Disposable Polypropylene Face Masks: A Potential Source of Micro/Nanoparticles and Organic Contaminates in Humans.

We have been effectively protected by disposable propylene face masks during the COVID-19 pandemic; however, they may pose health risks due to the release of fine particles and chemicals. We measured micro/nanoparticles and organic chemicals in disposable medical masks, surgical masks, and (K)N95 respirators. In the breathing-simulation experiment, no notable differences were found in the total number of particles among mask types or between breathing intensities. However, when considering subranges, <2.5 µm particles accounted for ∼90% of the total number of micro/nanoparticles. GC-HRMS-based suspect screening tentatively revealed 79 (semi)volatile organic compounds in masks, with 18 being detected in ≥80% of samples and 44 in ≤20% of samples. Three synthetic phenolic antioxidants were quantified, and AO168 reached a median concentration of 2968 ng/g. By screening particles collected from bulk mask fabrics, we detected 18 chemicals, including four commonly detected in masks, suggesting chemical partition between the particles and the fabric fibers and chemical exposure via particle inhalation. These particles and chemicals are believed to originate from raw materials, intentionally and nonintentionally added substances in mask production, and their transformation products. This study highlights the need to study the long-term health risks associated with mask wearing and raises concerns over mask quality control.

A simplified viral RNA extraction method based on magnetic nanoparticles for fast and high-throughput detection of SARS-CoV-2.

The ongoing outbreak of the novel coronavirus disease 2019 (COVID-19) draws worldwide concerns due to its long incubation period and strong infectivity. Although RT-PCR-based methods are being widely applied for clinical diagnosis, timely and accurate diagnosis towards COVID-19 causing virus, the SARS-CoV-2, is still limited due to labor-intensive and time-consuming operations. Herein, we report a new viral RNA extraction method based on poly-(amino ester) with carboxyl group (PC)-coated magnetic nanoparticles (pcMNPs) for the sensitive detection of SARS-CoV-2. This method combines the lysis and binding steps into one step, and refines multiple washing steps into one step, giving a turnaround time of less than 9 min. Furthermore, the extracted pcMNP-RNA complexes can be directly introduced into subsequent RT-PCR reactions without elution. This simplified viral RNA method could be well adapted in fast manual and automated high-throughput nucleic acids extraction protocols suitable for different scenarios. A high sensitivity down to 100 copies/mL and a linear correlation between 100 and 106 copies/mL of SARS-CoV-2 pseudovirus particles are achieved in both protocols. Benefitting from the simplicity and excellent performances, this new method can dramatically improve the efficiency and reduce operational requirements for the early clinical diagnosis and large-scale SARS-CoV-2 nucleic acid screening.

COVID-19 Pandemic Impacts on Humans Taking Antibiotics in China.

The outbreak of the novel coronavirus 2019 (COVID-19) pandemic has resulted in the increased human consumption of medicines. Antibiotics are of great concern due to their adverse effects, such as increased bacterial resistance and dysbiosis of gut microbiota. Nevertheless, very little is known about the changes in self-medication with antibiotics during the COVID-19 pandemic and the resultant potential health risks. Herein, we examined the concentration profiles of some commonly used antibiotics in human urine collected from several geographical regions in China between 2020 and 2021. Antibiotics were found in 99.2% of the urine samples at concentrations ranging from not detected (nd) to 357 000 (median: 10.2) ng/mL. During the COVID-19 pandemic, concentrations of urinary antibiotics were remarkably higher than those found either before the pandemic or in the smooth period of the pandemic. Moreover, elevated levels of antibiotics were determined in urine samples from the regions with more confirmed cases. The exposure assessment showed that hazard index values >1 were determined in 35.2% of people. These findings show that human exposure to antibiotics increased during the COVID-19 pandemic, and further research is imperative to identify the public health risks.

Paper Device Combining CRISPR/Cas12a and Reverse-Transcription Loop-Mediated Isothermal Amplification for SARS-CoV-2 Detection in Wastewater.

Wastewater-based surveillance of the COVID-19 pandemic holds great promise; however, a point-of-use detection method for SARS-CoV-2 in wastewater is lacking. Here, a portable paper device based on CRISPR/Cas12a and reverse-transcription loop-mediated isothermal amplification (RT-LAMP) with excellent sensitivity and specificity was developed for SARS-CoV-2 detection in wastewater. Three primer sets of RT-LAMP and guide RNAs (gRNAs) that could lead Cas12a to recognize target genes via base pairing were used to perform the high-fidelity RT-LAMP to detect the N, E, and S genes of SARS-CoV-2. Due to the trans-cleavage activity of CRISPR/Cas12a after high-fidelity amplicon recognition, carboxyfluorescein-ssDNA-Black Hole Quencher-1 and carboxyfluorescein-ssDNA-biotin probes were adopted to realize different visualization pathways via a fluorescence or lateral flow analysis, respectively. The reactions were integrated into a paper device for simultaneously detecting the N, E, and S genes with limits of detection (LODs) of 25, 310, and 10 copies/mL, respectively. The device achieved a semiquantitative analysis from 0 to 310 copies/mL due to the different LODs of the three genes. Blind experiments demonstrated that the device was suitable for wastewater analysis with 97.7% sensitivity and 82% semiquantitative accuracy. This is the first semiquantitative endpoint detection of SARS-CoV-2 in wastewater via different LODs, demonstrating a promising point-of-use method for wastewater-based surveillance.

The adverse inflammatory response of tobacco smoking in COVID-19 patients: biomarkers from proteomics and metabolomics.

Whether tobacco smoking affects the occurrence and development of coronavirus disease 2019 (COVID-19) is still a controversial issue, and potential biomarkers to predict the adverse outcomes of smoking in the progression of COVID-19 patients have not yet been elucidated. To further uncover their linkage and explore the effective biomarkers, three proteomics and metabolomics databases (i.e. smoking status, COVID-19 status, and basic information of population) from human serum proteomic and metabolomic levels were established by literature search. Bioinformatics analysis was then performed to analyze the interactions of proteins or metabolites among the above three databases and their biological effects. Potential confounding factors (age, body mass index (BMI), and gender) were controlled to improve the reliability. The obtained data indicated that smoking may increase the relative risk of conversion from non-severe to severe COVID-19 patients by inducing the dysfunctional immune response. Seven interacting proteins (C8A, LBP, FCN2, CRP, SAA1, SAA2, and VTN) were found to promote the deterioration of COVID-19 by stimulating the complement pathway and macrophage phagocytosis as well as inhibiting the associated negative regulatory pathways, which can be biomarkers to reflect and predict adverse outcomes in smoking COVID-19 patients. Three crucial pathways related to immunity and inflammation, including tryptophan, arginine, and glycerophospholipid metabolism, were considered to affect the effect of smoking on the adverse outcomes of COVID-19 patients. Our study provides novel evidence and corresponding biomarkers as potential predictors of severe disease progression in smoking COVID-19 patients, which is of great significance for preventing further deterioration in these patients.

Front Cover: Computational Insights into the Allosteric Effect and Dynamic Structural Features of the SARS‐COV‐2 Spike Protein (Chem. Eur. J. 6/2022)

Although the prefusion conformation of the spike protein of SARS‐COV‐2 can be stabilized alone, a spontaneously and energy‐friendly centripetal movement of the receptor binding domain occurs when spike protein binds to ACE2. During the binding process, several residues, especially Phe329 and Phe515, play a significant role in the allosteric effect. As a result, two potential cleavage sites S1/S2 and S2′ are exposed on the surface. More information can be found in the Research Article by A. Zhang, J. Fu et al. (DOI: 10.1002/chem.202104215).

A pandemic-induced environmental dilemma of disposable masks: solutions from the perspective of the life cycle.

The coronavirus disease 2019 (COVID-19) has swept the world and still afflicts humans. As an effective means of protection, wearing masks has been widely adopted by the general public. The massive use of disposable masks has raised some emerging environmental and bio-safety concerns: improper handling of used masks may transfer the attached pathogens to environmental media; disposable masks mainly consist of polypropylene (PP) fibers which may aggravate the global plastic pollution; and the risks of long-term wearing of masks are elusive. To maximize the utilization and minimize the risks, efforts have been made to improve the performance of masks (e.g., antivirus properties and filtration efficiency), extend their functions (e.g., respiration monitoring and acting as a sampling device), develop new disinfection methods, and recycle masks. Despite that, from the perspective of the life cycle (from production, usage, and discard to disposal), comprehensive solutions are urgently needed to solve the environmental dilemma of disposable masks in both technologies (e.g., efficient use of raw materials, prolonging the service life, and enabling biodegradation) and policies (e.g., stricter industry criteria and garbage sorting).

Antiviral Properties of Silver Nanoparticles against SARS-CoV-2: Effects of Surface Coating and Particle Size.

Coronavirus disease 2019 (COVID-19) has spread rapidly and led to over 5 million deaths to date globally. Due to the successively emerging mutant strains, therapeutics and prevention against the causative virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are urgently needed. Prevention of SARS-CoV-2 infection in public and hospital areas is essential to reduce the frequency of infections. Silver nanoparticles (AgNPs) with virucidal effects have been reported. Therefore, we investigated the virucidal activity and safety of ten types of AgNPs with different surface modifications and particle sizes, in cells exposed to SARS-CoV-2 in vitro. The AgNPs could effectively inhibit the activity of SARS-CoV-2, and different surface modifications and particle sizes conferred different virucidal effects, of which 50-nm BPEI showed the strongest antiviral effect. We concluded that the efficacy of each type of AgNP type was positively correlated with the corresponding potential difference (R2 = 0.82). These in vitro experimental data provide scientific support for the development of therapeutics against COVID-19, as well as a research basis for the development of broad-spectrum virucides. Given the increasing acquired resistance of pathogens against conventional chemical and antibody-based drugs, AgNPs may well be a possible solution for cutting off the route of transmission, either as an external material or a potential medicine.

Computational Insights into the Allosteric Effect and Dynamic Structural Features of the SARS-COV-2 Spike Protein.

Invited for the cover of this issue are Aiqian Zhang, Jianjie Fu, Guibin Jiang, and co-workers at the Chinese Academy of Sciences. The image depicts the molecular recognition of human angiotensin-converting enzyme 2 by the SARS-COV-2 spike protein. Read the full text of the article at 10.1002/chem.202104215.

Exogenous Chemical Exposure Increased Transcription Levels of the Host Virus Receptor Involving Coronavirus Infection.

Virus receptors are highly involved in mediating the entrance of infectious viruses into host cells. Here, we found that typical chemical exposure caused the upregulation of virus receptor mRNA levels. Chemicals with the same structural characteristics can affect the transcription of angiotensin-converting enzyme 2 (ACE2), a dominant receptor of SARS-CoV-2. Some chemicals can also regulate the transcription of ACE2 by similar regulatory mechanisms, such as multilayer biological responses and the crucial role of TATA-box binding protein associated factor 6. The abovementioned finding suggested that chemical mixtures may have a joint effect on the ACE2 mRNA level in the real scenario, where humans are exposed to numerous chemicals simultaneously in daily life. Chemically regulated virus receptor transcription was in a tissue-dependent manner, with the highest sensitivity in pulmonary epithelial cells. Therefore, in addition to genetic factors, exogenous chemical exposure can be an emerging nongenetic factor that stimulates the transcription of virus receptor abundance and may elevate the protein expression. These alterations could ultimately give rise to the susceptibility to virus infection and disease severity. This finding highlights new requirements for sufficient epidemiological data about exposomes on pathogen receptors in the host.

New Insights into Unexpected Severe PM2.5 Pollution during the SARS and COVID-19 Pandemic Periods in Beijing.

During the SARS period in 2003 and COVID-19 pandemic period in 2020, unexpected severe particulate matter pollution occurred in northern China, although the anthropogenic activities and associated emissions have assumed to be reduced dramatically. This anomalistic increase in PM2.5 pollution raises a question about how source emissions impact the air quality during these pandemic periods. In this study, we investigated the stable Cu and Si isotopic compositions and typical source-specific fingerprints of PM2.5 and its sources. We show that the primary PM2.5 emissions (PM2.5 emitted directly from sources) actually had no reduction but redistribution during these pandemic periods, rather than the previous thought of being greatly reduced. This finding provided critical evidence to interpret the anomalistic PM2.5 increase during the pandemic periods in north China. Our results also suggested that both the energy structure adjustment and stringent regulations on primary emissions should be synergistically implemented in a regional scale for clean air actions in China.

COVID-19-Induced Lockdowns Indicate the Short-Term Control Effect of Air Pollutant Emission in 174 Cities in China.

The contradiction between the regional imbalance and an one-size-fits-all policy is one of the biggest challenges in current air pollution control in China. With the recent implementation of first-level public health emergency response (FLPHER) in response to the COVID-19 pandemic in China (a total of 77 041 confirmed cases by February 22, 2020), human activities were extremely decreased nationwide and almost all economic activities were suspended. Here, we show that this scenario represents an unprecedented "base period" to probe the short-term emission control effect of air pollution at a city level. We quantify the FLPHER-induced changes of NO2, SO2, PM2.5, and PM10 levels in 174 cities in China. A machine learning prediction model for air pollution is established by coupling a generalized additive model, random effects meta-analysis, and weather research and forecasting model with chemistry analysis. The short-term control effect under the current energy structure in each city is estimated by comparing the predicted and observed results during the FLPHER period. We found that the short-term emission control effect ranges within 53.0%-98.3% for all cities, and southern cities show a significantly stronger effect than northern cities (P < 0.01). Compared with megacities, small-medium cities show a similar control effect on NO2 and SO2 but a larger effect on PM2.5 and PM10.

Occurrence and Distribution of Disinfection Byproducts in Domestic Wastewater Effluent, Tap Water, and Surface Water during the SARS-CoV-2 Pandemic in China.

Intensified efforts to curb transmission of the Severe Acute Respiratory Syndrome Coronavirus-2 might lead to an elevated concentration of disinfectants in domestic wastewater and drinking water in China, possibly resulting in the generation of numerous toxic disinfection byproducts (DBPs). In this study, the occurrence and distribution of five categories of DBPs, including six trihalomethanes (THMs), nine haloacetic acids (HAAs), two haloketones, nine nitrosamines, and nine aromatic halogenated DBPs, in domestic wastewater effluent, tap water, and surface water were investigated. The results showed that the total concentration level of measured DBPs in wastewater effluents (78.3 µg/L) was higher than that in tap water (56.0 µg/L, p = 0.05), followed by surface water (8.0 µg/L, p < 0.01). Moreover, HAAs and THMs were the two most dominant categories of DBPs in wastewater effluents, tap water, and surface water, accounting for >90%, respectively. Out of the regulated DBPs, none of the wastewater effluents and tap water samples exceeded the corresponding maximum guideline values of chloroform (300 µg/L), THM4 (80 µg/L), NDMA (100 ng/L), and only 2 of 35 tap water samples (67.6 and 63.3 µg/L) exceeded the HAA5 (60 µg/L) safe limit. HAAs in wastewater effluents showed higher values of risk quotient for green algae. This study illustrates that the elevated use of disinfectants within the guidance ranges during water disinfection did not result in a significant increase in the concentration of DBPs.

Inherited and acquired corona of coronavirus in the host: Inspiration from the biomolecular corona of nanoparticles.

The family of coronavirus are named for their crown shape. Encoded by the genetic material inherited from the coronavirus itself, this intrinsic well-known "viral corona" is considered an "inherited corona". After contact with mucosa or the entrance into the host, bare coronaviruses can become covered by a group of dissolved biomolecules to form one or multiple layers of biomolecules. The layers acquired from the surrounding environment are named the "acquired corona". We highlight here the possible role of the acquired corona in the pathogenesis of coronaviruses, which will generate fresh insight into the nature of various coronavirus-host interactions.

Detection of coronavirus in environmental surveillance and risk monitoring for pandemic control.

The novel human infectious coronaviruses (CoVs) responsible for severe respiratory syndromes have raised concerns owing to the global public health emergencies they have caused repeatedly over the past two decades. However, the ongoing coronavirus disease 2019 (COVID-19) pandemic induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has received unprecedented attention internationally. Monitoring pathogenic CoVs in environmental compartments has been proposed as a promising strategy in preventing the environmental spread and tracing of infectious diseases, but a lack of reliable and efficient detection techniques is still a significant challenge. Moreover, the lack of information regarding the monitoring methodology may pose a barrier to primary researchers. Here, we provide a systematic introduction focused on the detection of CoVs in various environmental matrices, comprehensively involving methods and techniques of sampling, pretreatment, and analysis. Furthermore, the review addresses the challenges and potential improvements in virus detection techniques for environmental surveillance.