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1.
Can Vet J ; 65(7): 707-711, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38952762

ABSTRACT

A swine production system had 3 sections located a few kilometers apart. Sections A and C contained several thousand sows and nursery and finishing pigs. Section B, located between the other 2 sections, was the smallest and had 6 finishing sites and 2 sow sites. The entire system was infected with porcine reproductive and respiratory syndrome virus, Mycoplasma hyopneumoniae, and Actinobacillus pleuropneumoniae. Section B was depopulated, cleaned, disinfected, and repopulated with negative gilts. Despite extreme measures, recontamination occurred for each pathogen, with aerosol considered the most plausible contamination source.


Transmission suspectée d'agents pathogènes porcins par aérosol : un cas de terrainUn système de production porcine comportait 3 sections situées à quelques kilomètres l'une de l'autre. Les sections A et C contenaient plusieurs milliers de truies et de porcs en maternité et en finition. La section B, située entre les 2 autres sections, était la plus petite et comptait 6 sites de finition et 2 sites de truies. L'ensemble du système était infecté par le virus du syndrome reproducteur et respiratoire porcin, Mycoplasma hyopneumoniae et Actinobacillus pleuropneumoniae. La section B a été dépeuplée, nettoyée, désinfectée et repeuplée de cochettes négatives. Malgré des mesures extrêmes, une recontamination s'est produite pour chaque agent pathogène, les aérosols étant considérés comme la source de contamination la plus plausible.(Traduit par Dr Serge Messier).


Subject(s)
Actinobacillus pleuropneumoniae , Aerosols , Mycoplasma hyopneumoniae , Porcine respiratory and reproductive syndrome virus , Swine Diseases , Animals , Swine , Swine Diseases/transmission , Swine Diseases/microbiology , Swine Diseases/virology , Mycoplasma hyopneumoniae/isolation & purification , Actinobacillus pleuropneumoniae/isolation & purification , Porcine respiratory and reproductive syndrome virus/isolation & purification , Actinobacillus Infections/veterinary , Actinobacillus Infections/transmission , Actinobacillus Infections/microbiology , Pneumonia of Swine, Mycoplasmal/transmission , Female , Porcine Reproductive and Respiratory Syndrome/transmission , Animal Husbandry
2.
J Gastric Cancer ; 24(3): 246-256, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38960884

ABSTRACT

PURPOSE: Peritoneal carcinomatosis (PC) presents a major challenge in the treatment of late-stage, solid tumors, with traditional therapies limited by poor drug penetration. We evaluated a novel hyperthermic pressurized intraperitoneal aerosol chemotherapy (HPIPAC) system using a human abdominal cavity model for its efficacy against AGS gastric cancer cells. MATERIALS AND METHODS: A model simulating the human abdominal cavity and AGS gastric cancer cell line cultured dishes were used to assess the efficacy of the HPIPAC system. Cell viability was measured to evaluate the impact of HPIPAC under 6 different conditions: heat alone, PIPAC with paclitaxel (PTX), PTX alone, normal saline (NS) alone, heat with NS, and HPIPAC with PTX. RESULTS: Results showed a significant reduction in cell viability with HPIPAC combined with PTX, indicating enhanced cytotoxic effects. Immediately after treatment, the average cell viability was 66.6%, which decreased to 49.2% after 48 hours and to a further 19.6% after 120 hours of incubation, demonstrating the sustained efficacy of the treatment. In contrast, control groups exhibited a recovery in cell viability; heat alone showed cell viability increasing from 90.8% to 94.4%, PIPAC with PTX from 82.7% to 89.7%, PTX only from 73.3% to 74.8%, NS only from 90.9% to 98.3%, and heat with NS from 74.4% to 84.7%. CONCLUSIONS: The HPIPAC system with PTX exhibits a promising approach in the treatment of PC in gastric cancer, significantly reducing cell viability. Despite certain limitations, this study highlights the system's potential to enhance treatment outcomes. Future efforts should focus on refining HPIPAC and validating its effectiveness in clinical settings.


Subject(s)
Aerosols , Cell Survival , Hyperthermic Intraperitoneal Chemotherapy , Paclitaxel , Peritoneal Neoplasms , Stomach Neoplasms , Humans , Stomach Neoplasms/drug therapy , Stomach Neoplasms/pathology , Peritoneal Neoplasms/drug therapy , Peritoneal Neoplasms/secondary , Peritoneal Neoplasms/pathology , Peritoneal Neoplasms/therapy , Paclitaxel/pharmacology , Paclitaxel/administration & dosage , Hyperthermic Intraperitoneal Chemotherapy/methods , Cell Survival/drug effects , Cell Line, Tumor , Hyperthermia, Induced/methods , Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Agents, Phytogenic/pharmacology
3.
Environ Monit Assess ; 196(8): 714, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38976077

ABSTRACT

Human-generated aerosol pollution gradually modifies the atmospheric chemical and physical attributes, resulting in significant changes in weather patterns and detrimental effects on agricultural yields. The current study assesses the loss in agricultural productivity due to weather and anthropogenic aerosol variations for rice and maize crops through the analysis of time series data of India spanning from 1998 to 2019. The average values of meteorological variables like maximum temperature (TMAX), minimum temperature (TMIN), rainfall, and relative humidity, as well as aerosol optical depth (AOD), have also shown an increasing tendency, while the average values of soil moisture and fraction of absorbed photosynthetically active radiation (FAPAR) have followed a decreasing trend over that period. This study's primary finding is that unusual variations in weather variables like maximum and minimum temperature, rainfall, relative humidity, soil moisture, and FAPAR resulted in a reduction in rice and maize yield of approximately (2.55%, 2.92%, 2.778%, 4.84%, 2.90%, and 2.82%) and (5.12%, 6.57%, 6.93%, 6.54%, 4.97%, and 5.84%), respectively. However, the increase in aerosol pollution is also responsible for the reduction of rice and maize yield by 7.9% and 8.8%, respectively. In summary, the study presents definitive proof of the detrimental effect of weather, FAPAR, and AOD variability on the yield of rice and maize in India during the study period. Meanwhile, a time series analysis of rice and maize yields revealed an increasing trend, with rates of 0.888 million tons/year and 0.561 million tons/year, respectively, due to the adoption of increasingly advanced agricultural techniques, the best fertilizer and irrigation, climate-resilient varieties, and other factors. Looking ahead, the ongoing challenge is to devise effective long-term strategies to combat air pollution caused by aerosols and to address its adverse effects on agricultural production and food security.


Subject(s)
Aerosols , Agriculture , Air Pollutants , Environmental Monitoring , Oryza , Zea mays , Oryza/growth & development , India , Aerosols/analysis , Zea mays/growth & development , Agriculture/methods , Air Pollutants/analysis , Climate , Air Pollution/statistics & numerical data , Crops, Agricultural , Weather
4.
J Environ Manage ; 365: 121644, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38963970

ABSTRACT

The Earth's atmosphere contains ultrafine particles known as aerosols, which can be either liquid or solid particles suspended in gas. These aerosols originate from both natural sources and human activities, termed primary and secondary sources respectively. They have significant impacts on the environment, particularly when they transform into ultrafine particles or aerosol nanoparticles, due to their extremely fine atomic structure. With this context in mind, this review aims to elucidate the fundamentals of atmospheric-derived aerosol nanoparticles, covering their various sources, impacts, and methods for control and management. Natural sources such as marine, volcanic, dust, and bioaerosols are discussed, along with anthropogenic sources like the combustion of fossil fuels, biomass, and industrial waste. Aerosol nanoparticles can have several detrimental effects on ecosystems, prompting the exploration and analysis of eco-friendly, sustainable technologies for their removal or mitigation.Despite the adverse effects highlighted in the review, attention is also given to the generation of aerosol-derived atmospheric nanoparticles from biomass sources. This finding provides valuable scientific evidence and background for researchers in fields such as epidemiology, aerobiology, and toxicology, particularly concerning atmospheric nanoparticles.


Subject(s)
Aerosols , Atmosphere , Ecosystem , Nanoparticles , Aerosols/analysis , Nanoparticles/chemistry , Atmosphere/chemistry , Air Pollutants/analysis , Humans , Environmental Monitoring , Particulate Matter/analysis
5.
Sci Rep ; 14(1): 15963, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38987323

ABSTRACT

The recent COVID-19 pandemic has raised interest in efficient air disinfection solutions. The application of germicidal ultraviolet (GUV) irradiation is an excellent contender to prevent airborne transmission of COVID-19, as well as other existing and future infectious airborne diseases. While GUV has already been proven effective in inactivating SARS-CoV-2, quantitative data on UV susceptibility and dose requirements, needed to predict and optimize the performance of GUV solutions, is still limited. In this study, the UV susceptibility of aerosolized SARS-CoV-2 to 254 nm ultraviolet (UV) irradiation is investigated. This is done by employing 3D computational fluid dynamics based simulations of SARS-CoV-2 inactivation in a test chamber equipped with an upper-room UV-C luminaire and comparing the results to previously published measurements performed in the same test chamber. The UV susceptibility found in this study is (0.6 ± 0.2) m2/J, which is equivalent to a D90 dose between 3 and 6 J/m2. These values are in the same range as previous estimations based on other corona viruses and inactivation data reported in literature.


Subject(s)
COVID-19 , Disinfection , SARS-CoV-2 , Ultraviolet Rays , SARS-CoV-2/radiation effects , Disinfection/methods , COVID-19/prevention & control , COVID-19/virology , COVID-19/transmission , Humans , Aerosols , Hydrodynamics , Computer Simulation , Virus Inactivation/radiation effects
6.
Environ Microbiol Rep ; 16(4): e13303, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38982659

ABSTRACT

The development of effective methods for the surveillance of seasonal respiratory viruses is required for the timely management of outbreaks. We aimed to survey Influenza-A, Influenza-B, RSV-A, Rhinovirus and SARS-CoV-2 surveillance in a tertiary hospital and a campus over 5 months. The effectiveness of air screening as an early warning system for respiratory viruses was evaluated in correlation with respiratory tract panel test results. The overall viral positivity was higher on the campus than in the hospital (55.0% vs. 38.0%). Influenza A was the most prevalent pathogen in both locations. There were two influenza peaks (42nd and 49th weeks) in the hospital air, and a delayed peak was detected on campus in the 1st-week of January. Panel tests indicated a high rate of Influenza A in late December. RSV-A-positivity was higher on the campus than the hospital (21.6% vs. 7.4%). Moreover, we detected two RSV-A peaks in the campus air (48th and 51st weeks) but only one peak in the hospital and panel tests (week 49). Although rhinovirus was the most common pathogen in panel tests, rhinovirus positivity was low in air samples. The air screening for Influenza-B and SARS-Cov-2 revealed comparable positivity rates with panel tests. Air screening can be integrated into surveillance programs to support infection control programs for potential epidemics of respiratory virus infections except for rhinoviruses.


Subject(s)
COVID-19 , Rhinovirus , SARS-CoV-2 , Humans , Rhinovirus/isolation & purification , SARS-CoV-2/isolation & purification , SARS-CoV-2/genetics , COVID-19/epidemiology , COVID-19/diagnosis , COVID-19/virology , Aerosols/analysis , Respiratory Tract Infections/virology , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/diagnosis , Air Microbiology , Influenza, Human/epidemiology , Influenza, Human/virology , Air Pollution, Indoor/analysis , Influenza A virus/isolation & purification , Seasons , Epidemics , Environmental Monitoring/methods , Influenza B virus/isolation & purification , Viruses/isolation & purification , Viruses/classification , Viruses/genetics
7.
PLoS One ; 19(7): e0306985, 2024.
Article in English | MEDLINE | ID: mdl-39008462

ABSTRACT

BACKGROUND: Amazonas was one of the most impacted Brazilian states by the COVID-19 pandemic. Mortality rates were high, and the health systems collapsed. It is important to identify possible intermediate reservoirs to avoid animal-to-human contamination. Several tropical fish are of commercial interest and are sold in large open-air markets in the region, representing a large economic and dietary importance. OBJECTIVES: This study aimed to verify if fish species of commercial importance, aerosols, and fish wastewater in local open-air markets, at a major capital city in the western Brazilian Amazon, are contaminated by SARS-CoV-2. METHODS: 488 fish, 50 aerosol, and 45 wastewater samples were analyzed for the presence of SARS-CoV-2. The samples were subjected to extraction using the BIOGENE Viral DNA/RNA Extraction kit, and the molecular diagnosis was tested for SARS-CoV-2 using the Bio-Manguinhos SARS-CoV-2 (EDx) Molecular Kit. RESULTS: It was not possible to detect the virus (Ct≤40, for Gene E) in these samples, however, in 181 samples of fish it was possible to detect the human RP gene (Ct≤35, for the RP Gene), indicating human contact. There was a high number of COVID-19 diagnoses in all city districts in which the samples were collected, showing that SARS-CoV-2 was circulating. CONCLUSION: This study indicates that fish of local commercial importance do not carry SARS-CoV-2 viral particles, despite circulation of SARS-CoV-2, and are not an important source of animal-to-human contamination. Despite these results, the human RP gene was found detectable in fish, air, and fish wastewater, showing that such places may carry human pathogens.


Subject(s)
COVID-19 , Fishes , SARS-CoV-2 , Animals , SARS-CoV-2/isolation & purification , SARS-CoV-2/genetics , Humans , Brazil/epidemiology , COVID-19/virology , COVID-19/epidemiology , Fishes/virology , Wastewater/virology , Aerosols , RNA, Viral/genetics , RNA, Viral/isolation & purification , RNA, Viral/analysis
8.
Environ Sci Technol ; 58(28): 12585-12597, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38956968

ABSTRACT

Elevated levels of atmospheric molecular chlorine (Cl2) have been observed during the daytime in recent field studies in China but could not be explained by the current chlorine chemistry mechanisms in models. Here, we propose a Cl2 formation mechanism initiated by aerosol iron photochemistry to explain daytime Cl2 formation. We implement this mechanism into the GEOS-Chem chemical transport model and investigate its impacts on the atmospheric composition in wintertime North China where high levels of Cl2 as well as aerosol chloride and iron were observed. The new mechanism accounts for more than 90% of surface air Cl2 production in North China and consequently increases the surface air Cl2 abundances by an order of magnitude, improving the model's agreement with observed Cl2. The presence of high Cl2 significantly alters the oxidative capacity of the atmosphere, with a factor of 20-40 increase in the chlorine radical concentration and a 20-40% increase in the hydroxyl radical concentration in regions with high aerosol chloride and iron loadings. This results in an increase in surface air ozone by about 10%. This new Cl2 formation mechanism will improve the model simulation capability for reactive chlorine abundances in the regions with high emissions of chlorine and iron.


Subject(s)
Aerosols , Atmosphere , Chlorine , Iron , Oxidation-Reduction , Chlorine/chemistry , China , Iron/chemistry , Atmosphere/chemistry , Air Pollutants/chemistry , Photochemistry
9.
J Zhejiang Univ Sci B ; 25(7): 628-632, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39011682

ABSTRACT

Airborne transmission is among the most frequent types of nosocomial infection. Recent years have witnessed frequent outbreaks of airborne diseases, such as severe acute respiratory syndrome (SARS) in 2002, Middle East respiratory syndrome (MERS) in 2012, and coronavirus disease 2019 (COVID-19), with the latter being on the rampage since the end of 2019 and bringing the effect of aerosols on health back to the fore (Gralton et al., 2011; Wang et al., 2021). An increasing number of studies have shown that certain highly transmissible pathogens can maintain long-term stability and efficiently spread through aerosols (Leung, 2021; Lv et al., 2021). As reported previously, influenza viruses that can spread efficiently through aerosols remain stable for a longer period compared to those that cannot. The World Health Organization (WHO) has stated that aerosol-generating procedures (AGPs) play an important role in aerosol transmission in hospitals (Calderwood et al., 2021). AGPs, referring to medical procedures that produce aerosols, including dental procedures, endotracheal intubation, sputum aspiration, and laparoscopic surgeries, have been reported to be significantly associated with an increased risk of nosocomial infection among medical personnel (Hamilton, 2021).


Subject(s)
Aerosols , COVID-19 , Cross Infection , Endoscopes , SARS-CoV-2 , Humans , Cross Infection/transmission , Cross Infection/prevention & control , COVID-19/transmission , SARS-CoV-2/isolation & purification , Pandemics , Coronavirus Infections/transmission , Pneumonia, Viral/transmission , Disinfection/methods , Betacoronavirus , Air Microbiology
10.
Molecules ; 29(13)2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38999084

ABSTRACT

Sensitively detecting hazardous and suspected bioaerosols is crucial for safeguarding public health. The potential impact of pollen on identifying bacterial species through fluorescence spectra should not be overlooked. Before the analysis, the spectrum underwent preprocessing steps, including normalization, multivariate scattering correction, and Savitzky-Golay smoothing. Additionally, the spectrum was transformed using difference, standard normal variable, and fast Fourier transform techniques. A random forest algorithm was employed for the classification and identification of 31 different types of samples. The fast Fourier transform improved the classification accuracy of the sample excitation-emission matrix fluorescence spectrum data by 9.2%, resulting in an accuracy of 89.24%. The harmful substances, including Staphylococcus aureus, ricin, beta-bungarotoxin, and Staphylococcal enterotoxin B, were clearly distinguished. The spectral data transformation and classification algorithm effectively eliminated the interference of pollen on other components. Furthermore, a classification and recognition model based on spectral feature transformation was established, demonstrating excellent application potential in detecting hazardous substances and protecting public health. This study provided a solid foundation for the application of rapid detection methods for harmful bioaerosols.


Subject(s)
Algorithms , Pollen , Spectrometry, Fluorescence , Staphylococcus aureus , Pollen/chemistry , Spectrometry, Fluorescence/methods , Staphylococcus aureus/classification , Staphylococcus aureus/isolation & purification , Hazardous Substances/analysis , Hazardous Substances/classification , Enterotoxins/analysis , Ricin/analysis , Aerosols/analysis , Fourier Analysis
11.
Chem Res Toxicol ; 37(7): 1113-1120, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38957009

ABSTRACT

Electronic cigarettes (ECs) emit many toxic substances, including metals, that can pose a threat to users and the environment. The toxicity of the emitted metals depends on their oxidation states. Hence, this study examines the oxidation states of metals observed in EC aerosols. X-ray photoelectron spectroscopy analysis of the filters that collected EC aerosols identified the oxidation states of five primary metals (based on surface sample analysis), including chromium(III) (close to 100%) under low power setting while a noticeable amount of chromium(VI) (15%) at higher power settings of the EC, and copper(II) (100%), zinc(II) (100%), nickel(II) (100%), lead(II) (65%), and lead(IV) (35%) regardless of power settings. This observation indicates that the increased temperature due to higher power settings could alter the oxidation states of certain metals. We noted that many metals were in their lesser toxic states; however, inhaling these metals may still pose health risks.


Subject(s)
Aerosols , Electronic Nicotine Delivery Systems , Oxidation-Reduction , Aerosols/chemistry , Metals/chemistry
12.
J Sep Sci ; 47(14): e2400250, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39034833

ABSTRACT

Reconstituted tobacco (RT) is a product made by reprocessing tobacco waste, experiencing a growing demand for heat-not-burn products. The purpose of this study is to analyze the main flavor ingredients in RT aerosol, as well as the transfer behavior of key flavor substances from substrates to aerosol and the concentrations of these compounds in the substrate after heating. First, we demonstrated that the odor of four RT aerosol samples could be distinguished using an electronic nose. Through non-targeted analysis, 93 volatile compounds were detected by gas chromatography-mass spectrometry, and 286 non/semi-volatile compounds were identified by ultra-high-performance liquid electrophoresis chromatography-mass spectrometry in aerosol. Furthermore, we found that the formation of RT aerosol involves primarily evaporation and distillation, however, the total content delivered from unheated RT samples to aerosol remains relatively low due to compound volatility and cigarette filtration. Thermal reactions during heating indicated the pyrolysis of chlorogenic acid to generate catechol and resorcinol, while Maillard reactions involving glucose and proline produced 2,3-dihydro-3,5-dihydroxy-6-methyl-4h-pyran-4-one. The study highlighted that heating RT at approximately 300°C could mitigate the production of harmful substances while still providing a familiar sensory experience with combusted tobacco.


Subject(s)
Flavoring Agents , Gas Chromatography-Mass Spectrometry , Nicotiana , Flavoring Agents/analysis , Flavoring Agents/chemistry , Nicotiana/chemistry , Hot Temperature , Aerosols/chemistry , Aerosols/analysis , Volatile Organic Compounds/analysis , Volatile Organic Compounds/chemistry , Tobacco Products/analysis , Heating , Odorants/analysis
13.
Anticancer Res ; 44(7): 3043-3050, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38925817

ABSTRACT

BACKGROUND/AIM: This study evaluated the feasibility and safety of whole-body hyperthermia pressurized intraperitoneal aerosol chemotherapy (WBH-PIPAC) in patients with peritoneal surface malignancies. PATIENTS AND METHODS: This study retrospectively analyzed a database of 28 patients who had received one cycle of normothermic PIPAC prior to repetitive WBH-PIPACs. WBH (39-40°C) was induced using a Water-filtered infrared A device. Doxorubicin plus cisplatin or oxaliplatin was nebulized into a constant capnoperitoneum of 20 mmHg for 30 min at doses of 6.0 mg, 30.0 mg, or 120 mg per m2 body surface area, respectively. The primary outcome measures were feasibility and perioperative complications. RESULTS: The median age was 62 years (range=45-78 years). Primary tumor sites included the upper gastrointestinal tract (n=9), colon/rectum (n=7), hepato-pancreato-biliary system (n=3), peritoneum (n=2), ovaries (n=2), and unknown primary (n=5). The induction of WBH failed in one patient (6 liters ascites). After a median warming period of 95 min (53-117 min), the median rectal temperature (Trec) was 39.5°C (39.2-39.9°C). No hyperthermia-related side effects were observed. Twenty-seven patients received 50 WBH-PIPACs. The median time of therapeutic capnoperitoneum and treatment time with Trec ≥39°C was 39 min (37-43 min) and 66 min (53-69 min), respectively. The overall rate of postoperative procedure-related complications was 9/50, including seven grade I and two grade II complications. There were no grade III-V complications. CONCLUSION: In a highly selected group of patients, the feasibility and perioperative safety of WBH-PIPAC was comparable to normothermic PIPAC.


Subject(s)
Aerosols , Feasibility Studies , Peritoneal Neoplasms , Humans , Middle Aged , Female , Aged , Male , Peritoneal Neoplasms/drug therapy , Peritoneal Neoplasms/therapy , Retrospective Studies , Hyperthermia, Induced/methods , Hyperthermia, Induced/adverse effects , Cisplatin/administration & dosage , Cisplatin/adverse effects , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Hyperthermic Intraperitoneal Chemotherapy/methods , Hyperthermic Intraperitoneal Chemotherapy/adverse effects , Oxaliplatin/administration & dosage , Oxaliplatin/adverse effects , Oxaliplatin/therapeutic use
14.
Environ Sci Technol ; 58(25): 11118-11127, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38864774

ABSTRACT

Intermediate volatility organic compounds (IVOCs) are important precursors to secondary organic aerosols (SOAs), but they are often neglected in studies concerning SOA formation. This study addresses the significant issue of IVOCs emissions in the Qinghai-Tibetan plateau (QTP), where solid fuels are extensively used under incomplete combustion conditions for residential heating and cooking. Our field measurement data revealed an emission factor of the total IVOCs (EFIVOCs) ranging from 1.56 ± 0.03 to 9.97 ± 3.22 g/kg from various combustion scenarios in QTP. The markedly higher EFIVOCs in QTP than in plain regions can be attributed to oxygen-deficient conditions. IVOCs were dominated by gaseous phase emissions, and the primary contributors of gaseous and particulate phase IVOCs are the unresolved complex mixture and alkanes, respectively. Total IVOCs emissions during the heating and nonheating seasons in QTP were estimated to be 31.7 ± 13.8 and 6.87 ± 0.45 Gg, respectively. The estimated SOA production resulting from combined emissions of IVOCs and VOCs is nearly five times higher than that derived from VOCs alone. Results from this study emphasized the pivotal role of IVOCs emissions in air pollution and provided a foundation for compiling emission inventories related to solid fuel combustion and developing pollution prevention strategies.


Subject(s)
Aerosols , Air Pollutants , Coal , Volatile Organic Compounds , Volatile Organic Compounds/analysis , Air Pollutants/analysis , China , Animals , Tibet , Environmental Monitoring
15.
Environ Sci Technol ; 58(25): 11105-11117, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38866390

ABSTRACT

Volatile chemical products (VCPs) are increasingly recognized as significant sources of volatile organic compounds (VOCs) in urban atmospheres, potentially serving as key precursors for secondary organic aerosol (SOA) formation. This study investigates the formation and physicochemical transformations of VCP-derived SOA, produced through ozonolysis of VOCs evaporated from a representative room deodorant air freshener, focusing on the effects of aerosol evaporation on its molecular composition, light absorption properties, and reactive oxygen species (ROS) generation. Following aerosol evaporation, solutes become concentrated, accelerating reactions within the aerosol matrix that lead to a 42% reduction in peroxide content and noticeable browning of the SOA. This process occurs most effectively at moderate relative humidity (∼40%), reaching a maximum solute concentration before aerosol solidification. Molecular characterization reveals that evaporating VCP-derived SOA produces highly conjugated nitrogen-containing products from interactions between existing or transformed carbonyl compounds and reduced nitrogen species, likely acting as chromophores responsible for the observed brownish coloration. Additionally, the reactivity of VCP-derived SOA was elucidated through heterogeneous oxidation of sulfur dioxide (SO2), which revealed enhanced photosensitized sulfate production upon drying. Direct measurements of ROS, including singlet oxygen (1O2), superoxide (O2•-), and hydroxyl radicals (•OH), showed higher abundances in dried versus undried SOA samples under light exposure. Our findings underscore that drying significantly alters the physicochemical properties of VCP-derived SOA, impacting their roles in atmospheric chemistry and radiative balance.


Subject(s)
Aerosols , Volatile Organic Compounds , Volatile Organic Compounds/chemistry , Oxidation-Reduction , Air Pollutants/chemistry , Reactive Oxygen Species/chemistry , Atmosphere/chemistry
16.
ACS Sens ; 9(6): 2915-2924, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38848499

ABSTRACT

Health and security concerns have made it essential to develop integrated, continuous collection and sensing platforms that are compact and capable of real-time detection. In this study, we numerically investigate the flow physics associated with the single-step collection and enrichment of aerosolized polystyrene microparticles into a flowing liquid using a stratified air-water flow in a U-shaped microchannel. We validate our simulation results by comparing them to experimental data from the literature. Additionally, we fabricate an identical microfluidic device using PDMS-based soft lithography and test it to corroborate the previously published experimental data. Diversion and entrapment efficiencies are used as evaluation metrics, both of which increase with increasing particle diameter and superficial air inlet velocity. Overall, our ANSYS Fluent two-dimensional (2D) and three-dimensional (3D) multiphase flow simulations exhibit a good agreement with our experimental data and data in the literature (average deviation of ∼11%) in terms of diversion efficiency. Simulations also found the entrapment efficiency to be lower than the diversion efficiency, indicating discrepancies in the literature in terms of captured particles. The effect of the Dean force on the flow physics was also investigated using 3D simulations. We found that the effect of the Dean flow was more dominant relative to the centrifugal force on the smaller particles (e.g., 0.65 µm) compared to the larger particles (e.g., 2.1 µm). Increasing the superficial air inlet velocity also increases the effect of the centrifugal forces relative to the Dean forces. Overall, this experimentally validated multiphase model decouples and investigates the multiple and simultaneous forces on aerosolized particles flowing through a curved microchannel, which is crucial for designing more efficient capture devices. Once integrated with a microfluidic-based biosensor, this stratified flow-based microfluidic biothreat capture platform should deliver continuous sensor-ready enriched biosamples for real-time sensing.


Subject(s)
Aerosols , Particle Size , Polystyrenes , Aerosols/chemistry , Aerosols/analysis , Polystyrenes/chemistry , Microfluidic Analytical Techniques/instrumentation , Microfluidic Analytical Techniques/methods , Lab-On-A-Chip Devices , Microfluidics/methods , Microfluidics/instrumentation
17.
Environ Sci Technol ; 58(24): 10664-10674, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38850427

ABSTRACT

New particle formation (NPF) is a major source of atmospheric aerosol particles, including cloud condensation nuclei (CCN), by number globally. Previous research has highlighted that NPF is less frequent but more intense at roadsides compared to urban background. Here, we closely examine NPF at both background and roadside sites in urban Central Europe. We show that the concentration of oxygenated organic molecules (OOMs) is greater at the roadside, and the condensation of OOMs along with sulfuric acid onto new particles is sufficient to explain the growth at both sites. We identify a hitherto unreported traffic-related OOM source contributing 29% and 16% to total OOMs at the roadside and background, respectively. Critically, this hitherto undiscovered OOM source is an essential component of urban NPF. Without their contribution to growth rates and the subsequent enhancements to particle survival, the number of >50 nm particles produced by NPF would be reduced by a factor of 21 at the roadside site. Reductions to hydrocarbon emissions from road traffic may thereby reduce particle numbers and CCN counts.


Subject(s)
Particulate Matter , Vehicle Emissions , Air Pollutants , Environmental Monitoring , Particle Size , Aerosols
18.
BMC Public Health ; 24(1): 1495, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38835007

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) carries a high public health burden yet little is known about the relationship between metalworking fluid (MWF) aerosols, occupational noise and CKD. We aimed to explore the relationship between occupational MWF aerosols, occupational noise and CKD. METHODS: A total of 2,738 machinists were sampled from three machining companies in Wuxi, China, in 2022. We used the National Institute for Occupational Safety and Health (NIOSH) method 5524 to collect individual samples for MWF aerosols exposure, and the Chinese national standard (GBZ/T 189.8-2007) method to test individual occupational noise exposure. The diagnostic criteria for CKD were urinary albumin/creatinine ratio (UACR) of ≥ 30 mg/g and reduced renal function (eGFR < 60 mL.min- 1. 1.73 m- 2) lasting longer than 3 months. Smooth curve fitting was conducted to analyze the associations of MWF aerosols and occupational noise with CKD. A segmented regression model was used to analyze the threshold effects. RESULTS: Workers exposed to MWF aerosols (odds ratio [OR] = 2.03, 95% confidence interval [CI]: 1.21-3.41) and occupational noise (OR = 1.77, 95%CI: 1.06-2.96) had higher prevalence of CKD than nonexposed workers. A nonlinear and positive association was found between increasing MWF aerosols and occupational noise dose and the risk of CKD. When daily cumulative exposure dose of MWF aerosols exceeded 8.03 mg/m3, the OR was 1.24 (95%CI: 1.03-1.58), and when occupational noise exceeded 87.22 dB(A), the OR was 1.16 (95%CI: 1.04-1.20). In the interactive analysis between MWF aerosols and occupational noise, the workers exposed to both MWF aerosols (cumulative exposure ≥ 8.03 mg/m3-day) and occupational noise (LEX,8 h ≥ 87.22 dB(A)) had an increased prevalence of CKD (OR = 2.71, 95%CI: 1.48-4.96). MWF aerosols and occupational noise had a positive interaction in prevalence of CKD. CONCLUSIONS: Occupational MWF aerosols and noise were positively and nonlinearly associated with CKD, and cumulative MWF aerosols and noise exposure showed a positive interaction with CKD. These findings emphasize the importance of assessing kidney function of workers exposed to MWF aerosols and occupational noise. Prospective and longitudinal cohort studies are necessary to elucidate the causality of these associations.


Subject(s)
Aerosols , Metallurgy , Noise, Occupational , Occupational Exposure , Renal Insufficiency, Chronic , Humans , China/epidemiology , Cross-Sectional Studies , Aerosols/analysis , Aerosols/adverse effects , Noise, Occupational/adverse effects , Occupational Exposure/adverse effects , Occupational Exposure/analysis , Male , Adult , Renal Insufficiency, Chronic/epidemiology , Middle Aged , Female , Air Pollutants, Occupational/analysis , Air Pollutants, Occupational/adverse effects
19.
Environ Sci Technol ; 58(26): 11554-11567, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38885439

ABSTRACT

Understanding of nitrous acid (HONO) production is crucial to photochemical studies, especially in polluted environments like eastern China. In-situ measurements of gaseous and particulate compositions were conducted at a rural coastal site during the 2018 spring Ozone Photochemistry and Export from China Experiment (OPECE). This data set was applied to investigate the recycling of reactive nitrogen through daytime heterogeneous HONO production. Although HONO levels increase during agricultural burning, analysis of the observation data does not indicate more efficient HONO production by agricultural burning aerosols than other anthropogenic aerosols. Box and 1-D modeling analyses reveal the intrinsic relationships between nitrogen dioxide (NO2), particulate nitrate (pNO3), and nitric acid (HNO3), resulting in comparable agreement between observed and simulated HONO concentrations with any one of the three heterogeneous HONO production mechanisms, photosensitized NO2 conversion on aerosols, photolysis of pNO3, and conversion from HNO3. This finding underscores the uncertainties in the mechanistic understanding and quantitative parametrizations of daytime heterogeneous HONO production pathways. Furthermore, the implications for reactive nitrogen recycling, ozone (O3) production, and O3 control strategies vary greatly depending on the HONO production mechanism. On a regional scale, the conversion of HONO from pNO3 can drastically enhance O3 production, while the conversion from NO2 can reduce O3 sensitivity to NOx changes in polluted eastern China.


Subject(s)
Nitrous Acid , Ozone , China , Nitrogen , Air Pollutants , Aerosols , Nitrogen Dioxide
20.
Anal Chem ; 96(26): 10648-10653, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38896456

ABSTRACT

Fentanyl is an extremely potent opioid that is commonly laced into other drugs. Fentanyl poses a danger to users but also to responders or bystanders who may unknowingly ingest a lethal dose (∼2 mg) of fentanyl from aerosolized powder or vapor. Electrochemistry offers a small, simple, and affordable platform for the direct detection of illicit substances; however, it is largely limited to solution-phase measurements. Here, we demonstrate the hands-free capture and electroanalyzation of aerosols containing fentanyl. A novel electrochemical cell is constructed by a microwire (cylindrical working electrode) traversing an ionic liquid film that is suspended within a conductive loop (reference/counter electrode). We provide a quantitative finite element simulation of the resulting electrochemical system. The suspended film maintains a high-surface area:volume, allowing the electrochemical cell to act as an effective aerosol collector. The low vapor pressure (negligible evaporation) of ionic liquid makes it a robust candidate for in-field applications, and the use of a hydrophobic ionic liquid allows for the extraction of fentanyl from solids and sprayed aqueous aerosols.


Subject(s)
Aerosols , Electrochemical Techniques , Fentanyl , Fentanyl/analysis , Aerosols/chemistry , Aerosols/analysis , Ionic Liquids/chemistry , Electrodes , Analgesics, Opioid/analysis
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