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Öğe Effect of exhaust gas on corrosion of metals(Gordon and Breach Science Publishers, 1998) Ornektekin, SerminThe corrosion effect of exhaust gases expelled from petroleum vehicles on several metals, such as iron, copper, aluminium and galvanized iron sheet was investigated. The investigations were carried out on the number of vehicles and time dependency. For this purpose, a test cell through which the exhaust gases passed directly was developed. The corrosion process on the above mentioned metals was investigated. A parallel test was made with the same elements in an atmosphere free of exhaust gases. The corrosion products formed on the surfaces of material samples were identified as mass loss by atomic absorption spectroscopy (AAS). From the solution formed by exhaust gases pH, lead amount and % compositions of exhaust gases were measured and relative humidity was observed. The surface films of corroded metals were also taken with a metal microscope. According to the experimental results, it was observed that the exhaust gases increased the galvanized iron corrosion rate. This increase occurred most on iron materials, less in galvanized iron ones and the least in copper containing ones.Öğe Effects of air pollution on lung function and symptoms of asthma, rhinitis and eczema in primary school children(Springer Heidelberg, 2013) Altug, Hicran; Gaga, Eftade O.; Dogeroglu, Tuncay; Ozden, Ozlem; Ornektekin, Sermin; Brunekreef, Bert; Meliefste, KeesHealth effects of ambient air pollution were studied in three groups of schoolchildren living in areas (suburban, urban and urban-traffic) with different air pollution levels in EskiAYehir, Turkey. This study involved 1,880 students aged between 9 and 13 years from 16 public primary schools. This two-season study was conducted from January 2008 through March 2009. Symptoms of asthma, rhinitis and eczema were determined by the International Study of Asthma and Allergies in Childhood questionnaire in 2008. Two lung function tests were performed by each child for summer and winter seasons with simultaneous ambient air measurements of ozone (O-3), nitrogen dioxide (NO2) and sulfur dioxide (SO2) by passive sampling. Effects of air pollution on impaired lung function and symptoms in schoolchildren were estimated by multivariate logistic regression analyses. Girls with impaired lung function (only for the summer season evaluation) were more observed in suburban and urban areas when compared to urban-traffic area ([odds ratio (OR) = 1.49; 95 % confidence interval (CI) 1.04-2.14] and [OR = 1.69 (95 % CI 1.06-2.71)] for suburban vs. urban-traffic and urban vs. urban-traffic, respectively). Significant association between ambient ozone concentrations and impaired lung function (for an increase of 10 mu g m(-3)) was found only for girls for the summer season evaluation [OR = 1.11 (95 % CI 1.03-1.19)]. No association was found for boys and for the winter season evaluation. No association was found between any of the measured air pollutants and symptoms of current wheeze, current rhinoconjunctivitis and current itchy rash. The results of this study showed that increasing ozone concentrations may cause a sub-acute impairment in lung function of school aged children.Öğe Investigation of Soil Concentrations of Persistent Organic Pollutants, Trace Elements, and Anions Due to Iron-Steel Plant Emissions in an Industrial Region in Turkey(Springer International Publishing Ag, 2010) Odabasi, Mustafa; Bayram, Abdurrahman; Elbir, Tolga; Seyfioglu, Remzi; Dumanoglu, Yetkin; Ornektekin, SerminThe spatial distribution of several air pollutants emitted from iron-steel industries in Hatay-Iskenderun industrial region in Turkey was investigated by measuring their concentrations in soil. Collected soil samples (n = 20) were analyzed for persistent organic pollutants (POPs; i.e., polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polybrominated diphenyl ethers, and polychlorinated naphthalenes), anions, and trace elements. Generally, all measured POP concentrations and marker trace elements for iron-steel industry (Zn, Pb, and Cu) were high relative to those reported previously for rural and urban areas around the world, and they were comparable to those measured recently in a similar industrial region (Aliaga, Izmir, Turkey). For all investigated POPs, elements, and anions, the highest concentrations were measured at points located north of the iron-steel industries where their emissions are transported by the prevailing southerly winds. The spatial distribution and levels of POPs, elemental, and anionic concentrations indicated that the iron-steel plants in Hatay-Iskenderun region are important sources for these pollutants. Statistically significant relationships between several organic and inorganic pollutants further confirmed that they are emitted by common sources (iron-steel plants).Öğe Precipitation chemistry as an indicator of urban air quality in mersin, north-eastern mediterranean region(Springer, 2008) Ozsoy, Turkan; Turker, Pelin; Ornektekin, SerminThe chemical composition of precipitation in the city of Mersin on the Mediterranean coast of Turkey has been studied. Spatial and temporal variability of rainwater constituents have been determined from samples collected at two central and two suburban stations for the December 2003-May 2005 period. A total of 246 samples covering all precipitation events were analyzed to determine pH, conductivity, as well as major anion (Cl-, NO3-, SO42-); major cation (H+, Na+, K+, Ca2+, Mg2+, NH4+) and formaldehyde (HCHO) concentrations. The pH varied within a range of 4.8-8.5, with only 8 out of 246 samples being acidic (pH<5.6), and the remaining highly alkaline samples being neutralized by either NH4+ in rainwater, or by CaCO3 resulting from wet deposition of atmospheric dust. The volume weighted mean Sigma Anion/Sigma Cation ratio was 0.49. The equivalent concentration of major ionic species followed the order: Ca2+ > HCO3- > SP42- > Cl- > NH4+ > Na+ > Mg2+ > NO3- > K+ > H+. Formaldehyde concentrations varied in the range of 0.01-17.9 mu M, and was found to be dependent on precipitation volume. Relatively higher NH4+, SO42-, NO3- and HCHO concentrations, mainly of anthropogenic origin, measured near the city center suggest increased pollution from local anthropogenic sources, e.g., residential heating, industrial and/or traffic emissions. In general, the results of this study suggest local precipitation chemistry is more strongly influenced by natural (mineral dust and marine) sources compared to anthropogenic ones.Öğe Trace elements in urban and suburban rainfall, Mersin, Northeastern Mediterranean(Elsevier Science Inc, 2009) Ozsoy, Turkan; Ornektekin, SerminSpatial/temporal variabilities of rainwater constituents are examined based on soluble/insoluble trace elements, pH and electrical conductivity measurements in rainfall sampled during December 2003-May 2005 at two urban and two suburban sites in Mersin, an industrialized city of 850,000 inhabitants on the southern coast of Turkey. In the analyses, backward air mass trajectories for rainy days were used in addition to factor analyses, enrichment factors, phase distributions and correlations between trace elements. The pH varied from 4.8 to 8.5 with an average value of 6.2, reflecting a mainly alkaline regime. Mean concentrations of trace elements collected from urban and suburban sites are spatially variable. Based on the overall data, total concentrations of trace elements were ordered as Ca>Na>Fe>Al>Mg>K>Zn>Mn>Sr>Pb>Ni>Cr>Ba>Cu>Co>Cd. Mainly terrigeneous (Ca, Fe, Al) and, to a lesser extent, sea salt particles (Na, Mg) were shown to be the major source of trace elements. Excluding major cations, the solubilities of trace elements were found to be ordered as Sr>Zn>Ba>Mn>Cu>Ni>Cr>Fe>Al, confirming the lower solubility of crustal elements. Cd, Co and Pb were excluded from the above evaluation because of the low numbers of soluble samples allowing quantitative measurements. The solubilities of Al. Fe, Mn and particularly of Ni were found to be considerably lower than those reported for various sites around the world, most likely due to the effect of pH. During the entire sampling period, a total of 28 dust transport episodes associated with 31 red rain events were identified. Extremely high mean concentration ratios of Al (8.2), Fe (14.4) and Mn (13.1) were observed in red rain, compared to normal rain. The degree of this enhancement displayed a decrease from crustal to anthropogenic origin elements and the lowest enhancements were found for anthropogenic origin elements of Zn and Cd (both having a ratio of 1.1). Aerosol dust was found to be the main source of almost all analyzed elements in Mersin precipitation, regardless that they are crustal or anthropic derived elements. The magnitude of crustal source contribution to trace element budget of precipitation was at its highest levels for crustal originated elements, most probably due to much higher scavenging ratios of crustal elements compared to anthropogenic ones. (C) 2009 Elsevier B.V. All rights reserved.
