Atmospheric mercury in a developed region of eastern China: Interannual variation and gas-particle partitioning.

Atmospheric mercury plays a crucial role in the biogeochemical cycle of mercury. This study conducted an intensive measurement of atmospheric mercury from 2015 to 2018 at a regional site in eastern China. During this period, the concentration of particle-bound mercury (PBM) decreased by 13%, which was much lower than those of gaseous elemenral mercury (GEM, 30%) and reactive gaseous mercury (GOM, 62%).

Atmospheric saccharides over the East China Sea: Assessment of the contribution of sea-land emission and the aging of levoglucosan.

A one-year observation of aerosols on a remote island was conducted and saccharides were applied to reveal the behaviors of organic aerosol in the East China Sea (ECS). The seasonal fluctuations of total saccharides were relatively small, with annual mean concentration of 64.82 ± 26.

Relationship between light absorption properties of black carbon and aerosol origin at a background coastal site.

As a potent climate forcer, black carbon (BC) optical properties can have significant impacts on the regional meteorology and climate. To unveil the seasonal differences of BC and its contribution by various emission sources, a one-year continuous monitoring of atmospheric aerosols was conducted at a background coastal site in Eastern China. By comparing the seasonal and diurnal patterns between BC and elemental carbon, we observed that BC were evidently aged with varying extents among all four seasons.

Seasonal source identification and formation processes of marine particulate water soluble organic nitrogen over an offshore island in the East China Sea.

Water soluble organic nitrogen (WSON) had great influences on the aerosol chemistry, hygroscopicity, marine primary productivity, as well as nitrogen biogeochemical cycles. Aerosol sampling was conducted over an offshore island in the East China Sea in four seasons of 2019, aiming to reveal the seasonal sources and secondary formation processes of marine WSON. The annual mean WSON concentration reached 1.

Response of PM-bound elemental species to emission variations and associated health risk assessment during the COVID-19 pandemic in a coastal megacity.

The coronavirus (COVID-19) pandemic is disrupting the world from many aspects. In this study, the impact of emission variations on PM-bound elemental species and health risks associated to inhalation exposure has been analyzed based on real-time measurements at a remote coastal site in Shanghai during the pandemic. Most trace elemental species decreased significantly and displayed almost no diel peaks during the lockdown.

Effects of rosmarinic acid on the inflammatory response in allergic rhinitis rat models after PM2.5 exposure.

Background: Studies have shown the promising prospects of rosmarinic acid (RosA) for the prevention and treatment of allergic diseases.

Objective: The aim of this study was to investigate the effects of RosA on inflammatory reaction in rat models of allergic rhinitis (AR) after PM2.5 exposure.

Airborne black carbon variations during the COVID-19 lockdown in the Yangtze River Delta megacities suggest actions to curb global warming.

Unlabelled: Airborne black carbon is a strong warming component of the atmosphere. Therefore, curbing black carbon emissions should slow down global warming. The 2019 coronavirus pandemic (COVID-19) is a unique opportunity for studying the response of black carbon to the varied human activities, in particular due to lockdown policies.

Effects of N-acetylcysteine on oxidative stress and inflammation reactions in a rat model of allergic rhinitis after PM exposure.

Particulate matter 2.5 (PM) exposure can increase the prevalence of allergic rhinitis (AR), the mechanism underlying which may include oxidative stress and inflammatory response. As a ROS quenching agent, N-acetylcysteine (NAC) can attenuate the accumulation of inflammatory cells and hyper-responsiveness in animal asthma models.

Ursolic Acid Alleviates Mucus Secretion and Tissue Remodeling in Rat Model of Allergic Rhinitis After PM2.5 Exposure.

Background: According to recent epidemiologic studies, exposure to fine particulate matter (particulate matter 2.5 ≤ µm [PM2.5]) in the air increases the incidence and severity of allergic rhinitis (AR).

Effects of Ursolic Acid on the Expression of Th1-Th2-related Cytokines in a Rat Model of Allergic Rhinitis After PM2.5 Exposure.

Background: Allergic rhinitis (AR) is a global health problem and closely related to environmental factors. Ursolic acid (UA) has potential in the treatment of allergic inflammation. The effects of UA intervention on PM2.

Effect of PM2.5 on MicroRNA Expression and Function in Nasal Mucosa of Rats With Allergic Rhinitis.

Background: Particulate matter 2.5 (PM2.5) refers to particulate matter with aerodynamic equivalent diameter less than or equal to 2.

Assessing Contributions of Agricultural and Nonagricultural Emissions to Atmospheric Ammonia in a Chinese Megacity.

Ammonia (NH) is the predominant alkaline gas in the atmosphere contributing to formation of fine particles-a leading environmental cause of increased morbidity and mortality worldwide. Prior findings suggest that NH in the urban atmosphere derives from a complex mixture of agricultural (mainly livestock production and fertilizer application) and nonagricultural (e.g.

Development and validation of a HPLC/FLD method combined with online derivatization for the simple and simultaneous determination of trace amino acids and alkyl amines in continental and marine aerosols.

A method was developed for simultaneous determination of 15 amino acids and 7 alkyl amines. The method was based on the employment of high performance liquid chromatography/fluorescence detection and online derivatization with o-phthaldiadehyde. The 22 derivatives were separated within 30 min including the equilibration time and detected by a fluorescence detector at an excitation wavelength of 230 nm and emission wavelength of 450 nm.

Characteristics of particulate-bound mercury at typical sites situated on dust transport paths in China.

The concentrations and seasonal variations of PBM (particulate-bound mercury) were observed at four dust source sites (Duolun, Yulin, Hetian, and Tazhong), two megacities (Shanghai and Beijing), and an island site (Huaniao Island) to obtain the spatiotemporal characteristics of PBM in dust transport path from desert area in China to the East China Sea. The highest annual mean concentrations of PBM in TSP (PBM) were observed at megacity sites, reaching 146.7 pg/m and 274.

Effects of PM2.5 on mucus secretion and tissue remodeling in a rabbit model of chronic rhinosinusitis.

Background: According to epidemiologic studies, fine particulate matter (particulate matter ≤2.5 μm, PM2.5) is closely associated with increases in the incidence and severity of chronic rhinosinusitis (CRS).

Determination of atmospheric alkylamines by ion chromatography using 18-crown-6 as mobile phase additive.

An improved ion chromatographic method including two elution procedures was proposed for the quantitative determination of atmospheric alkylamines in field atmospheric samples involving high levels of inorganic cations by using 18-crown-6 as mobile phase additive. When 18-crown-6 was added to the mobile phase, the retention times increased significantly for Na, NH, K and primary alkylamines but decreased for secondary and tertiary alkylamines due to the complexation with certain cations and interaction with both stationary and mobile phases of 18-crown-6. As a result, the separation of the cations was greatly promoted, which reduced the interference of peak distortion of overloaded inorganic cations on the quantitation of adjacent alkylamines.

First long-term detection of paleo-oceanic signature of dust aerosol at the southern marginal area of the Taklimakan Desert.

We firstly conducted a long-term in-situ field measurement at a marginal area (Hotan) of the southern Taklimakan Desert covering all four seasons. Detailed chemical characterization of dust aerosol over Hotan showed several unconventional features, including (1) ubiquity of high Na and Cl abundances in the Taklimakan dust aerosol and its Cl/Na ratio close to seawater; (2) high Ca content in the Taklimakan dust (7.4~8.

Nasal epithelial barrier disruption by particulate matter ≤2.5 μm via tight junction protein degradation.

Upper airway diseases including sinonasal disorders may be caused by exposure to fine particulate matter (≤2.5 μm; PM2.5), as proven by epidemiological studies.

Insights into the characteristics and sources of primary and secondary organic carbon: High time resolution observation in urban Shanghai.

There is growing evidence suggesting that organic aerosols play an important role in the evolution of severe haze episodes. However, long-term investigations of the different characteristics of carbonaceous aerosols during haze and non-haze days are insufficient. In this work, hourly measurements of organic carbon (OC) and elemental carbon (EC) in PM were conducted in Shanghai, a megacity in Eastern China, over the course of a year from July 2013 to June 2014.

Signal Transductions of BEAS-2B Cells in Response to Carcinogenic PM Exposure Based on a Microfluidic System.

PM (particulate matter less than 2.5 μm in diameter) is considered as a harmful carcinogen. Determining the precise relationship between the chemical constituents of PM in the air and cancer progression could aid the treatment of environment related disease and establishing risk reduction strategies.

T-helper type 1-T-helper type 2 shift and nasal remodeling after fine particulate matter exposure in a rat model of allergic rhinitis.

Background: Exposure to fine particulate matter (particulate matter ≤2.5 μm [PM2.5]) increases the risk of allergic rhinitis (AR), but the underlying mechanisms remains unclear.

PM-Induced Oxidative Stress and Mitochondrial Damage in the Nasal Mucosa of Rats.

Exposure to PM (particulate matter ≤2.5 μm) increases the risk of nasal lesions, but the underlying mechanisms, especially the mechanisms leading to mitochondrial damage, are still unclear. Thus, we investigated the in vivo effects of PM exposure on the inflammatory response, oxidative stress, the enzyme activities of Na⁺K⁺-ATPase and Ca-ATPase, and the morphology and function of mitochondria in the nasal mucosa of rats.

Quantitative analysis of aliphatic amines in urban aerosols based on online derivatization and high performance liquid chromatography.

A method combining online derivatization with high performance liquid chromatography/fluorescence detection was developed for the determination of seven aliphatic amines (ethanolamine, methylamine, ethylamine, propylamine, butylamine, pentylamine and hexylamine) in urban aerosols. The collected amines were online derivatized with o-phthalaldehyde to form highly fluorescent sulfonatoisoindole derivatives. The derivatives were completely separated in 13 min through gradient elution and detected by fluorescence detection at an excitation wavelength of 334 nm and an emission wavelength of 443 nm.

Airborne Fine Particulate Matter Induces Oxidative Stress and Inflammation in Human Nasal Epithelial Cells.

Airborne fine particulate matter with an aerodynamic diameter equal to or smaller than 2.5 μm is abbreviated as PM2.5, which is one of the main components in air pollution.

Human Excreta as a Stable and Important Source of Atmospheric Ammonia in the Megacity of Shanghai.

Although human excreta as a NH3 source has been recognized globally, this source has never been quantitatively determined in cities, hampering efforts to fully assess the causes of urban air pollution. In the present study, the exhausts of 15 ceiling ducts from collecting septic tanks in 13 buildings with 6 function types were selected to quantify NH3 emission rates in the megacity of Shanghai. As a comparison, the ambient NH3 concentrations across Shanghai were also measured at 13 atmospheric monitoring sites.