New low-cost biofilters for SARS-CoV-2 using Hymenachne grumosa as a precursor.

The ongoing global spread of COVID-19 (SARS-CoV-2 2019 disease) is causing an unprecedented repercussion on human health and the economy. Despite the primary mode of transmission being through air droplets and contact, the transmission via wastewater is a critical concern. There is a lack of techniques able to provide complete disinfection, along with the uncertainty related to the behavior of SARS-CoV-2 in the natural environment and risks of contamination. This fact makes urgent the research towards new alternatives for virus removal from water and wastewater. Thus, this research aimed to characterize new lost-cost adsorbents for SARS-CoV-2 using Hymenachne grumosa as a precursor and verify its potential for removing SARS-CoV-2 from the solution. The aquatic macrophyte H. grumosa had in natura and activated carbon produced with H. grumosa and zinc chloride (ZnCl2,1:1) impregnation and carbonization (700 °C, 1 h) were incubated for 24 h with inactivated SARS-CoV-2 viral suspension, and then the ribonucleic acid (RNA) was extracted and viral load quantified through reverse transcription-quantitative polymerase chain reaction (RT-qPCR) technique. The results demonstrated the great adsorption potential, achieving removal of 98.44% by H. grumosa "in natura", and 99.61% by H. grumosa with carbon activation, being similar to commercial activated carbon (99.67%). Thus, this study highlights the possibility of low-cost biofilters to be used for SARS-CoV-2 removal, as an excellent alternative for wastewater treatment or watercourses decontamination.

Composting of fish waste and its phytotoxicity effects.

This work aimed to evaluate the composting of the mixture of residues from fish filleting, using sawdust as a structuring material as an alternative for stabilization, through physical-chemical analysis and phytotoxicity. The experiment was carried out in a composter 1.10 m long, 1.50 m wide, and 1.20 m high and presenting 2.50 m in total height, which received the mixture of fish filleting wastes and sawdust in a5:3 ratio, respectively. The results demonstrated that composting in cells is an efficient alternative for the decomposition of the mixture of fish filleting and sawdust residues. The rapid decomposition of fish waste and the low C/N ratio harms the development of thermophilic microorganisms during the composting of the mixture of fish filleting and sawdust residues. The compaction of the sawdust layers and the absence of stirring in the composting method in cells collaborate for the compost to need a time greater than 60 days to be recommended as simple organic fertilizer. The biomass stirring is necessary so that sawdust can be considered a good structuring agent. The phytotoxicity test should be taken into account by the Normative Instruction n° 25/2009 as an indicator of compost maturity.

Evaluation of Enydra anagallis remediation at a contaminated watercourse in south Brazil.

The aim of this study was to investigate the phytoremediation potential promoted by Enydra anagallis at anthropogenic polluted area - Santa Bárbara Stream, south Brazil. The watercourse was selected considering it is the main source of water to Pelotas city and the presence of high levels of nutrients and toxic metals. The phytoremediation indexes as bioconcentration factor (BCF), translocation factor (TF), and plant effective number (PEN) were estimated. The results highlighted the possibility of application of E. anagallis in phytoextraction of Ca, K, Mg and P, showing the ability of maintaining high levels of elements in aerial parts of the plant. It was also detected the rhizofiltration mechanism (BCF > 1.0 and TF < 1.0), with possible application for the removal of aluminum, arsenic, chromium, copper, iron, manganese, sodium, nickel, lead, sulfur, vanadium and zinc. Regarding the Plant Effective Number (PEN), it can be highlighted the values found for Al (55 plants), P (38 plants) and S (56 plants), being the number of plants needed for removal of 1 g. Thus, E. anagallis showed natural potential for removing contaminants from the aquatic environment and along with further studies, it could be a good recovery alternative for other contaminated watercourses.

Bioprospection of indigenous flora grown in copper mining tailing area for phytoremediation of metals.

The study evaluated plants with phytoremediation potential that occur spontaneously in an area of copper mining tailings in Southern of Brazil. Eleven plant species were investigated for heavy metal concentrations in its biomass. All species showed copper concentrations greater than 100 mg kg-1, and seven species highlighted for copper concentrations between 321 and 586 mg kg-1 and these species showed Cr concentrations between 25 and 440 mg kg-1. The species S. viarum Dunal and B. trimera Less were highlighted showing the highest concentrations of Cr (586 mg kg-1) and Cu (440 mg kg-1), respectively. Seven species showed Pb phytoextraction potential and four species showed Cu phytostabilization potential. It was concluded that the investigated species are adapted to low nutritional conditions and showed tolerance to heavy metals, mainly Cu, Pb and Cr in its biomass.

Phytoremediation of heavy metals and nutrients by the Sagittaria montevidensis into an anthropogenic contaminated site at Southern of Brazil.

The evaluation of plants occurring naturally at contaminated environments are essential for applying this species in remediation techniques. In this context, the Sagittaria montevidensis with potential for phytoremediation was studied at an anthropogenic polluted stream in southern Brazil. The nutrients and heavy metal content were determined in the phytomass. The phytoremediation indexes were evaluated such as bioconcentration factor (BCF), translocation factor (TF), plant effective number (PEN), and potential phytoremoval (mg m-2). The S. montevidensis was then detected as presenting natural phytoextraction ability for potassium and calcium elements and also demonstrated rhizofiltration potential for phosphorus, manganese, aluminum, vanadium, sulfur, iron, arsenic, copper, magnesium, zinc, sodium, lead, cadmium, nickel, chromium, considering its ability of bioaccumulating these contaminants and retain high levels in the roots. The highest potential for bioremoval (mg m-2) of the S. montevidensis was detected for potassium and calcium (recommending thus the use for phytoextraction) and for aluminum, phosphorus, iron, magnesium, sulfur, and sodium, along with heavy metals (recommended for rhizofiltration). The S. montevidensis decontamination ability, along with its biomass production and its adaptability represents a great advance in order to the recovery of this degraded area and possible application in other contaminated watercourses in Brazil.

SARS-CoV-2 removal with a polyurethane foam composite.

The pandemic of COVID-19 (SARS-CoV-2 disease) has been causing unprecedented health and economic impacts, alerting the world to the importance of basic sanitation and existing social inequalities. The risk of the spread and appearance of new diseases highlights the need for the removal of these pathogens through efficient techniques and materials. This study aimed to develop a polyurethane (PU) biofoam filled with dregs waste (leftover from the pulp and paper industry) for removal SARS-CoV-2 from the water. The biofoam was prepared by the free expansion method with the incorporation of 5wt% of dregs as a filler. For the removal assays, the all materials and its isolated phases were incubated for 24 h with an inactivated SARS-CoV-2 viral suspension. Then, the RNA was extracted and the viral load was quantified using the quantitative reverse transcription (RT-qPCR) technique. The biofoam (polyurethane/dregs) reached a great removal percentage of 91.55%, whereas the isolated dregs waste was 99.03%, commercial activated carbon was 99.64%, commercial activated carbon/polyurethane was 99.30%, and neat PU foam reached was 99.96% for this same property and without statistical difference. Those new materials endowed with low cost and high removal efficiency of SARS-CoV-2 as alternatives to conventional adsorbents.

Analysis of Baccharis dracunculifolia and Baccharis trimera for Phytoremediation of Heavy Metals in Copper Mining Tailings Area in Southern Brazil.

This study aimed to investigate the phytoremediation potential promoted by Baccharis dracunculifolia DC. and Baccharis trimera (Less.) DC. in copper mining tailing area, in the Southern part of Brazil. The plants were selected considering their spontaneous growth in tailing area. The phytoremediation indexes including translocation factor (TF), bioconcentration factor (BCF), metal extraction ratio (MER), and plant effective number (PEN) were assessed. Both species showed higher concentrations of heavy metals in the roots than to the shoots. B. trimera has potential for phytoextraction of Zn, Cd, Cr, and Pb and phytostabilization of Ba and Ni, whereas B. dracunculifolia demonstrated potential for phytoextraction of Pb and phytostabilization of Cu, Zn, and Ba. B. trimera showed higher potential in phytoremediation of the metals such as Cu > Zn > Cr > Ni and Cd than the B. dracunculifolia plants. A smaller number B. trimera plants was required to remove 1 g of Cu, Zn, Cr, Pb, Ni, and Cd than B. dracunculifolia plants, and implies that B. trimera is more efficient for decontamination of the metals. Both species showed potential for phytoremediation of metals in the mining tailing area under study.

The analysis of green roof's runoff volumes and its water quality in an experimental study in Porto Alegre, Southern Brazil.

The green roofs are structures characterized by the application of vegetation cover in the buildings, using adequate waterproofing and drainage systems. It allows the reduction of surface runoff and delay in peak flow, contributing to the mitigation of flood events in urban areas. Therefore, this study aimed to evaluate the effect of the use of vegetal coverings on the surface runoff, taking into account quantitative and qualitative aspects, using an experimental module installed in the city of Porto Alegre, Brazil. The experimental station consisted of four modules: two horizontal modules with and without vegetation cover and two modules with slopes of 15° with and without vegetation cover. It was evaluated 19 precipitation events, and it was verified the volumes drained in each module after 3, 6 and 12 h from the beginning of precipitation. The water samples were collected in order to analyse the quality of the runoff from the experimental modules. The results have shown that the use of vegetal coverings can provide better distribution of the surface runoff, as well as a decrease of the speed of excess water release with no surface runoff in the first 3 h after the onset of rainfall in the horizontal module. Additionally, it was proved the reduction in drained volumes, with the flat module with vegetation cover being capable of retaining completely precipitations with volumes of approximately 22 mm. The vegetation cover module in roofs was the one that has presented better results regarding the reduction of the flow, presenting an average retention percentage of 91.7% for the first 3 h, indicating that the slope is an important factor. The physical-chemical analysis of the water shows that for all analysed modules, it is possible to use water for non-potable uses, although the water quality of the modules with vegetation cover is lower when compared to the water coming from the module without vegetation cover.

Potential of Solanum viarum Dunal in use for phytoremediation of heavy metals to mining areas, southern Brazil.

Mining tailing areas may contain metal minerals such as Cu, Pb, Zn, Cr, and Cd at high concentrations and low nutrients for the growth of plants. This kind of conditions of the area, as well as lack of tailing structure, may limit the development of plants on these areas. Thus, the present study determined the metal, macronutrient, and micronutrient concentrations in the tissues of the roots and shoots of the Solanum viarum Dunal species as well as it evaluated the potential use of the plant for phytoremediation of mining tailing areas contaminated with heavy metals. The macronutrients, micronutrients, and heavy metals in the roots and shoots were determined by the digestion method with nitric and perchloric acid (HNO3-HClO4) and quantified by the ICP-OES. In S. viarum, the average concentrations of the metals presented in the dry biomass varied between the shoots and roots, being higher in the roots for metals such as Cu (229 mg kg-1), Zn (232 mg kg-1), Mn (251 mg kg-1), Cr (382 mg kg-1), Ni (178 mg kg-1), Pb (33 mg kg-1), and Ba (1123 mg kg-1). S. viarum indicates the possibility of a potential application in phytoremediation and treatment of areas contaminated with heavy metals.

Compostos voláteis associados ao risco carcinogênico e não carcinogênico / Volatile compounds associated with carcinogenic and non-carcinogenic risk

RESUMO O presente trabalho consiste na avaliação da existência de risco e sua quantificação em casos de vazamentos de derivados do petróleo em uma refinaria localizada na Região Sudeste do Brasil. A área apresenta solo subsuperficial e água subterrânea contaminados por hidrocarbonetos de petróleo e outras substâncias em consequência do funcionamento de uma refinaria. Foram consideradas as vias de exposição por inalação aos contaminantes presentes nesses dois meios. A quantificação do risco de câncer e do quociente de perigo foi realizada para cada substância química, permitindo verificar que, para a exposição a água subterrânea contaminada, não houve efeito carcinogênico e não carcinogênico para os compostos analisados por meio da via de inalação. Já para a exposição a solo subsuperficial contaminado, verificou-se que todos os elementos detectados apresentaram riscos carcinogênicos para ambas as condições analisadas (ambiente aberto e fechado) e ambos os receptores (trabalhadores e comercial). Os elementos benzeno, tolueno, etilbenzeno, o-xileno e m-xileno apresentaram risco não carcinogênico para ambientes fechados em solo subsuperficial contaminado. Em ambientes abertos, somente o xileno,m- não apresentou risco não carcinogênico. Para receptores trabalhadores, somente o benzeno apresentou risco não carcinogênico. Destaca-se a grande importância do gerenciamento de risco para posterior recuperação dessa área afetada.

Abstract The present study was an assessment and risk quantification of derivatives from oil spill at a refinery located in the Southeast of Brazil. The area presents subsurface soil and groundwater contaminated by petroleum hydrocarbons and other substances from the refinery. Inhalation exposure routes have been evaluated due to the presence of contaminants in the affected area. Risk quantification and hazard ratio were performed for each chemical substance, allowing to verify that, for exposure from contaminated groundwater, there was no carcinogenic and non-carcinogenic effect considering the inhalation route. As for exposure to contaminated subsurface soil, all the elements were detected as having the carcinogenic risk for both analyzed conditions (open and closed environments), and both receptors (worker and commercial). The elements Benzene, Toluene, Ethylbenzene, o-Xylene, and m-Xylene, have presented a non-carcinogenic risk for closed environments from contaminated subsurface soil. In open environments, only m-Xylene did not present non-carcinogenic risk. For the workers receptors, only Benzene has presented a non-carcinogenic risk. It might be highlighted the importance of risk management for the subsequent recovery of this affected area.

Produção, caracterização e aplicação de carvão ativado de caroço de pêssego no tratamento de efluente têxtil / Production, characterization, and application of activated charcoal from peach kernel in textile effluent treatment

RESUMO O objetivo deste estudo foi caracterizar a produção de um carvão de caroço de pêssego e também avaliar a adsorção de corantes têxteis pelo carvão ativado de caroço de pêssego. A ativação do carvão foi realizada utilizando cloreto de zinco como agente oxidante. O carvão ativado foi então utilizado na adsorção de corantes, para posterior aplicação no tratamento de um efluente têxtil. Primeiramente, realizou-se a produção de carvão ativado com as temperaturas de 500, 700 e 900°C e tempo de carbonização de 10 15 e 20 minutos e verificou-se a remoção dos corantes preto reativo 5 e azul de metileno. De acordo com a metodologia de superfície de resposta, a melhor temperatura de produção apresentou-se acima de 700°C com tempo de exposição de 10 minutos para os dois corantes. Desse carvão ativado, avaliaram-se os dados de densidade, teor de umidade e cinzas, pH e rendimento. Também foram realizados ensaios cinéticos e de equilíbrio. Os dados foram ajustados a três modelos cinéticos. As medidas para determinação da eficiência na remoção de cor do efluente têxtil foram realizadas pelo método espectrofotométrico e demonstraram média de remoção superior a 62% da cor presente no efluente bruto. Desse modo, o caroço de pêssego demonstrou elevado potencial para a produção de carvão ativado visando o tratamento de efluentes contendo corantes, podendo servir como alternativa de baixo custo.

ABSTRACT The aim of this study was to characterize the production of activated charcoal from the peach kernel and assess the adsorption of textile dyes by this activated charcoal. The activation of the charcoal was performed using zinc chloride as the oxidizing agent. The activated charcoal was then used in the adsorption of dyes for later application in the treatment of a textile effluent. Firstly, the production of activated carbon was carried out at temperatures of 500, 700, and 900°C and carbonization time of 10, 15, and 20 minutes and the removal of the Reactive Black 5 and Methylene Blue dyes was verified. According to the methodology of response surface, the best production temperature was above 700°C with 10 min exposure for both dyes. From this activated carbon, data on density, moisture and ash content, pH, and yield were evaluated. Kinetic and equilibrium tests were also performed. The data were fitted to three kinetic models. The measures to determine the efficiency in the color removal of the textile effluent were carried out by the spectrophotometric method and demonstrated an average removal greater than 62% of the color present in the raw effluent. In this way, the peach kernel demonstrated a high potential for the production of activated carbon aiming at the treatment of effluents containing dyes and can serve as a low cost alternative.

Crescimento e teor de cromo em mamoneira cultivada em solo receptor de resíduos de curtume e carboníferos / Growth and chrome content of castor bean plants cultivated in soil with application of tannery residues and coal mining waste

RESUMO A produção de resíduos tem aumentado em proporção direta com a industrialização dos países. Sendo assim, a disposição adequada desses resíduos é uma questão largamente discutida entre os órgãos ambientais. Por isso, o objetivo deste trabalho foi estudar o efeito residual de adições sucessivas de resíduos de curtume e da mineração de carvão sobre as propriedades químicas do solo e o acúmulo de cromo (Cr) em mamoneira. Os tratamentos aplicados em condições de campo foram: T1 - controle, ou seja, solo sem adubação; T2 - solo adubado com nitrogênio-fósforo-potássio (NPK) + calcário para atingir pH 6,0; T3 - solo misturado com lodo de curtume em dose adequada para se atingir pH 6,0 + PK; T4 - solo receptor de duas vezes a dose de lodo de curtume utilizada no T3 + PK; T5 - solo misturado com resíduo carbonífero + NPK + calcário em quantidade adequada para atingir pH 6,0; T6 - solo misturado com resíduo carbonífero + lodo de curtume em dose adequada para atingir pH 6,0 + PK; T7 - solo misturado com serragem cromada + NPK + calcário em quantidade adequada para atingir pH 6,0; T8 - solo misturado com Cr mineral + lodo de curtume em dose adequada para se atingir pH 6,0 + PK. Em campo, o solo recebeu os diferentes tratamentos. Posteriormente, amostras desse solo foram acondicionadas em vasos e o experimento com as plantas foi conduzido em delineamento inteiramente ao acaso, com três repetições por tratamento. O rendimento de matéria seca mostrou que a aplicação de serragem cromada (T7) proporcionou o maior crescimento da mamoneira, bem como os maiores teores de P no seu tecido. Os teores de Cr na parte aérea das plantas não atingiram níveis que podem ser considerados de contaminação desses vegetais. A distribuição desse elemento nas diferentes partes das plantas de mamoneira demonstrou a possibilidade de utilização futura dos grãos para produção de biodiesel.

ABSTRACT The production of waste has been increasing in direct proportion to the industrialization of the countries. Therefore, the adequate disposal of these wastes is an issue widely discussed among environmental agencies. Thus, the aim of this work was to study the residual effect of successive additions of tannery and coal mining waste on the chemical properties of the soil and the accumulation of chromium in castor bean plants. The treatments applied under field conditions were: T1 - control, that is, soil without fertilization; T2- soil fertilized with nitrogen-phosphorus-potassium (NPK) + limestone to reach pH 6.0; T3 - soil mixed with tannery sludge at a dose adequate to reach pH 6.0 + PK; T4 - soil receptor of twice the dose of tannery sludge used in treatment 3 + PK; T5 - soil mixed with coal residue + NPK + limestone in an amount adequate to reach pH 6.0; T6 - soil mixed with coal residue + tannery slurry at a dose adequate to reach pH 6.0 + PK; T7 - soil mixed with chrome sawdust + NPK + limestone in adequate quantity to reach pH 6.0; T8 - soil mixed with mineral Cr + tannery sludge at a dose adequate to reach pH 6.0 + PK. In the field, the soil received the different treatments. Subsequently, samples of this soil were conditioned in pots and the experiment with the plants was conducted in a completely randomized design, with three replicates per treatment. Subsequently, samples of this soil were placed in pots and the experiment with plants was conducted in a completely randomized design, with three replications per treatment. The dry matter yield showed that the application of chrome sawdust (T7) provided the highest growth of the castor bean, as well as the higher levels of P in its tissue. Chromium content in the aerial part of the plants did not reach levels that can be considered as contamination of these plants. The distribution of chromium in the different parts of the castor bean plants demonstrated the possibility of future use of the grains to produce biodiesel.