Removal of chloroquine from the aqueous solution by adsorption onto açaí-based biochars: Kinetics, thermodynamics, and phytotoxicity

This study aimed at emerging contaminant chloroquine (CQN) removal, widely used in the COVID-19 pandemic through adsorption and employing a low-cost activated biochar from açai fruit endocarp. Two different adsorbents from the same precursor were applied. The first (CAA) was activated at a high temperature using ZnCl2, and the second (CA) was obtained by physical activation. The adsorbents were characterized through BET, FTIR, DRX, TG/DTG, and SEM. The results showed that zinc chloride activation furnished a material with a high specific surface area (SBET) and pore volume of 762 m2 g−1 and 0.098 cm3 g−1, respectively. Adsorption kinetics and isotherm were best adjusted through the pseudo-second-order (PSO) and Freundlich for both biochars. The process was thermodynamically favorable, occurring spontaneously without energy request. Additionally, the maximum adsorption capacity for CQN was 15.56 and 40.31 mg g−1 for CA and CAA, respectively, in pH 6.84, at a temperature of 25 °C, 50 mL solution and with 0.05 and 0.02 g of adsorbent. Those results are congruent with the literature showing the versatility of the material and the efficiency of the applied adsorption process.

Adsorption of the First-Line Covid Treatment Analgesic onto Activated Carbon from Residual Pods of Erythrina Speciosa.

In this study, the residual pods of the forest species Erythrina speciosa were carbonized with ZnCl2 to obtain porous activated carbon and investigated for the adsorptive removal of the drug paracetamol (PCM) from water. The PCM adsorption onto activated carbon is favored at acidic solution pH. The isothermal studies confirmed that increasing the temperature from 298 to 328 K decreased the adsorption capacity from 65 mg g-1 to 50.4 mg g-1 (C0 = 175 mg L-1). The Freundlich model showed a better fit of the equilibrium isotherms. Thermodynamic studies confirmed the exothermic nature (ΔH0 = -39.1066 kJ mol-1). Kinetic data indicates that the external mass transfer occurs in the first minutes followed by the surface diffusion, considering that the linear driving force model described the experimental data. The application of the material in the treatment of a simulated effluent with natural conditions was promising, presenting a removal of 76.45%. Therefore, it can be concluded that the application of residual pods of the forest species Erythrina speciosa carbonized with ZnCl2 is highly efficient in the removal of the drug paracetamol and also in mixtures containing other pharmaceutical substances.

Air pollution in central European capital (Budapest) via self-made passive samplers and Sentinel-3B SYN satellite images

This study is to identify the types of ultra-fine air pollutants present in the local atmosphere. The authors utilize Sentinel-3B SYN satellite images to identify the presence of Aerosol Optical Thickness (T550), and later verify this presence through physical sample collection using self-made passive samplers (SMPSs) at various locations in Budapest ((A) Passenger Cruise Port, (B) Kunsthalle, (C) Szechenyi Lanchid, and (D) Liberty Bridge). The samples obtained from the SMPSs were analyzed by X-ray Diffraction (XRD) to identify the minerals present in ultra-fine phases (e.g. minerals and ultra-fine amorphous). The images from the Sentinel-3B SYN satellite, taken between 2018, 2019 and 2021 allowed us to identify the Aerosol Optical Thickness (T550) at these same locations in Budapest. The SMPS samples revealed the presence of ultra-fine particles containing elements dangerous to human health, such as: As, Cd, Cr, Hg, Pb, Ti, V and Ni. The points analyzed in the Sentinel-3B SYN satellite images showed a 50.89% reduction in T550 levels in the city of Budapest, attributed to the COVID-19 epidemic, which clearly demonstrates the need to reduce pollutants for a better quality of life in this central capital of Europe.

Air Quality Changes during the COVID-19 Lockdown in an Industrial City in North China: Post-Pandemic Proposals for Air Quality Improvement

To better understand the changes in air pollutants in an industrial city, Handan, North China, during the COVID-19 lockdown period, the air quality and meteorological conditions were recorded from 1 January to 3 March 2020 and the corresponding period in 2019. Compared to the corresponding period in 2019, the largest reduction in PM2.5–10, PM2.5, NO2 and CO occurred during the COVID-19 lockdown period. PM2.5–10 displayed the highest reduction (66.6%), followed by NO2 (58.4%) and PM2.5 (50.1%), while O3 increased by 13.9%. Similarly, compared with the pre-COVID-19 period, NO2 significantly decreased by 66.1% during the COVID-19 lockdown, followed by PM2.5–10 (45.9%) and PM2.5 (42.4%), while O3 increased significantly (126%). Among the different functional areas, PM2.5 and PM2.5–10 dropped the most in the commercial area during the COVID-19 lockdown. NO2 and SO2 decreased the most in the traffic and residential areas, respectively, while NO2 increased only in the township and SO2 increased the most in the industrial area. O3 increased in all functional areas to different extents. Potential source contribution function analysis indicated that not only the local air pollution lessened, but also long-distance or inter-regional transport contributed much less to heavy pollution during the lockdown period. These results indicate that the COVID-19 lockdown measures led to significantly reduced PM and NO2 but increased O3, highlighting the importance of the synergetic control of PM2.5 and O3, as well as regional joint prevention and the control of air pollution. Moreover, it is necessary to formulate air pollution control measures according to functional areas on a city scale.

Physiological characteristics, geochemical properties and hydrological variables influencing pathogen migration in subsurface system: What we know or not?

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.

COVID-19 mortality and exposure to airborne PM2.5: A lag time correlation.

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.

Metals in the soil of urban cemeteries in Carazinho (South Brazil) in view of the increase in deaths from COVID-19: projects for cemeteries to mitigate environmental impacts.

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.

The role of airborne particles and environmental considerations in the transmission of SARS-CoV-2

Corona Virus Disease 2019 (COVID-19) caused by the novel coronavirus, results in an acute respiratory condition coronavirus 2 (SARS-CoV-2) and is highly infectious. The recent spread of this virus has caused a global pandemic. Currently, the transmission routes of SARS-CoV-2 are being established, especially the role of environmental transmission. Here we review the environmental transmission routes and persistence of SARS-CoV-2. Recent studies have established that the transmission of this virus can occur, amongst others, in the air, water, soil, cold-chain, biota, and surface contact. It has also been found that the survival potential of the SARS-CoV-2 virus is dependent on different environmental conditions and pollution. Potentially important pathways include aerosol and fecal matter. Particulate matter may also be a carrier for SARS-CoV-2. Since microscopic particles can be easily absorbed by humans, more attention must be focused on the dissemination of these particles. These considerations are required to evolve a theoretical platform for epidemic control and to minimize the global threat from future epidemics.

Multiple relationships between aerosol and COVID-19: A framework for global studies.

COVID-19 (Corona Virus Disease 2019) is a severe respiratory syndrome currently causing a human global pandemic. The original virus, along with newer variants, is highly transmissible. Aerosols are a multiphase system consisting of the atmosphere with suspended solid and liquid particles, which can carry toxic and harmful substances; especially the liquid components. The degree to which aerosols can carry the virus and cause COVID-19 disease is of significant research importance. In this study, we have discussed aerosol transmission as the pathway of SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2), and the aerosol pollution reduction as a consequence of the COVID-19 lockdown. The aerosol transmission routes of the SARS-CoV-2 can be further subdivided into proximal human-exhaled aerosol transmission and potentially more distal ambient aerosol transmission. The human-exhaled aerosol transmission is a direct dispersion of the SARS-CoV-2. The ambient aerosol transmission is an indirect dispersion of the SARS-CoV-2 in which the aerosol acts as a carrier to spread the virus. This indirect dispersion can also stimulate the up-regulation of the expression of SARS-CoV-2 receptor ACE-2 (Angiotensin Converting Enzyme 2) and protease TMPRSS2 (Transmembrane Serine Protease 2), thereby increasing the incidence and mortality of COVID-19. From the aerosol quality data around the World, it can be seen that often atmospheric pollution has significantly decreased due to factors such as the reduction of traffic, industry, cooking and coal-burning emissions during the COVID-19 lockdown. The airborne transmission potential of SARS-CoV-2, the infectivity of the virus in ambient aerosols, and the reduction of aerosol pollution levels due to the lockdowns are crucial research subjects.