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1.
Chemosphere ; 254: 126863, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957281

RESUMO

In urban set up, increasing combustion and processing activities have contaminated the air with toxic heavy metals which are generally enriched on atmospheric particulate matter. Vegetation around urban area act as a sink where such metal enriched particles generally deposit on the foliar surfaces, however, role of vegetation in uptake of metals adhered on the atmospheric particulate matter is yet not explored properly and is important to study to evaluate their role as bio-remediator. The undertaken work examines the foliar surface of Morus alba for its potential to deposit and accumulate atmospheric heavy metals. Further, to understand foliar uptake mechanism and translocation of atmospheric metal enriched on particulate matter a simulated experiment was conducted by labeling the known particle size (45 µm and 120 µm) with radio labeled 65Zn, applied on the tagged leaf with two particle loads, 25 mg and 50 mg. The study showed that owing to its rough foliar surface with trichomes and grooves, Morus alba efficiently trap heavy metal enriched particles and was capable of accumulating metals from particulate matter into different plant parts. It was recorded that 65Zn adhered on different size particles was taken up by tagged leaf of mulberry and majorly translocated to the lower stem and roots. It was also inferred from the study that both particle size and particle load significantly affect the foliar uptake and translocation of atmospheric heavy metal. The study focuses on the fact that urban avenue trees are capable of taking up atmospheric heavy metals and can play a crucial role in improving air quality.


Assuntos
Poluentes Atmosféricos/metabolismo , Morus/metabolismo , Material Particulado/farmacocinética , Zinco/farmacocinética , Poluentes Atmosféricos/farmacocinética , Poluição do Ar , Biodegradação Ambiental , Tamanho da Partícula , Material Particulado/análise , Material Particulado/química , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Traçadores Radioativos , Radioisótopos de Zinco/farmacocinética
2.
Chemosphere ; 261: 127758, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32736246

RESUMO

Cooking emissions are both indoor and outdoor sources for fine particulate matter (PM2.5) but their contributions are often ignored. The PM2.5-bound organic compounds, including alkanols, alkanes, monocarboxylic acids, dicarboxylic acids, and polycyclic aromatic hydrocarbons (PAHs) were determined in the emissions from the most popular types of restaurants in the capital city of northwestern China. The mean concentration of total quantified organic compounds (ΣPM_O) ranged from 1112 to 32,016 ng m-3, with the maximum for the Chinese barbecue restaurants. The ΣPM_O accounted for an average of 11% of PM2.5 mass, demonstrating their significances in the cooking emissions. Hexadecanoic acid (C16) and 1-hexadecanol (C16) were considered as the tracers for stir-frying, steaming, and boiling which are usually applied in the traditional Chinese cuisines; 1-undecanol (C11), 9-fluorenone, and indeno[1,2,3-cd]pyrene were found to be potential markers for grilling and deep-frying which are widely applied in the Western style cooking method. The PAH diagnostic ratios also illustrated their representatives to distinguish the emissions from traditional Chinese cuisines and the Western-style restaurants. The estimated carcinogenic risks for the restaurants that consumed a large amount of oils and employed high temperature cooking methods (e.g., barbecuing and deep-frying) were 2.6-4.2 times exceeded the international safety limit. The organic profiles obtained in this study could be contributed to refine PM2.5 source apportionment in urban areas in northwestern China. The estimations of potential cancer risks urge the establishment of more stringent legislations to protect the health of the catering staffs.


Assuntos
Poluentes Atmosféricos/análise , Culinária , Monitoramento Ambiental/métodos , Neoplasias/epidemiologia , Compostos Orgânicos/análise , Material Particulado/análise , Poluentes Atmosféricos/química , China , Cidades , Culinária/métodos , Humanos , Neoplasias/induzido quimicamente , Compostos Orgânicos/química , Material Particulado/química , Restaurantes , Medição de Risco
3.
Chemosphere ; 261: 127750, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32712379

RESUMO

This study focused on particulate matter (PM2.5) and carbon species in Seoul, South Korea, to quantitatively evaluate their long-term trends and assess the main correlating factors. Ambient PM2.5 samples were collected over a 24 h period every third or sixth day from March 2003 to December 2017. The mean concentrations of PM2.5, organic carbon (OC), elemental carbon (EC), primary and secondary OC (POC and SOC) in Seoul over 15 years were 32.2 µg/m3 and 7.28 µg/m3, 1.85 µg/m3, 4.29 µg/m3 and 3.54 µg/m3 respectively. The long-term concentration trends in PM2.5, OC, EC, POC, and SOC decreased significantly at rates of -2.09, -3.13, -6.31, -2.86, and -3.88 per year, respectively from 2003 to 2017 (p < 0.001), whereas the long-term trends in OC/EC significantly increased at a rate of 12.9/year (p < 0.001). These long-term decreases in PM2.5 and carbon species concentrations were most pronounced in 2008 but almost disappeared from 2013 onwards. Considering the decrease in wind speed and variations in the concentration of gaseous air pollutants (carbon monoxide, sulfur dioxide, nitrogen dioxide, and volatile organic compounds) without a tendency to increase or decrease since 2013, secondary aerosol formation by atmospheric stagnation alleviated long-term decreases in PM2.5 and carbon species concentrations. The long-term decreases in EC concentration were the most consistent and rapid, strongly suggesting that atmospheric policies related to mobile in South Korea were effective in reducing EC concentration. Future air quality management should focus on the secondary formation of air pollutants based on regional trends in air pollutant concentrations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Aerossóis , Poluentes Atmosféricos/química , Carbono/química , Material Particulado/química , República da Coreia , Estações do Ano , Seul , Dióxido de Enxofre , Fatores de Tempo , Vento
4.
PLoS One ; 15(7): e0236479, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716950

RESUMO

BACKGROUND: Many studies have identified an inequitable distribution of exposure to PM2.5 (particulate matter less than 2.5 microns) by race. We investigated the association of PM2.5 and cardiovascular mortality considering both the decedents' race and neighborhood racial composition as potential modifiers. METHODS: We obtained geocoded cardiovascular mortality records of all black and white decedents from urban block-groups in Massachusetts between 2001 and 2011 (n = 130,863). We examined the association between PM2.5 and cardiovascular mortality, and assessed effect modification by three types of racial modifiers: decedents' race, census block-group percent black and white, and two novel measures of racial segregation. The Racial Residential Segregation (RRS) quantifies the concentration of non-Hispanic blacks and whites in each block-group. The Index of Racial Dissimilarity measures dissimilarity in non-Hispanic black and white racial distribution between the smaller census block-group and larger tract. RESULTS: We found a 2.35%(95%CI: 0.92%;3.79%) increase in mortality for each 10µg/m3 increase in two-day average exposure to PM2.5. The effect was modified by the block-group racial composition, with higher risks in block-groups with the highest percentage of black residents (interaction p-value = 0.04), and in block-groups with the lowest RRS (i.e. higher black to white resident ratio, interaction p-value = 0.072). Racial dissimilarity did not modify the associations. CONCLUSION: Current levels of PM2.5 are associated with increased cardiovascular deaths in Massachusetts, with different risks between areas with different racial composition and segregation. This suggests that pollution reductions in neighborhoods with the highest percentage of non-Hispanic blacks would be most beneficial in reducing cardiovascular mortality and disparities.


Assuntos
Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/mortalidade , Grupos de Populações Continentais , Tamanho da Partícula , Material Particulado/efeitos adversos , Material Particulado/química , Segregação Social , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Fatores de Risco , Estatística como Assunto , População Urbana
5.
J Vis Exp ; (159)2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32510496

RESUMO

The current particle size threshold of the European Particle Number (PN) emission standards is 23 nm. This threshold could change because future combustion engine vehicle technology may emit large amounts of sub-23 nm particles. The Horizon 2020 funded project DownToTen (DTT) developed a sampling and measurement method to characterize particle emissions in this currently unregulated size range. A PN measurement system was developed based on an extensive review of the literature and laboratory experiments testing a variety of PN measurement and sampling approaches. The measurement system developed is characterized by high particle penetration and versatility, which enables the assessment of primary particles, delayed primary particles, and secondary aerosols, starting from a few nanometers in diameter. This paper provides instruction on how to install and operate this Portable Emission Measurement System (PEMS) for Real Drive Emissions (RDE) measurements and assess particle number emissions below the current legislative limit of 23 nm.


Assuntos
Condução de Veículo , Monitoramento Ambiental/métodos , Nanopartículas/análise , Nanopartículas/química , Tamanho da Partícula , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/química , Monitoramento Ambiental/instrumentação , Laboratórios , Material Particulado/análise , Material Particulado/química
6.
Ecotoxicol Environ Saf ; 201: 110827, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32535366

RESUMO

Numerous experimental and epidemiological studies have demonstrated that exposure to PM2.5 may result in pathogenesis of several major cardiovascular diseases (CVDs), which can be attributed to the combined adverse effects induced by the complicated components of PM2.5. Organic materials, which are major components of PM2.5, contain thousands of chemicals, and most of them are environmental hazards. However, the contamination profile and contribution to overall toxicity of PM2.5-bound organic components (OCs) have not been thoroughly evaluated yet. Herein, we aim to provide an overview of the literature on PM2.5-bound hydrophobic OCs, with an emphasis on the chemical identity and reported impairments on the cardiovascular system, including the potential exposure routes and mechanisms. We first provide an update on the worldwide mass concentration and composition data of PM2.5, and then, review the contamination profile of PM2.5-bound hydrophobic OCs, including constitution, concentration, distribution, formation, source, and identification. In particular, the link between exposure to PM2.5-bound hydrophobic OCs and CVDs and its possible underlying mechanisms are discussed to evaluate the possible risks of PM2.5-bound hydrophobic OCs on the cardiovascular system and to provide suggestions for future studies.


Assuntos
Poluentes Atmosféricos/toxicidade , Doenças Cardiovasculares/induzido quimicamente , Sistema Cardiovascular/efeitos dos fármacos , Monitoramento Ambiental/métodos , Compostos Orgânicos/toxicidade , Material Particulado/toxicidade , Poluentes Atmosféricos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Compostos Orgânicos/química , Material Particulado/química
7.
Ecotoxicol Environ Saf ; 201: 110726, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32480160

RESUMO

BACKGROUND: Impaired in utero fetal growth trajectory may have long term health consequences of the newborns and increase risk of adulthood metabolic diseases. Prenatal exposure to air pollution has been linked to fetal development restriction; however, the impact of exposure to ambient air pollutants on the entire course of intrauterine fetal development has not been comprehensively investigated. METHODS: During 2015-2018, two cohorts of mother-infant dyads (N = 678 and 227) were recruited in Shanghai China, from which three categories of data were systematically collected: (1) daily exposure to six air pollutants during pregnancy, (2) fetal biometry in the 2nd (gestational week 24, [GW24]) and 3rd trimester (GW36), and (3) neonatal outcomes at birth. We investigated the impact of prenatal exposure to air pollutant mixture on the trajectory of fetal development during the course of gestation, adjusting for a broad set of potential confounds. RESULTS: Prenatal exposure to PM2.5, PM10, SO2 and O3 significantly reduced fetal biometry at GW24, where SO2 had the most potent effect. For every 10 µg/m3 increment increase of daily SO2 exposure during the 1st trimester shortened femur length by 2.20 mm (p = 6.7E-21) translating to 5.3% reduction from the average of the study cohort. Prenatal air pollution exposure also decreased fetal biometry at GW36 with attenuated effect size. Comparing to the lowest exposed quartile, fetus in the highest exposed quartile had 6.3% (p = 3.5E-5) and 2.1% (p = 2.4E-3) lower estimated intrauterine weight in GW24 and GW36, respectively; however, no difference in birth weight was observed, indicating a rapid catch-up growth in the 3rd trimester. CONCLUSIONS: To our knowledge, for the first time, we demonstrated the impact of prenatal exposure to ambient air pollutants on the course of intrauterine fetal development. The altered growth trajectory and rapid catch-up growth in associated with high prenatal exposure may lead to long-term predisposition for adulthood metabolic disorders.


Assuntos
Poluentes Atmosféricos/toxicidade , Desenvolvimento Fetal/efeitos dos fármacos , Exposição Materna/efeitos adversos , Material Particulado/toxicidade , Adulto , Poluentes Atmosféricos/química , China/epidemiologia , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Material Particulado/química , Gravidez
8.
Nat Commun ; 11(1): 2800, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: covidwho-419772

RESUMO

Understanding the particle size distribution in the air and patterns of environmental contamination of SARS-CoV-2 is essential for infection prevention policies. Here we screen surface and air samples from hospital rooms of COVID-19 patients for SARS-CoV-2 RNA. Environmental sampling is conducted in three airborne infection isolation rooms (AIIRs) in the ICU and 27 AIIRs in the general ward. 245 surface samples are collected. 56.7% of rooms have at least one environmental surface contaminated. High touch surface contamination is shown in ten (66.7%) out of 15 patients in the first week of illness, and three (20%) beyond the first week of illness (p = 0.01, χ2 test). Air sampling is performed in three of the 27 AIIRs in the general ward, and detects SARS-CoV-2 PCR-positive particles of sizes >4 µm and 1-4 µm in two rooms, despite these rooms having 12 air changes per hour. This warrants further study of the airborne transmission potential of SARS-CoV-2.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Microbiologia Ambiental , Quartos de Pacientes , Pneumonia Viral/virologia , Adulto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/transmissão , Estudos Transversais , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Tamanho da Partícula , Material Particulado/análise , Material Particulado/química , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , Pneumonia Viral/transmissão , Fatores de Tempo
9.
Chemosphere ; 251: 126598, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443236

RESUMO

Here we present a long-term, hourly resolution dataset (from January 2014 to April 2015) of secondary inorganic aerosol (SIA) matter, organic matter (OM) and black carbon (BC) as PM2.5 chemical components in China. Seasonally differentiated weekly diurnal profiles of major particulate species were investigated in conjunction with potential source contribution function (PSCF) analysis. The average concentration of PM2.5 was 48.3 ± 35.1 µg m-3, in which OM was the major constituent (29.7 ± 13.9%), followed by sulfate (25.1 ± 8.1%), nitrate (18.5 ± 8.3%), ammonium (13.3 ± 3.8%), and other trace species (6.8 ± 4.0%). Interestingly, unlike other PM species, OM concentrations kept very similar level among different seasons, indicating on-road traffic is a stable source of PM2.5. Besides, a persistently strong particulate OM pollution belt was found along the lower reaches of Yangtze River. Significant enhancement of SIA (mainly nitrate) was coincided with high PM2.5 mass loading. Source apportionment were conducted and found the overwhelming dominance of long-range transport of the pollutants from north China. Using a case study, we further integrate Weather Research and Forecasting (WRF) meteorological modeling and lidar observation to better understand the evolution process of a typical pollution episode. Our assessment of the extremely large datasets derived from Shanghai supersite demonstrated the online instrumentation as a robust and credible alternative to filter-based sampling techniques for long-term PM2.5 monitoring and characterization in heavily polluted areas.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/química , Monitoramento Ambiental/métodos , Material Particulado/análise , Material Particulado/química , Aerossóis , China , Cidades , Carvão Mineral/análise , Nitratos/análise , Óxidos de Nitrogênio/análise , Rios/química , Estações do Ano , Sulfatos/análise , Tempo (Meteorologia)
10.
Ecotoxicol Environ Saf ; 199: 110686, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32408034

RESUMO

Limited studies have been conducted to evaluate the short-term relationships between exposure to coarse particulate matter (PM2.5-10) and outpatient visits in China. We designed this time-series analysis in a Chinese city Yancheng, to explore the relationship of PM2.5-10 with outpatient visits for cardiopulmonary diseases. The study period was from 2013 to 2015. A typical generalized additive model was used. We explored the lag patterns by building a series of lag of exposure. We also built two-pollutant models to ascertain the independence of PM2.5-10. Stratified analyses were applied to compare the season-specific associations. Finally, we pooled the concentration-response (C-R) curves for PM2.5-10 and outpatient visits. We recorded a daily average of 85 and 43 outpatient visits for cardiovascular and respiratory causes, respectively. PM2.5-10 exposures of lag 05 day yielded the best estimates for both outcomes. Per 10-µg/m3 increase in PM2.5-10, there was a 1.69% (95% confidence interval [CI]: 0.68%-2.72%) increase in outpatient visits for respiratory causes, and a 0.85% (95% CI: 0.13%-1.57%) increase for cardiovascular causes. The association kept robust after adjusting for PM2.5 and O3, and there were larger associations in warm seasons. The C-R curves had a larger slope for respiratory diseases in relatively lower concentrations (<30 µg/m3), and PM2.5-10 was positively associated with cardiovascular diseases in higher concentrations (>30 µg/m3). This study indicated significant associations of PM2.5-10 with cardiopulmonary outpatient visit. Such results may be used for health risk assessment and policy making for particulate air pollution control.


Assuntos
Poluentes Atmosféricos/análise , Assistência Ambulatorial/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Material Particulado/análise , Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , China , Cidades , Humanos , Pacientes Ambulatoriais , Material Particulado/química , Material Particulado/toxicidade , Medição de Risco , Estações do Ano
11.
Nat Commun ; 11(1): 2800, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472043

RESUMO

Understanding the particle size distribution in the air and patterns of environmental contamination of SARS-CoV-2 is essential for infection prevention policies. Here we screen surface and air samples from hospital rooms of COVID-19 patients for SARS-CoV-2 RNA. Environmental sampling is conducted in three airborne infection isolation rooms (AIIRs) in the ICU and 27 AIIRs in the general ward. 245 surface samples are collected. 56.7% of rooms have at least one environmental surface contaminated. High touch surface contamination is shown in ten (66.7%) out of 15 patients in the first week of illness, and three (20%) beyond the first week of illness (p = 0.01, χ2 test). Air sampling is performed in three of the 27 AIIRs in the general ward, and detects SARS-CoV-2 PCR-positive particles of sizes >4 µm and 1-4 µm in two rooms, despite these rooms having 12 air changes per hour. This warrants further study of the airborne transmission potential of SARS-CoV-2.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Microbiologia Ambiental , Quartos de Pacientes , Pneumonia Viral/virologia , Adulto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/transmissão , Estudos Transversais , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Tamanho da Partícula , Material Particulado/análise , Material Particulado/química , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , Pneumonia Viral/transmissão , Fatores de Tempo
12.
J Environ Public Health ; 2020: 1561823, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351580

RESUMO

Particulate matter with an aerodynamic diameter of 10 µm or less (PM10) pollution poses a considerable threat to human health, and the first step in quantifying health impacts of human exposure to PM10 pollution is exposure assessment. Population-weighted exposure level (PWEL) estimation is one of the methods that provide a more refined exposure assessment as it includes the spatiotemporal distribution of the population into the pollution concentration estimation. This study assessed the population weighting effects on the estimated PM10 concentrations in Malaysia for years 2000, 2008, and 2013. Estimated PM10 annual mean concentrations with a spatial resolution of 5 kilometres retrieved from satellite data and population count obtained from the Gridded Population of the World version 4 (GPWv4) from the Centre for International Earth Science Information Network (CIESIN) were overlaid to generate the PWEL of PM10 for each state. The calculated PWEL of PM10 concentrations were then classified based on the World Health Organization (WHO) and the national Air Quality Guidelines (AQG) and interim targets (IT) for comparison. Results revealed that the annual mean PM10 concentrations in Malaysia ranged from 31 to 73 µg/m3 but became generally lower, ranging from 20 to 72 µg/m3 after population weighting, suggesting that the PM10 population exposure in Malaysia might have been overestimated. PWEL of PM10 distribution showed that the majority of the population lived in areas that complied with the national AQG, but were vulnerable to exposure level 3 according to the WHO AQG and IT, indicating that the population was nevertheless potentially exposed to significant health effects from long-term exposure to PM10 pollution.


Assuntos
Poluentes Atmosféricos/análise , Exposição por Inalação/análise , Material Particulado/análise , Poluição do Ar/análise , Monitoramento Ambiental , Humanos , Exposição por Inalação/normas , Malásia , Tamanho da Partícula , Material Particulado/química , Análise Espaço-Temporal
13.
Nat Commun ; 11(1): 2567, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444803

RESUMO

Ambient particulate matter pollution is one of the leading causes of global disease burden. Epidemiological studies have revealed the connections between particulate exposure and cardiovascular and respiratory diseases. However, until now, the real species of ambient ultrafine particles (UFPs) in humans are still scarcely known. Here we report the discovery and characterization of exogenous nanoparticles (NPs) in human serum and pleural effusion (PE) samples collected from non-occupational subjects in a typical polluted region. We show the wide presence of NPs in human serum and PE samples with extreme diversity in chemical species, concentration, and morphology. Through chemical multi-fingerprinting (including elemental fingerprints, high-resolution structural fingerprints, and stable iron isotopic fingerprints) of NPs, we identify the sources of the NPs to be abiogenic, particularly, combustion-derived particulate emission. Our results provide evidence for the translocation of ambient UFPs into the human circulatory system, and also provide information for understanding their systemic health effects.


Assuntos
Material Particulado/análise , Material Particulado/química , Derrame Pleural/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Ferro/análise , Pneumopatias/sangue , Pneumopatias/patologia , Masculino , Metais/análise , Camundongos , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Nanopartículas/análise , Nanopartículas/química , Tamanho da Partícula , Material Particulado/sangue , Material Particulado/toxicidade , Células RAW 264.7 , Espectrometria por Raios X
14.
PLoS One ; 15(4): e0230983, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240214

RESUMO

China has the largest share of global iron and steel production, which is considered to play a significant contribution to air pollution. This study aims to investigate trace element contamination at different fractions of particulate matter (PM) at industrial areas in China. Three PM fractions, PM2.1-9.0, PM1.1-2.1 and PM1.1, were collected from areas surrounding iron and steelmaking plants at Kunming, Wuhan, Nanjing and Ningbo in China. Multiple trace elements and their bioavailability, as well as Pb isotopic compositions, were analysed for identification of contaminants, health risk assessment and source apportionment. Results showed that PM particles in the sites near industrial areas were associated with a range of toxic trace elements, specifically As, Cr(VI), Cd and Mn, and posed significant health risks to humans. The isotopic Pb compositions identified that coal and high temperature metallurgical processes in the steelmaking process were the dominant contributors to local air pollution in these sites. In addition to iron and steelmaking activities, traffic emissions and remote pollution also played a contributing role in PM contamination, confirmed by the differences of Pb isotopic compositions at each PM fraction and statistical results from Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) and Geometrical Analysis for Interactive Aid (GAIA). The results presented in this study provide a comprehensive understanding of PM emissions at iron and steelmaking areas, which helps to guide subsequent updates of air pollution control guidelines to efficiently minimise environmental footprint and ensure long term sustainability of the industries.


Assuntos
Poluentes Atmosféricos/análise , Ferro/química , Material Particulado/efeitos adversos , Material Particulado/química , Aço/química , Oligoelementos/efeitos adversos , Oligoelementos/química , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/química , Poluição do Ar/efeitos adversos , China , Carvão Mineral/efeitos adversos , Monitoramento Ambiental/métodos , Feminino , Humanos , Indústrias/métodos , Masculino , Medição de Risco/métodos , Estações do Ano
15.
Environ Pollut ; 261: 114239, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32114124

RESUMO

This study presents a comprehensive analysis of organic carbon (OC), elemental carbon (EC), and particularly the light absorption characteristics of EC and water-soluble brown carbon (WS-BrC) in total suspended particles in the Kathmandu Valley from April 2013 to January 2018. The mean OC, EC, and water-soluble organic carbon (WSOC) concentrations were 34.8 ± 27.1, 9.9 ± 5.8, and 17.4 ± 12.5 µg m-3, respectively. A clear seasonal variation was observed for all carbonaceous components with higher concentrations occurring during colder months and lower concentrations in the monsoon season. The relatively low OC/EC ratio (3.6 ± 2.0) indicates fossil fuel combustion as the primary source of carbonaceous components. The optical attenuation (ATN) at 632 nm was significantly connected with EC loading (ECS) below 15 µg cm-2 but ceased as ECS increased, reflecting the increased influence of the shadowing effect. The derived average mass absorption cross-section of EC (MACEC) (7.0 ± 4.2 m2 g-1) is comparable to that of freshly emitted EC particles, further attesting that EC was mainly produced from local sources with minimal atmospheric aging processes. Relatively intensive coating with organic aerosols and/or salts (e.g., sulfate, nitrate) was probably the reason for the slightly higher MACEC during the monsoon season, whereas increased biomass burning was a major factor leading to lower MACEC in other seasons. The average MACWS-BrC at 365 nm was 1.4 ± 0.3 m2 g-1 with minimal seasonal variations. In contrast to MACEC, biomass burning was the main reason for a higher MACWS-BrC in the non-monsoon season. The relative light absorption contribution of WS-BrC to EC was 9.9% over the 300-700 nm wavelength range, with a slightly higher ratio (13.6%) in the pre-monsoon season. Therefore, both EC and WS-BrC should be considered in the study of optical properties and radiative forcing of carbonaceous aerosols in this region.


Assuntos
Carbono , Monitoramento Ambiental , Luz , Material Particulado , Aerossóis , Biomassa , Carbono/química , Nepal , Material Particulado/química , Estações do Ano , Água/química
16.
Cell Physiol Biochem ; 54(2): 230-251, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32153152

RESUMO

BACKGROUND/AIMS: Adverse effects of cigarette smoke on health are widely known. Heating rather than combusting tobacco is one of strategies to reduce the formation of toxicants. The sensitive nature of mitochondrial dynamics makes the mitochondria an early indicator of cellular stress. For this reason, we studied the morphology and dynamics of the mitochondrial network in human bronchial epithelial cells (BEAS-2B) exposed to total particulate matter (TPM) generated from 3R4F reference cigarette smoke and from aerosol from a new candidate modified risk tobacco product, the Tobacco Heating System (THS 2.2). METHODS: Cells were subjected to short (1 week) and chronic (12 weeks) exposure to a low (7.5 µg/mL) concentration of 3R4F TPM and low (7.5 µg/mL), medium (37.5 µg/mL), and high (150 µg/mL) concentrations of TPM from THS 2.2. Confocal microscopy was applied to assess cellular and mitochondrial morphology. Cytosolic Ca2+ levels, mitochondrial membrane potential and mitochondrial mass were measured with appropriate fluorescent probes on laser scanning cytometer. The levels of proteins regulating mitochondrial dynamics and biogenesis were determined by Western blot. RESULTS: In BEAS-2B cells exposed for one week to the low concentration of 3R4F TPM and the high concentration of THS 2.2 TPM we observed clear changes in cell morphology, mitochondrial network fragmentation, altered levels of mitochondrial fusion and fission proteins and decreased biogenesis markers. Also cellular proliferation was slowed down. Upon chronic exposure (12 weeks) many parameters were affected in the opposite way comparing to short exposure. We observed strong increase of NRF2 protein level, reorganization of mitochondrial network and activation of the mitochondrial biogenesis process. CONCLUSION: Comparison of the effects of TPMs from 3R4F and from THS 2.2 revealed, that similar extent of alterations in mitochondrial dynamics and biogenesis is observed at 7.5 µg/mL of 3R4F TPM and 150 µg/mL of THS 2.2 TPM. 7 days exposure to the investigated components of cigarette smoke evoke mitochondrial stress, while upon chronic, 12 weeks exposure the hallmarks of cellular adaptation to the stressor were visible. The results also suggest that mitochondrial stress signaling is involved in the process of cellular adaptation under conditions of chronic stress caused by 3R4F and high concentration of THS 2.2.


Assuntos
Aerossóis/química , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Material Particulado/toxicidade , Cálcio/metabolismo , Linhagem Celular , Corantes Fluorescentes/química , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Confocal , Mitocôndrias/efeitos dos fármacos , Material Particulado/química , Fumaça/efeitos adversos , Fatores de Tempo , Produtos do Tabaco/análise
17.
Chemosphere ; 250: 126269, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32126330

RESUMO

MSWI(Municipal solid waste incineration) fly ash as hazardous wastes usually is treated properly with OPC(ordinary Portland cement) based binders prior to being disposed in security landfill, but some toxic elements present poor stability in its highly alkaline environment. This study developed a novel solidification/stabilization technology based on MgO-SiO2-H2O (M-S-H) cementious material with compatibility with contaminants for MSWI fly ash encapsulation. Compressive strength and leaching toxicity tests were undertaken to evaluate the immobilization effect of MSWI fly ash treated with M-S-H matrix. And TAM, XRD, DTA/TGA and SEM techniques were employed to explore hydration process and microstructure morphology of M-S-H solidified body. Results demonstrated that M-S-H cement matrix played a positive impact on the immobilization of heavy metals, and the immobilization rate of Cd, Pb and Zn was 97.5%, 99.8% and 98.7%, which was far more than that fixed in Portland cement. The incorporation of MSWI fly ash inhibited the hydration process of M-S-H matrix on the whole, which was mainly due to its poor pozzolanic activity. Moreover, there were some new hydration phases including CdSiO3, Ca3PbSiO6 and Zn(OH)2 generated and some MSWI fly ash embedded in the core-shell structure of M-S-H matrix in depth. These results suggested that heavy metals of MSWI fly ash were mainly fixed in M-S-H solidified bodies by physical encapsulation, isomorphous replacement and chemical precipitation. Overall, this study demonstrated that M-S-H matrix is a promising candidate that can serve as low-carbon and high-efficient materials for hazardous MSWI fly ash.


Assuntos
Incineração , Carbono/química , Força Compressiva , Materiais de Construção , Resíduos Perigosos , Óxido de Magnésio/química , Metais Pesados/análise , Material Particulado/química , Eliminação de Resíduos/métodos , Dióxido de Silício/química , Resíduos Sólidos/análise
18.
Ecotoxicol Environ Saf ; 193: 110368, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32114245

RESUMO

Emerging POPs have received increasing attention due to their potential persistence and toxicity, but thus far the report regarding the occurrence and distribution of these POPs in PM2.5 is limited. In this study, an extremely sensitive and reliable method, using ultrasonic solvent extraction and silica gel purification followed by gas chromatography coupled with electron ionization triple quadrupole mass spectrometry, was developed and used for the trace analysis of hexachlorobutadiene (HCBD), pentachloroanisole (PCA) and its analogs chlorobenzenes (CBs) in PM2.5 from Taiyuan within a whole year. The limits of detection and limits of quantitation of analytes were 1.14 × 10-4‒2.74 × 10-4 pg m-3 and 3.80 × 10-4‒9.14 × 10-4 pg m-3. HCBD and PCA were detected at the mean concentrations of 3.69 and 1.84 pg m-3 in PM2.5, which is reported for the first time. Based on the results of statistical analysis, HCBD may come from the unintentional emission of manufacture or incineration of chlorinate-contained products but not coal combustion, while O3-induced photoreaction was the potential source of PCA in PM2.5. The temporal distributions of CBs in PM2.5 were closely related to coal-driven or agricultural activities. Accordingly, our study reveals the contamination profiles of emerging POPs in PM2.5 from Taiyuan.


Assuntos
Poluentes Atmosféricos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Material Particulado/química , Anisóis/análise , Butadienos/análise , Clorobenzenos/análise , Carvão Mineral , Incineração , Espectrometria de Massas em Tandem/métodos
19.
Proc Jpn Acad Ser B Phys Biol Sci ; 96(3): 122-129, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161210

RESUMO

Black carbon (BC) particles cause adverse health effects and contribute to the heating of the atmosphere by absorbing visible solar radiation. Efforts have been made to reduce BC emissions, especially in urban areas; however, long-term measurements of BC mass concentration (MBC) are very limited in Japan. We report MBC measurements conducted in Tokyo from 2003 to 2017, showing that MBC decreased by a factor of 3 from 2003 to 2010 and was stable from 2010 to 2017. Fine particulate concentrations (PM2.5) decreased by a much smaller factor during 2003-2010. The diurnal variations of BC size distributions suggest that the BC in Tokyo originates mainly from local sources, even after 2010. Our three-dimensional model calculations show that BC from the Asian continent contributes a small portion (about 20%) of the annual average MBC in the Kanto region of Japan, which includes Tokyo. This indicates that continued reduction of BC emissions inside Japan should be effective in further decreasing MBC.


Assuntos
Carbono/química , Monitoramento Ambiental/métodos , Material Particulado/química , Poluentes Atmosféricos/química , Poluição do Ar , História do Século XXI , Humanos , Modelos Teóricos , Saúde Pública , Tóquio
20.
Chemosphere ; 252: 126573, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32220725

RESUMO

The interaction-based oxidative potential (OPint) represents the prediction of binary mixture effects distinguishing from linear additivity by including information on binary mixtures among PM components. The objective of this work is to develope a reliable estimate on the possible synergistic or antagonistic possibility of binary PM components and to quantify the combined effect. We firstly assessed the interactions among PM components in generating the OP based on DTT consumption rate and AA depletion. We started with the standard solution sequence (from 0.005 to 10 µM), including quinones (PQ, 1,2-NQ, and 1,4-NQ) and metals (Cu, Mn, and Fe). The interactions between metals were antagonistic interactions in DTT consumption. Cu showed antagonistic interaction with PQ, but additive with 1,2-NQ and 1,4-NQ. Mn interacted synergistically with 1,4-NQ in DTT consumption but antagonistically with PQ (where CPQ < 2.5 µM) and 1,4-NQ (where CPQ < 2 µM). Fe showed synergistic with quinones in investigated concentration range (from 0.01 to 5 µM). Finally, applying a moderate approach, on the basis of interaction magnitude (M = 5), resulted in 1-17% higher environmental risks, compared with the classical calculation method using simple addition. This work highlights a new approach to quantify the interaction effects between metals and quinones in PM components, and apportioning the components' contributions for PM OP.


Assuntos
Aerossóis/química , Material Particulado/química , Monitoramento Ambiental , Metais , Oxirredução , Estresse Oxidativo , Quinonas
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