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Sedimentology and geochemistry of mud volcanoes in the Anaximander Mountain Region from the Eastern Mediterranean Sea Texte intégral
2015
Talas, Ezgi | Duman, Muhammet | Küçüksezgin, Filiz | Brennan, Michael L. | Raineault, Nicole A.
Investigations carried out on surface sediments collected from the Anaximander mud volcanoes in the Eastern Mediterranean Sea to determine sedimentary and geochemical properties. The sediment grain size distribution and geochemical contents were determined by grain size analysis, organic carbon, carbonate contents and element analysis. The results of element contents were compared to background levels of Earth’s crust. The factors that affect element distribution in sediments were calculated by the nine push core samples taken from the surface of mud volcanoes by the E/V Nautilus. The grain size of the samples varies from sand to sandy silt. Enrichment and Contamination factor analysis showed that these analyses can also be used to evaluate of deep sea environmental and source parameters. It is concluded that the biological and cold seep effects are the main drivers of surface sediment characteristics from the Anaximander mud volcanoes.
Afficher plus [+] Moins [-]Interpretation of coastal sediment quality based on trace metal and PAH analysis, benthic foraminifera, and toxicity tests (Sardinia, Western Mediterranean) Texte intégral
2015
Schintu, Marco | Buosi, Carla | Galgani, François | Marrucci, Alessandro | Marras, Barbara | Ibba, Angelo | Cherchi, A. (Antonietta)
An integrated approach for the assessment of coastal sediment quality was utilised in three areas of Sardinia (Western Mediterranean, Italy). Sediments were analysed for trace metals and polycyclic aromatic hydrocarbons (PAHs), while benthic foraminifera were used as bioindicators. Furthermore, the embryo-toxicity test was used to provide ecologically relevant information using rapid and cost-effective screening tools. The aim was to evaluate the usefulness of coupling different analytical tools. The results revealed the presence of polluted sediments in areas exposed to petrochemical industries, smelters or military settlements. However, while foraminifera have presented similar indications for chemical analysis of contamination levels in the different areas, the toxicity test exhibited a poor relationship with the contaminants measured individually. The results raise questions concerning the bioavailability of contaminants released by sediments in the water column. Overall, the toxicity rate was significant in many samples in comparison with other sites studied in other Mediterranean regions.
Afficher plus [+] Moins [-]Distribution of butyltins and alternative antifouling biocides in sediments from shipping and shipbuilding areas in South Korea Texte intégral
2015
Kim, Nam Sook | Hong, Sang Hee | An, Joon Geon | Shin, Kyung-Hoon | Shim, Won Joon
The occurrence and distribution of tributyltin (TBT) and alternative biocides were investigated in sediment from semi-enclosed bays, fishing ports, and large commercial harbors in Korea. Extremely high concentration of TBT (55,264ngSn/g) was detected near a large shipyard, even after a total ban on its use in Korea. Diuron was the biocide with the highest detection frequency and concentration levels, followed by Irgarol 1051. Sea-Nine 211 was detected at 3 of 32 stations surveyed. Dichlofluanid, zinc and copper pyrithiones levels were below the detection limits at all the stations surveyed. The relatively high levels of Diuron (9–62.3ng/g) and Irgarol 1051 (1.5–11.5ng/g) were detected in harbor and shipyard areas. Diuron and Irgarol 1051 levels including TBT in sediments from hot spots in Korea exceeded global sediment quality guidelines.
Afficher plus [+] Moins [-]Evaluation of the relationship between allergic diseases in school children at Seoul's roadside elementary schools and air pollution Texte intégral
2015
Lee, Chungsoo | Kim, Hohyun | Lim, Youngwook | Yang, Jiyeon | Yu, Seungdo | Lee, Jungsub | Chang, Junyoung | Son, Hyerim | Park, Jungwon | Shin, Dongchun
An elementary school is an important public place for children and it is where they spend most of their days. The objective of this study was to survey the environmental conditions at schools and to assess the relationship between air pollution and allergic diseases using the International Study of Asthma and Allergies in Childhood questionnaire. Nine elementary schools were selected and subsequently classified into three groups. The selection included two schools with no traffic-related or other pollutants, four schools situated near roads with six lanes, and three schools situated near beltways. Allergic diseases were assessed in a total of 6301 students. School zones with critical exposure to pollutants were selected within each school and were evaluated based on the levels of particulate matter, fine particulate matter, ozone, carbon monoxide, carbon dioxide, nitrogen dioxide, sulfur dioxide and black carbon. O3 and PM10 exposures were significantly associated with the prevalence of lifetime symptoms and diagnosis of asthma. O3 and PM10 exposures were also associated with lifetime symptoms, diagnosis, and 1-year physician diagnosis prevalence of allergic rhinitis. BC exposure was significantly associated with the rates of 1-year treatment of disease for allergic rhinitis. For schools located near sources of air pollution, the prevalence of lifetime symptoms for atopic dermatitis was significantly increased. Some symptoms of allergies were significantly increased at schools surrounded by a higher traffic volume. This study provides additional evidence that exposure to school zone air pollutants and traffic volume put school children at risk for childhood allergic diseases. Thus, strategies and actions are necessary to protect children in schools from exposure to environmental pollutants. In addition, future analysis to evaluate the relationship between traffic-related air pollution and the development of allergic diseases at more advanced ages are needed to confirm or refute these associations.
Afficher plus [+] Moins [-]Determinants on ambient PM2.5 infiltration in non-heating season for urban residences in Beijing: Building characteristics, interior surface coverings and human behavior Texte intégral
2015
Huang, Lihui | Hopke, Philip K. | Zhao, Weiping | Li, Mu
Ambient fine particulate matter (PM2.5) pollution is currently a major public health concern in Chinese urban areas. However, assessment of ambient PM2.5 exposure and its health effects is challenging in China because the exposure primarily occurs indoors. There is large inter-home variability of the fraction of ambient PM2.5 that penetrates indoors and remains airborne (Finf), and the factors influencing this variability are unknown. In this study, 24-h real-time indoor and outdoor PM2.5 mass concentrations were concurrently collected for 41 urban residences in the non-heating season. The Finf were estimated with steady-state and dynamic models derived from mass balance considerations. Multivariate statistical analyses were employed to examine the associations between Finf and 78 factors related to building characteristics, motor vehicle traffic, human behavior, meteorology, furnishings, and atmospheric/indoor chemistry. The estimate of Finf over the 24-h monitoring period with the steady-state model was 0.72 ± 0.01; the Finf estimate for single residences, using the dynamic model, were 0.59 ± 0.13 (N = 33). Two predictive models for Finf were constructed with categorical and numerical variables, respectively. The results revealed that building characteristics, traffic, wall and floor coverings, and human behavior had substantial influence on Finf in the non-heating season. The variance contributions of the determinants of traffic, wall and floor coverings, and human behavior were comparable to or even greater than those of the building characteristics.
Afficher plus [+] Moins [-]Clam predator protection is effective and necessary for food production Texte intégral
2015
Shellfish aquaculture is a widely practiced way of producing food for human consumption in coastal areas. When farming intertidal clams, farmers commonly protect young seedling clams from predatory losses by covering farmed plots with netting or screening. Recent discussion of the effectiveness of protective nets or screens and their environmental effects has raised questions concerning the utility of the practice. We provide data based on a review of more than 35 peer-reviewed articles, as well as our own research that demonstrates the efficacy of predator protection for clam farms in various habitats around the world. In addition, we evaluate the effects of screening on temperature, and comment on ancient practices of clam gardening as conducted in the Pacific Northwest.
Afficher plus [+] Moins [-]A review of standards and guidelines set by international bodies for the parameters of indoor air quality Texte intégral
2015
Abdul–Wahab, Sabah Ahmed | Chin Fah En, Stephen | Elkamel, Ali | Ahmadi, Lena | Yetilmezsoy, Kaan
Standards and guidelines as defined by various international agencies are employed by the researchers to evaluate an acceptable quality of air in indoor as well as outdoor environments. The main objective of this paper is to establish a comprehensive review of Indoor Air Quality (IAQ) guidelines and other standard values that are implemented currently. For this purpose, the present study summarizes the main standards and guidelines related to key indoor air pollutants and levels of thermal comfort developed by different agencies around the world. These agencies and organizations include the American Society of Heating, Refrigerating and Air– Conditioning Engineers (ASHRAE), the Hong Kong Environmental Protection Department (HKEPD), the World Health Organization (WHO), and the National Health and Medical Research Council (NHMRC) of Australia. Common indoor air pollutants that are found to frequently affect indoor populations are, carbon dioxide (CO2), nitrogen dioxide (NO2), formaldehyde (HCHO), carbon monoxide (CO), sulfur dioxide (SO2), and particulate matter in sizes <2.5 and 10 μm (PM2.5 and PM10, respectively). Other factors that affect IAQ are the moisture content of the air (i.e., relative humidity), the temperature of the indoor air, and the air speed or movement. Sick building syndrome (SBS) describes the various interactions between these major pollutants and factors of IAQ that cause adverse health effects on humans. In addition, this paper reviews various stipulated guidelines that are implemented by the relevant regulatory institutions and agencies to prevent SBS.
Afficher plus [+] Moins [-]Sampling frequency of ciliated protozoan microfauna for seasonal distribution research in marine ecosystems Texte intégral
2015
Xu, Henglong | Yong, Jiang | Xu, Guangjian
Sampling frequency is important to obtain sufficient information for temporal research of microfauna. To determine an optimal strategy for exploring the seasonal variation in ciliated protozoa, a dataset from the Yellow Sea, northern China was studied. Samples were collected with 24 (biweekly), 12 (monthly), 8 (bimonthly per season) and 4 (seasonally) sampling events. Compared to the 24 samplings (100%), the 12-, 8- and 4-samplings recovered 94%, 94%, and 78% of the total species, respectively. To reveal the seasonal distribution, the 8-sampling regime may result in >75% information of the seasonal variance, while the traditional 4-sampling may only explain <65% of the total variance. With the increase of the sampling frequency, the biotic data showed stronger correlations with seasonal variables (e.g., temperature, salinity) in combination with nutrients. It is suggested that the 8-sampling events per year may be an optimal sampling strategy for ciliated protozoan seasonal research in marine ecosystems.
Afficher plus [+] Moins [-]Modeling the dispersion of viable and total Escherichia coli cells in the artificial semi-enclosed bathing area of Santa Marinella (Latium, Italy) Texte intégral
2015
Bonamano, S. | Madonia, A. | Borsellino, C. | Stefanì, C. | Caruso, G. | De Pasquale, F. | Piermattei, V. | Zappalà, G. | Marcelli, M.
Coastal areas are strongly affected by episodes of fecal contamination due to polluted water inflows from inadequately treated sewages. The present study aims to investigate the dispersion of Escherichia coli in the artificial semi-enclosed bathing area of Santa Marinella (Latium, Italy) through in situ samplings carried out in summer 2012 and the application of a dynamic model. Collected samples were analyzed by the Culture-Based technique and the Fluorescent Antibody method in order to estimate both the viable culturable cells and the total E. coli population, respectively. The in situ datasets were used to test the proposed modeling approach and simulate the behavior of bacteria as particles subjected, or not, to decay. Next, the flushing time and the computation of the Microbiological Potential Risk Area allowed the evaluation of the contribution of physical and biological processes to coliform dispersion and the related potential risk for bathers.
Afficher plus [+] Moins [-]Soil Pollution Due to Irrigation with Arsenic-Contaminated Groundwater: Current State of Science Texte intégral
2015
Gillispie, Elizabeth C. | Sowers, Tyler D. | Duckworth, Owen W. | Polizzotto, Matthew L.
Food with elevated arsenic concentrations is becoming widely recognized as a global threat to human health. This review describes the current state of knowledge of soil pollution derived from irrigation with arsenic-contaminated groundwater, highlighting processes controlling arsenic cycling in soils and resulting arsenic impacts on crop and human health. Irrigation practices utilized for both flooded and upland crops have the potential to load arsenic to soils, with a host of environmental and anthropogenic factors ultimately determining the fate of arsenic. Continual use of contaminated groundwater for irrigation may result in soils with concentrations sufficient to create dangerous arsenic concentrations in the edible portions of crops. Recent advances in low-cost water and soil management options show promise for mitigating arsenic impacts of polluted soils. Better understanding of arsenic transfer from soil to crops and the controls on long-term soil arsenic accumulation is needed to establish effective arsenic mitigation strategies within vulnerable agronomic systems.
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