Oxidative stress and activation of H2A.X in lung alveolar epithelial cells (A549) by nanoparticulate carbon black

Fine airborne particulate matter enter the respiratory system, induce oxidative stress and initiate DNA damage. The aim of our study was the estimation of cell viability, oxidative stress, DNA damage, cell cycle alterations and activation of histone H2A.X. Experiments were done on lung alveolar epithelial (A549) cells grown for 24 h with 200 µg mL-1 coarse carbon black (CB), or nanoparticulate CB (NPCB). Neither CB nor glutathione depletion altered cell viability, growth rates, and H2A.X expression while NPCB decreased cell viability, increased oxidative stress and DNA damage. The cell cycle was blocked at G0/G1. NPCB but not CB increased expression and activation of H2A.X at mRNA and protein levels. Co-expression data point to γH2A.X as a major NPCB target, and show the interdependence of γH2A.X and oxidative stress. We conclude, that NPCB increases γ-H2A.X expression in A549 cells at mRNA and protein levels and stimulates H2A.X (Ser139), phosphorylation, associated with oxidative stress, the DNA damage response and G1 cell cycle arrest.

Research progress on the effects of gut microbiome on lung damage induced by particulate matter exposure

Air pollution is one of the top five causes of death in the world and has become a research hotspot. In the past, the health effects of particulate matter (PM), the main component of air pollutants, were mainly focused on the respiratory and cardiovascular systems. However, in recent years, the intestinal damage caused by PM and its relationship with gut microbiome (GM) homeostasis, thereby affecting the composition and function of GM and bringing disease burden to the host lung through different mechanisms, have attracted more and more attention. Therefore, this paper reviews the latest research progress in the effect of PM on GM-induced lung damage and its possible interaction pathways and explores the potential immune inflammatory mechanism with the gut-lung axis as the hub in order to understand the current research situation and existing problems, and to provide new ideas for further research on the relationship between PM pollution, GM, and lung damage.

X-ray fluorescence spectrometry for environmental analysis: Basic principles, instrumentation, applications and recent trends

In recent years, the conceptual advancement on green analytical chemistry (GAC) has moved in parallel with efforts to incorporate new screening or quantitative low-cost analytical tools to solve analytical problems. In this sense, the role of solid state techniques that allow the non-invasive analysis (or with a minimum sample treatment) of solid samples cannot be neglected. This review describes the basic principles, instrumentation and advances in the application of X-ray fluorescence instrumentation to the environmental sciences research topics, published between 2006 and 2020. Obviously, and because of the enormous number of works that can be found in the literature, it is not possible to exhaustively cover all published articles and the diversity of topics related to the environment in which a solid state technique like XRF has been applied successfully. It is a question of making a compilation of the instrumentation in use, the significant advances in XRF spectrometry and sample treatment strategies to highlight the potential of its implementation for environmental assessment.

Determination of the protein content of complex samples by aromatic amino acid analysis, liquid chromatography-UV absorbance, and colorimetry

Fast and accurate determination of the protein content of a sample is an important and non-trivial task of many biochemical, biomedical, food chemical, pharmaceutical, and environmental research activities. Different methods of total protein determination are used for a wide range of proteins with highly variable properties in complex matrices. These methods usually work reasonably well for proteins under controlled conditions, but the results for non-standard and complex samples are often questionable. Here, we compare new and well-established methods, including traditional amino acid analysis (AAA), aromatic amino acid analysis (AAAA) based on the amino acids phenylalanine and tyrosine, reversed-phase liquid chromatography of intact proteins with UV absorbance measurements at 220 and 280 nm (LC-220, LC-280), and colorimetric assays like Coomassie Blue G-250 dye-binding assay (Bradford) and bicinchoninic acid (BCA) assay. We investigated different samples, including proteins with challenging properties, chemical modifications, mixtures, and complex matrices like air particulate matter and pollen extracts. All methods yielded accurate and precise results for the protein and matrix used for calibration. AAA, AAAA with fluorescence detection, and the LC-220 method yielded robust results even under more challenging conditions (variable analytes and matrices). These methods turned out to be well-suited for reliable determination of the protein content in a wide range of samples, such as air particulate matter and pollen.

Urban conditions affect soil characteristics and physiological performance of three evergreen woody species

Physiological studies conducted mainly in metropolitan areas demonstrated that urban environments generate stressful conditions for plants. However, less attention has been paid to plant response to urban conditions in small cities. Here, we evaluated to what extent the health and physiological functions of some Mediterranean urban species [Quercus ilex L., Nerium oleander L. and Pittosporum tobira (Thunb.) W.T. Aiton] were impacted by urban and peri-urban conditions in Pisa (Italy), a small medieval city with narrow streets that impede efficient public transport causing oversized private transport. Experimental period spanned from late-summer to winter in concomitance with the sharp increase in air pollutants. Climate and air quality, soil physical and chemical properties, and plant physiological traits including leaf gas exchanges, chlorophyll fluorescence and leaf pigments were assessed. In soil, the organic carbon affected aggregates and water stability and the concentrations of some micro-elements decreased in winter. Air pollutants impaired leaf gas exchanges and photochemical processes at photosystem II, depending on species, season, and urban conditions. Shrubs were more susceptible than the tree species, highlighting that the latter adapted better to pollutants along an urban-peri-urban transect in Mediterranean environments. This study gives information on the physiological adaptability of some of the most frequent Mediterranean urban species to stressful conditions and demonstrated that, even in a small city, urban conditions influence the physiology and development of vegetation, affecting the plant health status and its ability to provide key ecosystem services.

Novel coronavirus disease 2019 (COVID-19) pandemic: From transmission to control with an interdisciplinary vision

There a lot of review papers addressing specific COVID-19 research sectors, then devoted to specialists. This review provides an in-depth summary of the available information about SARS-CoV-2 and the corresponding disease (also known as COVID-19), with a multi-disciplinary approach. After the paper introduction, the first section treats the virological characteristics of SARS-CoV-2, the medical implications of the infection, and the human susceptivity. Great attention is devoted to the factor affecting the infection routes, distinguishing among the possible human-to-human, environmental-to-human, and pollution-to-human transmission mechanisms. The second section is devoted to reporting the impact of SARS-CoV-2 not only on the healthcare systems but also on the economy and society. The third section is devoted to non-pharmaceutical behaviours against COVID-19. In this context, this review section presents an analysis of the European second wave allowing not only to focalize the importance of some restrictions, but also the relevance of social acceptance of some measures. The data reassumed in this work are very useful for interdisciplinary researchers that work in a team to find the basic available information about all the aspects connected with this pandemic (from virus diffusion mechanism to health information, from economic and social impacts to measures to reduce the pandemic spread), with great attention to social acceptance of restriction measures and of vaccines (that currently results to be insufficient to achieve community immunity). Then, this review paper highlights the fundamental role of the trans-multi-disciplinary research that is devoted not only to understand the basics of the pandemic to propose solutions but has also the commitment to find strategies to increase population resilience. For this aim, the authors strongly suggest the establishment of an international health-care trans-multi-disciplinary workforce devoted to investigate, mitigate, and control also future viral events.

Novel coronavirus disease 2019 (COVID-19) pandemic: From transmission to control with an interdisciplinary vision

There a lot of review papers addressing specific COVID-19 research sectors, then devoted to specialists. This review provides an in-depth summary of the available information about SARS-CoV-2 and the corresponding disease (also known as COVID-19), with a multi-disciplinary approach. After the paper introduction, the first section treats the virological characteristics of SARS-CoV-2, the medical implications of the infection, and the human susceptivity. Great attention is devoted to the factor affecting the infection routes, distinguishing among the possible human-to-human, environmental-to-human, and pollution-to-human transmission mechanisms. The second section is devoted to reporting the impact of SARS-CoV-2 not only on the healthcare systems but also on the economy and society. The third section is devoted to non-pharmaceutical behaviours against COVID-19. In this context, this review section presents an analysis of the European second wave allowing not only to focalize the importance of some restrictions, but also the relevance of social acceptance of some measures. The data reassumed in this work are very useful for interdisciplinary researchers that work in a team to find the basic available information about all the aspects connected with this pandemic (from virus diffusion mechanism to health information, from economic and social impacts to measures to reduce the pandemic spread), with great attention to social acceptance of restriction measures and of vaccines (that currently results to be insufficient to achieve community immunity). Then, this review paper highlights the fundamental role of the trans-multi-disciplinary research that is devoted not only to understand the basics of the pandemic to propose solutions but has also the commitment to find strategies to increase population resilience. For this aim, the authors strongly suggest the establishment of an international health-care trans-multi-disciplinary workforce devoted to investigate, mitigate, and control also future viral events.

Genotoxicity and DNA damage signaling in response to complex mixtures of PAHs in biomass burning particulate matter from cashew nut roasting

Approximately 3 billion people world-wide are exposed to air pollution from biomass burning. Herein, particulate matter (PM) emitted from artisanal cashew nut roasting, an important economic activity worldwide, was investigated. This study focused on: i) chemical characterization of polycyclic aromatic hydrocarbons (PAHs) and oxygenated (oxy-) PAHs; ii) intracellular levels of reactive oxygen species (ROS); iii) genotoxic effects and time- and dose-dependent activation of DNA damage signaling, and iv) differential expression of genes involved in xenobiotic metabolism, inflammation, cell cycle arrest and DNA repair, using A549 lung cells. Among the PAHs, chrysene, benzo[a]pyrene (B[a]P), benzo[b]fluoranthene, and benz[a]anthracene showed the highest concentrations (7.8-10 ng/m³), while benzanthrone and 9,10-anthraquinone were the most abundant oxy-PAHs. Testing of PM extracts was based on B[a]P equivalent doses (B[a]P_eq). IC₅₀ values for viability were 5.7 and 3.0 nM B[a]P_eq at 24 h and 48 h, respectively. At these low doses, we observed a time- and dose-dependent increase in intracellular levels of ROS, genotoxicity (DNA strand breaks) and DNA damage signaling (phosphorylation of the protein checkpoint kinase 1 - Chk1). In comparison, effects of B[a]P alone was observed at micromolar range. To our knowledge, no previous study has demonstrated an activation of pChk1, a biomarker used to estimate the carcinogenic potency of PAHs in vitro, in lung cells exposed to cashew nut roasting extracts. Sustained induction of expression of several important stress response mediators of xenobiotic metabolism (CYP1A1, CYP1B1), ROS and pro-inflammatory response (IL-8, TNF-α, IL-2, COX2), and DNA damage response (CDKN1A and DDB2) was also identified. In conclusion, our data show high potency of cashew nut roasting PM to induce cellular stress including genotoxicity, and more potently when compared to B[a]P alone. Our study provides new data that will help elucidate the toxic effects of low-levels of PAH mixtures from air PM generated by cashew nut roasting.

Occurrence of organic phosphates in particulate matter of the vehicle exhausts and outdoor environment - A case study

The occurrence and concentrations of a wide range of organic phosphates (OPEs) in vehicle's exhaust (VPM), ambient air particulate matter (APM), and soil of various urban environments were researched. VPM comes from passenger cars, commercial vehicles, marine and bus engines emitted in New European Driving Cycle tests whereas APM was sampled in several sites of the Upper Silesia region (Poland). APM and VPM collected on filters and soil from the same locations as APM sampling sites were extracted with dichloromethane and extracts analyzed by gas chromatography-mass spectrometry. The OPEs found include aryl phosphates such as triphenyl phosphate (TPhP) and tricresyl phosphate (TCP), alkyl phosphates - triethyl phosphate (TEP), tripropyl phosphate (TPP), tributyl phosphate (TBP) and tri(butoxyethyl)phosphate (TBEP), and alkylchlorinated phosphates including tris-(2-chloroisopropyl) phosphate (TCiPP) and tris(2-chloroethyl) phosphate (TCEP). Occurrence and concentrations of these compounds in the PM investigated are highly variable. It was found that total concentrations in APM are directly related to traffic density in particular sites of the urban environment and a style of a vehicle driving. The highest emission of OPEs was found at a crossroad and city center sites where traffic is the densest and vehicles stops and starts are frequent. Village and residential areas were less exposed to OPEs emission. Since OPEs concentrations show exponential correlations to each other also human exposure to these compounds increases exponentially with increasing traffic density. High TEP and TBP level is tentatively proposed as an indicator of emission from petrol-fueled cars. Concentrations of OPEs in some soil are related to their emission to the air and resistance to degradation of a particular compound since only the most resistant TCiPP and TPhP were identified in soil extracts.

Evaluating the mutagenicity of the water-soluble fraction of air particulate matter: A comparison of two extraction strategies

Many studies have focused on assessing the genotoxic potential of the organic fraction of airborne particulate matter. However, the determination of water-soluble compounds, and the evaluation of the toxic effects of these elements can also provide valuable information for the development of novel strategies to control atmospheric air pollution. To determine an appropriate extraction method for assessing the mutagenicity of the water-soluble fraction of PM, we performed microwave assisted (MW) and ultrasonic bath (US) extractions, using water as solvent, in eight different air samples (TSP and PM10). Mutagenicity and extraction performances were evaluated using the Salmonella/microsome assay with strains TA98 and TA100, followed by chemical determination of water-soluble metals. Additionally, we evaluated the chemical and biological stability of the extracts testing their mutagenic potential and chemically determining elements present in the samples along several periods after extraction. Reference material SRM 1648a was used. The comparison of MW and US extractions did not show differences on the metals concentrations, however positive mutagenic responses were detected with TA98 strain in all samples extracted using the MW method, but not with the US bath extraction. The recovery, using reference material was better in samples extracted with MW. We concluded that the MW extraction is more efficient to assess the mutagenic activity of the soluble fraction of airborne PM. We also observed that the extract freezing and storage over 60 days has a significant effect on the mutagenic and analytical results on PM samples, and should be avoided.

Development of two fine particulate matter standard reference materials (<4 μm and <10 μm) for the determination of organic and inorganic constituents

Two new Standard Reference Materials (SRMs), SRM 2786 Fine Particulate Matter (<4 μm) and SRM 2787 Fine Particulate Matter (<10 μm) have been developed in support of the US Environmental Protection Agency's National Ambient Air Quality Standards for particulate matter (PM). These materials have been characterized for the mass fractions of selected polycyclic aromatic hydrocarbons (PAHs), nitrated PAHs, brominated diphenyl ether (BDE) congeners, hexabromocyclododecane (HBCD) isomers, sugars, polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners, and inorganic constituents, as well as particle-size characteristics. These materials are the first Certified Reference Materials available to support measurements of both organic and inorganic constituents in fine PM. In addition, values for PAHs are available for RM 8785 Air Particulate Matter on Filter Media. As such, these SRMs will be useful as quality control samples for ensuring compatibility of results among PM monitoring studies and will fill a void to assess the accuracy of analytical methods used in these studies. Graphical Abstract Removal of PM from filter for the preparation of SRM 2786 Fine Particulate Matter.