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Evaluation of highly mobile fraction of trace elements in PM10 collected in Upper Silesia (Poland): Preliminary results Texto completo
2015
Zajusz-Zubek, Elwira | Mainka, Anna | Korban, Zygmunt | Pastuszka, Józef S.
The amount of the soluble fraction of trace elements released from inhaled particulate matter seems to be one of the key factors of the toxicity of these particles. This study reports the concentrations of PM10 and trace elements in total and water-soluble fractions (bioavailable form). Weekly samples were collected at two rural sites in Upper Silesia, Poland. Measurements were carried out from April to August 2013, divided between heating and non-heating sessions. During heating sessions, the concentrations of PM10 in selected sites varied in the range of 32.88–48.70 μg m−3, while for the non-heating sessions the range was 16.14–27.89 μg m−3.Selected PM10 samples (characteristic for both sessions) were determined by means of total and water-soluble content of eight trace elements. The elements are characteristic of carcinogenic (As, Cr, Cd and Ni), probably carcinogenic (Co and Pb) and toxic (Mn and Sb) groups. The analyses of the mineralized samples as well as the water-soluble fractions were carried out by ICP-MS method using a Varian 810 MS.The total concentration of carcinogenic Cd, Cr and Ni during non-heating sessions was 2.81, 7.97 and 4.82 ng m−3, respectively. While during heating sessions the total content was twice as high. Similar relation was observed for the concentration of PM10. The concentration of the soluble fraction of these elements in the atmospheric air in heating sessions was 1.62, 0.75, 2.20, 1.79, 1.85 ng m−3 for As, Cr, Pb, Mn, Sb, respectively and remained almost the same as in non-heating sessions. Lower levels of Ni and Cd (0.15 and 0.11 ng m−3) were determined during heating sessions. The obtained data indicate that during heating periods these elements are probable present mainly in other fractions with lower mobility, so less harmful to human health.
Mostrar más [+] Menos [-]n-Alkanes and stable C, N isotopic compositions as identifiers of organic matter sources in Posidonia oceanica meadows of Alexandroupolis Gulf, NE Greece Texto completo
2015
Apostolopoulou, Maria-Venetia | Monteyne, Els | Krikonis, Konstantinos | Pavlopoulos, Kosmas | Roose, Patrick | Dehairs, Frank
We analyzed n-alkane contents and their stable carbon isotope composition, as well as the carbon and nitrogen isotope composition (δ13C, δ15N) of sediment organic matter and different tissues of Posidonia oceanica seagrass sampled in Alexandroupolis Gulf (A.G.), north-eastern Greece, during 2007–2011. n-Alkane contents in P. oceanica and in sediments showed similar temporal trends, but relative to bulk organic carbon content, n-alkanes were much more enriched in sediments compared to seagrass tissue. Individual n-alkanes in sediments had similar values than seagrass roots and rhizomes and were more depleted in 13C compared to seagrass leaves and sheaths, with δ13C values ranging from −35‰ to −28‰ and from −25‰ to −20‰, respectively. n-Alkane indexes such as the Carbon Preference Index, carbon number maximum, and n-alkane proxy 1 (C23+C25/C23+C25+C29+C31) indicate strong inputs of terrestrial organic matter, while the presence of unresolved complex mixtures suggests potential oil pollution in some sampled areas.
Mostrar más [+] Menos [-]Influence of El Niño Southern Oscillation phenomenon on coastal phytoplankton in a mixohaline ecosystem on the southeastern of South America: Río de la Plata estuary Texto completo
2015
Sathicq, María Belén | Bauer, Delia Elena | Gómez, Nora
The aim of this study was to analyze the density, diversity, biomass and assemblage composition of the phytoplankton in relation to environmental conditions (physical, chemical, hydrological and meteorological variables), measured under the different scenarios caused by the ENSO phenomenon in the period between 2005 and 2012, in six sampling sites in the tidal freshwater zone of the Río de la Plata estuary, covering almost 100km of coastline. The results revealed changes in the structure of the phytoplankton, such as a significant reduction of diversity, and decreases in biomass and phytoplankton density, particularly during El Niño phases. Cyanobacteria were more abundant in the neutral periods, Chlorophyceae dominated La Niña phase while Bacyllariophyceae dominated El Niño. However, no complete replacement of species between cycles was observed. The results obtained were highly variable due to the inherent natural variability of the Río de la Plata, emphasized by the anthropogenic impact in this area.
Mostrar más [+] Menos [-]Exposure from particle and ionic contamination to children in schools of India Texto completo
2015
Habil, Mahima | Massey, David D. | Taneja, Ajay
The high levels of indoor particulate matter in developing countries and the apparent scale of its impact on the global burden of disease underline the importance of particulate matter as an environmental health risk and the consequent need for monitoring them particularly in indoor school microenvironments. The concentrations of PM10, PM2.5, and PM1.0, were measured along with ionic concentrations K+, Ca2+, Na+, Mg2+, SO42–, NO3–, Cl– and F– collected from settled dust in the indoor–outdoor environment of roadside and residentially located schools in Agra City, from January to May 2008–09. Along with PM concentrations at the roadside and residentially located schools meteorological parameters like temperature, humidity, and wind speed and air exchange rate was also calculated during the study period. The enrichment factor was calculated using Ca as a reference to the trace ionic species to identify the sources. Principle component analysis showed three to two factors inside and three factors outside the classrooms of the roadside and residentially located schools. These factors reflected sources like soil dust, road dust, vehicle emissions, anthropogenic sources, industrial emissions, metal processes, and incineration activities and their contributions were estimated using principal component analysis. Symptoms like asthma, dizziness, coughing, itching, eye irritation, shortness of breath, headache, cold and flu were observed. Measurements of such exposure levels would be helpful in the prevention of environmental risks to school children.
Mostrar más [+] Menos [-]Assessing water quality by ratio of the number of dominant bacterium species between surface/subsurface sediments in Haihe River Basin Texto completo
2015
Ke, Xin | Wang, Chunyong | Jing, Debing | Zhang, Yun | Zhang, Haijun
Sedimentary microorganisms can be used as a sensitive indicator of integrated aquatic environment quality assessment and indicate long-term water quality or toxicity. According to the Chinese National Standards of GB 3838-2002 and GB 18918-2002, the comprehensive water quality in Haihe River Basin has been described. Results showed that the comprehensive water quality in 6 sites, 4 sites, and 20 sites were good, bad, and medium. Furthermore, 162 dominant bacterial species were identified in surface and subsurface sediments in the 30 sampling sites. As revealed by two initial models constructed by logistic regression, the comprehensive water quality exhibited a pattern from good to bad as the ratio of the number of dominant bacterial species in surface sediments to that in subsurface sediments increased from 1 to 2.1. This finding possibly bridged a traditional gap between aquatic microbe indicators and water quality assessment or monitoring techniques.
Mostrar más [+] Menos [-]Concentrations of trace elements in a rare and threatened coastal shark from the Arabian Gulf (smoothtooth blacktip Carcharhinus leiodon) Texto completo
2015
Moore, Alec B.M. | Bolam, Thi | Lyons, Brett P. | Ellis, Jim
Kuwait’s waters are one of only two locations where the smoothtooth blacktip shark Carcharhinus leiodon is known to occur. Concentrations of 11 trace elements were analysed in five juvenile and two adult specimens of this coastal predator. Concentrations of lead in muscle increased with length, whilst manganese concentration decreased. Arsenic concentrations in muscle were among the highest reported in elasmobranchs, and the concentration in the liver increased significantly in relation to length. In comparison to published literature, concentrations of manganese (liver), lead (muscle) and iron (muscle and liver) were high. Mercury concentrations in the muscle exceeded European Food Safety Authority limits and were among the highest reported in any elasmobranch. Concentrations of selenium, which may inhibit mercury toxicity, were also high. These results and previous studies indicate that potentially hazardous levels of mercury and other contaminants may occur in sharks in this region, adding further stressors to these vulnerable populations.
Mostrar más [+] Menos [-]Concentrations of carbon monoxide in indoor and outdoor air of Ghalyun cafes Texto completo
2015
Fazlzadeh, Mehdi | Rostami, Roohollah | Hazrati, Sadegh | Rastgu, Ali
Indoor and outdoor carbon monoxide (CO) concentrations were measured in 68 Ghalyun cafes in Ardabil City of Iran. One hour sampling was performed in each location and hourly mean concentrations were reported. Respective mean concentrations of CO in indoor and outdoor air were 24.75±17.17 and 2.65±1.33 ppm with an average indoor to outdoor air concentration ratio of 13.3±13.1. Within the variables studied; type of the tobacco smoked, location of the cafe inside the building, and utilizing mechanical ventilator, respectively, were recognized as the most influential factors controlling CO concentrations in Ghalyun cafes (p<0.05). 73.5% of workers (27.3 and 95.7% of cafes located on ground floors and basements, respectively) were exposed to higher levels of CO than the corrected OEL–TWA (Occupational Exposure Limit) of 10.4 ppm.
Mostrar más [+] Menos [-]Temporal and spatial distribution of tropospheric NO2 over Northeast Asia using OMI data during the years 2005–2010 Texto completo
2015
Kim, Deok–Rae | Lee, Jae–Bum | Keun Song, Chang | Kim, Seung–Yeon | Ma, Young–ll | Lee, Kyung–Mi | Cha, Jun–Seok | Lee, Sang–Deok
This study aimed to examine the main characteristics of tropospheric nitrogen dioxide (NO2) concentrations over the Northeast Asia, using the Ozone Monitoring Instrument (OMI) data from 2005 to 2010. The annual mean NO2 concentrations (AMNC) had an increasing trend mainly due to increasing NO2 emissions in China except during the 2008 Beijing Olympic Games period, while the reduction policies of South Korea and Japan have led it to be stagnant or decreased. To investigate further regional characteristics of NO2 increasing trends in China, we divided our study area into 6 geographical regions (sectors 1–6) and then considering 4 different socio–economic levels (groups 1–4) among main cities in Eastern regions (sector 2 and 4) where the concentrations level is the highest in China and NO2 concentrations show continued increasing trend. Especially OMI NO2 and emissions consistently showed that metropolitan/big—sized and developed cities (group 1), such as Beijing and Shanghai, had an increasing trend of NO2 concentrations until 2007 and decreasing thereafter, while small/mid–sized and developing cities (groups 2 and 3) kept a continuous increasing trend over all periods. The seasonal change in NO2 concentrations showed the apparent increasing trend in winter and no significant trend in summer in all groups except for group 1. These results indicate that an increase in AMNC in Northeast Asia was mainly attributed to the increasing NO2 concentrations in winter in groups 2 and 3. Therefore, it strongly suggests the importance of the NO2 management for groups 2 and 3 to improve air quality in the Northeast Asia.
Mostrar más [+] Menos [-]Human impact on atmospheric precipitation in a protected area in Western Poland. Results of long–term observations: Concentrations, deposition and trends Texto completo
2015
Walna, Barbara
The paper presents the results of long–term measurements of rain chemistry in the woodland area of the Wielkopolski National Park (Western Poland) experiencing some human impact. The ions predominating in precipitation turned out to be those of ammonium and sulfates, which is indicative of human impact related with agriculture and animal breeding as well as with SO2 emissions. In the period 2002–2013 it is possible to identify, for both precipitation and throughfall, statistically significant decreasing trends in the concentrations and deposition of sulfates, ammonium and potassium, and an increasing trend for fluoride. Both bulk deposition and throughfall of N was higher than that of S. The deposition of nitrogen with throughfall was near to the critical load. High levels of acid–forming ions were observed in both, the winter and late–spring seasons, which proves not only the impact of heating but also of the local industry. Notable is the simultaneous occurrence of extremely high levels of acid–forming ions in some precipitation events, which might have many important implications for the soil, water and biota. There was a change in the pattern of atmospheric chemistry observed as a statistically significant downward trend in the rates of ionic concentration equivalents.
Mostrar más [+] Menos [-]Atmospheric levels and health risk of polycyclic aromatic hydrocarbons (PAHs) bound to PM2.5 in Guangzhou, China Texto completo
2015
Liu, Jingjing | Man, Ruilin | Ma, Shexia | Li, Juansheng | Wu, Qi | Peng, Juanying
The polycyclic aromatic hydrocarbons (PAHs) in PM2.5 contribute significantly to health risk. The objectives of this study were to assess the occurrence and variation in the concentrations and sources of PM2.5-bound PAHs sampled from the atmosphere of a typical southeastern Chinese city (Guangzhou) from June 2012 to May 2013, with the potential risks being investigated. The annual average concentration of PM2.5 was 64.88μgm−3. The annual average concentration of PAHs in PM2.5 was 33.89ngm−3. Benzo(a)pyrene (BaP) was found to be the predominant PAH in all PM2.5 samples throughout the year, constituting approximately 8.78% of the total PAH content. The significant meteorological parameters for most of the PAHs were sunshine time, air pressure, and humidity, together representing 10.7–52.4% of the variance in atmospheric PAH concentrations. Motor-vehicle exhaust and coal combustion were probably the main sources of PAHs in PM2.5 in Guangzhou. The average inhalation cancer risk (ICR) for a lifetime of 70years was 5.98×10−4 (ranging from 8.39×10−5 to 1.95×10−3).
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