Mn proteinate. Weight gain, feed intake, feed conversion, bone strength, and Mn concentration in the tibia and liver, as well as the concentration of type I collagen in the tibia, were evaluated. No differences were observed for performance variables (P > 0.05) or for type I collage concentration in broiler tibia (P > 0.05), regardless of the source and level of supplementation used. Relative bioavailability was determined using bone strength values and Mn concentration in the tibia and liver, assuming Mn sulfate as the standard source (100%) by the slope-ratio method. The RB of Mn proteinate based on bone strength was 111%, based on liver Mn concentration was 128%, and based on tibia Mn concentration was 105%. Manganese proteinate was more bioavailable than Mn sulfate; it can be an important source of supplementation to improve bone quality in broilers.


Assuntos
Galinhas , Suplementos Nutricionais , Manganês , Ração Animal/análise , Animais , Disponibilidade Biológica , Dieta/veterinária , Fígado/química , Masculino , Manganês/farmacocinética , Compostos de Manganês/análise , Sulfatos/análise , Tíbia/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-32812506

RESUMO

The acid mine drainage (AMD) can causes negative impacts to the environment. Physico-chemical methods to treat AMD can have high operational costs. Through passive biological methods, such as anaerobic reactors, sulfate reduction, and recovery of metals are promoted. This study evaluated the performance of a horizontal anaerobic immobilized biomass (HAIB) reactor for the treatment of synthetic AMD using polyurethane foam as support material, and anaerobic sludge as inoculum. Ethanol was used as an electron donor for sulfate reduction, resulting in an influent chemical oxygen demand (COD) in the range of 500-1,500 mg/L and COD/sulfate ratio at 1. A gradual increase of sulfate and COD concentration was applied that resulted in COD removal efficiencies higher than 78%, and sulfate removal efficiencies of 80%. Higher sulfate and COD concentrations associated with higher hydraulic retention times (36 h) proved to be a better strategy for sulfate removal. The HAIB reactor was able to accommodate an increase in the SLR up to 2.25 g SO42-/L d-1 which achieved the greatest performance on the entire process. Moreover, the reactor proved a suitable alternative for reaching high levels of metal removal (86.95 for Zn, 98.79% for Fe, and 99.59% for Cu).


Assuntos
Reatores Biológicos/microbiologia , Metais Pesados/análise , Mineração , Sulfatos/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Ácidos/química , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Biomassa , Células Imobilizadas/microbiologia , Oxirredução , Esgotos/química , Esgotos/microbiologia , Bactérias Redutoras de Enxofre/crescimento & desenvolvimento
7.
Braz. J. Pharm. Sci. (Online) ; 56: e18586, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1132054

RESUMO

Vanadyl sulfate (VS) is an ingredient in some food supplements and experimental drugs. This study was designed to assay the effects of VS on biomarkers of oxidative stress and inflammation in renal tissue of rats with diabetes type 2. 30 male Wistar rats were divided into three equal groups as follow: non-diabetics, non-treated diabetics and VS-treated diabetics. Diabetes type 2 has been induced through high fat diet and fructose in the animals. Diabetic rats were treated with 25 mg/kgBW of VS in water for 12 weeks. At the end of study, glucose and insulin were measured using commercially available kits in serum and biomarkers of oxidative stress and inflammation in renal homogenates of animals were measured by related methods. Compared to controls, glucose and insulin were increased significantly in non-treated diabetic rats (p-value <0.05) that showed the induction of diabetes type 2 in rats. The results showed that in VS-treated diabetic rats compared to the non-treated diabetic group, vanadyl sulfate significantly reduced the glucose and insulin secretion and changed renal inflammatory and oxidative markers, except protein carbonyl so that we couldn't find any significant changes. Our study showed that vanadyl supplementation had positive effects on oxidative stress and inflammation biomarkers in kidney of diabetic rats


Assuntos
Animais , Masculino , Ratos , Sulfatos/análise , Vanadatos/análise , Biomarcadores/análise , Preparações Farmacêuticas/administração & dosagem , Interleucina-1/antagonistas & inibidores , Interleucina-10/antagonistas & inibidores , Estresse Oxidativo/imunologia , Suplementos Nutricionais/efeitos adversos , Diabetes Mellitus Tipo 2/patologia , Secreção de Insulina , Insulina/farmacologia
8.
J Hazard Mater ; 379: 120695, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31279310

RESUMO

This study focused on investigating reactor performance, simultaneous methanogeneis and denitrifiction (SMD) process for treatment of a sulfate plus organic sulfur - rich 3,4,5-Triethoxybenzaldehyde (TMBA) manufacturing wastewater with variable COD/TSO42- (total sulfate) ratio by micro-electric field- zero-valent-iron (ZVI) UASB for 390 days. The initial COD/TSO42- was set as 1.42, 0.9 and 0.5, respectively by manually introducing sulfate. The experimental results indicated that micro-electric field- zero-valent-iron UASB was an attractive integrated option for satisfactory COD removal, nitrate reduction and a reasonable methane yield rate even at COD/TSO42- as low as 0.9. Further declining the COD/TSO42- to 0.5 can result in a moderate inhibition of SMD process. The behavior of organic S release was not inhibited over the entire experimental period. Thus, surprisingly, sulfate concentration in the effluent was always higher than that in the influent. In comparison with sludge sample at Day-1, sludge at Day-390 was characterized with high abundant Tissierella Soehngenia, Anaerolinaceae and Brevundimonas diminuta, which played critical role in promising performance in COD abatement. The relatively low abundance of sulfate reducing bacteria (SRB) such as Desulfobulbus and Desulfomicrobium can explain the lower sulfate reduction efficiency in term of high concentration of sulfate plus released from organic S-rich compounds.


Assuntos
Reatores Biológicos/microbiologia , Técnicas Eletroquímicas/métodos , Ferro/química , Metano/biossíntese , Sulfatos/análise , Águas Residuárias , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Anaerobiose , Benzaldeídos/química , Análise da Demanda Biológica de Oxigênio , Desnitrificação , Águas Residuárias/química , Águas Residuárias/microbiologia
9.
Environ Sci Pollut Res Int ; 26(16): 16366-16377, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980375

RESUMO

The creation of pit lakes is usually an acceptable solution from the landscaping point of view for voids left by discontinued open-pit mines. However, without rehabilitation, these voids represent a potential environmental risk. The aim of the present work was to assess, for the first time, the water quality, i.e., physicochemical characteristics, metal and metalloid (MM) content, and ecotoxicity of the waters of the El Cobre Blue Lagoon, a pit lake formed in an open-pit copper mine in Cuba. Potential effects of rainy season vs. dry season and spatial location (different depths) on water characteristics were considered. Results revealed that water contained was moderately acidic (pH = 4.6 ± 0.2), with high electrical conductivity (EC = 3.02 ± 0.03 mS cm-1), whatever the season. Dissolved oxygen (DO = 9.9 ± 2.0 mg L-1), total dissolved solid (TDS = 7003 ± 245 mg L-1), and sulfate concentration (6556 ± 1410 mg L-1) in the El Cobre Blue Lagoon water were above acceptable limits for sources of surface water as recommended by Cuban standard (NC 1021:2014). High copper (43.6 ± 1.7 mg L-1) and manganese (24.1 ± 1.1 mg L-1) contents were detected. Except for EC, sulfates, chlorides, TDS, nitrates, and phosphates, other physicochemical parameters were stable between dry and rainy seasons (p < 0.05). El Cobre Blue Lagoon waters showed an ecotoxicological impact on Vibrio fischeri. No significant differences were detected between all sampling points in the lake for each parameter monitored for a given time. These first results show the spatial homogeneity but poor quality of waters from El Cobre Blue Lagoon. Remediation processes need to be implemented in order to lessen the human and environmental health risk and favor potential water reuse. We suggest the use of constructed wetlands for water treatment. This preliminary research work can serve to alert Cuban local public authorities to the need to rehabilitate such sites.


Assuntos
Lagos/análise , Mineração , Qualidade da Água , Aliivibrio fischeri/efeitos dos fármacos , Cobre , Cuba , Ecotoxicologia/métodos , Monitoramento Ambiental/métodos , Humanos , Lagos/química , Metais/análise , Nitratos/análise , Estações do Ano , Sulfatos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
10.
Environ Sci Process Impacts ; 20(11): 1546-1558, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30357193

RESUMO

Organosulfates are formed in the atmosphere from reactions between reactive organic compounds (such as oxidation products of isoprene) and acidic sulfate aerosol. Here we investigated speciated organosulfates in an area typically downwind of the city of Manaus situated in the Amazon forest in Brazil during "GoAmazon2014/5" in both the wet season (February-March) and dry season (August-October). We observe products consistent with the reaction of isoprene photooxidation products and sulfate aerosols, leading to formation of several types of isoprene-derived organosulfates, which contribute 3% up to 42% of total sulfate aerosol measured by aerosol mass spectrometry. During the wet season the average contribution of summed organic sulfate concentrations to total sulfate was 19 ± 10% and similarly during the dry season the contribution was 19 ± 8%. This is the highest fraction of speciated organic sulfate to total sulfate observed at any reported site. Organosulfates appeared to be dominantly formed from isoprene epoxydiols (IEPOX), averaging 104 ± 73 ng m-3 (range 15-328 ng m-3) during the wet season, with much higher abundance 610 ± 400 ng m-3 (range 86-1962 ng m-3) during the dry season. The concentration of isoprene-derived organic sulfate correlated with total inorganic sulfate (R2 = 0.35 and 0.51 during the wet and dry seasons, respectively), implying the significant influence of inorganic sulfate aerosol for the heterogeneous reactive uptake of IEPOX. Organosulfates also contributed to organic matter in aerosols (3.5 ± 1.9% during the wet season and 5.1 ± 2.5% during the dry season). The present study shows that an important fraction of sulfate in aerosols in the Amazon downwind of Manaus consists of multifunctional organic chemicals formed in the atmosphere, and that increased SO2 emissions would substantially increase SOA formation from isoprene.


Assuntos
Aerossóis/química , Atmosfera/química , Compostos Orgânicos/análise , Sulfatos/análise , Aerossóis/análise , Brasil , Butadienos , Cidades , Monitoramento Ambiental , Hemiterpenos , Espectrometria de Massas , Compostos Orgânicos/química , Oxirredução , Sulfatos/química , Vento
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