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Lead (Pb) is one of the most paradoxical elements, both having diverse practical uses, as well as being extremely toxic to humans, and especially to children. The use of Pb records a steady growth with annual production currently exceeding 10 million metric tons. In spite of the environmental awareness of modern society, humans are still exposed to Pb through its emission by smelting and mining activities, and also by Pb-bearing mine wastes and soils. Here, we review the chemical and mineralogical forms of Pb generated from smelting and mining processes and subsequently altered in tailings, slag piles, and soils. In smelter plumes, Pb is emitted to the atmosphere either in the form of smaller nano-size particulate matter (PM) often associated with S, or larger micrometer Pb-bearing PM matter accompanied by oxide-silicate matrices. Pb-bearing phases in mine tailings and impacted soils depict a greater mineralogical and chemical complexity than those emitted from smelters and the larger particle size of this PM also leads to a lower Pb bioavailability. High resolution observations in aquatic system, soils and rock coatings impacted by smelting and mining activities show the presence of Pb-bearing phosphates, sulfides, sulfates, carbonates, and oxide nanoparticles. Larger micrometer size particles of Pb-bearing minerals form often through the aggregation of Pb-bearing nanoparticles, a process commonly referred to as crystallization through particle attachment. Mobilization of Pb within soil columns is strongly affected by the transport of colloids, especially those composed of organic matter and Fe-hydroxides because Pb is taken up efficiently by these two soil components. The extraordinary variability and complexities of all of these processes suggest that future reduction of Pb contamination in the environment and its impact on human health mainly depends on eliminating or greatly reducing Pb-release from smelting operations and tailings impoundments.

The atmospheric aerosol particles have a potential heavy burden on environment, climate, and human health, which were closely related to the surface physicochemical properties. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) technique is a powerful tool to obtain detailed surface chemical information since it has high surface sensitivity for both elements and molecular ions, and high mass resolution. In this work, size-fractioned aerosol particles in the range of 0.43–10 µm during a severe haze episode in Beijing were analyzed by TOF-SIMS, the variation characteristics of chemical species corresponding to particle size and air pollution level was investigated by the normalization of secondary ion intensities, the possible sources were identified through principal component analysis (PCA), and the influence of meteorological factors and air mass transmission were also investigated. The study results showed that the surface chemical components of PM2.5 were more complicated during haze episode than on clean days. A total of 17 organic and inorganic species were detected, including crustal elements, heavy metals, sulfate, nitrate, siliceous compounds, hydrocarbons, oxygen-containing organics, and nitrogen-containing organics. In general, the particle surface mainly contained crustal elements, hydrocarbons, and carbon-containing inorganics. Organic and secondary ions significantly increased in heavy-polluted days, indicating the aging process of particles. Inorganic compounds had a higher percentage in coarse mode, while organic compounds were higher in accumulation mode. PCA results indicated that urban aerosol during this haze episode mainly came from vehicle emissions (24.7%), coal-fired combustion (22.4%), organic aerosol (19.3%), and dust resuspension (19.6%). The northern air mass could facilitate the dilution of air pollutants with the surface secondary formed components of particles significantly decreased.

Activated carbon prepared from grape branches was used as a remarkable adsorbent to uptake naproxen and treat a synthetic mixture from aqueous solutions. The material presented a highly porous texture, a surface area of 938 m2 g−1 , and certain functional groups, which were key factors to uptake naproxen from effluents. The maximum adsorption capacity predicted by the Langmuir model for naproxen was 176 mg g−1. The thermodynamic study revealed that the adsorption process was endothermic and spontaneous. The linear driving force (LDF) model presented a good statistical adjustment to the experimental decay data. A suitable interaction pathway of naproxen adsorption onto activated carbon was proposed. The adsorbent material was highly efficient to treat a synthetic mixture containing several drugs and salts, reaching 95.63% removal. Last, it was found that the adsorbent can be regenerated up to 7 times using an HCl solution. Overall, the results proved that the activated carbon derived from grape branches could be an effective and sustainable adsorbent to treat wastewaters containing drugs.

A series of geopolymers were synthesized from fly and bottom ashes of a thermoelectrical power plant located in the Brazilian southern, aiming to add value for these wastes. The geopolymers were prepared in conventional and ultrasound-assisted ways and used to uptake Ag+, Co2+, Cu2+, and Ni2+ from aqueous solutions. All materials were characterized by infrared spectroscopy (FT–IR), X-ray diffraction (XRD), and N2 adsorption isotherms (BET and BJH methods). The results revealed that the geopolymers obtained from the conventional method presented slightly higher values of surface area and total pore volume. However, in some cases, the adsorption potential was better for the ultrasound synthesized materials. The geopolymers prepared from both methods presented good adsorption performance concerning Ag+ and Cu2+, Co2+ and Ni2+. The removal percentages were higher than 90%. In addition, the adsorption capacities were within the literature range. These findings show that the ultrasound technique is not essential to improve the geopolymers production process compared to the conventional process, which generated material with better performance for heavy metals adsorption. Besides, it was possible to aggregate value for fly and bottom ashes, generating promising adsorbent materials.

Nanoscience and technology have enabled better insights into the environmental and health impacts arising from the mining, production and use of fossil and mineral fuels. Here we provide an overview of the nanoscience-based applications and discoveries concerning coal and mineral fuel (i.e., uranium-containing minerals) mining, refining/production, use, and disposal of wastes. These processes result in massive nanoparticle release and secondary nanoparticle generation which have highly significant environmental implications and human health consequences on local, regional, and even global levels. Until recently, very little was known about nanoparticle fractions. Recent advancements and sophistications enable us to detect, collect and study these materials which are roughly 1 nm (0.001 μm) up to several tens of nanometers in size. These materials are known to behave differently (chemically, electrically, and mechanically), relative to their macroscopic equivalents. This is what makes nanoscience fascinating and difficult to predict, underscoring the importance of this emerging new field. For example, nanoparticles associated with coal and mineral fuel influence the release, uptake, and transportation of hazardous elements associated with mining, processing, and waste storage in the surrounding areas. This includes long distance transport down streams, rivers, and eventually to oceans such as from coal and uranium mine drainages. In terms of human health, in all phases of mining, production/refining, use, and waste disposal, the associated nanoparticles can be acquired through oral ingestion, inhalation, and dermal absorption. Inhalation has been shown to be particularly damaging, where lung, heart, kidney, and brain diseases are prevalent. Relative to all other fields of science and engineering associated with coal and mineral fuel mining, production, use, and clean-up efforts, nanoscience, although a much newer field then the rest by comparison, is still greatly under-represented and under-utilized. There is also a continuing gap between what we so far know about the behavior of nanoparticles, and what remains to be discovered.

The influence of emissions of an active volcano on the composition of nanoparticles and ultrafine road dust was identified in an urban area of the Andes. Although many cities are close to active volcanoes, few studies have evaluated their influence in road dust composition. Air quality in urban areas is significantly affected by non-exhaust emissions (e.g. road dust, brake wear, tire wear), however, natural sources such as volcanoes also impact the chemical composition of the particles. In this study, elements from volcanic emissions such as Si > Al > Fe > Ca > K > Mg, and Sisingle bondAl with K were identified as complex hydrates. Similarly, As, Hg, Cd, Pb, As, H, Cd, Pb, V, and salammoniac were observed in nanoparticles and ultrafine material. Mineral composition was detected in the order of quartz > mullite > calcite > kaolinite > illite > goethite > magnetite > zircon > monazite, in addition to salammoniac, a tracer of volcanic sources. The foregoing analysis reflects the importance of carrying out more studies relating the influence of volcanic emissions in road dust in order to protect human health. The road dust load (RD10) ranged between 0.8 and 26.8 mg m-2 in the city.

The residual husks of the edible fruits of Psidium cattleianum were carbonized with FeCl3 as an activating agent and used as an adsorbent to remove the toxic herbicide. After the carbonization step, changes in the material’s structure were found. Activated carbon showed characteristics of microporous materials with a pore volume of 0.280 cm3 g−1 and surface area of 431 m2 g−1. Micrographs revealed the emergence of new cavities with a uniform and circular shape. The FTIR spectra showed the disappearance of some bands, remaining bands belonging to functional groups containing carbon, oxygen, and hydrogen. The XRD patterns confirmed the amorphous structure of the material even after the carbonization step, composed of amorphous graphitic carbon. EDS analysis showed that the carbon percentage increased and the oxygen decreased after the carbonization. The experiments were performed at neutral pH using 1 g L−1 of adsorbent. In equilibrium isotherms, the temperature played a considerable role in the adsorption capacity, increasing from 26.39 mg g−1 to 35.67 mg g−1 when the temperature varied from 298 to 328 K. The Liu isotherms were the ones that best fit the isotherm data. The changes in the adsorption enthalpy were endothermic (ΔH° 129.5 kJ mol−1). The general order kinetic model was the most adequate for kinetic data, presenting the lowest values of the Bayesian Information Criterion. Thus, activated carbon developed from the residues of the “araça” fruit showed promise in removing atrazine from aqueous solutions, with the great advantage of its high efficiency under neutral pH solutions and mild temperatures.

Sandwich panels (also known as insulated panels) have been traditionally used for industrial buildings and warehouses, but nowadays are being increasingly a favorable choice in building construction, mainly in wall cladding and roofing systems. This paper presents the results of an experimental and statistical comparative analysis of Fire Reaction development in sandwich panels consisting of steel sheeting and Polyisocyanurate (PIR) foam core. All these PIR core sandwich panels with joints kept the same dimensions (1000 mm × 1500 mm) + (500 mm × 1500 mm), but different thicknesses (30, 50, 100 and 150 mm). Five Single Burning Item (SBI) tests were carried out on individual PIR sandwich panels with vertical joints and their results were compared between themselves. It was possible to observe through an analysis of variance that there is an influence of the sample thickness in the individual results of the SBI test parameters; however, this variability has no significant influence on the Fire Reaction performance of the samples. Overall, the importance of these alternative sandwich panels is the increase in performance in the constructive processes and the offered comfort through its thermal insulation characteristics.

This work presents results of the first study of the variation by exposure to high temperatures from two stay-in-place polyvinyl chloride (SIP-PVC) formwork concrete exposed to the ISO 834 fire curve. A systematic sampling based on the proximity of the fire and the spalling of the concrete was carried out and microstructural, thermal, crystallographic and spectroscopic changes were studied according to the degree of affectation by fire using SEM, TGA-DTA, XRD and FTIR. The response to high temperature exposure of the microstructure of SIP-PVC formwork concrete after fire was established using the experimental results. Results show a relationship between the microstructure of concrete paste and exposure temperature, as well as, the relationship between exposure temperature and dehydration of calcium hydrates, CSH gel and Portlandite and decarbonation of Calcite. These reactions can be considered as tracers of the degree of exposure to high temperatures from stay-in-place PVC formwork concrete.

The morphology and composition of roots with different degrees of oxidation as a function of time were evaluated aiming to identify possible hazardous elements and nanoparticles. The roots were obtained from an abandoned coal mine located in the city of Criciuma, Santa Catarina, Brazil. From the roots, analyses were performed to identify nanoparticles (NPs) and ultrafine particles (UFPs), containing possible hazardous elements (PHEs) that cause potential environmental risks and impacts on human health. The identification of nanoscale materials requires greater robustness, so advanced integrated techniques have been used. The characterization of different types of roots was done by using focused ion beam (FIB), to evaluate nano-compound assemblies with high-resolution transmission electron microscopy/energy dispersive spectroscopy (HR-TEM/EDS). The results showed the presence of NPs containing Hg, Co, Cr, Ni, and V. The presence of these elements has increased consistently with the increase of C concentration in the roots, suggesting that the PHEs were gradually released from organic matter and inorganic minerals of coal. However, even with their decrease in roots, it was found that these elements still remained in the soil in significant quantities, even after 15 years of inactivation of the coal mine.

The chemical reactions of dry-disposed ash dump, ingressed oxygen, carbon dioxide, and infiltrating rainwater affect mineralogical transformation, redistribution, and migration of chemical species. Composite samples of weathered coal fly ash taken at various depths and fresh coal fly ash were examined using organic petrographic, X-ray diffraction, X-ray fluorescence techniques, and successive extraction procedures. Results obtained show relative enrichment of glass, Al–Fe-oxides, calcite, and tridymite in the weathered CFA, but the fresh CFA is enriched in mullite, inertinite, maghemite, and ettringite. The enrichment of the weathered CFA in amorphous glass suggests higher reactivity when compared to fresh CFA. The evident depletion of soluble oxides in the weathered CFA is attributed to flushing of the soluble salts by percolating rainwater. Comparative enrichment of examined elements in water-soluble, exchangeable, reducible, and residual fractions of the weathered CFA is partly due to the slow release of adsorbed chemical species from the alumina-silicate matrix and diffusion from the deeper sections of the particles of coal fly ash. Sodium and potassium show enrichment in the oxidisable fraction of fresh CFA. The estimated mobility factor indicates mobility for Ca, Mg, Na, Se, Mo, and Sb and K, Sr, V, Cu, Cr, Se, and B in fresh and weathered CFAs, respectively.

The PVSDM model was used for single and binary dye adsorption systems. This model is commonly used for adsorption in single systems, but this is the first time used in a binary mixture of dyes in the literature. To that end, a new adsorbent derived from Bauhinia forficata waste was created and described for eventual use in the treatment of a dye combination (methylene blue and crystal violet). The single and binary isotherms revealed that increasing the temperature decreases the methylene blue adsorption capacity while increasing the crystal violet adsorption capacity. The Langmuir and extended Langmuir models described the single and binary systems, respectively. Maximum adsorption capacities of 229.13 mg g−1 at 298 K for methylene blue and 324.12 mg g−1 at 328 K for crystal violet were obtained. The thermodynamic parameters showed that the adsorption process for both dyes is spontaneous, being exothermic for the methylene blue and endothermic for the crystal violet. Similar decay curves for the single and binary systems were observed. The PVSDM was able to describe both single and binary adsorption systems. The external mass transfer and the surface diffusion change according to the initial dye concentration and the system type (single or binary).

Assessing the physical, geographic, chemical, and geological aspects are important to understand environmental impacts as well as health concerns in view of building a more sustainable planet with circular economies that would last for the foreseeable future. In the recent years, the significance of incorporating ecosystem, anthropogenic activities, and climate has fortified from being an academic concern (e.g., WEF, 2011) into a broadly societal concern as the forecasted realities of environmental deterioration and global climate change come to pass, creating urgent public and environmental health issues. The degree and difficulty of these issues, especially within the broader narrative of a ballooning world population and unsustainable consumption patterns, need a harmonized, multidisciplinary, and global effort to increase public attentiveness, and also develop a reasonable response. Researchers, authorities, global managers, policy creators, international governments, stakeholders, and concerned citizens have become aware of the urgent need to address the profound and enduring challenges. In this context, nano-geoscience opens a new avenue to understand a wide range of environmental concerns. Markedly, the most important claims of nano-mineralogy are geared toward the ecologically benign effects of air quality, water, and soil

High amounts of phosphogypsum (PG) are generated in the production of phosphoric acid. Previous literature demonstrates that obtaining rare earth elements (REE) from PG is a promising alternative to managing this waste. However, the reported leaching efficiencies are low in most cases, or drastic leaching conditions are required. Therefore, this work aimed to study the leaching conditions of REE from PG to obtain high leaching efficiency values. Initially, a 24 factorial experimental design investigated the factors that affect the conventional acid leaching of REE from PG (leaching acid (citric and sulfuric acid), solid/liquid ratio, acid concentration, and temperature). Better leaching efficiency values of the sum of all REE (62.0% and 89.7% for citric and sulfuric acid, respectively) were obtained using an acid concentration of 3 mol L−1, solid/liquid ratio of 1/20 g mL−1, and temperature of 80 °C. Subsequently, the experiments optimization, performed through a central composite rotational design, indicated that the maximum leaching efficiency was achieved using a sulfuric acid concentration of 2.9 mol L−1, solid/liquid ratio of 1.7/20 g mL−1, and 55 °C. Under these conditions, the leaching efficiency of the sum of all REE was 90.0%. Leaching kinetics results showed that the equilibrium was reached in about 20 min for most REE. The mechanism investigation suggested that surface chemical reaction and diffusion through the boundary layer controlled the leaching.

Air pollution is a factor of concern on a global scale, accelerating the deterioration of historic medieval architecture and having harmful effects on human health. The general objective of this study is to understand the risks of atmospheric contamination that contribute to the degradation of the medieval historical heritage of (1) Bab El Bhar, (2) the Tunis Train Station and (3) the Bardo National Museum, in the City of Tunis, capital of Tunisia, located in North Africa. Sequentially, 64 samples were collected in SMPSs and 64 of dust particles in sites 1, 2 and 3, from 2015 to 2019. Field Emission Scanning Electron Microscopy (FE-SEM) was utilized together with High Resolution Transmission Electron Microscopy (HR-TEM) and the coupled with an Energy Dispersive X-ray (EDS), which allowed a better characterization and identification of NPs in images, using Energy Dispersive X-ray (EDS). The Bab El Bhar SMPS samples yielded a higher proportion of ultrafine and organic particles. Sedimented dusts showed high proportions of organometallic particles (Al, As, Ba, Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, S, Sb, Se, Si, Sn, Ti, V and Zn). The need to create public policies to protect both human health and physical historic infrastructure is noted, as this study identified dangerous elements harmful to human health in ultrafine particles, easily suspended by the wind and highly corrosive to historical buildings from the medieval period in the air of a busy metropolitan tourist site.

This work investigated the relation between direct band-gap conversion and excitation wavelength towards catalysis efficiency in red, green, and blue (RGB) light-emitting diode (LED) reactors. An integrating sphere and spectroradiometer system obtained the emission wavelengths of the operating modes spectra of the RGB-LED reactors. The effects of pH, catalyst, and H2O2 dosage were investigated, and the optimal photocatalysis conditions were found to be at pH 3, catalyst loading of 0.25 g L−1, 0.25 mmol L−1 of H2O2(aq) (30% v/v) for an initial model pollutant concentration of 75 mg L−1 and reaction time of 60 min. Under the higher intensity red mode (R1), the highest color removal rate was reached (88.1%), while in the conventional white light mode (WL), the decolorization efficiency remained 64.3%. Furthermore, the R1 mode showed a superior TOC removal than the WL mode, reaching the final removal efficiencies of 91.86% and 61.06%, respectively. Contrary to what has been reported, as the dominant wavelength of the irradiation source decreased, the efficiency also tended to decrease. The electron-hole recombination increased as the irradiation mode decreased, and a work function (φ) representing this phenomenon was obtained by the deduction of the relation between energy (E) and frequency (f) of the photons involved. Therefore, the insights presented in this work are valuable tools in increasing LED photocatalysis efficiency.

The increasing mortality of COVID-19 can aggravate soil contamination by metals, harmful to the health of the population, requiring new projects for future cemeteries capable of mitigating these impacts to the environment, justifying the importance of studying the concentrations of metals in the soil of urban cemeteries. The paper analyzed the levels of metals in the soil of urban cemeteries in the City of Carazinho, in the state of Rio Grande do Sul, located in southern Brazil, considering the increase in deaths by COVID-19, for the purpose of future projects for cemeteries aimed at mitigating the impacts generated on the environment. The soils of the three urban cemeteries in Carazinho were sampled, with 5 internal and external points, with 3 repetitions at depths of 0–20 and 20–40 cm, adding 180 samples to measure the concentrations of Fe, Mn, Cu, Zn, Cr and Pb (g kg−1), considering the analytical sequence: (1) analysis in triplicate with mean deviation (RDS); (2) R2 of the analytical curve; (3) traceability of the pattern of each metal; (4) quantification limit of each metal (QL), with the performance of nitroperchloric digestion of the samples and the determinations of metals by flame modality atomic absorption spectrometry. Quantitative data on deaths by COVID-19 were analyzed by univariate modeling of time series, in the integrated autoregressive moving averages model. The results of this study were made available to fifteen architects, who attributed future solutions for environmentally sustainable cemeteries. The results showed high levels of copper (Cu) and iron (Fe) in the soil of the cemeteries studied. Considering the increase in deaths and subsequent burials per COVID-19 revealed a prediction for the death toll of 6,082,306 for June 9, 2022, it is assumed that metal contamination can reach even higher levels. To mitigate these levels of contamination by metals, 80% of the architect respondents expressed their preference for a vertical cemetery, with treatment of gases and effluents to mitigate environmental impacts.

This work evaluated the potential of a synthesized faujasite-type zeolite Y as an adsorbent for the removal of relevant heavy metals such as silver (Ag+), copper (Cu2+), and cobalt (Co2+). The adsorption data of Ag+, Cu2+, and Co2+ ions were determined experimentally at pH 6 and temperatures of 298, 308, and 318 K. Two theoretical approaches have been applied based on statistical physics modeling and density functional theory (DFT) to understand and characterize the ion exchanges involved in the removal of all metals. Results showed that this zeolite was more efficient for the adsorption of Ag+ via cation-exchange. Based on the physical modelling, the removal of heavy metals on this zeolite was mono and multi-ionic (simple and multi-interactions), where the ions interacted via one and two adsorption sites. It was also noted that the temperature increment generated more available functional groups of the zeolite, facilitating the access to the smaller cavities and the interactions with the adsorbent. Adsorption energies for removing these metals with tested zeolite were slightly endothermic and were consistent with the typical values reported for ion exchange systems of heavy metals + zeolites. DFT results demonstrated that these cationic exchange energies depend on the nature of precursor salt, but with the same ranking. Both statistical and DFT approaches agreed that exchange Ag+ in zeolite Y was easier than Cu2+ and Co2+. Overall, the application of both theoretical approaches provided a reliable interpretation of the adsorption mechanism.

The present study verified the potential of volcanic rock powder residues originating from the extraction of semi-precious rocks in the state of Rio Grande do Sul, Brazil, as precursors or adsorbents for dyes and metallic ion removal from water. In this way, it is possible to add value and give an adequate destination to this waste. Volcanic rock powder residues from Ametista do Sul (AME) and Nova Prata (NP) were the starting materials. These were used naturally or submitted to the alkaline activation process at 60 °C and alkaline fusion at 550 °C. The analysis of the starting samples by X-ray fluorescence (XRF) revealed that they are mainly composed of aluminum, calcium, iron, and silicon oxides, which corroborates the presence of numerous crystalline phases observed in the X-ray diffraction spectra (XRD). Moreover, by XRD analysis of the synthesized samples, alkaline fusion proved to be more efficient in the dissolution of crystalline phases and consequently in the formation of the amorphous phase (more reactive). Furthermore, the adsorption tests with acid green and acid red dyes and Ag+, Co2+, and Cu2+ ions indicated the viability of using residual volcanic rock powder as raw material for the production of adsorbents functionalized with sodium hydroxide, being that the samples synthesized by alkaline fusion showed better results of removal and adsorption capacity for all the contaminants used in the study.

Graphical abstract, The global outbreak of coronavirus infectious disease-2019 (COVID-19) draws attentions in the transport and spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in aerosols, wastewater, surface water and solid wastes. As pathogens eventually enter the subsurface system, e.g., soils in the vadose zone and groundwater in the aquifers, they might survive for a prolonged period of time owing to the uniqueness of subsurface environment. In addition, pathogens can transport in groundwater and contaminate surrounding drinking water sources, possessing long-term and concealed risks to human society. This work critically reviews the influential factors of pathogen migration, unravelling the impacts of pathogenic characteristics, vadose zone physiochemical properties and hydrological variables on the migration of typical pathogens in subsurface system. An assessment algorithm and two rating/weighting schemes are proposed to evaluate the migration abilities and risks of pathogens in subsurface environment. As there is still no evidence about the presence and distribution of SARS-CoV-2 in the vadose zones and aquifers, this study also discusses the migration potential and behavior of SARS-CoV-2 viruses in subsurface environment, offering prospective clues and suggestions for its potential risks in drinking water and effective prevention and control from hydrogeological points of view.

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In this research, a functionalization of Physalis peruviana biomass with H2SO4 and its application in the adsorption of ketoprofen and 2,2-dichlorophenoxyactic acid is reported. In particular, the adsorption properties of this biomass were improved through a sulfuric acid treatment to enhance its removal performance of organic molecules. Surface chemistry of this modified biomass was also characterized. Experimental adsorption isotherms of these organic pollutants were determined at 298 – 328 K and pH 2. A multilayer statistical physics model was used in the data modeling to analyze the corresponding adsorption mechanism. Results showed that the endothermic multilayer adsorption of ketoprofen was a multi-molecular process where molecular aggregation could be expected. On the other hand, the adsorption of 2,2-dichlorophenoxyactic acid on this functionalized biomass was multi-anchoring. Adsorption energies (ΔE1) varied from 4.13 to 5.53 kJ/mol for KTP and from 7.54 to 7.96 kJ/mol for 2,4-D herbicide. These results showed that physical adsorption forces were involved in the removal of these organic molecules with this functionalized biomass because the adsorption energies < 40 kJ/mol.

Scientific works examining coal-derived nanoparticles (NPs) containing potentially toxic elements (PTEs) confined in marine suspended sediments (MSSs) in port regions worldwide is an understudied topic, despite the fact that coal NPs have tremendous negative impacts on marine estuaries. The general objective of this study is to analyze the NP levels of coal, including PTEs, contained within MSSs in the general vicinity of the largest Caribbean port in Colombia. The morphology, size, chemical composition, and agglomeration states of NPs within MSSs of the sampled beaches were calculated through modern electron microscopy. The methodology used to detect chemical elements, unfortunately with EDS, it is not possible to precisely specify the chemical elements of low atomic weight (e.g. H, O, F, etc.) Therefore, with the EDS available today, it is only possible to have an idea of the chemical composition of each detected particle. Thus, it was possible to obtain the average frequency of the chemical elements identified in the 23 analyzed sampling points. Through the results, more than one thousand particles were detected in the most abundant phases, thus, the most frequent particles in the results of this manuscript were described. Sample point 8, located closest to the coal export port, had a higher concentration of nano-toxic elements (Al, Fe, Si, K, Mg, K) most concerning for human health in addition to being harmful to marine life. This study suggests that public policies dealing with MSS pollution need to be discussed by public managers to avoid further and sustained environmental degradation. The need to create projects will subsidize legacy liabilities generated by coal in seaports in other regions of the world.

Road dust (RD) resuspension is one of the main sources of particulate matter in cities with adverse impacts on air quality, health, and climate. Studies on the variability of the deposited PM10 fraction of RD (RD10) have been limited in Latin America, whereby our understanding of the central factors that control this pollutant remains incomplete. In this study, forty-one RD10 samples were collected in two Andean cities (Bogotá and Manizales) and analyzed for ions, minerals, and trace elements. RD10 levels varied between 1.8–45.7 mg/m2, with an average of 11.8 mg/m2, in Bogotá and between 0.8–26.7 mg/m2, with an average of 5.7 mg/m2, in Manizales. Minerals were the most abundant species in both cities, with a fraction significantly larger in Manizales (38%) than Bogotá (9%). The difference could be explained mainly by the complex topography and the composition of soil derived from volcanic ash in Manizales. The volcanic activity was also associated with SO4−2 and Cl−. Enrichment factors and principal component analysis were conducted to explore potential factors associated to sources of RD10. Elements such as Cu, Pb, Cr, Ni, V, Sb, and Mo were mainly associated with exhaust and non-exhaust traffic emissions., The authors are grateful for the financial support provided by ECOPETROL and CORPOCALDAS. The authors’ viewpoint does not necessarily reflect the official opinion of their institutions. We thank our students from CLIMA Research Group and Hydraulic Engineering and Environmental Research Group who developed the field campaigns. In addition, we would like to thank Universidad Nacional de Costa Rica, who supported the chemical analysis of the road dust samples. The author Guilherme M. Pereira acknowledges the Brazilian foundation Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP, São Paulo Research Foundation; Grants nos. 2019/01316-8 and 2018/07848-9).

The paper presents a comparison of the concentration methods conventional jig, air jig, and sensor-based sorting to treat construction and demolition waste. All tests were made with concrete, brick, and gypsum particles and the tests aim to separate these materials into different size ranges, depending on the method. The equipment tested, conventional jig, air jig, and sensor-based sorting present good results to concentrate construction and demolition waste particles, with different concentrations and mass recoveries. The results show particularly good mass recoveries and particle concentration for conventional jig, especially for concrete and gypsum particles. Sensor-based sorting should preferably use concentration circuits for best results.

The analysis of marine matter using the Sentinel-3B OLCI (Ocean Land Color Instrument) satellite is the most advanced technique for evaluating: the absorption of colored detrital and dissolved material (ADG_443_NN), total suspended matter concentration (TSM_NN) and of chlorophyll-a (CHL_NN) on a global scale. The objective is to analyze ADG_443_NN, TSM_NN and CHL_NN using the Sentinel-3B OLCI satellite and the presence of Fe-nanoparticles (NPs) + hazardous elements (HEs) in suspended sediments (SSs) in the maritime estuary of the Colombian city of Barranquilla. The study used the unpublished image of the Sentinel-3B OLCI satellite in the evaluation of ADG_443_NN, TSM_NN and CHL_NN in 72 sampled points. Subsequently, 36 samples of SSs were carried out in the Magdalena River, in the identification of Fe-NPs by advanced electron microscopies. The Sentinel-3B satellite revealed particulate accumulations in OCE1 through the intensity of OLCI in ocean. There was also a high Fe-NPs intensity of SSs in the Magdalena channel, spreading contamination to large regions.

COVID-19 has escalated into one of the most serious crises in the 21st Century. Given the rapid spread of SARS-CoV-2 and its high mortality rate, here we investigate the impact and relationship of airborne PM2.5 to COVID-19 mortality. Previous studies have indicated that PM2.5 has a positive relationship with the spread of COVID-19. To gain insights into the delayed effect of PM2.5 concentration (μgm−3) on mortality, we focused on the role of PM2.5 in Wuhan City in China and COVID-19 during the period December 27, 2019 to April 7, 2020. We also considered the possible impact of various meteorological factors such as temperature, precipitation, wind speed, atmospheric pressure and precipitation on pollutant levels. The results from the Pearson's correlation coefficient analyses reveal that the population exposed to higher levels of PM2.5 pollution are susceptible to COVID-19 mortality with a lag time of >18 days. By establishing a generalized additive model, the delayed effect of PM2.5 on the death toll of COVID-19 was verified. A negative correction was identified between temperature and number of COVID-19 deaths, whereas atmospheric pressure exhibits a positive correlation with deaths, both with a significant lag effect. The results from our study suggest that these epidemiological relationships may contribute to the understanding of the COVID-19 pandemic and provide insights for public health strategies., Graphical abstract Unlabelled Image