Federal University of Southern and Southeastern Pará

Godman B., Egwuenu A., Haque M., Malande O.O., Schellack N., Kumar S., Saleem Z., Sneddon J., Hoxha I., Islam S., Mwita J., do Nascimento R.C., Dias Godói I.P., Niba L.L., Amu A.A., et. al.

Antimicrobial resistance (AMR) is a high priority across countries as it increases morbidity, mortality and costs. Concerns with AMR have resulted in multiple initiatives internationally, nationally and regionally to enhance appropriate antibiotic utilization across sectors to reduce AMR, with the overuse of antibiotics exacerbated by the COVID-19 pandemic. Effectively tackling AMR is crucial for all countries. Principally a narrative review of ongoing activities across sectors was undertaken to improve antimicrobial use and address issues with vaccines including COVID-19. Point prevalence surveys have been successful in hospitals to identify areas for quality improvement programs, principally centering on antimicrobial stewardship programs. These include reducing prolonged antibiotic use to prevent surgical site infections. Multiple activities centering on education have been successful in reducing inappropriate prescribing and dispensing of antimicrobials in ambulatory care for essentially viral infections such as acute respiratory infections. It is imperative to develop new quality indicators for ambulatory care given current concerns, and instigate programs with clear public health messaging to reduce misinformation, essential for pandemics. Regular access to effective treatments is needed to reduce resistance to treatments for HIV, malaria and tuberculosis. Key stakeholder groups can instigate multiple initiatives to reduce AMR. These need to be followed up.

Uemura Silva V., Nascimento M.F., Resende Oliveira P., Panzera T.H., Rezende M.O., Silva D.A., Borges de Moura Aquino V., Rocco Lahr F.A., Christoforo A.L.

This paper proposes the assessment of particleboards based on the Circular Economy (CE) approach, in which wood wastes and bio-resins are used to produce circular construction materials and compare them with conventional panels made of synthetic polymers and virgin wood particles. The use of discarded wood in particleboards aims to provide circular routes for this solid waste instead of the landfill after use. In addition, two bio-based polyurethane (PU) and urea–formaldehyde (UF) polymers are compared for the production of particleboards. The alternative particleboards are made with raw wood shavings of the species Pinus taeda, Pinus elliotti and Eucalyptus urograndis, without sifting processing. The particleboards are evaluated by the screw pull-out tensile test, three-point bending test, swelling after water immersion and colourimetry. Additional analyses such as surface roughness, thermal conductivity, apparent porosity and scanning electronic microscopy are performed for the characterisation of the panels. The technical viability of particleboards is obtained by mechanical analysis for higher density composites of PU polymers and eucalyptus wood. Finally, a life cycle assessment of particleboards made from recycled wood and bio-resins reveals that all scenarios for the production of particleboards in a CE approach are environmentally benign alternatives, reducing up to 95% of the environmental impacts to human toxicity, abiotic depletion and other impacts compared to the traditional and linear scenario. The best circular scenarios are more sustainable than linear scenarios, especially for the cases of particleboards are made with medium densities involving eucalyptus or pinus wood wastes and PU polymer.

Covre W.P., Ramos S.J., Pereira W.V., Souza E.S., Martins G.C., Teixeira O.M., Amarante C.B., Dias Y.N., Fernandes A.R.

Improper disposal of copper mining wastes can threaten the ecosystem and human health due to the high levels of potentially toxic elements released into the environment. The objective of this study was to determine the properties of Cu mining wastes generated in the eastern Amazon and their potential risks to environment and human health. Samples of forest soil and artisanal/industrial Cu mining wastes were collected and subjected to characterization of properties and pseudo-total concentrations of Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, and Zn, in addition to chemical fractionation of Cu. The pH ranged from near neutrality to alkaline. Pseudo-total concentrations of Cu were high in all wastes, mainly in the artisanal rock waste, with 19,034 mg kg-1, of which 61% is concentrated in the most reactive fractions. Pollution indices indicated that the wastes are highly contaminated by Cu and moderately contaminated by Cr and Ni. However, only the artisanal rock waste is associated with environmental risk. Non-carcinogenic and carcinogenic human health risks were detected, especially from exposure to Cr in the artisanal rock waste. Prevention actions and monitoring of the artisanal mining area are necessary to avoid impacts to the local population.

Souza Neto H.F., Pereira W.V., Dias Y.N., Souza E.S., Teixeira R.A., Lima M.W., Ramos S.J., Amarante C.B., Fernandes A.R.

Knowledge of arsenic (As) levels in gold (Au) mining areas in the Amazon is critical for determining environmental risks and the health of the local population, mainly because this region has the largest mineral potential in Brazil and one of the largest in the world. The objective of this study was to assess the environmental and human health risks of As in tailings from Au exploration in the eastern Amazon. Samples were collected from soils and tailings from different exploration forms from 25 points, and the total concentration, pollution indexes and human health risk were determined. Concentrations of As were very high in all exploration areas, especially in tailings, whose maximum value reached 10,000 mg kg-1, far above the investigation value established by the Brazilian National Council of the Environment, characterizing a polluted area with high environmental risk. Exposure based on the daily intake of As demonstrated a high health risk for children and adults, whose non-carcinogenic risk indexes of 17.8, extremely above the acceptable limit (1.0) established by the United States Environmental Protection Agency. High levels of As in reactive fractions in underground, cyanidation, and colluvium mining areas, as well as extremely high gastric and intestinal bioaccessibility were found, suggesting that high levels may be absorbed by the local population. The results show that the study area is highly polluted through Au mining activities, putting the environment and population health at risk, and that there is an urgent need for intervention by the environmental control agencies for remediation.

Marassi R.J., Queiroz L.G., Silva D.C., Silva F.T., Silva G.C., Paiva T.C.

This study describes the development of an up-flow tubular air-cathode microbial fuel cell (MFC) bioreactor inoculated with a consortium of Shewanella oneidensis and Clostridium butyricum , fed with dairy wastewater (DW). Due to the high organic load of dairy wastewater, the MFC was operated using different strategies for the start-up (30 days) and the subsequent treatment phases (phase 1: 75 days; phase 2: 30 days). The removals of total chemical and biochemical oxygen demand (TCOD and TBOD) were 94 and 96%, under external resistance of 1.0 kΩ (phase 1), and 96 and 97%, under external resistance of 0.3 kΩ (phase 2). In addition, the MFC treatment provided high efficiency for the removal of organic nitrogen (47%), phosphorus (95%), nitrate (100%), and sulfate (75%). The MFC bioreactor delivered maximum power density of 3.5 W m −3 and current density of 1.1 A m −3 at the end of phase 1, and 2.4 W m −3 and 2.4 A m −3 in phase 2, but achieved modest Coulombic efficiency of 2.1% (phase 1) and 4.4% (phase 2), probably due to other metabolic pathways, besides the electrogenic one. Evaluation of the toxicity of the treated DW at two different trophic levels revealed no acute toxic effects towards Daphnia similis (immobilization less than 20%), but statistically significant chronic toxic effects towards Raphidocelis subcapitata (60% inhibition, using a concentrated sample). The findings indicated that the MFC constructed here had excellent potential for dairy wastewater treatment and energy recovery, and that toxicity assessment should be integrated with the MFC process. • First use of toxicity tests with a microbial fuel cell treating dairy wastewater. • Up-flow microbial fuel cell fed by dairy wastewater delivered 3.5 W m −3 . • The system was stable for at least 3 months. • Removal of COD, BOD, nitrate, and phosphorus exceeded 95%.

Martins B.L., Gomes R.L., Messias Y.S., de Lira S.R., Leão I.C., Almeida L.A., Teixeira M.A., das Chagas M.L., Bravo J.P., Belete A.B., De Medeiros J.R.

Silva M.F., Santos A., Santos R., Figueiredo E., Costa J.C.

Teixeira R.A., Pereira W.V., Souza E.S., Ramos S.J., Dias Y.N., Lima M.W., de Souza Neto H.F., Oliveira E.S., Fernandes A.R.

Artisanal gold (Au) mining is the activity with the highest consumption of mercury (Hg) and the main source of environmental contamination by this element, which is a recurring problem in the Amazon. In this study, contamination and risks caused by Hg to the environment and human health were evaluated in different forms of artisanal Au mining in the Brazilian Amazon. For this purpose, 25 samples of soils and tailings were collected in three types of artisanal mine and one native forest. The mineralogical analysis revealed that there is no occurrence of minerals constituted by Hg. However, the concentrations of Hg in underground mining tailings were very high and exceeded the prevention values established by Brazilian environmental legislation, indicating elevated risk to the ecosystem and human health. The enrichment factor indicated that underground mining tailings are enriched by Hg, submitted to cyanidation or not, suggesting anthropogenic source for the high concentrations of Hg. The geoaccumulation index and the contamination factor showed that the colluvial mining tailings are moderately contaminated, and the tailings from underground mining are highly to extremely contaminated, leading to very high risks to the environment and the health of children from the region. These results represent a great contribution to the Amazon, since they provide subsidies for the definition of policies to mitigate environmental contamination and associated risks. • Underground mining tailings have higher Hg concentrations. • Levels of Hg are up to four times higher than the prevention value. • Pollution indexes indicated that Hg is predominantly from anthropogenic input. • Highly strong environmental risks were found associated with Hg contamination. • The health of children is at risk due to Hg contamination.

Pereira W.V., Teixeira R.A., Souza E.S., Moraes A.L., Campos W.E., Amarante C.B., Martins G.C., Fernandes A.R.

Artisanal mining may have modified the mobility, bioavailability and bioaccessibility of potentially toxic elements (PTEs) in the Serra Pelada gold mine, eastern Amazon, Brazil, which has not yet been studied. The objectives were to perform chemical fractionation of barium (Ba), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn), and to determine the bioaccessibility of these elements in soils and mining wastes collected in agriculture, forest, mining, and urban areas from the influence zone of the Serra Pelada gold mine. Pseudo total concentrations were obtained by acid digestion, chemical fractionation was performed using the Bureau Community of Reference (BCR) sequential extraction, oral bioaccessibility was obtained by the Simple Bioaccessibility Extraction Test (SBET) and lung bioaccessibility was obtained through Gamble's solution. The pseudo total concentrations indicated contamination by Ba, Cu and Ni. The sequential extraction revealed the predominance of all elements in the residual fraction. However, Ba is in high concentrations in the greater mobility forms, ranging from 166.36 to 1379.58 mg kg-1. Regardless of the area, Cr and Cu are more oral bioaccessible in the intestinal phase, and Zn in the gastric phase. Ba, Cr and Zn are not lung bioaccessible, while Cu, Ni and Pb are bioaccessible via inhalation. The PTEs studied deserve attention not only due to the high pseudo total concentrations found (which indicate potential risk), but also the concentrations in high mobility forms and bioaccessible fractions, especially in the areas of greatest anthropogenic occupation.

Gester R., Torres A., Bistafa C., Araújo R.S., da Silva T.A., Manzoni V.

The development of new materials with higher nonlinear optical (NLO) activity is an important goal in photonics and optoelectronics. In this context, a theoretical and systematic investigation on the NLO constants of a set of recently synthesized trans-azo-azomethine dyes is performed using the Density Functional Theory. The results suggest how to enhance the electrical properties through an organized substitution of CN and NO2 chemical groups at specific molecular sites. The analyses of NLO parameters, frontier molecular orbitals, energy gap and chemical hardness indicates that the studied compounds should have promising uses as organic light-emitting diodes.