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Shipping pollution emission associated with increased cardiovascular mortality: A time series study in Guangzhou, China
2018
Lin, Hualiang | Tao, Jun | Qian, Zhengmin (Min) | Ruan, Zengliang | Xu, Yanjun | Hang, Jian | Xu, Xiaojun | Liu, Tao | Guo, Yuming | Zeng, Weilin | Xiao, Jianpeng | Guo, Lingchuan | Li, Xing | Ma, Wenjun
Substantial evidence has linked short-term exposure to ambient fine particulate matter (PM2.5) with increased cardiovascular mortality, however, the specific chemical constituent and emission source responsible for this effect remained largely unclear. A time series Poisson model was employed to quantify the association of cardiovascular mortality with two sets of shipping pollution emission: nickel (Ni), vanadium (V) (the indices of shipping emission) and estimated shipping emission using a source apportionment approach in Guangzhou, China in 2014. We observed that Ni, V, and estimated shipping emission in PM2.5 were associated with increased cardiovascular mortality, an inter-quartile range (IQR) increase in lag2 Ni was associated with 4.60% (95% CI: 0.14%, 9.26%) increase in overall cardiovascular mortality, and 13.35% (95% CI: 5.54%, 21.75%) increase in cerebrovascular mortality; each IQR increase of lag1 V was correlated with 6.01% (95% CI: 1.83%, 10.37%) increase in overall cardiovascular mortality, and 11.02% (95% CI: 3.15%, 19.49%) increase in cerebrovascular mortality; and each IQR increase in lag1 shipping emission was associated with 5.55% (95% CI: 0.78%, 10.54%) increase in overall cardiovascular mortality, and 10.39% (95% CI: 1.43%, 20.14%) increase in cerebrovascular mortality. The results remained robust to adjustment for PM2.5 mass and gaseous air pollutants. This study suggests that shipping emission is an important detrimental factor of cardiovascular mortality, and should be emphasized in air pollution control and management in order to protect the public health in Guangzhou, China.
اظهر المزيد [+] اقل [-]A systematic risk characterization related to the dietary exposure of the population to potentially toxic elements through the ingestion of fruit and vegetables from a potentially contaminated area. A case study: The issue of the "Land of Fires" area in Campania region, Italy
2018
Esposito, Francesco | Nardone, Antonio | Fasano, Evelina | Scognamiglio, Gelsomina | Esposito, Daniela | Agrelli, Diana | Ottaiano, Lucia | Fagnano, Massimo | Adamo, Paola | Beccaloni, Eleonora | Vanni, Fabiana | Cirillo Sirri, Teresa
Potentially toxic elements are widespread soil contaminants, whose occurrence could entail a concern for human health upon ingestion of fruit and vegetables harvested in a polluted area. This work set out to evaluate the concentrations of lead and cadmium as well as the levels of thirteen heavy metals for which a limit value is yet to be established by the food safety authorities, in order to perform a risk characterization related to the dietary intake of these metals and to provide a scientific opinion with wider relevance in the light of current worldwide regulatory issues. The sampling consisted of fruit and vegetables grown in a potentially contaminated area of southern Italy due to the illegal dump of hazardous wastes. An evaluation of the dietary exposure through the calculation of the Hazard Index (HI), the Maximum Cumulative Ratio (MCR) and the Target Cancer Risk (TCR) was adopted to this end. The results revealed that about the 30% of samples showed quantifiable levels of chemicals and no significant difference emerged between the potentially polluted area and the nearby cities that were selected as a control landfill site. The overall risk characterization for non-carcinogenic endpoints showed that the HI did not reach unsafe values, except for a small number of samples mainly because of aberrant occurrences and, in any case, the cumulative toxicity was mainly driven by thallium and vanadium. As far as the carcinogenic effects of arsenic are concerned, the distribution of TCR values broadly lay below the safety threshold; a certain percentage of data, however, exceeded this limit and should be taken into account for the enforcement of future regulatory thresholds.
اظهر المزيد [+] اقل [-]Socio-demographic, lifestyle, and dietary determinants of essential and possibly-essential trace element levels in adipose tissue from an adult cohort
2018
Rodríguez-Pérez, Celia | Vrhovnik, Petra | González-Alzaga, Beatriz | Fernández, Mariana F. | Martin-Olmedo, Piedad | Olea, Nicolás | Fiket, Željka | Kniewald, Goran | Arrebola, Juan P.
There is increasing evidence linking levels of trace elements (TEs) in adipose tissue with certain chronic conditions (e.g., diabetes or obesity). The objectives of this study were to assess concentrations of a selection of nine essential and possibly-essential TEs in adipose tissue samples from an adult cohort and to explore their socio-demographic, dietary, and lifestyle determinants. Adipose tissue samples were intraoperatively collected from 226 volunteers recruited in two public hospitals from Granada province. Trace elements (Co, Cr, Cu, Fe, Mn, Mo, Se, V, and Zn) were analyzed in adipose tissue by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Data were collected on socio-demographic characteristics, lifestyle, diet, and health status by face-to-face interview. Predictors of TE concentrations were assessed by using multivariable linear and logistic regression. All TEs were detected in all samples with the exception of Se (53.50%). Iron, zinc, and copper showed the highest concentrations (42.60 mg/kg, 9.80 mg/kg, and 0.68 mg/kg, respectively). Diet was the main predictor of Cr, Fe, Mo, and Se concentrations. Body mass index was negatively associated with all TEs (β coefficients = −0.018 to −0.593, p = 0.001–0.090) except for Mn and V. Age showed a borderline-significant positive correlation with Cu (β = 0.004, p = 0.089). Residence in a rural or semi-rural area was associated with increased Co, Cr, Fe, Mo, Mn, V and Zn concentrations and with β coefficients ranging from 0.196 to 0.544 (p < 0.05). Furthermore, individuals with higher educational level showed increased Cr, Co, Fe and V concentrations (β coefficients = 0.276–0.368, p = 0.022–0.071). This is the first report on the distribution of these TEs in adipose tissue and on their determinants in a human cohort and might serve as an initial step in the elucidation of their clinical relevance.
اظهر المزيد [+] اقل [-]Environmental exposure to metals and the risk of hypertension: A cross-sectional study in China
2018
Wu, Weixiang | Jiang, Shunli | Zhao, Qiang | Zhang, Ke | Wei, Xiaoyun | Zhou, Tong | Liu, Dayang | Zhou, Hao | Zeng, Qiang | Cheng, Liming | Miao, Xiaoping | Lü, Qing
Metal pollution is a severe environmental issue in China, which has been recently linked with the risk of hypertension. However, relevant epidemiological studies are limited. The present exploratory study was conducted to assess the associations of environmental exposure to metals with the odds of hypertension as well as blood pressure (BP) levels using urine samples in a Chinese general population. From May 2016 to April 2017, a total of 823 eligible participants were consecutively enrolled in our study in Wuhan, China. Hypertension was defined as systolic BP (SBP) of ≥140 mmHg or diastolic BP (DBP) of ≥90 mmHg, a self-reported physician diagnosis, or current use of antihypertensive medication. We used urine samples as biomarkers to reflect the levels of environmental exposure to 20 metals. Multivariable regression models were applied to assess the potential association. Multi-metal models were conducted to investigate the impacts of co-exposure to various metals. Based on the results from various models, positive trends for increased odds of hypertension with increasing quartiles of vanadium (V), iron (Fe), zinc (Zn) and selenium (Se) were suggested. Compared with those in the lowest quartiles, participants in the highest quartiles of V, Fe, Zn and Se had a 4.4-fold, 4.9-fold, 4.2-fold and 2.5-fold increased odds of having hypertension, respectively. High urinary Hg level was found to increase the levels of DBP. Individuals in the highest group of Hg were found to have a 4.3 mmHg higher level of DBP. Our findings suggest that environmental exposure to V, Fe, Zn, Se and Hg might increase the risk of hypertension or elevate the levels of BP. These findings warrant further prospective studies in a larger population.
اظهر المزيد [+] اقل [-]Co-combustion of anthracite coal and wood pellets: Thermodynamic analysis, combustion efficiency, pollutant emissions and ash slagging
2018
Guo, Feihong | Zhong, Zhaoping
This work presents studies on the co-combustion of anthracite coal and wood pellets in fluidized bed. Prior to the fluidized bed combustion, thermogravimetric analysis are performed to investigate the thermodynamic behavior of coal and wood pellets. The results show that the thermal decomposition of blends is divided into four stages. The co-firing of coal and wood pellets can promote the combustion reaction and reduce the emission of gaseous pollutants, such as SO₂ and NO. It is important to choose the proportion of wood pellets during co-combustion due to the low combustion efficiency caused by large pellets with poor fluidization. Wood pellets can inhibit the volatilization of trace elements, especially for Cr, Ni and V. In addition, the slagging ratio of wood pellets ash is reduced by co-firing with coal. The research on combustion of coal and wood pellets is of great significance in engineering.
اظهر المزيد [+] اقل [-]Major and minor elemental compositions of streambed biofilms and its implications of riverine biogeochemical cycles
2018
Mori, Naoki | Sugitani, Kenichiro | Yamamoto, Mariko | Tomioka, Rie | Sato, Miyako | Harada, Naomi
Chemical compositions of streambed biofilms from a major river of central Japan (the Kushida River) were obtained, with data of associated sediments (fine-grained fractions < 63 μm) and dissolved components of waters, in order to provide preliminary information about biogeochemical significance of streambed biofilms. During the sampling period (July 31st to August 3rd, 2013), dissolved components of the river waters were influenced by the dam reservoir. Concentrations of NO₃⁻, silica (as Si), SO₄²⁻, PO₄³⁻ and Ca²⁺ decreased across the dam, whereas Fe and Mn increased across the dam, and then decreased downstream rapidly. Streambed biofilms contain significant amount of non-nutrient elements such as Al (up to 21% as Al₂O₃ on water and others-free basis), indicating that they are contaminated as siliciclatic (silt and clay) materials. Siliciclastic materials in the biofilms are basically compositionally similar to fine-grained (<63 μm) fractions of streambed sediments. However, some elements such as Ca, P, Mn, and Zn are markedly enriched in the biofilms. Particularly, Mn concentrations in the biofilm samples collected just below the dam reservoir are very high (∼4.0 wt %), probably due to accumulation from the discharged water. Concentrations of trace elements such as P, Cr, Cu, Zn and V appear to be controlled by amounts of Fe-oxides and/or Mn-oxides in biofilms. Numbers of factors are involved in controlling chemical compositions of streambed biofilms, including amount of contaminated siliciclastics, authigenic mineral formation, adsorption of dissolved materials and microbial metabolisms. As demonstrated by this study, systematic analyses including major elements and comparison with associated sediments and waters could reveal biogeochemistry of this complex system.
اظهر المزيد [+] اقل [-]Road proximity influences indoor exposures to ambient fine particle mass and components
2018
Huang, Shaodan | Lawrence, Joy | Kang, Choong-Min | Li, Jing | Martins, Marco | Vokonas, Pantel | Gold, Diane R. | Schwartz, Joel | Coull, Brent A. | Koutrakis, Petros
Exposure to traffic-related PM₂.₅ mass and its components can affect human health. Meanwhile, indoor concentrations are better exposure predictors as compared to outdoor concentrations because individuals spend the majority of their time indoors. We estimated the impact of traffic emissions on indoor PM₂.₅ mass and its species as a function of road proximity in Massachusetts. A linear regression model was built using 662 indoor samples and 580 ambient samples. Analysis shows that indoor exposures to traffic-related particles increased dramatically with road proximity. We defined relative concentration decrease, R(α), as the ratio of the indoor concentration at perpendicular distance α in meters from the closest major road to the indoor concentration at 1800 m from the major road. R(13) values for PM₂.₅ mass and Black Carbon (BC) were 1.3 (95%CI: 1.4, 1.6) and 2.1 (95%CI: 1.3, 2.8) for A12 roads, and 1.3 (95%CI: 1.2, 1.4) and 1.2 (95%CI: 1.1, 1.3) for A3 roads. R(α) values were also estimated for Fe, Mn, Mo, Sr and Ti for A12 roads, and Ca, Cu, Fe, Mn, Mo, Ni, Si, Sr, V and Zn for A3 roads. R(α) values for species associated mainly with brakes, tires or road dust (e.g., Mn, Mo and Sr) were higher than others. For A12 roads, R(13) values for Mn and Mo were 10.9 (95%CI: 0.9, 20.9) and 6.5 (95%CI: 1.4, 11.5), and ranged from 1.3 to 2.1 for other species; for A3 roads, R(13) values for Mn, Mo and Sr were 1.9 (95%CI: 1.1, 2.9), 1.8 (95%CI: 1.1, 2.4), and 8.5 (95%CI: 5.9, 10.9), and ranged from 1.2 to 1.6 for others. Our results indicate a significant impact of local traffic emissions on indoor air, which depends on road proximity. Thus road proximity which has been used in many epidemiological studies is a reasonable exposure metric.
اظهر المزيد [+] اقل [-]Comparison of PM2.5 chemical composition and sources at a rural background site in Central Europe between 1993/1994/1995 and 2009/2010: Effect of legislative regulations and economic transformation on the air quality
2018
Pokorná, Petra | Schwarz, Jaroslav | Krejci, Radovan | Swietlicki, Erik | Havránek, Vladimír | Ždímal, Vladimír
From December 1993 to January 1995 and from October 2009 to October 2010, a total of 320 and 365 daily samples of the PM2.5 were collected at a rural background site (National Atmospheric Observatory Košetice) in Central Europe. The PM2.5 samples were analyzed for 29 and 26 elements respectively by Particle-Induced X-ray Emission (PIXE) and water-soluble inorganic ions by Ion Chromatography (IC) in 2009/2010. The Positive Matrix Factorization (PMF) was applied to the chemical composition of PM2.5 to determine its sources. The decreasing trends of almost all elements concentrations, especially the metals regulated by the EU Directive (2004/107/EC) are evident. The annual median ratios indicate a decrease in concentrations of the PM2.5 elements. The slight increase of K concentrations and Spearman's rank correlation coefficient rs 0.09 K/Se points to a rise in residential wood combustion. The S concentrations are nearly comparable (higher mean in 2009/2010, while the annual median ratio is under 1). The five major source types in the mid-1990s were ascribed to brown coal combustion, oil combustion, sea salt and dust – long-range transport, re-suspended dust and black coal combustion. The industrial combustion of brown and/or black coal (rs 0.75 Se/As, rs 0.57 Ga/Ge and rs 0.20 As/Zn) and oil (rs 0.72 V/Ni) of the regional origin dominated. In the 1990s, the potential source regions were the border area of Czech Republic, German and Poland (brown coal), the Moravia-Silesia region at the Czech-Polish border (black coal), and Slovakia, Austria, Hungary, and the Balkans (oil). In 2009/2010, the apportioned sources were sulfate, residential heating, nitrate, industry, re-suspended dust, and sea salt and dust – long-range transport. The secondary sulfate from coal combustion and residential biomass burning (rs 0.96, K/K+) of local origin dominated.The declining trend of the elemental concentrations and change in the source pattern of the regional background PM2.5 in Central Europe between the mid-1990s and 2009/10 reflects the economic transformation and impact of stricter legislation in Central Europe.
اظهر المزيد [+] اقل [-]Enzyme activity indicates soil functionality affectation with low levels of trace elements
2018
Martín-Sanz, Juan Pedro | Valverde-Asenjo, Inmaculada | de Santiago-Martín, Ana | Quintana-Nieto, José Ramón | González-Huecas, Concepción | López-Lafuente, Antonio L. | Diéguez-Antón, Ana
The use of the soil can alter its functionality and influence the (bio)availability of any contaminants present. Our study considers two types of agricultural soils, rainfed and olive soils, managed according to conventional practices that apply contaminants directly to the soil (fertilizers, pesticides, fungicides, etc.) and receive contaminants from the atmosphere (traffic, industry, etc.); and a forest soil that is not subject to these agricultural practices. In this scenario, we consider a mixture of 16 trace elements (As, Ba, Be, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, Sb, Sn, V and Zn), since their interactions with the soil can produce synergistic and/or antagonistic effects that are not considered in most studies. We studied whether the content and (bio)availability of low concentrations of a mixture of trace elements affect the soil functionality in terms of the activity of some key enzymes We analysed the total, potentially and immediately available fractions, the soil parameters and soil enzyme activity. The results show that the functionality of the soils studied was affected despite the low concentrations of trace elements. The highest concentrations of total trace elements and available fractions were found in forest soils compared to the other two uses. Soil enzyme activity is best explained by the potentially available fraction of a mixture of trace elements and physico-chemical soil variables. In our study, pH, total nitrogen, organic carbon and fine mineral particles (silt and clay) had an influence on soil enzyme activity and the (bio)available fractions of trace elements.
اظهر المزيد [+] اقل [-]Characteristics and sources of trace elements in PM2.5 in two megacities in Sichuan Basin of southwest China
2018
Wang, Huanbo | Qiao, Baoqing | Zhang, Leiming | Yang, Fumo | Jiang, Xia
To characterize major trace elements in PM₂.₅ and associated sources in two megacities, Chengdu (CD) and Chongqing (CQ), in Sichuan Basin of southwest China, daily PM₂.₅ samples were collected at one urban site in each city from October 2014 to July 2015 and were analyzed for their contents of thirteen trace elements including four crustal elements (Al, Ca, Fe, and Ti), eight trace metals (K, Cr, Zn, Cu, Mn, Pb, Ni, and V), and As. Multiple approaches including correlation analysis, enrichment factor, principal component analysis, and conditional probability function (CPF) were applied to identify potential sources of these elements. Most of the measured trace elements in Sichuan Basin were found to have lower concentrations than in the other regions of China. K and Fe were the most abundant elements at CD with an annual mean concentrations of 720 ± 357 and 456 ± 248 ng m⁻³, accounting for 34.6% and 21.9% of the total analyzed trace elements, respectively. Ca presented the highest concentration among all of the elements at CQ with annual mean of 824 ± 633 ng m⁻³ (29.1% of the total). Crustal elements had the highest concentrations in spring while heavy metals had distinct seasonal variations typically with the highest concentrations in winter and the lowest in summer. Ti and Al were identified to be primarily from soil while most of the analyzed heavy metals (Cr, Mn, Cu, Zn, Pb, Ni) and As were from anthropogenic sources associated with coal combustion, industrial emission from glassmaking production and iron/steel manufacturing, and non-exhaust vehicle emission.
اظهر المزيد [+] اقل [-]