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1.
Anticancer Res ; 40(5): 2591-2599, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366404

RESUMO

BACKGROUND: Physical plasma is a mixture of reactive particles and electromagnetic radiation. Due to the antimicrobial, immunomodulatory, anti-inflammatory, wound-healing promoting, and antineoplastic effects of body tempered physical plasma under atmospheric pressure (cold atmospheric plasma: CAP), CAP therapy is increasingly becoming the focus of surgical and oncological disciplines. However, when applied in practice, a potential emission of harmful noxae such as toxic nitrogen oxides must be taken into account, which was investigated in the following study. MATERIALS AND METHODS: MiniJet-R Ar CAP device was characterized with respect to NOX-specific spectra, ultraviolet radiation C (UVC) intensity in the range of 200-275 nm and the formation of NOX gases. Instrument-specific parameters such as gas flow, energy setting of the high-frequency generator, and flow rate of the carrier gas Ar were varied. To test the toxic properties of the NO2 concentrations formed by CAP, SK-OV-3 human ovarian cancer cells were incubated with different NO2 concentrations and cell growth was monitored for 120 h. RESULTS: The operation of MiniJet-R led to the formation of NO2 in the proximity of the CAP effluent. Synthesis of NO led to a NO-specific spectrum in the range of 100-275 nm, whereby UVC radiation produced reached intensities of up to 90 mW/m2 NO gas itself, however, was not detectable, as it was converted to NO2 rapidly. Cell culture incubation experiments demonstrated that NO2 in these concentration ranges had no influence on the cell growth of human cancer cells. CONCLUSION: Although no limit values were exceeded in the present study, the emission of high-energy UVC radiation and toxic NO2 is a risk factor with regard to the legal regulations on workplace protection (operator hazard) and the approval of medical devices (patient hazard). This is important for considerations regarding treatment frequency and duration. The growth inhibitory effect of CAP treatment on human cancer cells principally suggests a medical application of the MiniJet-R device, although more extensive studies will have to follow.


Assuntos
Pressão Atmosférica , Dióxido de Nitrogênio/toxicidade , Gases em Plasma/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Óxido Nítrico/análise , Dióxido de Nitrogênio/análise , Raios Ultravioleta
2.
J Environ Sci (China) ; 90: 29-40, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081325

RESUMO

To investigate the characteristics of ground level ozone (O3) for Henan Province, the ambient air quality monitoring data of 2015 and 2016 were analyzed. The result showed that the 8 h-max-O3 concentrations displayed a distinct seasonality, where the maximum and minimum values, averaging 140.41, 54.19 µg/m3, occurred in summer and winter, respectively. There is a significant correlation between meteorological factors and O3 concentration. The Voronoi neighborhood averaging analysis indicated that O3, temperature, and ultraviolet radiation in Henan province were decreased from northwest to southeast, while relative humidity and precipitation displayed the opposite trend. Besides meteorological factors, the chemical processes play an essential role in ozone formation. Reactions of NO, NO2 and O3 form a closed system, and the partitioning point of the OX-component (O3 + NO2) was at 40 and 80 µg/m3 for nitrogen oxide (NOX) in winter and summer, respectively, with NO2 dominating at higher NOx pollution and O3 being the major component at lower levels. The relationship between oxidant (OX = O3+NO2) and NOx concentrations were evaluated to understand the regional and local contribution of OX. It showed that high regional contribution occurred in the spring, whereas the highest local contribution lead to the summer peak of O3 observed in Zhengzhou. This present study reveals important environment impacts from the photochemical process and the meteorological conditions in the region with better understanding on the O3 characterization.


Assuntos
Poluentes Atmosféricos , Dióxido de Nitrogênio , Ozônio , China , Monitoramento Ambiental , Estações do Ano , Raios Ultravioleta
3.
PLoS One ; 15(2): e0228535, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32069301

RESUMO

National-scale empirical models for air pollution can include hundreds of geographic variables. The impact of model parsimony (i.e., how model performance differs for a large versus small number of covariates) has not been systematically explored. We aim to (1) build annual-average integrated empirical geographic (IEG) regression models for the contiguous U.S. for six criteria pollutants during 1979-2015; (2) explore systematically the impact on model performance of the number of variables selected for inclusion in a model; and (3) provide publicly available model predictions. We compute annual-average concentrations from regulatory monitoring data for PM10, PM2.5, NO2, SO2, CO, and ozone at all monitoring sites for 1979-2015. We also use ~350 geographic characteristics at each location including measures of traffic, land use, land cover, and satellite-based estimates of air pollution. We then develop IEG models, employing universal kriging and summary factors estimated by partial least squares (PLS) of geographic variables. For all pollutants and years, we compare three approaches for choosing variables to include in the PLS model: (1) no variables, (2) a limited number of variables selected from the full set by forward selection, and (3) all variables. We evaluate model performance using 10-fold cross-validation (CV) using conventional and spatially-clustered test data. Models using 3 to 30 variables selected from the full set generally have the best performance across all pollutants and years (median R2 conventional [clustered] CV: 0.66 [0.47]) compared to models with no (0.37 [0]) or all variables (0.64 [0.27]). Concentration estimates for all Census Blocks reveal generally decreasing concentrations over several decades with local heterogeneity. Our findings suggest that national prediction models can be built by empirically selecting only a small number of important variables to provide robust concentration estimates. Model estimates are freely available online.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/estatística & dados numéricos , Modelos Estatísticos , Poluição do Ar/história , Poluição do Ar/estatística & dados numéricos , Monóxido de Carbono/análise , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental/história , Geografia , História do Século XX , História do Século XXI , Humanos , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise , Análise de Regressão , Análise Espacial , Dióxido de Enxofre/análise , Fatores de Tempo , Estados Unidos/epidemiologia
4.
Chemosphere ; 246: 125826, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918112

RESUMO

BACKGROUND: The emerging cases of childhood scarlet fever (SF) and worsening air pollution problems in Chinese cities suggests a potential linkage between them. However, few studies had explored this association in a large childhood population. METHODS: We conducted a time-series analysis using the daily count of SF and the daily concentrations of particulate matters with an aerodynamic diameter of 2.5 (PM2.5) and 10 (PM10), as well as nitrogen dioxide (NO2) in Hangzhou, China from 2014 to 2018. Distributed lag nonlinear models were used to estimate the lag effects of PM2.5, PM10 and NO2 for a maximum lag of 10 days, which were quantified using relative risk (RR) comparing the adjusted risks at the 2.5th (extremely low effect) and 97.5th (extremely high effect) percentiles of concentration of the three air pollutants to that at the median. Stratified RRs by sex were also reported. RESULTS: Using the median concentration as reference, for extremely high effect, the RR was the highest on lag days 5, 6, and 3 for PM2.5, PM10, and NO2 respectively. While on lag day 0, the RR of PM2.5, PM10, and NO2 were 1.04 (95%CI: 0.90-1.20), 1.07 (95%CI: 0.92-1.24), and 1.08 (95%CI: 0.92-1.26) respectively, the RRs increased constantly and cumulatively to the maximum values of 1.88 (95%CI: 1.33-2.66), 1.82 (95%CI: 1.29-2.55), and 2.19 (95%CI: 1.47-3.27) for PM2.5, PM10, and NO2 respectively on lag day 10. Subgroup analyses showed that females appeared to be more vulnerable to the three pollutants than males. CONCLUSION: Our study provides evidence that PM2.5, PM10, and NO2 exert delayed effects on SF infection.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Dióxido de Nitrogênio/análise , Material Particulado/análise , Escarlatina/epidemiologia , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Criança , China/epidemiologia , Cidades , Exposição Ambiental/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco
5.
Chemosphere ; 242: 125196, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896208

RESUMO

Lanzhou, an ex-heavily polluted city, was awarded "The Award for Today's Transformative Step" in 2015 World Climate Conference at Paris for its great efforts on air quality improvement since 2012. However, the health benefits from this improvement remain unclear. Therefore, we collected time-series data covering deaths, weather variables and air pollutants during the two periods (2004-2009, 2014-2017) and fitted single-pollutant models using the generalized additive models to evaluate the change of mortality risks associated with air pollutants in Lanzhou. Results showed that the annual average concentrations of respirable particulate matter (PM10) and sulfur dioxide (SO2) dropped by 19.28% and 66.29%, while the nitrogen dioxide (NO2) increased by 16.61% in 2014-2017 compared to 2004-2009. During the period 2004-2009, we found a 10-µg/m3 increase in PM10 (lag 2), SO2 (lag 0-5) and NO2 (lag 0-5) were associated with mortality increments of 0.12% (95% CI: 0.01, 0.22), 0.86% (95% CI: 0.42, 1.31) and 1.29% (95% CI: 0.70, 1.90), respectively. During the period 2014-2017, the association between PM10 and daily deaths was not significant, but we observed a 10-µg/m3 increase in SO2 (lag 0-5) and NO2 (lag 4) were related to mortality increments of 4.23% (95% CI: 1.82, 6.70) and 0.85% (95% CI: 0.19, 1.52), respectively. From 2004-2009 to 2014-2017, we observed markedly decline of mortality risk due to PM10, but not SO2 or NO2. In conclusion, the mortality risk of PM10 in Lanzhou has declined obviously after the substantially improved air quality due to the enforcement of air pollution controlling policies.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Mortalidade/tendências , Poluição do Ar/análise , China/epidemiologia , Clima , Poluentes Ambientais , Humanos , Dióxido de Nitrogênio/análise , Material Particulado/análise , Dióxido de Enxofre/análise , Tempo (Meteorologia)
6.
Sci Total Environ ; 705: 135810, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31972944

RESUMO

BACKGROUND: To date, the effect of household airborne pollutants on the association between airborne endotoxin and lung function of schoolchildren is unknown. OBJECTIVES: The objective of this study is to evaluate whether indoor air pollutants such as carbon monoxide (CO), carbon dioxide (CO2), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), particulate matter with aerodynamic diameter <10 and 2.5 µm (PM10, PM2.5) can modify the association between airborne endotoxin and school children's lung function in a heavy industrial city in Taiwan. METHODS: We recruited 120 elementary school-age children in Kaohsiung City, Taiwan. Aerosol samples were collected on a filter membrane for 24 h period and then analyzed for endotoxin. Air pollutants were measured for 24 h in living rooms while school children's lung function was measured. The modification of air pollutants on the relationship between airborne endotoxin and children's lung function was estimated after adjusting the gender, age, height, weight, and case-control status. RESULTS: We found that both O3 and PM10 concentrations significantly modified the relationships between airborne endotoxin and school children's lung function. Among children living in homes with O3 ≥ 0.01 ppm or PM10 ≥ 62 µg/m3, airborne endotoxin was negatively associated with lung functions, whereas among those living in homes with O3 < 0.01 ppm or PM10 < 62 µg/m3, airborne endotoxin was positively associated with lung functions. CONCLUSIONS: The indoor air pollutant concentration of O3 and PM10 modifies the association between airborne endotoxin and school children's lung function.


Assuntos
Poluição do Ar , Pulmão , Poluentes Atmosféricos , Criança , Cidades , Endotoxinas , Humanos , Dióxido de Nitrogênio , Ozônio , Material Particulado , Testes de Função Respiratória , Dióxido de Enxofre , Taiwan
7.
Environ Pollut ; 259: 113875, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31918142

RESUMO

Kriging interpolation and land use regression (LUR) have characterized the spatial variability of long-term nitrogen dioxide (NO2), but there has been little research on combining these two methods to capture small-scale spatial variation. Furthermore, studies predicting NO2 exposure are almost exclusively based on traffic-related variables, which may not be transferable to Taiwan, a typical Asian country with diverse local emission sources, where densely distributed temples and restaurants may be important for NO2 levels. To advance the exposure estimates in Taiwan, a hybrid kriging/LUR model incorporates culture-specific sources as potential predictors. Based on 14-year NO2 observations from 73 monitoring stations across Taiwan, a set of interpolated NO2 values were generated through a leave-one-out ordinary kriging algorithm, and this was included as an explanatory variable in the stepwise LUR procedures. Kriging interpolated NO2 and culture-specific predictors were entered in the final models, which captured 90% and 87% of NO2 variation in annual and monthly resolution, respectively. Results from 10-fold cross-validation and external data verification demonstrate robust performance of the developed models. This study demonstrates the value of incorporating the kriging-interpolated estimates and culture-specific emission sources into the traditional LUR model structure for predicting NO2, which can be particularly useful for Asian countries.


Assuntos
Poluentes Atmosféricos , Modelos Teóricos , Dióxido de Nitrogênio , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Dióxido de Nitrogênio/análise , Análise de Regressão , Análise Espaço-Temporal , Taiwan
8.
Environ Sci Pollut Res Int ; 27(8): 8673-8683, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31907807

RESUMO

In dryland cropping ecosystems, nitrogen (N) fertilization causes changes in soil biochemical cycling and influences the crop biomass and grain yield. Based on a long-term field experiment involving three N rates (0 (N0), 160 (N160), and 320 (N320) kg N ha-1 year-1), we measured nitrous oxide (N2O) and carbon dioxide (CO2) emissions from wheat fields and determined the soil organic carbon (SOC), total N, microbial biomass C (MBC), and N (MBN), mineralized C (Cmin) and N (Nmin) concentrations and the bacterial community composition. The results showed that N fertilization significantly (P < 0.05) increased N2O and CO2 emissions. N fertilization also significantly (P < 0.05) increased SOC by 13.2%, total N by 7.4%, MBN by 34.3%, Cmin by 15.5%, and Nmin by 27.8%, as well as the soil bacterial diversity and abundances of N cycling functional groups (by 149%). Additionally, N2O and CO2 emissions were positively and linearly correlated with NH4-N and NO3-N concentrations and positively correlated with SOC, total N, MBN, and the number of bacterial species, as well as most of the bacterial phyla and functional groups. These results suggest that N fertilizer applied to the dryland soils improved soil fertility and changed the soil bacterial community composition and function, thus increased N2O and CO2 emissions. Therefore, to mitigate greenhouse gas emissions and maintain soil fertility for wheat production, an optimized N fertilizer rate should be applied in the southern region of the Loess Plateau in China.


Assuntos
Agricultura , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Dióxido de Nitrogênio/análise , Microbiologia do Solo , Triticum , Bactérias , Carbono , China , Ecossistema , Monitoramento Ambiental , Fertilizantes , Microbiota , Nitrogênio , Óxido Nitroso , Solo
9.
Environ Pollut ; 256: 113434, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672350

RESUMO

BACKGROUND: Little information exists on interaction effects between air pollution and influenza vaccination on allergic respiratory diseases. We conducted a large population-based study to evaluate the interaction effects between influenza vaccination and long-term exposure to ambient air pollution on allergic respiratory diseases in children and adolescents. METHODS: A cross-sectional study was investigated during 2012-2013 in 94 schools from Seven Northeastern Cities (SNEC) in China. Questionnaires surveys were obtained from 56 137 children and adolescents aged 2-17 years. Influenza vaccination was defined as receipt of the influenza vaccine. We estimated air pollutants exposure [nitrogen dioxide (NO2) and particulate matter with aerodynamic diameters ≤1 µm (PM1), ≤2.5 µm (PM2.5) and ≤10 µm (PM10)] using machine learning methods. We employed two-level generalized linear mix effects model to examine interactive effects between influenza vaccination and air pollution exposure on allergic respiratory diseases (asthma, asthma-related symptoms and allergic rhinitis), after controlling for important covariates. RESULTS: We found statistically significant interactions between influenza vaccination and air pollutants on allergic respiratory diseases and related symptoms (doctor-diagnosed asthma, current wheeze, wheeze, persistent phlegm and allergic rhinitis). The adjusted ORs for doctor-diagnosed asthma, current wheeze and allergic rhinitis among the unvaccinated group per interquartile range (IQR) increase in PM1 and PM2.5 were significantly higher than the corresponding ORs among the vaccinated group [For PM1, doctor-diagnosed asthma: OR: 1.89 (95%CI: 1.57-2.27) vs 1.65 (95%CI: 1.36-2.00); current wheeze: OR: 1.50 (95%CI: 1.22-1.85) vs 1.10 (95%CI: 0.89-1.37); allergic rhinitis: OR: 1.38 (95%CI: 1.15-1.66) vs 1.21 (95%CI: 1.00-1.46). For PM2.5, doctor-diagnosed asthma: OR: 1.81 (95%CI: 1.52-2.14) vs 1.57 (95%CI: 1.32-1.88); current wheeze: OR: 1.46 (95%CI: 1.21-1.76) vs 1.11 (95%CI: 0.91-1.35); allergic rhinitis: OR: 1.35 (95%CI: 1.14-1.60) vs 1.19 (95%CI: 1.00-1.42)]. The similar patterns were observed for wheeze and persistent phlegm. The corresponding p values for interactions were less than 0.05, respectively. We assessed the risks of PM1-related and PM2.5-related current wheeze were decreased by 26.67% (95%CI: 1.04%-45.66%) and 23.97% (95%CI: 0.21%-42.08%) respectively, which was attributable to influenza vaccination (both p for efficiency <0.05). CONCLUSIONS: Influenza vaccination may play an important role in mitigating the detrimental effects of long-term exposure to ambient air pollution on childhood allergic respiratory diseases. Policy targeted at increasing influenza vaccination may yield co-benefits in terms of reduced allergic respiratory diseases.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Doenças Respiratórias/epidemiologia , Adolescente , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Asma/epidemiologia , Criança , Pré-Escolar , China , Cidades , Estudos Transversais , Feminino , Humanos , Hipersensibilidade/epidemiologia , Influenza Humana , Modelos Logísticos , Masculino , Dióxido de Nitrogênio , Material Particulado/análise , Transtornos Respiratórios , Sons Respiratórios , Fatores de Risco , Instituições Acadêmicas , Inquéritos e Questionários , Vacinação
10.
Environ Pollut ; 256: 113422, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672364

RESUMO

Evidence suggests that residential greenness may be protective of high blood pressure, but there is scarcity of evidence on the associations between greenness around schools and blood pressure among children. We aimed to investigate this association in China. Our study included 9354 children from 62 schools in the Seven Northeastern Cities Study. Greenness around each child's school was measured by NDVI (Normalized Difference Vegetation Index) and SAVI (Soil-Adjusted Vegetation Index). Particulate matter ≤ 1 µm (PM1) concentrations were estimated by spatiotemporal models and nitrogen dioxide (NO2) concentrations were collected from air monitoring stations. Associations between greenness and blood pressure were determined by generalized linear and logistic mixed-effect models. Mediation by air pollution was assessed using mediation analysis. Higher greenness was consistently associated with lower blood pressure. An increase of 0.1 in NDVI corresponded to a reduction in SBP of 1.39 mmHg (95% CI: 1.86, -0.93) and lower odds of hypertension (OR = 0.76, 95% CI: 0.69, 0.82). Stronger associations were observed in children with higher BMI. Ambient PM1 and NO2 mediated 33.0% and 10.9% of the association between greenness and SBP, respectively. In summary, greater greenness near schools had a beneficial effect on blood pressure, particularly in overweight or obese children in China. The associations might be partially mediated by air pollution. These results might have implications for policy makers to incorporate more green space for both aesthetic and health benefits.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Hipertensão/epidemiologia , Desenvolvimento Sustentável , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Pressão Sanguínea , Criança , China/epidemiologia , Cidades , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/análise , Obesidade , Material Particulado/análise , Risco , Instituições Acadêmicas
11.
Sci Total Environ ; 704: 135772, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31838301

RESUMO

Epidemiology studies over the past five decades have provided convincing evidence that exposure to air pollution is associated with multiple adverse health outcomes, including increased mortality. Air pollution is a complex mixture of particles, vapors and gases emitted from natural and anthropogenic sources as well as formed through photochemical transformation processes. In metropolitan areas, air pollutants from combustion emissions feature a blend of emitted particles, oxides of carbon, sulfur and nitrogen, volatile organic compounds, and secondary reaction products, such as ozone, nitrogen dioxide, and secondary organic aerosols. Because many of the primary and transformed pollutants track together, their relative contributions to health outcomes are difficult to disentangle. Aside from the criteria pollutants ozone and nitrogen dioxide and some of the simpler aldehydes (e.g. formaldehyde and acrolein), other products from photochemical processes are a particularly vexing class of chemicals to investigate since they comprise a dynamic ill-defined complex mixture in both particulate and gas phases. The purpose of this review was to describe and compare health effects of freshly emitted versus oxidatively or photochemically aged air pollutants. In some cases, (e.g. single volatile organic compounds) photochemical transformation resulted in marked enhancements in toxicity through formation of both known and unidentified reaction products, while in other examples (e.g. aging of automobile emissions) the potentiation of effect was variable. The variation in experimental design, aging system employed, concentration and type of starting agent, and toxicity endpoints make comparisons between different studies exceedingly difficult. A more systematic approach with a greater emphasis on higher throughput screening and computational toxicology is needed to fully answer under what conditions oxidatively- or photochemically-transformed pollutants elicit greater health effects than primary emissions.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Aldeídos/análise , Humanos , Dióxido de Nitrogênio/análise , Ozônio , Material Particulado/análise , Compostos Orgânicos Voláteis/análise
12.
Sci Total Environ ; 699: 134397, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31677469

RESUMO

Children are vulnerable to air pollution-induced lung function deficits, and the prevalence of obesity has been increasing in children. To evaluate the joint effects of long-term PM1 (particulate matter with an aerodynamic diameter ≤ 1.0 µm) exposure and obesity on children's lung function, a cross-sectional sample of 6740 children (aged 7-14 years) was enrolled across seven northeastern Chinese cities from 2012 to 2013. Weight and lung function, including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), peak expiratory flow (PEF), and maximal mid-expiratory flow (MMEF), were measured according to standardized protocols. Average PM1, PM2.5, PM10 and nitrogen dioxide (NO2) exposure levels were estimated using a spatiotemporal model, and sulphur dioxide (SO2) and ozone (O3) exposure were estimated using data from municipal air monitoring stations. Two-level logistic regression and general linear models were used to analyze the joint effects of body mass index (BMI) and air pollutants. The results showed that long-term air pollution exposure was associated with lung function impairment and there were significant interactions with BMI. Associations were stronger among obese and overweight than normal weight participants (the adjusted odds ratios (95% confidence intervals) for PM1 and lung function impairments in three increasing BMI categories were 1.50 (1.07-2.11) to 2.55 (1.59-4.07) for FVC < 85% predicted, 1.44 (1.03-2.01) to 2.51 (1.53-4.11) for FEV1 < 85% predicted, 1.34 (0.97-1.84) to 2.04 (1.24-3.35) for PEF < 75% predicted, and 1.34 (1.01-1.78) to 1.93 (1.26-2.95) for MMEF < 75% predicted). Consistent results were detected in linear regression models for PM1, PM2.5 and SO2 on FVC and FEV1 impairments (PInteraction < 0.05). These modification effects were stronger among females and older participants. These results can provide policy makers with more comprehensive information for to develop strategies for preventing air pollution induced children's lung function deficits among children.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Obesidade/epidemiologia , Adolescente , Poluentes Atmosféricos/análise , Criança , China/epidemiologia , Cidades , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/efeitos dos fármacos , Masculino , Dióxido de Nitrogênio/análise , Sobrepeso , Ozônio/análise , Material Particulado/análise , Testes de Função Respiratória , Dióxido de Enxofre , Capacidade Vital
13.
Chemosphere ; 239: 124667, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31499299

RESUMO

Exposure to air pollution can have both short-term and long-term effects on health. However, the relationships between specific pollutants and their effects can be obscured by characteristics of both the pollution and the exposed population. One way of elucidating the relationships is to link exposures and internal changes at the level of the individual. To this end, we combined personal exposure monitoring (59 individuals, Oxford Street II crossover study) with mass-spectrometry-based analyses of putative serum albumin adducts (fixed-step selected reaction monitoring). We attempted to infer adducts' identities using data from another, higher-resolution mass spectrometry method, and were able to detect a semi-synthetic standard with both methods. A generalised least squares regression method was used to test for associations between amounts of adducts and pollution measures (ambient concentrations of nitrogen dioxide and particulate matter), and between amounts of adducts and short-term health outcomes (measures of lung health and arterial stiffness). Amounts of some putative adducts (e.g., one with a positive mass shift of ∼143 Da) were associated with exposure to pollution (11 associations), and amounts of other adducts were associated with health outcomes (eight associations). Adducts did not appear to provide a link between exposures and short-term health outcomes.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Albumina Sérica/química , Estudos Cross-Over , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/análise , Material Particulado/análise , Análise de Regressão
14.
Sci Total Environ ; 700: 134527, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629262

RESUMO

This study presents an overview of the air pollution levels in the Maltese Islands including trends in particulate matter (PM), ozone (O3) and nitrogen dioxide (NO2) at four monitoring stations in Malta and one in Gozo between 2008 and 2017. In addition, the health impacts associated with long-term exposure to annual mean PM2.5 and NO2 are estimated at each site. Irrespective of the site, PM10 and PM2.5 concentrations show statistically significant decreasing trends while statistically significant increasing trends are noted for the coarse fraction, PM2.5-10 and O3. Trends for the different pollutants vary for each site and differ from the overall trend both in magnitude and sign especially for NO2 concentrations. The attributable fraction (AF) associated with long-term exposure to PM2.5 and NO2 ranges from 0.67% (CI: 0.27%,1.07%) in Gharb to 11.79% (CI: 7.77,15.45) in Msida (2011). The corresponding attributable mortality is estimated to reach a maximum of 119 (CI: 78,156) attributable deaths associated with long-term exposure to PM2.5 in Msida in 2011. This paper thus highlights the importance of continuous air quality monitoring in distinctively different conurbations especially for pollutants showing increasing trends and is the first to outline the potential long-term health effects of air pollutant concentrations in the Maltese Islands.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Humanos , Ilhas , Estudos Longitudinais , Malta , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise
15.
Sci Total Environ ; 701: 134943, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31731203

RESUMO

Biochar amendment has been recommended as a potential strategy to mitigate nitrous oxide (N2O) and nitric oxide (NO) emissions for wheat production, but its mechanism and effective duration are not well understood. The 1-octyne and 2-pheny l-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO) in combination with potassium chlorate were used to evaluate the relative contribution of ammonia-oxidizing bacteria (AOB) and archaea (AOA) to potential ammonia oxidation (PAO) and N2O and NO production as affected by biochar. Acidic and alkaline soils were collected during wheat-growing season, and four treatments were installed in each soil type: CK, urea alone; BE, biochar-enriched soil for 2-6 years; FB, fresh biochar added to CK; and AB, aged biochar added to CK. The results showed that octyne and PTIO efficiently assessed AOB and AOA activities in soil incubation. The AOB-driven PAO in acidic soil was largely enhanced by increased soil pH in BE and FB treatments, whereas AOA-driven PAO was not. And the contribution of AOB to PAO exceeded 80% in alkaline soil. The N2O and NO production were positively correlated with PAO in both soils. BE treatment decreased the direct N2O and NO production in alkaline soil, while both BE and FB treatments decreased the N2O and NO yields in acidic soil, indicating that biochar mitigated soil N2O and NO emissions for wheat production. The lack of differences between AB and CK treatments indicated that aged biochar lost its initial effects on PAO, while the biochar-enriched soil amended with biochar years earlier still functioned similarly as fresh biochar.


Assuntos
Agricultura/métodos , Poluição do Ar/prevenção & controle , Carvão Vegetal/química , Óxido Nítrico/análise , Dióxido de Nitrogênio/análise , Triticum/crescimento & desenvolvimento , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Amônia , Archaea , Betaproteobacteria , Fertilizantes , Óxido Nitroso , Oxirredução , Estações do Ano , Microbiologia do Solo , Ureia
16.
Environ Sci Pollut Res Int ; 27(7): 7289-7298, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31884542

RESUMO

Antibiotics are commonly used in intensive farming, leading to multiple antibiotic residue in livestock waste. However, the effects of multiple antibiotics on the emissions of greenhouse gas and ammonia remain indistinct. This paper selects sulfamethoxazole and norfloxacin to represent two different types of antibiotics to explore their effects on gaseous emissions. Four treatments including CK (control), SMZ (spiked with 5 mg kg-1 DW sulfamethoxazole), NOR (spiked with 5 mg kg-1 DW norfloxacin), and SN (spiked with 5 mg kg-1 DW sulfamethoxazole and 5 mg kg-1 DW norfloxacin) were composted for 65 days. Coexistence of sulfamethoxazole and norfloxacin facilitated the biodegradation of organic carbon, and significantly (p < 0.05) increased the cumulative CO2 emission by 31.9%. The cumulative CH4 emissions were decreased by 6.19%, 23.7%, and 27.6% for SMZ, NOR, and SN, respectively. The total NH3 volatilization in SMZ and NOR rose to 1020 and 1190 mg kg-1 DW, respectively. The individual existence of sulfamethoxazole significantly (p < 0.05) ascended the N2O emission rate in the first 7 days due to the increase of NO2--N content. In addition, coexistence of sulfamethoxazole and norfloxacin notably dropped the total greenhouse gas emission (subtracting CO2) by 15.5%.


Assuntos
Monóxido de Carbono/química , Compostagem , Gases de Efeito Estufa , Dióxido de Nitrogênio/química , Amônia , Animais , Antibacterianos/química , Esterco , Solo , Suínos
17.
Sci Total Environ ; 698: 134212, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783470

RESUMO

Rice, one of the major sources of CH4 and N2O emissions, is also the largest consumer of water resources. Mild alternate wetting and drying (AWD) irrigation is widely adopted to save irrigation water resources and maintain rice production, but its effects on CH4 and N2O emissions are unclear. In addition, previous studies have revealed different effects of mid-season drainage on global warming potential (GWP), owing to the different criteria used. In this study, a pot experiment was conducted to investigate the effects of mild AWD irrigation and mid-season drainage (a specific soil moisture) on CH4 and N2O emissions during rice cultivation. Four water management systems were applied: AWD + D0 (mild AWD irrigation without mid-season drainage), AWD + D1 (mild AWD irrigation with mid-season drainage), CF + D0 (continuous flooding without mid-season drainage) and CF + D1 (continuous flooding with mid-season drainage); nitrogen was applied at two levels (N90 and N180) along with each treatment. The results showed that mild AWD irrigation reduced CH4 cumulative emissions by an average of 87.1% but increased N2O cumulative emissions by an average of 280% compared to the values observed with CF irrigation. Mid-season drainage did not affect N2O emissions but interrupted CH4 fluxes and significantly reduced CH4 cumulative emissions. CH4 and N2O cumulative emissions were reduced by an average of 25.0% and 54.2%, respectively, with N90 application compared to values observed with N180 application. Unexpectedly, mild AWD irrigation did not reduce GWP and yield-scaled GWP unlike CF irrigation because a high N2O emission peak occurred during mild AWD irrigation. Furthermore, we observed an obvious trade-off between CH4 and N2O. We suggest that maintaining flooding during nitrogen application but applying mild AWD irrigation for the remaining period may be helpful in reducing CH4 and N2O emissions and GWP.


Assuntos
Agricultura/métodos , Poluentes Atmosféricos/análise , Metano/análise , Dióxido de Nitrogênio/análise , Oryza
18.
Environ Sci Technol ; 54(3): 1372-1384, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31851499

RESUMO

NO2 is a combustion byproduct that has been associated with multiple adverse health outcomes. To assess NO2 levels with high accuracy, we propose the use of an ensemble model to integrate multiple machine learning algorithms, including neural network, random forest, and gradient boosting, with a variety of predictor variables, including chemical transport models. This NO2 model covers the entire contiguous U.S. with daily predictions on 1-km-level grid cells from 2000 to 2016. The ensemble produced a cross-validated R2 of 0.788 overall, a spatial R2 of 0.844, and a temporal R2 of 0.729. The relationship between daily monitored and predicted NO2 is almost linear. We also estimated the associated monthly uncertainty level for the predictions and address-specific NO2 levels. This NO2 estimation has a very high spatiotemporal resolution and allows the examination of the health effects of NO2 in unmonitored areas. We found the highest NO2 levels along highways and in cities. We also observed that nationwide NO2 levels declined in early years and stagnated after 2007, in contrast to the trend at monitoring sites in urban areas, where the decline continued. Our research indicates that the integration of different predictor variables and fitting algorithms can achieve an improved air pollution modeling framework.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Algoritmos , Monitoramento Ambiental , Dióxido de Nitrogênio , Incerteza , Estados Unidos
19.
Chemosphere ; 240: 124954, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31726583

RESUMO

The authors have observed that the function linking health outcomes with exposure to particulate-matter (PM) follows a biphasic pattern. It peaks around levels of PM10≤100 µg/m3, then weakens and rises again at PM10 levels in the range of hundreds. This could be due to a different nature of PM, the first peak reflecting a stronger anthropogenic and the second - weaker non-anthropogenic particles' effect. The current analysis is focused at the biphasic pattern on the association between PM levels with BG and asthma exacerbations. Pollutants were assessed by local monitoring stations and a satellitebased model. Local weekends/holidays were used to define nonanthropogenic levels of pollutants featured by lower Nitrogen Dioxide, the proxy for anthropogeneity. The association of PM10 with health outcomes within 24-48h lag was explored using spline functions of generalized additive models. Analysis of 546,420 BG tests (43,569 subjects) showed an almost linear association of PM10 with asthma with BG during the days with anthropogenic activity and no trend on other days. Analysis of asthmatic exacerbations within 1576 children showed no heterogeneity in association with PM10 by anthropogeneity levels, possibly indicating a mechanical impact on alveolar as the main trigger for exacerbations rather than PM10 chemical composition.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Atividades Humanas , Material Particulado/análise , Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Antropologia/métodos , Asma/induzido quimicamente , Asma/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Tamanho da Partícula
20.
Int J Hyg Environ Health ; 223(1): 116-123, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31588015

RESUMO

Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) are commonly used biomarkers of oxidative stress. However, their associations with air pollutant exposure have not been consistent across studies. We hypothesize that the inconsistency is partly due to confounding of circulating melatonin. We analyzed urinary 6-sulfatoxymelatonin (aMT6s), a surrogate of circulating melatonin, along with 8-OHdG and MDA, in 159 healthy adults who had not taken melatonin supplementation. Within the natural range of endogenously-generated aMT6s (0.3-93.5 ng/mg creatinine) measured in this study, increasing aMT6s levels were significantly associated with increasing concentrations of 8-OHdG and MDA. Measurements of PM2.5, ozone (O3), and nitrogen dioxide (NO2), coupled with time-activity data, were used to calculate time-averaged personal exposures 12 -hour (12h) and 24-hour (24h) prior to urine collection. Without controlling for aMT6s, the relationships between pollutant exposure and 8-OHdG or MDA were not clear. After controlling for aMT6s, an interquartile range (IQR) increase in 12h PM2.5 and 12h NO2 exposure was associated with 6.1% [95%CI: 1.6%-10.8%] and 8.6% [1.3%-16.5%] increase in MDA, respectively. An IQR increase in 12h O3 exposure was associated with a 5.7% [1.9%-9.7%] in 8-OHdG. The findings suggest the need for controlling for aMT6s as a confounder in using urinary 8-OHdG and MDA as biomarkers of oxidative stress related to short-term air pollution exposure.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Melatonina/metabolismo , Estresse Oxidativo/fisiologia , Adulto , Biomarcadores , Desoxiguanosina , Monitoramento Ambiental , Feminino , Humanos , Masculino , Malondialdeído , Dióxido de Nitrogênio , Ozônio , Material Particulado/análise
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