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The synthesis and employment of volatile toxic compounds as chemical weapons with a large-scale destructive power has introduced a new insidious threat over the last century. In this framework, the development of wearable sensing tools represents a critical point within the security field, in order to provide early alarm systems. Herein, a novel wearable electrochemical biosensor was developed for the rapid and on-site detection of mustard agents. Since a chemical attack is typically carried out by spraying these volatile agents into air, the sensor was designed in order to be able to measure mustard agents directly in the aerosol phase, further than in the liquid phase. The electrodes were screen-printed onto a filter paper support, which allowed to harness the porosity of paper to pre-load all the needed reagents into the cellulose network, and hence to realise an origami-like and reagent-free device. Mustard agent detection was carried out by monitoring their inhibitory effects toward the choline oxidase enzyme, through the amperometric measurement of the enzymatic by-product hydrogen peroxide. A carbon black/Prussian blue nanocomposite was used as a bulk-modifier of the conductive graphite ink constituting the working electrode, allowing for the electrocatalysis of the hydrogen peroxide reduction. After having verified the detecting capability toward a mustard agent simulant, the applicability of the resulting origami-like biosensor was demonstrated for the rapid and real-time detection of real sulfur mustard, obtaining limits of detection equal to 1 mM and 0.019 g·min/m3 for liquid and aerosol phase, respectively.

Facemasks are considered safe and wearable devices that cover the human mouth and nose for filtering exhaled aerosols and inhaled environmental exposures; various chemical and environmental residues thus can remain in facemasks. Therefore, direct analysis of residues in facemasks can be used to investigate the wearer's health and behavior. Here, we developed a simple paper-in-facemask sampling method for adsorbing a wearer's respiratory aerosol and environmental exposures by fixing paper strips at the outside and inside surfaces of facemasks, and the paper strips were then analyzed by paper spray mass spectrometry (PSMS) for directly detecting adsorbed analytes without any sample pretreatment. The applicability of this device was demonstrated by directly analyzing exhaled aerosolized saliva, breath metabolites, and inhalable environmental exposures. The technical aspects, including sampling time, sampling position, paper property, and spray solvent, were investigated. The sampling process was revealed to involve a continuous-flow adsorptive mechanism. These findings motivated us to extend this work and build a wearable sampling device that is capable of simultaneously monitoring both exhaled and inhaled biomarkers in situ to investigate human health and environmental exposure. This work highlights that facemasks are promising platforms for aerosol collection and direct MS analysis, which is expected to be a promising method for monitoring human health, diseases, and behaviors.

SARS, a new type of respiratory disease caused by SARS-CoV, was identified in 2003 with significant levels of morbidity and mortality. The recent pandemic of COVID-19, caused by SARS-CoV-2, has generated even greater extents of morbidity and mortality across the entire world. Both SARS-CoV and SARS-CoV-2 spreads through the air in the form of droplets and potentially smaller droplets (aerosols) via exhaling, coughing, and sneezing. Direct detection from such airborne droplets would be ideal for protecting general public from potential exposure before they infect individuals. However, the number of viruses in such droplets and aerosols is too low to be detected directly. A separate air sampler and enough collection time (several hours) are necessary to capture a sufficient number of viruses. In this work, we have demonstrated the direct capture of the airborne droplets on the paper microfluidic chip without the need for any other equipment. 10% human saliva samples were spiked with the known concentration of SARS-CoV-2 and sprayed to generate liquid droplets and aerosols into the air. Antibody-conjugated submicron particle suspension is then added to the paper channel, and a smartphone-based fluorescence microscope isolated and counted the immunoagglutinated particles on the paper chip. The total capture-to-assay time was

Exposure to trace metals in airborne particulate matter (PM) has been linked to various adverse health effects. Quantifying metals in PM is important; however, current analytical tools tend to be bulky and expensive. A need therefore exists for more rapid, low-cost, portable tools for multiplexed determination of metals in PM. Electrochemical paper-based devices (ePADs) have been used for detecting metals in PM but require different devices and methods for different metals, making the systems more complicated than desired. Recently reported Janus ePADs offer a solution to this problem by allowing for multiple electrochemical experiments from a single sample. Here, we sought to determine if a Janus ePAD containing four independent channels and working electrodes could be used for simultaneous detection of multiple metals in PM. Online sample pretreatment in each channel during sample delivery yielded optimal conditions for each experiment. The design allows the device to conduct square-wave anodic stripping voltammetry (SWASV) and square-wave cathodic stripping voltammetry (SWCSV) for simultaneous detection of Cd, Pb, Cu, Fe, and Ni from a single sample. Two detection zones each with shared reference and counter electrodes were used for SWASV and SWCSV, respectively. The proposed sensors reached LODs down to 0.5, 0.5, 1.0, 0.5, and 1.0 μg L

Immunoassays and high-performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) are both widely used methods for drug screening in toxicology. We investigated an alternative approach for rapid drug screening: paper spray MS (PS-MS). In paper spray, the biofluid sample is spotted onto a paper substrate. Upon application of a spray solvent and an electric potential, extraction and ionization occur directly from the paper without any need for additional sample preparation. We developed two paper spray high-resolution MS/MS targeted drug screening assays using a quadrupole-orbitrap mass spectrometer, one the positive ion mode and one in the negative ion mode. In the positive ion mode, over 130 drugs and drug metabolites were semi-quantitatively screened at sub-toxic concentrations in a single 2.5 min analysis. Limits of detection and calibration performances for each target compound are reported. The PS-MS/MS assay was tested on authentic postmortem specimens, and its screening ability and semi-quantitative performance were evaluated against independent LC-MS-MS screening and confirmation assays with good agreement. The paper spray MS/MS showed good qualitative agreement with LC-MS-MS; the true positive rate of paper spray MS/MS was 92%, and the true negative rate was over 98%. The quantitative results between the two methods were also acceptable for a screening application; Passing-Bablok regression yielded a slope of 1.17 and a Pearson's correlation coefficient of 0.996. A separate PS-MS/MS negative ion screening method was also developed for a small panel of barbiturates and structural analogs, demonstrating its potential for acidic drug detection and screening.

Thermal papers (e.g. point of sale receipts, adhesive labels, tickets) significantly contribute to contamination of paper material cycles and the environment with substances of (eco-) toxicological concern. In particular, they contain color developers like endocrine disrupting bisphenols in typical concentrations of about 1–2 percent per weight (wt%). Bisphenol A (BPA) was used as the common color developer over the last decades, but it will be restricted for thermal paper application in the European Union to a limit of 0.02 wt% from 2020 onwards. Consequently, a variety of BPA substituents such as bisphenol S (BPS) and its derivatives gain importance in thermal paper application. In this study, a rapid, reliable and cost-effective method for identification and quantification of BPA, alternative color developers and related substances like sensitizers is presented based on HPLC separation coupled with diode array detection (DAD) and Corona charged aerosol detection (CAD). Quantification was performed with regard to the intended use of the substances in thermal papers. Besides traditional UV external calibration using reference standards, alternative quantification approaches, in particular UV chromophore concentration for BPS derivatives and CAD universal response technique for low-volatile color developers, were applied and compared in order to allow quantification without reference substances. A market analysis for intended used color developers and sensitizers was performed on thermal paper samples (n = 211) collected in Germany during 2018 and 2019. Pergafast 201 (in 41.7% of the samples) was the most common color developer with concentrations above 0.02 wt%, followed by BPA (36.0%), BPS (13.3%) and other BPS derivatives known as D8, D-90, BPS-MAE and TGSA, that are mainly present in adhesive labels. Sensitizers were determined in over 90% of the samples.

Conventional airborne virus measurement usually requires appreciable sampling and detection times. Viral aerosols should also be collected or prepared in a liquid medium whose volume typically ranges from milliliters to tens of milliliters; hence, many sampling and detection steps need to be taken with the unit horizontal or immobile. Moreover, viral aerosols need to be sufficiently enriched, which makes real-time monitoring difficult. Herein, we present a near real-time enrichment and quantification system of airborne viruses that consists of a wet-paper-based electrochemical immunosensor with a gel electrolyte and a modified electrostatic particle concentrator. A small amount of phosphate-buffered saline flowed on the electrode, which resulted in sensor electrodes that are barely wet (covered in a thin buffer film measuring several micrometers) to ensure antigen-antibody interaction and the removal of non-target particles on the electrode surface. This system ensures that airborne viruses are highly enriched on the working electrode of the immunosensor, and it is possible to measure the MS2 virus particle concentrations every 10 min for 60 min stably and selectively against non-target airborne viruses and bacteria at horizontal and tilted measurement configurations. This system thus has the potential to be used in the real-time mobile monitoring of airborne microorganisms.

Pesticides are largely used at worldwide level to improve food production, fulfilling the needs of the global population which is increasing year by year. Although pesticides are beneficial for crop production, their extensive use has serious consequences for the pollution of the produced food as well as for soil and groundwaters. Indeed, it is reported that 50% of sprayed pesticides reach different destinations other than their target species, including soil, surface waters, and groundwaters. For this reason, we developed a flower-like origami paper-based device for pesticides detection in aerosol phase for precision agriculture. In detail, the paper-based electrochemical platform detects paraoxon, 2,4-dichlorophenoxyacetic acid, and glyphosate at ppb levels by measuring their inhibitory activity towards three different enzymes namely butyrylcholinesterase, alkaline phosphatase, and peroxidase enzyme, respectively. This integrated electrochemical device is composed of three office paper-based screen-printed electrodes and filter paper-based pads loaded with enzymes and enzymatic substrates. The pesticide detection is carried out by measuring through chronoamperometric technique the initial and residual enzymatic activity by using a smartphone-assisted potentiostat and evaluating the percentage of inhibition, proportional to the amount of aerosolized pesticides. This paper-based device was able to detect the three classes of pesticides in aerosol phase with limits of detection equal to 30 ppb, 10 ppb, and 2 ppb, respectively for 2,4-D, glyphosate, and paraoxon.

We demonstrate the use of patterned aerosol adhesives to construct both planar and nonplanar 3D paper microfluidic devices. By spraying an aerosol adhesive through a metal stencil, the overall amount of adhesive used in assembling paper microfluidic devices can be significantly reduced. We show on a simple 4-layer planar paper microfluidic device that the optimal adhesive application technique and device construction style depends heavily on desired performance characteristics. By moderately increasing the overall area of a device, it is possible to dramatically decrease the wicking time and increase device success rates while also reducing the amount of adhesive required to keep the device together. Such adhesive application also causes the adhesive to form semi-permanent bonds instead of permanent bonds between paper layers, enabling single-use devices to be non-destructively disassembled after use. Nonplanar 3D origami devices also benefit from the semi-permanent bonds during folding, as it reduces the likelihood that unrelated faces may accidently stick together. Like planar devices, nonplanar structures see reduced wicking times with patterned adhesive application vs uniformly applied adhesive.

A microfluidic paper-based analytical device (μPAD) fabricated by wax printing was designed to assess occupational exposure to metal-containing aerosols. This method employs rapid digestion of particulate metals using microliters of acid added directly to a punch taken from an air sampling filter. Punches were then placed on a μPAD, and digested metals were transported to detection reservoirs upon addition of water. These reservoirs contained reagents for colorimetric detection of Fe, Cu, and Ni. Dried buffer components were used to set the optimal pH in each detection reservoir, while precomplexation agents were deposited in the channels between the sample and detection zones to minimize interferences from competing metals. Metal concentrations were quantified from color intensity images using a scanner in conjunction with image processing software. Reproducible, log-linear calibration curves were generated for each metal, with method detection limits ranging from 1.0 to 1.5 μg for each metal (i.e., total mass present on the μPAD). Finally, a standard incineration ash sample was aerosolized, collected on filters, and analyzed for the three metals of interest. Analysis of this collected aerosol sample using a μPAD showed good correlation with known amounts of the metals present in the sample. This technology can provide rapid assessment of particulate metal concentrations at or below current regulatory limits and at dramatically reduced cost.

This White Paper presents the Consensus Statements derived from a Special Issues Board (SIB) held in Chicago, IL, in October 2010. The SIB was convened to address the question of whether there is a need for both aerosol and aqueous intranasal steroids (INSs) in the treatment of allergic rhinitis (AR). The faculty reviewed the published record of efficacy and safety of aerosol and aqueous INSs, as well as patient and physician satisfaction and preferences for currently available INSs, and burden of disease. Agreement on unmet needs also included the practice experience of the faculty and their colleagues. The body of evidence indicates that INSs are equally effective and well tolerated for most patients. However, differences exist among current aqueous formulations as well as between these products and their aerosol antecedents, based on the properties of the nasal spray. Aerosol formulations, although no longer available, may be preferred for some patients with specific pathophysiology and may be preferred by some patients based on sensory perception. There are good reasons to expand the currently available options of INSs by having both aerosol and aqueous formulations.

One limitation in the growing field of ambient or direct analysis methods is reduced selectivity caused by the elimination of chromatographic separations prior to mass spectrometric analysis. We explored the use of high-field asymmetric waveform ion mobility spectrometry (FAIMS), an ambient pressure ion mobility technique, to separate the closely related opiate isomers of morphine, hydromorphone, and norcodeine. These isomers cannot be distinguished by tandem mass spectrometry. Separation prior to MS analysis is, therefore, required to distinguish these compounds, which are important in clinical chemistry and toxicology. FAIMS was coupled to a triple quadrupole mass spectrometer, and ionization was performed using either a pneumatically assisted heated electrospray ionization source (H-ESI) or paper spray, a direct analysis method that has been applied to the direct analysis of dried blood spots and other complex samples. We found that FAIMS was capable of separating the three opiate structural isomers using both H-ESI and paper spray as the ionization source.

Radon gas was allowed to accumulate in its radium source and then injected into a 36 m(3) test room, resulting in an initial radon concentration of 15 kBq m(-3). Filter papers were used to collect the short-lived radon progeny and thus to measure the Potential Alpha Energy Concentration (PAEC) in-situ in the year 1984 at different times and conditions according to the experimental design. The radon progeny collected on the filter papers were studied as a function of aerosol particle concentration ranging from 10(2)-10(5) particles cm(-3) in three different experiments. The highest aerosol particle concentration was generated by indoor cigarette smoking. Those filters were stored after the experiment, and were used after 16 years to study the activity of the radon long-lived alpha emitter progeny, (210)Po (T(1/2)=138 days). This isotope is separated from the short-lived progeny by (210)Pb beta emitter with 22.3 years half-life. After 16 years' storage of these filters, each filter paper was sandwiched and wrapped between two CR-39 nuclear track detectors, to put the detectors in contact with the surfaces of different filters, for 337 days. Correlation between the PAEC measured using filter papers in the year 1984 and the activity of long-lived alpha emitter (210)Po on the same filter papers measured in the year 2000 were studied. The results of the (210)Po activity showed a very good correlation of 0.92 with the PAEC 16 years ago. The results also depict that the PAEC and (210)Po activity in indoor air increased with the increase of aerosol particle concentration, which shows the attachment of short-lived radon progeny with the aerosol particles. The experiment proves that indoor cigarette smoking is a major source of aerosol particles carrying radon progeny and, thus, indoor cigarette smoking is an additional source of internal radiation hazard to the occupants whether smoker or non-smoker.

Previous studies of paper machine operators have to a large extent focused on endotoxins as a possible health hazard, but not culturable micro-organisms (MOs).Based on exposure assessment in 11 paper mills workers exposed to culturable bio-aerosols were grouped in three exposure groups. 781 exposed and 285 unexposed workers completed a questionnaire that provided data pertaining to infections and associated symptoms.Concentrations of culturable bacteria in process waters varied in the range 10(4)-10(6) colony forming units (cfu)/ml, and in bio-aerosols concentrations varied typically in the range 10(4)--10(5) cfu/m3. Operators exposed to bio-aerosols reported higher cumulative incidence of symptoms associated with infections compared to the reference population (ORs = 1.7-5.9), and the group of highest exposed workers reported higher cumulative incidence than the group of lowest exposed (ORs = 1.2-3.6).Exposure to bio-aerosols containing culturable MOs may induce symptoms associated with infections among operators in paper mills.

It is essential to understand the data quality of 10+ year OMI ozone product and impacts of the “Row Anomaly (RA)”. We validate the OMI ozone-profile (PROFOZ) product from Oct. 2004 to Dec. 2014 against ozonesonde observations globally. Generally, OMI has good agreement with ozonesondes. The spatiotemporal variation of retrieval performance suggests the need to improve OMI’s radiometric calibration especially during the post-RA period to maintain the long-term stability.

Airborne particulate matter (PM) pollution significantly impacts human health, but the cellular mechanisms of PM-induced toxicity remain poorly understood. A leading hypothesis on the effects of inhaled PM involves the generation of cellular oxidative stress. To investigate PM-induced oxidative stress, analytical methods have been developed to study the chemical oxidation of dithiothreitol (DTT) in the presence of PM. Although DTT readily reacts with several forms of reactive oxygen species, this molecule is not endogenously produced in biological systems. Glutathione (GSH), on the other hand, is an endogenous antioxidant that is produced throughout the body and is directly involved in combating oxidative stress in the lungs and other tissues. We report here a new method for measuring aerosol oxidative activity that uses silver nanoparticle (AgNP) aggregation coupled to glutathione (GSH) oxidation in a paper-based analytical device. In this assay, the residual reduced GSH from the oxidation of reduced GSH to its disulfide induces the aggregation of AgNPs on a paper-based analytical device, which produces a reddish-brown product. Two methods for aerosol oxidative reactivity are presented: one based on change in color intensity using a traditional paper-based techniques and one based on the length of the color product formed using a distance-based device. These methods were validated against traditional spectroscopic assays for DTT and GSH that employ Elman's reagent. No significant difference was found between the levels measured by all three GSH methods (our two paper-based devices and the traditional method) at the 95% confidence level. PM reactivity towards GSH was less than towards DTT most likely due to the difference in the oxidation potential between the two molecules.

During five campaigns at sea and 11 on land in 2001–2007, aerosols were measured in the coastal zone and over the open sea in the Gdansk Basin (southern Baltic). Sea salt concentrations were high both over Gdynia (2.0–12.2 μ g m − 3 ) and at sea (1.3–14.5 μ g m − 3 ). The intensity of the generation and transport of marine aerosols increased exponentially with wind speeds > 5 m s − 1 over land and > 3 m s − 1 over the Gulf of Gdansk, this being most noticeable with Baltic and oceanic advection. Sea breezes were conducive to the transport of marine aerosols over land areas. The sea was also the origin of both sea salt and non-sea salt sulphate aerosols. An interesting increase in the proportion of non-sea salt-related sulphates (86.7%) was observed in spring, when the biological processes in the sea were more intense.

Taste of a pharmaceutical formulation is an important parameter for the effectiveness of pharmacotherapy. Cetirizine dihydrochloride (CET) is a second-generation antihistamine that is commonly administered in allergy treatment. CET is characterized by extremely bitter taste and it is a great challenge to successfully mask its taste; therefore the goal of this work was to formulate and characterize the microparticles obtained by the spray drying method with CET and poly(butyl methacrylate-co-(2-dimethylaminoethyl) methacrylate-co-methyl methacrylate 1:2:1 copolymer (Eudragit E PO) as a barrier coating. Assessment of taste masking by the electronic tongue has revealed that designed formulations created an effective taste masking barrier. Taste masking effect was also confirmed by the in vivo model and the in vitro release profile of CET. Obtained data have shown that microparticles with a drug/polymer ratio (0.5:1) are promising CET carriers with efficient taste masking potential and might be further used in designing orodispersible dosage forms with CET.

Brewer spectrophotometers are widely used instruments which perform spectral measurements of the direct, the scattered and the global solar UV irradiance. By processing these measurements a variety of secondary products can be derived such as the total columns of ozone (TOC), sulfur dioxide and nitrogen dioxide and aerosol optical properties. Estimating and limiting the uncertainties of the final products is of critical importance. High-quality data have a lot of applications and can provide accurate estimations of trends.

More than 2 years of columnar atmospheric aerosol measurements (2006–2009) at the Tamanrasset site (22.79° N, 5.53° E, 1377 m a.s.l.), in the heart of the Sahara, are analysed. Aerosol Robotic Network (AERONET) level 2.0 data were used. The KCICLO (K is the name of a constant and ciclo means cycle in Spanish) method was applied to a part of the level 1.5 data series to improve the quality of the results. The annual variability of aerosol optical depth (AOD) and Ångström exponent (AE) has been found to be strongly linked to the convective boundary layer (CBL) thermodynamic features. The dry-cool season (autumn and winter) is characterized by a shallow CBL and very low mean turbidity (AOD ~ 0.09 at 440 nm, AE ~ 0.62). The wet-hot season (spring and summer) is dominated by high turbidity of coarse dust particles (AE ~ 0.28, AOD ~ 0.39 at 440 nm) and a deep CBL. The aerosol-type characterization shows desert mineral dust as the prevailing aerosol. Both pure Saharan dust and very clear sky conditions are observed depending on the season. However, several case studies indicate an anthropogenic fine mode contribution from the industrial areas in Libya and Algeria. The concentration weighted trajectory (CWT) source apportionment method was used to identify potential sources of air masses arriving at Tamanrasset at several heights for each season. Microphysical and optical properties and precipitable water vapour were also investigated. The AERONET sun photometer at Tamanrasset has been calibrated within AERONET-EUROPE TNA supported by the PHOTONS and RIMA networks and partially financed by the European Community – Research Infrastructure Action under the Seventh Framework Programme (FP7/2007-2013) “Capacities” specific programme for Integrating Activities, ACTRIS grant agreement no. 262254. Financial support from the Spanish MINECO (projects CGL2011-23413, CGL2012-33576 and CGL2012-37505) is also gratefully acknowledged. J. M. Baldasano and S. Basart acknowledge the Supercomputación y eCiencia project (CSD2007-0050) from the Consolider-Ingenio 2010 and Severo Ochoa (SEV-2011-00067) programs of the Spanish Government.

A sensitivity study of aerosol retrievals to the geometrical configuration of the ground-based sky radiometer observations is carried out through inversion tests. Specifically, this study is focused on principal plane and almucantar observations, since these geometries are employed in AERONET (AErosol RObotic NETwork). The following effects have been analyzed with simulated data for both geometries: sensitivity of the retrieval to variability of the observed scattering angle range, uncertainties in the assumptions of the aerosol vertical distribution, surface reflectance, possible instrument pointing errors, and the effects of the finite field of view. Financial support was provided by the Spanish CICYT (CGL2009-09740 and CGL2011-23413, CGL2011-13085-E). The research leading to these results was supported by funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 262254 [ACTRIS]. We also thank the Environmental Council of the CyL Regional Government (Consejería de Medio Ambiente, Junta de Castilla y León) for supporting this research.

The shortwave radiative forcing (1F) and the radiative forcing efficiency (1Feff) of natural and anthropogenic aerosols have been analyzed using estimates of radiation both at the Top (TOA) and at the Bottom Of Atmosphere (BOA) modeled based on AERONET aerosol retrievals. Six main types of atmospheric aerosols have been compared (desert mineral dust, biomass burning, urbanindustrial, continental background, oceanic and free troposphere) in similar observational conditions (i.e., for solar zenith angles between 55 and 65 ) in order to compare the nearly same solar geometry. We acknowledge to the MEC (Ministry of Education and Science, Spain) for the next supports: projects CGL2007-66477-C02-02/CLI, CGL2008-04740/CLI and CGL2010-21366-C04-01.

The incidence of microbes in the nasal cavities of workers in three paper and board mills was investigated. A total of 234 persons exposed to microbial aerosols and splashes from paper machine wires and debarker drums formed the exposed group. The control group consisted of 294 workers from the dry working areas: the winding and packing sections. Chi-square analysis was used to test the differences in the frequency of microbial incidence and various symptoms between the exposed and control groups. The nasal cavities of many workers, particularly workers in the debarkers, proved to be contaminated by Klebsiella pneumoniae, other coliforms, yeasts, and molds; usually only one microbe was involved, but sometimes two or several species were found. Nasal bacteria and yeasts were largely derived from the mill and debarker air; the microbes in the air came mainly from process waters. Lack of association of nasopharyngeal symptoms with either exposure to aerosols or nasal microbial contamination was interpreted as an indication of host defenses that were adequate to protect workers from harmful microbial colonization in paper mill environments.

The widespread use of inhaled corticosteroids (ICS) since the early 1970's has meant that asthma is generally better controlled in comparison with previous decades. Nevertheless, recent patient interview surveys indicate that there is still a lot to gain in terms of abolishing daytime and nocturnal symptoms, and asthma exacerbations. It is important to use the terms asthma 'control' and asthma 'severity' in a correct way. Whereas asthma control reflects fluctuation in symptoms and lung function (or lack of them) over time, asthma severity reflects both asthma control and the need for medication. Thus, 'severity' is a property of the disease which reflects the degree of pathophysiological abnormality, whereas 'control' refers to the reduction of the clinical manifestations of disease achieved by treatment - thereby reflecting the adequacy of treatment. This introductory review, the first of a series of review papers to be published in this journal by the ADMIT team (see Appendix), discusses briefly our present knowledge of asthma control, its components, factors that may limit patients' ability to achieve optimal asthma control, and instruments to measure asthma control.

The collection efficiency of Whatman 41 filter paper has been determined using submicron test aerosols of monodispersed polystyrene latex. Measurements were made over a velocity range of 12 to 195 fpm, using aerosols with diameters of 0.088, 0.188, 0.264, 0.365, and 0.557 mu . For sizes less than 0.557 mu , well-developed efficiency minima occur in the velocity range of 20 to 30 fpm. In no case was the efficiency found to be below 70%. At 195 fpm, the efficiency was essentially size-independent. (auth)

The penetration of particles through IPC 1478, Whatman 41, and Type 5G filter papers has been measured by using monodispersed polystyrene latex aerosols at ambient temperature and pressure. The aerosols were 0.264, 0.365, 0.557, 0.796, and 1.099 microns in diameter and consisted of more than 85% single particles. Initial electronic charge on the test aerosols was reduced with a radiation source to an average elemental electronic charge per particle of 0 to 3. Penetration was measured through filters at air velocities from 0.1 to 100 cm/sec. Well-defined velocities for maximum penetration for each particle size were found for the three filter papers. Particle sizes for maximum penetration were also found for IPC 1478 and Type 5G papers as a function of air velocity.

IPC-1478 filter paper efficiency was evaluated using polystyrene latex and dioctyl phthalate (DOP aerosols). Efficiency was measured as a function of particle size, filtration velocity, and filter mass loading. Experimental results of 0.557-µm and larger particle sizes indicate that this medium has limited effectiveness under high-velocity and high-loading conditions. Differences in efficiency were observed when this medium was tested with solid and liquid aerosols.

Purpose Chloroquine and hydroxychloroquine are effective against respiratory viruses in vitro. However, they lack antiviral efficacy upon oral administration. Translation of in vitro to in vivo exposure is necessary for understanding the disconnect between the two to develop effective therapeutic strategies. Methods We employed an in vitro ion-trapping kinetic model to predict the changes in the cytosolic and lysosomal concentrations of chloroquine and hydroxychloroquine in cell lines and primary human airway cultures. A physiologically based pharmacokinetic model with detailed respiratory physiology was used to predict regional airway exposure and optimize dosing regimens. Results At their reported in vitro effective concentrations in cell lines, chloroquine and hydroxychloroquine cause a significant increase in their cytosolic and lysosomal concentrations by altering the lysosomal pH. Higher concentrations of the compounds are required to achieve similar levels of cytosolic and lysosomal changes in primary human airway cells in vitro. The predicted cellular and lysosomal concentrations in the respiratory tract for in vivo oral doses are lower than the in vitro effective levels. Pulmonary administration of aerosolized chloroquine or hydroxychloroquine is predicted to achieve high bound in vitro-effective concentrations in the respiratory tract, with low systemic exposure. Achieving effective cytosolic concentrations for activating immunomodulatory effects and adequate lysosomal levels for inhibiting viral replication could be key drivers for treating viral respiratory infections. Conclusion Our analysis provides a framework for extrapolating in vitro effective concentrations of chloroquine and hydroxychloroquine to in vivo dosing regimens for treating viral respiratory infections. Graphical abstract

Effective hand drying is an important part of hand hygiene that can reduce the risk of infectious disease transmission through cross-contamination of surfaces by wet hands. However, hand drying methods may also cause aerosolisation of pathogenic microorganisms if they are present in washed hands. This study investigated experimentally the impact of washing hands and different hand drying methods on the concentration and size distribution of aerosols and bacteria in indoor air. In this experiment, aerosol and bacteria concentrations were measured in indoor air while volunteers rinsed their hands with water or washed with soap and water prior to drying them with paper towels or jet air dryers. Results showed that the concentration of aerosols and bacteria in air increased with people walking in the room and washing hands, with a further increase during the hand drying process. The concentration of aerosols decreased with particle size, with maximum concentrations after drying hands of 6.63 × 106 ± 6.49 × 105 and 2.28 × 104 ± 9.72 × 103 particles m−3 for sizes 0.3 to 2 ± 1.48 × 102 CFU m−3 (jet air dryers) and 4.50 × 102 ± 4.35 × 101 CFU m−3 (paper towels). This study indicates that the increase of aerosols and bacteria in air after drying hands with jet air dryers or paper towels are comparable and not statistically different from concentrations associated with walking and washing hands in the same environment. This work can support the development of hand hygiene practices and guidelines for public washrooms.

Motivation With the coronavirus pandemic still raging, prophylactic-nasal and early-treatment throat-sprays could help prevent infection and reduce viral load. Niclosamide has the potential to treat a broad-range of viral infections if local bioavailability is optimized as mucin-penetrating solutions that can reach the underlying epithelial cells. Experimental pH-dependence of supernatant concentrations and dissolution rates of niclosamide were measured in buffered solutions by UV/Vis-spectroscopy for niclosamide from different suppliers (AK Sci and Sigma), as precipitated material, and as cosolvates. Data was compared to predictions from Henderson-Hasselbalch and precipitation-pH models. Optical-microscopy was used to observe the morphologies of original, converted and precipitated niclosamide. Results Niclosamide from the two suppliers had different polymorphs resulting in different dissolution behavior. Supernatant concentrations of the “AKSci-polymorph” increased with increasing pH, from 2.53μM at pH 3.66 to 300μM at pH 9.2, reaching 703μM at pH 9.63. However, the “Sigma-polymorph” equilibrated to much lower final supernatant concentrations, reflective of more stable polymorphs at each pH. Similarly, when precipitated from supersaturated solution, or as cosolvates, niclosamide also equilibrated to lower final supernatant concentrations. Polymorph equilibration though was avoided by using a solvent-exchange technique to make the solutions. Conclusions Given niclosamide’s activity as a host cell modulator, optimized niclosamide solutions could represent universal prophylactic nasal and early treatment throat sprays against COVID19, its more contagious variants, and other respiratory viral infections. They are the simplest and potentially most effective formulations from both an efficacy standpoint as well as manufacturing and distribution, (no cold chain). They now just need testing. Supplementary Information The online version contains supplementary material available at 10.1007/s11095-021-03112-x.

Summary Background Dental aerosol-generating procedures (AGPs) have been associated with risk for transmitting infectious agents. However, existing infection control monitoring studies potentially underestimate the extent of contamination, due to methodological inadequacies. These studies employed settle plate methodology which only captures droplets that land on agar plates, but not those suspended in air. Furthermore, bacterial culture was used to determine the extent of contamination, without accounting for non-bacterial sources of contamination. Aims This study sought to bridge these gaps by establishing a monitoring protocol involving active aerosol sampling and analysis of two dental AGPs, root canal treatment (RCT) and scaling. Methods RCT and scaling were performed with standard aerosol mitigation precautions. Aerosols generated throughout each procedure were sampled using the air sampler device, while contamination of operatory fomites and personal protective equipment was sampled using surface swabs, before and post-treatment. The amount of contamination was quantified using bacterial culture and adenosine triphosphate (ATP) assay. Findings RCT generated insignificant aerosol and splatter, supporting the infection control procedures' effectiveness. Conversely, scaling significantly increased the amount of aerosol and splatter. When comparing bacterial culture and ATP assay, the magnitude of contamination obtained with ATP assay was greater, suggesting that ATP assay may have detected additional contamination of human origin and bacteria that was not recovered by the culture conditions employed. Conclusions This monitoring protocol is feasible in the dental setting and determines the extent of contamination generated during AGPs. This could be adopted in future studies to overcome the limitations of the existing literature.

This article reviews the information on the climatic effect of carbon dioxide and aerosols and outlines man's part in contributing to their occurence. Recent downward trends in the average surface temperature of the biosphere has lead some scientists to conclude that albedo increases due to the effect of aerosol backscatter is the causative mechanism. While there is evidence for and against this hypothesis, this paper emphasizes that albedo changes due to aerosol modification of cloud cover may be a more significant mechanism for explaining temperature trends.

Evidence suggests that Coxiella burnetii, which is shed in the milk, urine, feces, and birth products of infected domestic ruminants, can lead to Q fever disease following consumption of unpasteurized dairy products; however, C. burnetii is not believed to be a major gastrointestinal pathogen. Most infections are associated with inhalation of aerosols generated from the excreta of domestic ruminants. We recently demonstrated that C. burnetii delivered by oral gavage (OG) resulted in dissemination and an immune response; however, it is unclear how infection via the oral route compares to other well-established routes. Therefore, we delivered three strains of C. burnetii (representing three pertinent sequence types in the United States, such as ST16, ST20, and ST8) to immunocompetent mice in four doses via aerosol challenge (AC), intraperitoneal injection (IP), or OG. Low dose (10^5) of ST16 by OG was insufficient to cause infection, yet doses 1,000- or 100-fold lower by IP or AC, respectively, induced a robust immune response and dissemination. Despite being able to induce an immune response in a dose-dependent manner, administration of C. burnetii via OG is the least efficient route tested. Not only were the immune responses and bacterial loads diminished in mice exposed by OG relative to AC or IP, the efficiency of transmission was also inferior. High doses (10^8) were not sufficient to ensure transmission to 100% of the ST20 or ST8 cohorts. These results may provide some basis for why ingestion of C. burnetii as a mode of Q fever transmission is not often reported.

We report the observation of photoluminescence emission from airborne gold, silver, and copper nanoparticles. A continuous wave 532 nm laser was employed for excitation. Photoluminescence from gold nanoparticles carried in a nitrogen gas flow was both spectrally resolved and directly imaged in situ using an intensified charge-coupled device camera. The simultaneously detected Raman signal from the nitrogen molecules enables quantitative estimation of the photoluminescence quantum yield of the gold nanoparticles. Photoluminescence from metal nanoparticles carried in a gas flow provides a potential tool for operando imaging of plasmonic metal nanoparticles in aerosol reactions., Graphical Abstract

Anaerobic digestion is an emerging technology producing energy from renewable resources or food waste. Exposure screenings, comprising hazardous substances and biological agents, at different workplaces are necessary for a comprehensive overview of potential hazards in order to assess the risk of employees in biogas plants. In order to analyse these parameters, workplace measurements were conducted in seven full-scale anaerobic digesters. Personal and stationary sampling was performed for inhalable and respirable particles, volatile organic compounds, ammonia, hydrogen sulphide, carbon monoxide, and carbon dioxide. Furthermore, concentrations of the total cell count, endotoxins, and fungi—down to species level—were determined in comparison to windward air. Sequencing of the 16S rRNA genes was utilized for the determination of the bacterial composition inside the biogas plants. Measurements of hazardous substances show hardly values reaching the specific occupational exposure limit value, except ammonia. An approximate 5-fold increase in the median of the total cell count, 15-fold in endotoxins, and 4-fold in fungi was monitored in the biogas plants compared with windward air. Specifying the comparison to selected workplaces showed the highest concentrations of these parameters for workplaces related to delivery and cleaning. Strikingly, the fungal composition drastically changed between windward air and burdened workplaces with an increase of Aspergillus species up to 250-fold and Penicillium species up to 400-fold. Sequence analyses of 16S rRNA genes revealed that many workplaces are dominated by the order of Bacillales or Lactobacillales, but many sequences were not assignable to known bacteria. Although significant changes inside the biogas plant compared with windward air were identified, that increase does not suggest stricter occupational safety measures at least when applying German policies. However, exposure to biological agents revealed wide ranges and specific workplace measurements should be conducted for risk assessment.

Coronavirus and its spread all over the world have been the most challenging crisis in 2020. Hospitals are categorized among the most vulnerable centers due to their presumably highest traffic of this virus. In this study, centrifugal isolation of coronavirus is successfully deployed for purifying hospitals’ air using air conditioners and ducts, suggesting an efficient setup. Numerical simulations have been used to testify the proposed setup due to the complexities of using experimental investigation such as high cost and clinical hazards of the airborne SARS-CoV-2 in the air. Results show that a 20-cm pipe with an inlet velocity of 4 m/s constitutes the best choice for the separation and purification of air from the virus. The proposed scalable method also efficiently separates larger particles, but it can separate smaller particles too. Numerical results also suggest installing the air purifying system on the floor of the hospitals’ room for maximum efficiency.

Thermal caves represent an environment characterized by unique chemical/physical properties, often used for treatment and care of musculoskeletal, respiratory, and skin diseases. However, these environments are poorly characterized for their physical and microbiological characteristics; furthermore, the recent pandemic caused by COVID-19 has highlighted the need to investigate the potential transmission scenario of SARS-CoV-2 virus in indoor environments where an in-depth analysis of the aerosol concentrations and dimensional distributions are essential to monitor the spread of the virus. This research work was carried out inside a natural cave located in Viterbo (Terme dei Papi, Italy) where a waterfall of sulfur–sulfate–bicarbonate–alkaline earth mineral thermal water creates a warm-humid environment with 100% humidity and 48 °C temperature. Characterization of the aerosol and bioaerosol was carried out to estimate the personal exposure to aerosol concentrations, as well as particle size distributions, and to give an indication of the native microbial load. The data obtained showed a predominance of particles with a diameter greater than 8 µm, associated with low ability of penetration in the human respiratory system. A low microbial load was also observed, with a prevalence of noncultivable strains generated by the aerosolization of the thermal waters. Finally, the estimation of SARS-CoV-2 infection risk by means of mathematical modeling revealed a low risk of transmission, with a decisive effect given by the mechanical ventilation system, which together with the adoption of social distancing measures makes the risk of infection extremely low. Supplementary information The online version contains supplementary material available at (10.1007/s10653-021-00870-w)

The composition and distribution of airborne particles in different locations in a salt mine were determined in terms of their origin, the distance from the air inlet, and the adaptation of post-mining chambers and corridors for tourists and general audience. The composition of aerosols in air was also evaluated from the perspective of human health. Air samples were collected on filters by using portable air pumps, in a historical underground salt mine in Bochnia (Poland), which is currently a touristic and recreation attraction and sanatorium. The particulate matter (PM) concentration was determined using the gravimetric method by weighing quartz filters. The content of carbon, water-soluble constituents, trace elements, and minerals was also determined. A genetic classification of the suspended matter was proposed and comprised three groups: geogenic (fragments of rock salt and associated minerals from the deposit), anthropogenic (carbon-bearing particles from tourist traffic and small amounts of fly ash, soot, and rust), and biogenic particles (occasional pollen). The total PM concentration in air varied between 21 and 79 μg/m3 (with PM4 constituting 4–24 μg/m3). The amount of atmospheric dust components coming from the surface was low and decreased with the distance from the intake shaft, thus indicating the self-cleaning process. NaCl dominated the water-soluble constituents, while Fe, Al, Ag, Mn, and Zn dominated the trace elements, with the concentration of majority of them below 30 ng/m3. These metals are released into air from both natural sources and the wear or/and corrosion of mining and tourists facilities in the underground functional space. No potentially toxic elements or constituents were detected. The presence of salt particles and salty spray in the atmosphere of salt mine, which may have anti-inflammatory and antiallergic properties, is beneficial to human health. This study will allow for a broader look at the potential of halotherapy in underground salt mines from a medical and regulatory point of view.

Background Fluid Resistant Surgical Masks have been implemented in UK personal protective equipment (PPE) guidelines for COVID-19 for all care sites that do not include aerosol-generating procedures (AGPs). FFP3 masks are used in AGP areas. Concerns from the ENT and plastic surgery communities out with intensive care units have questioned this policy. Emerging evidence on cough clouds and health care worker deaths has suggested that a review is required. Aims To test the efficacy of Fluid Resistant Surgical Mask with and without adaptions for respiratory protection. To test the efficacy of FFP and FFP3 regarding fit testing and usage. Methods A smoke chamber test of 5 min to model an 8-h working shift of exposure while wearing UK guideline PPE using an inspiratory breathing mouthpiece under the mask. Photographic data were used for comparison. Results The Fluid Resistant Surgical Mask gave no protection to inhaled smoke particles. Modifications with tape and three mask layers gave slight benefit but were not considered practical. FFP3 gave complete protection to inhaled smoke but strap tension needs to be ‘just right’ to prevent facial trauma. Facial barrier creams are an infection risk. Conclusions Surgical masks give no protection to respirable particles. Emerging evidence on cough clouds and health care worker deaths suggests the implementation of a precautionary policy of FFP3 for all locations exposed to symptomatic or diagnosed COVID-19 patients. PPE fit testing and usage policy need to improve to include daily buddy checks for FFP3 users

Background:Critical shortages of personal protective equipment, especially N95 respirators, during the coronavirus disease 2019 (COVID-19) pandemic continues to be a source of concern. Novel methods of N95 filtering face-piece respirator decontamination that can be scaled-up for in-hospital use can help address this concern and keep healthcare workers (HCWs) safe.Methods:A multidisciplinary pragmatic study was conducted to evaluate the use of an ultrasonic room high-level disinfection system (HLDS) that generates aerosolized peracetic acid (PAA) and hydrogen peroxide for decontamination of large numbers of N95 respirators. A cycle duration that consistently achieved disinfection of N95 respirators (defined as ≥6 log10 reductions in bacteriophage MS2 and Geobacillus stearothermophilus spores inoculated onto respirators) was identified. The treated masks were assessed for changes to their hydrophobicity, material structure, strap elasticity, and filtration efficiency. PAA and hydrogen peroxide off-gassing from treated masks were also assessed.Results:The PAA room HLDS was effective for disinfection of bacteriophage MS2 and G. stearothermophilus spores on respirators in a 2,447 cubic-foot (69.6 cubic-meter) room with an aerosol deployment time of 16 minutes and a dwell time of 32 minutes. The total cycle time was 1 hour and 16 minutes. After 5 treatment cycles, no adverse effects were detected on filtration efficiency, structural integrity, or strap elasticity. There was no detectable off-gassing of PAA and hydrogen peroxide from the treated masks at 20 and 60 minutes after the disinfection cycle, respectively.Conclusion:The PAA room disinfection system provides a rapidly scalable solution for in-hospital decontamination of large numbers of N95 respirators during the COVID-19 pandemic.

Background The effectiveness of aerosol disinfection processes based on peracetic acid (PAA) might differ depending on the surface targeted. Especially antibacterial, oligodynamic materials have to be regarded as they could cause elevated decomposition of PAA. Aim This study aimed on the determination of differences in disinfection effectiveness using PAA caused by the treated material. Methods Aerosol disinfection of Geobacillus stearothermophilus spores was performed on the antibacterial, oligodynamic materials copper and brass in comparison to stainless steel and aluminium as well as polyvinylchloride, wood, and ceramics. Additionally, the influence of the materials on the decomposition reaction of PAA was evaluated. Results For aluminium and stainless steel as well as ceramics and polyvinylchloride, a disinfection of 106 spores of Geobacillus stearothermophilus on 40 cm² was obtained by the employment of 60 mL aerosolized disinfectant/m³ on laboratory scale (0.5 m³). For the application on the oligodynamic materials copper and brass an over 30% higher amount of disinfectant was necessary to achieve significant disinfection results, than for the other material surfaces. In contrast to aluminium and stainless steel, copper and brass caused elevated decomposition of PAA what seems to be the reason for the lowered disinfection effectiveness. Conclusions Applying aerosol disinfection processes, in addition to parameters such as room size and geometry, the treated materials have to be considered when determining the necessary amount of disinfectant.

Burkholderia mallei is a highly pathogenic bacterium that causes the fatal zoonosis glanders. The organism specifies multiple membrane proteins, which represent prime targets for the development of countermeasures given their location at the host-pathogen interface. We investigated one of these proteins, Pal, and discovered that it is involved in the ability of B. mallei to resist complement-mediated killing and replicate inside host cells in vitro, is expressed in vivo and induces antibodies during the course of infection, and contributes to virulence in a mouse model of aerosol infection. A mutant in the pal gene of the B. mallei wild-type strain ATCC 23344 was found to be especially attenuated, as BALB/c mice challenged with the equivalent of 5,350 LD50 completely cleared infection. Based on these findings, we tested the hypothesis that a vaccine containing the Pal protein elicits protective immunity against aerosol challenge. To achieve this, the pal gene was cloned in the vaccine vector Parainfluenza Virus 5 (PIV5) and mice immunized with the virus were infected with a lethal dose of B. mallei. These experiments revealed that a single dose of PIV5 expressing Pal provided 80% survival over a period of 40 days post-challenge. In contrast, only 10% of mice vaccinated with a PIV5 control virus construct survived infection. Taken together, our data establish that the Peptidoglycan-associated lipoprotein Pal is a critical virulence determinant of B. mallei and effective target for developing a glanders vaccine.

Face masks wearing during the coronavirus disease 2019 (COVID‐19) pandemic became ubiquitous. The aim of our study was to assess the use of face masks among young adults during the current viral pandemic. The survey was based on specially created Google Forms and posted on numerous Facebook groups for young people in Poland. Seven days were considered as a recall period. A total of 2315 answers were obtained, 2307 were finally analysis, as eight questionnaires were removed because of data incompleteness. 60.4% of responders declared using the face masks. Those who reported an atopic predisposition wore face masks significantly (P = .007) more commonly (65.5% and 57.7%, respectively). Cloth masks (46.2%) appeared to be most popular ones, followed by surgical masks (39.2%), respirators (N95 and FFP) (13.3%), half‐face elastomeric respirators (0.8%) and full‐face respirators (0.4%). Females significantly more frequently (P = .0001) used cloth masks; respirators, half‐face elastomeric respirators and full‐face respirators were used more commonly by males (P

Recently, total inward leakage (TIL) for filtering facepiece and elastomeric half-mask respirators (EHRs) was measured according to the International Organization for Standardization (ISO) test method standard 16900–1:2014 that showed larger TIL for corn oil aerosol than for NaCl aerosol. Comparison of TIL measured for different aerosols for higher protection level respirators is lacking. The objective of this study was to determine TIL for EHRs, full-facepiece respirators, and loose-fitting and tight-fitting powered air-purifying respirators (PAPRs) using NaCl and corn oil aerosols to compare. TIL was measured for two models each of EHRs, full-facepiece respirators, and loose-fitting and tight-fitting PAPRs. After fit testing with a PortaCount (TSI, St. Paul, MN) using the Occupational Safety and Health Administration (OSHA) protocol, eight subjects were tested in the NaCl aerosol chamber first and then in the corn oil aerosol chamber, while another eight subjects tested in the reverse order. Subjects were randomly assigned to one of the two groups. TIL was measured as a ratio of mass-based aerosol concentrations inside the mask to the test chamber while the subjects performed ISO 16900–1-defined exercises using continuous sampling methods. The concentration of corn oil aerosol was measured with one light scattering photometer, alternately, and NaCl aerosol was measured using two flame photometers. Results showed the geometric mean TIL for EHR was significantly (p < 0.05) larger for corn oil aerosol than for NaCl aerosol. EHR models equipped with P100 filters showed relatively smaller TIL values than the same models with N95 filters showing that TIL was inversely related to filter efficiency. Interestingly, TIL was significantly (p < 0.05) larger for NaCl aerosol than for corn oil aerosol for PAPRs, but not for full-facepiece respirators. TIL was inversely related to fit factors of respirator types. Overall, filter efficiency and faceseal leakage determine TIL. The relative trends in TIL for the two aerosols’ test methods differ between respirator types indicating that generalization of TIL for respirator types may not be appropriate when using different test agents.

Effective spatial disinfection systems are required for human health care, public hygiene, and food and medicine manufacturing. Although some aerosolized disinfectants were already applied to its purpose, accurate evaluation systems were under constructed. In this study, the spatial sporicidal activity of aerosolized hypochlorite solution (AHS) to dormant cells, Bacillus subtilis spores, was evaluated by an originally designed chamber system. In the test-chamber, AHS was supplied and existed as micro-droplets, and environmental relative humidity (RH) could be controlled. Available chlorine (AC) exposure was also controlled with appropriate AC loading but was influenced by the acidity of AHS. Our results indicated that inactivation of spore was depend on AC exposure amount and time. On the other hand, unsaturated environmental RH markedly decreased spore inactivation. This study indicated that our test-chamber system can provide reproducible test data under a homogeneous air condition, and, thereby, that the data obtained by the chamber system should contribute to predicting the AC-required dose to disinfect a whole building.

The inhibitory activities of grapefruit seed extract (GSE) on avian influenza virus (AIV), Newcastle disease virus (NDV), infectious bursal disease virus (IBDV), Salmonella Infantis (SI) and Escherichia coli (EC) were evaluated. Original GSE contained 0.24% benzalkonium chloride (BZC), however, 0.0025% BZC solution could not inactivate bacteria. The activity of diluted GSE (×100, ×500 and ×1,000 with redistilled water) against selected viruses and bacteria was evaluated in this study. The GSE solutions were incubated with the pathogens over a period of time after which the remaining viruses were titrated and the bacterial colonies were counted. In the presence of organic material-5% fetal bovine serum (FBS), the test solutions were sprayed at 1 cm and 30 cm distances to test the efficacy of GSE in a spray form. Furthermore, the efficacy of GSE against bacteria on clothes was tested using non-woven cloth. GSE×100 reduced the viral titer of both AIV and NDV even in 5% FBS condition. IBDV showed high resistance to GSE. GSE×1,000 inactivated both SI and EC within 5 sec, even in the presence of 5% FBS. The disinfectant was able to maintain its efficacy in the spray form at 30 cm distance. GSE was also effective against SI and EC inoculated on fabric. GSE is a potential novel disinfectant against viruses and bacteria, effective even within a short contact time.

The study relates to the use of automated plant protection systems in agriculture. The article presents a proprietary automated mobile platform with an aerosol generator of hot mist. Furthermore, the cause of the loss of a chemical preparation in the spraying of plant protection products on the tree crown was determined in the course of field research. A statistical analysis of the results of experiment was carried out and the effect of droplet size on leaf coating density was determined. The manuscript presents a diagram of the degree of penetration of the working solution as it drops into the crown of the tree, as well as a cross-sectional graph of the permeability of the spray from the projection of the fruit tree crown. The most effective modes of operation of the automated mobile platform for spraying plant protection products with a mist generator aggregate were established. Analysis of the results shows that the device meets the spraying requirements of the procedure for spraying plant protection products. The novelty of this research lies in the optimal modes identified by movement of the developed automated mobile platform and the parameters of plant treatment with protective equipment when using a hot mist generator. The following mode parameters were established: the speed of the automated platform was 3.4 km/h, the distance to the crown of the tree was 1.34 m, and the flow rate of the working fluid was 44.1 L/h. Average fuel consumption was 2.5 L/h. Effective aerosol penetration reduced the amount of working fluid used by up to 50 times.

Design Volumetric air flow was measured in a number of dental surgeries to calculate the air change rate per hour (ACHvent). In each surgery, measurements of aerosol removal by ventilation alone, and then with ventilation provided by a high-efficiency particulate air filter (PAC), were completed. The concentrations of aerosol particles of various sizes were recorded at baseline, after an initial period of incense burn, and then after 30 minutes of observation with and without the use of the PAC or ventilation system.Sample selection Ten dental surgeries with differing baseline ventilation rates had the concentrations of 0.3, 0.5 and 1.0 μm aerosol particles measured at 0 minutes, after 5 minutes of incense burn and then after 30 minutes of observation, firstly without the PAC system in operation and then with the PAC system in use.Data analysis For the 0.3 μm particles, velocities of aerosol removal were assessed by analysing the concentration decay constants with ventilation alone and ventilation with the PAC. Aerosol removal velocities were assessed by the time needed to reach 95% and 100% removal of accumulated aerosol particles.Results ACHvent in the ten different surgeries varied from 3-45. The concentration decay constants for the 0.3 μm particles with ventilation alone and ventilation with the PAC were correlated to the mechanical ventilation rate and combined respectively. For rooms with ACHvent of less than 15, accumulated aerosol particles could not be removed by ventilation alone in 30 minutes. The PAC accelerated aerosol removal and reduced aerosol accumulation, and with the use of the PAC in addition to ventilation, accumulated aerosols were removed completely in 4-12 minutes. The PAC was shown to be more beneficial in rooms with poor ventilation and the added effectiveness of the PAC in aerosol removal was inversely correlated with the ACHvent by ventilation.Conclusions Although the air change rate differed considerably among dental surgeries, this study suggests that the addition of the PAC with a HEPA filter significantly increased aerosol removal and lessened aerosol accumulation, particularly in rooms with low ventilation rates.