An insight into recent PM aerosol light scattering properties and particle number concentration variabilities at the suburban site ATOLL in Northern France.

Aerosol particles in the PM fraction considerably influence the climate-related effects of aerosols and impact human health despite representing very variable fractions of the total aerosol mass concentration. Aerosol optical measurement techniques (aerosol light scattering) may not be sufficiently effective for detecting all particles in the PM fraction, particularly regarding number concentration. The present study investigates temporal variations of aerosol light scattering properties and particle number concentration (PNC) at different size modes in the PM fraction at the atmospheric site ATOLL (The Atmospheric Observations in Lille), Northern France from January 2018 to February 2023.

Are there Risks from Nanocomposite Restoration Grinding for Dentists?

Objectives: To evaluate the effect of short-term inhalational exposure to nanoparticles released during dental composite grinding on oxidative stress and antioxidant capacity markers.

Materials And Methods: Twenty-four healthy volunteers were examined before and after exposure in dental workshop. They spent 76.

Transcriptome changes in humans acutely exposed to nanoparticles during grinding of dental nanocomposites.

Today, there is a lack of research studies concerning human acute exposure to nanoparticles (NPs). Our investigation aimed to simulate real-world acute inhalation exposure to NPs released during work with dental nanocomposites in a dental office or technician laboratory. Blood samples from female volunteers were processed before and after inhalation exposure.

Genetic alteration profiling in middle-aged women acutely exposed during the mechanical processing of dental nanocomposites.

Nanoparticles (NPs) have become an important part of everyday life, including their application in dentistry. Aside from their undoubted benefits, questions regarding their risk to human health, and/or genome have arisen. However, studies concerning cytogenetic effects are completely absent.

Elevated glutathione in researchers exposed to engineered nanoparticles due to potential adaptation to oxidative stress.

To find a practical biomonitoring method for researchers exposed to nanoparticles causing oxidative stress. In a continuation of a study in 2016-2018, biological samples (plasma, urine and exhaled breath condensate [EBC]) were collected in 2019-2020 from 43 researchers (13.8 ± 3.

Positive matrix factorization of seasonally resolved organic aerosol at three different central European background sites based on nuclear magnetic resonance Aerosolomics data.

Concentration data derived from H NMR analysis of the water-soluble organic compounds from fine aerosol (PM) at three Central European background stations, Košetice, Frýdlant (both in the Czech Republic), and Melpitz (Germany), were used for detailed source apportionment analysis. Two winter and two summer episodes (year 2021) with higher organic concentrations and similar wind directions were selected for NMR analyses. The concentration profiles of 61 water-soluble organic compounds were determined by NMR Aerosolomics and a principal component analysis (PCA) was performed on this dataset.

A year-round observation of δC of dicarboxylic acids and related compounds in fine aerosols: Implications from Central European background site.

Isotopic analysis of specific compounds in aerosols can be a useful tool when studying atmospheric processes. Here, we present the results of stable carbon isotope ratio (δC) measurements performed on a one-year set (n = 96, Sep. 2013-Aug.

Different approaches to explore the impact of COVID-19 lockdowns on carbonaceous aerosols at a European rural background site.

To prevent the fast spread of COVID-19, worldwide restrictions have been put in place, leading to a reduction in emissions from most anthropogenic sources. In this study, the impact of COVID-19 lockdowns on elemental (EC) and organic (OC) carbon was explored at a European rural background site combining different approaches: - "Horizontal approach (HA)" consists of comparing concentrations of pollutants measured at 4 m a.g.

High-quality and easy-to-regenerate personal filter.

Proper respiratory tract protection is the key factor to limiting the rate of COVID-19 spread and providing a safe environment for health care workers. Traditional N95 (FFP2) respirators are not easy to regenerate and thus create certain financial and ecological burdens; moreover, their quality may vary significantly. A solution that would overcome these disadvantages is desirable.

Hygroscopic growth and CCN activity of secondary organic aerosol produced from dark ozonolysis of γ-terpinene.

The hygroscopic growth factor (GF) and cloud condensation nuclei (CCN) activity of secondary organic aerosol (SOA) particles produced during dark ozonolysis of γ-terpinene under different reaction conditions were investigated. The SOA particles were produced in the presence or absence of cyclohexane, an OH scavenger; 1,3,5-trimethylbenzene, an anthropogenic volatile organic compound; and (NH)SO seed particles. A hygroscopicity tandem differential mobility analyzer was used to determine the GFs of the SOA particles at RHs ≤ 93%.

Seasonal changes in stable carbon isotopic composition in the bulk aerosol and gas phases at a suburban site in Prague.

Isotope fractionation between the gas and aerosol phases is an important phenomenon for studying atmospheric processes. Here, for the first time, seasonally resolved stable carbon isotope ratio (δC) values are systematically used to study phase interactions in bulk aerosol and gaseous carbonaceous samples. Seasonal variations in the δC of total carbon (TC; δC) and water-soluble organic carbon (WSOC; δC) in fine aerosol particles (PM) as well as in the total carbon of part of the gas phase (TCgas; δC) were studied at a suburban site in Prague, Czech Republic, Central Europe.

Individual DNA Methylation Pattern Shifts in Nanoparticles-Exposed Workers Analyzed in Four Consecutive Years.

A DNA methylation pattern represents an original plan of the function settings of individual cells and tissues. The basic strategies of its development and changes during the human lifetime are known, but the details related to its modification over the years on an individual basis have not yet been studied. Moreover, current evidence shows that environmental exposure could generate changes in DNA methylation settings and, subsequently, the function of genes.

Commonly available but highly effective protection against SARS-CoV-2 during gastrointestinal endoscopies.

Background And Aims: SARS-CoV-2 is a worldwide serious health problem. The aim of this study was to demonstrate the number of potentially infectious particles present during endoscopic procedures and find effective tools to eliminate the risks of SARS-CoV-2 infection while performing them.

Methods: An experimental model which focused on aerosol problematics was made in a specialized laboratory.

Hygroscopicity of secondary marine organic aerosols: Mixtures of alkylammonium salts and inorganic components.

Field studies have identified alkylammonium salts as important components of secondary marine organic aerosols. In this work, we study the hygroscopic behavior of laboratory-generated alkylammonium aerosol particles, including monomethylammonium chloride (MMACl), dimethylammonium chloride (DMACl), trimethylammonium chloride (TMACl), diethylammonium chloride (DEACl), and their mixtures with inorganic salts containing ammonium sulfate (NH)SO, sodium chloride NaCl, calcium nitrate Ca(NO) and sodium sulfate NaSO at different dry mass ratios with a hygroscopicity tandem differential mobility analyzer (HTDMA). The hygroscopic growth of pure alkylammonium salt particles (except for DEACl) reveals gradual water uptake over the whole studied range of relative humidities (RHs).

An evidence review of face masks against COVID-19.

The science around the use of masks by the public to impede COVID-19 transmission is advancing rapidly. In this narrative review, we develop an analytical framework to examine mask usage, synthesizing the relevant literature to inform multiple areas: population impact, transmission characteristics, source control, wearer protection, sociological considerations, and implementation considerations. A primary route of transmission of COVID-19 is via respiratory particles, and it is known to be transmissible from presymptomatic, paucisymptomatic, and asymptomatic individuals.

Three-Year Study of Markers of Oxidative Stress in Exhaled Breath Condensate in Workers Producing Nanocomposites, Extended by Plasma and Urine Analysis in Last Two Years.

Human data concerning exposure to nanoparticles are very limited, and biomarkers for monitoring exposure are urgently needed. In a follow-up of a 2016 study in a nanocomposites plant, in which only exhaled breath condensate (EBC) was examined, eight markers of oxidative stress were analyzed in three bodily fluids, i.e.

Atmospheric aerosol growth rates at different background station types.

Highly time-resolved particle number size distributions (PNSDs) were evaluated during 5 years (2013-2017) at four background stations in the Czech Republic located in different types of environments-urban background (Ústí nad Labem), industrial background (Lom), agricultural background (National Atmospheric Observatory Košetice), and suburban background (Prague-Suchdol). The PNSD data was used for new particle formation event determination as well as growth rate (GR) and condensation sink (CS) calculations. The differences or similarities of these parameters were evaluated from perspectives of the different pollution load, meteorological condition, and regional or long-range transport.

Nuclear Magnetic Resonance Aerosolomics: A Tool for Analysis of Polar Compounds in Atmospheric Aerosols.

Nuclear magnetic resonance aerosolomics was proposed as a new approach to the analysis of the water-soluble organic compound fraction in aerosol particulate matter. The identification of individual compounds is based on a comparison of precise chemical shifts in the H NMR spectrum with the signals in the standards library. For this purpose, Chenomx metabolomics software and a comprehensive spectra library of 150 compounds known from chemistry of aerosols were used.

The genotoxic effects in the leukocytes of workers handling nanocomposite materials.

The extensive development of nanotechnologies and nanomaterials poses a number of questions to toxicologists about the potential health risks of exposure to nanoparticles (NP). In this study, we analysed DNA damage in the leukocytes of 20 workers who were long-term exposed (18 ± 10 years) to NP in their working environment. Blood samples were collected in September 2016, before and after a shift, to assess (i) the chronic effects of NP on DNA (pre-shift samples) and (ii) the acute effects of exposure during the shift (the difference between pre- and post-shift samples).

Spatial-temporal variability of aerosol sources based on chemical composition and particle number size distributions in an urban settlement influenced by metallurgical industry.

The Moravian-Silesian region of the Czech Republic with its capital city Ostrava is a European air pollution hot spot for airborne particulate matter (PM). Therefore, the spatiotemporal variability assessment of source contributions to aerosol particles is essential for the successful abatement strategies implementation. Positive Matrix Factorization (PMF) was applied to highly-time resolved PM chemical composition (1 h resolution) and particle number size distribution (PNSD, 14 nm - 10 μm) data measured at the suburban (Ostrava-Plesná) and urban (Ostrava-Radvanice) residential receptor sites in parallel during an intensive winter campaign.

DNA Methylation Profiles in a Group of Workers Occupationally Exposed to Nanoparticles.

The risk of exposure to nanoparticles (NPs) has rapidly increased during the last decade due to the vast use of nanomaterials (NMs) in many areas of human life. Despite this fact, human biomonitoring studies focused on the effect of NP exposure on DNA alterations are still rare. Furthermore, there are virtually no epigenetic data available.

Dry powder inhaler of colistimethate sodium for lung infections in cystic fibrosis: optimization of powder construction.

Colistimethate sodium (CMS) for treatment of lung infections in cystic fibrosis patient was transformed into a dry powder for inhalation by spray drying. Design of Experiment was applied for understanding the role of the spray-drying process parameters on the critical quality attributes of the CMS spray-dried (SD) powders and agglomerates thereof. Eleven experimental SD microparticle powders were constructed under different process conditions according to a central composite design.

The repeated cytogenetic analysis of subjects occupationally exposed to nanoparticles: a pilot study.

The application of nanomaterials has been rapidly increasing during recent years. Inhalation exposure to nanoparticles (NP) may result in negative toxic effects but there is a critical lack of human studies, especially those related to possible DNA alterations. We analyzed pre-shift and post-shift a group of nanocomposite researchers with a long-term working background (17.

Leukocyte telomere length is not affected by long-term occupational exposure to nano metal oxides.

The aim of this study was to ascertain whether long-term occupational exposure to nanoparticles would affect relative leukocyte telomere length (LrTL). We analysed occupational exposure to size-resolved aerosol particles, with special emphasis on nanoparticles at two workshops: i/ the production of nanocomposites containing metal oxides; ii/ laboratory to test experimental exposure of nano-CuO to rodents. Thirty five exposed researchers (age 39.

Assessment of air pollution origin based on year-long parallel measurement of PM and PM at two suburban sites in Prague, Czech Republic.

From 2nd April 2008 to 28th March 2009, a total 248 daily samples of the PM and PM were collected every sixth day parallel at two suburban sites (Libuš and Suchdol) located at the two opposite sides (south and north, respectively) of Prague, Czech Republic. The PM samples were analyzed for ions by ion chromatography (IC), organic and elemental carbon (OC and EC) by OC/EC analyzer and PM samples also for 56 elements by inductively coupled plasma-mass spectrometry (ICP-MS). The average annual PM and PM was 24.