Characterization of Volatile Organic Compounds (VOCs) and Their Sources in the Air of Izmir, Turkey

Air samples were collected in Izmir, Turkey at two (suburban and urban) sites during three sampling programs in 2002 and 2004 to determine the ambient concentrations of several monoaromatic, chlorinated and oxygenated volatile organic compounds (VOCs). Samples were analyzed for 60 VOCs using gas chromatography/mass spectrometry and 28 compounds were detected in most samples. On the average, urban air VOC concentrations were about four times higher than those measured at the suburban site. Toluene (40.6%) was the most abundant compound in suburban site and was followed by benzene (7.4%), o,m-xylene (6.5%), and 1,2-dichloroethane (5.1%). In urban site, toluene (30.5%), p-xylene (14.9%), o,m-xylene (11.4%), and ethyl benzene (7.2%) were the dominating compounds in summer. In winter, toluene (31.1%), benzene (23.9%), 1,2-dichloroethane (9.5%), and o,m-xylene (8.2%) were the most abundant compounds. Receptor modeling (positive matrix factorization) has been performed to estimate the contribution of specific source types to ambient concentrations. Six source factors (gasoline vehicle exhaust, diesel vehicle exhaust+residential heating, paint production/application, degreasing, dry cleaning, and an undefined source) were extracted from the samples collected in the urban site. Three source factors (gasoline vehicle exhaust, diesel vehicle exhaust, and paint production/application) were identified for the suburban site.     

Determination of Henry’s Law Constant of Formaldehyde as a Function of Temperature: Application to Air–Water Exchange in Tahtali Lake in Izmir, Turkey

The Henry's law constant (H) is an important parameter in predicting the transport, behavior and fate of organic compounds in environment. H is also required to model the air-water exchange of chemicals. Henry's law constant of formaldehyde (HCHO) was determined at six temperatures (50, 40, 30, 20, 10, and 5 degrees C) using a bubble-column technique. The apparent Henrys law constant (H*) values were strongly correlated to inverse of temperature (1/T, K) and the following relationship was obtained: In H* = (-1,641.3/T)-3.089. Seven concurrent ambient air and aqueous samples were also collected between October 11-17, 2005 at a sampling site located on the shoreline of Tahtali dam Lake in Izmir, Turkey to determine the magnitude and direction (deposition or gas-out) of HCHO flux. In all cases, the modeled gas-phase flux was positive (average +/- SD, 3,181 +/- 408 microg m(-2) day(-1)) indicating that atmospheric HCHO deposited to the Tahtali Lake.     

Using landsat data to determine land use/land cover changes in Samsun, Turkey

The rapid industrialization and urbanization of an area require quick preparation of actual land use/land cover (LU/LC) maps in order to detect and avoid overuse and damage of the landscape beyond sustainable development limits. Remote sensing technology fits well for long-term monitoring and assessment of such effects. The aim of this study was to analyze LU/LC changes between 1980 and 1999 in Samsun, Turkey, using satellite images. Three Landsat images from 1980, 1987 and 1999 were used to determine changes. A post classification technique was used based on a hybrid classification approach (unsupervised and supervised). Images were classified into six LU/LC types; urban, agriculture, dense forest, open forest-hazelnut, barren land and water area. It is found that significant changes in land cover occurred over the study period. The results showed an increase in urban, open forest/hazelnut, barren land and water area and a decrease in agriculture and dense forest in between 1980 and 1999. In this period, urban land increased from 0.77% to 2.47% of the total area, primarily due to conversions from agricultural land and forest to a lesser degree. While the area of dense forest decreased from 41.09% to 29.64% of the total area, the area of open forest and hazelnut increased from 6.73% to 11.88%.     

Ambient concentrations and source apportionment of PCBs and trace elements around an industrial area in Izmir, Turkey

Atmospheric concentrations of polychlorinated biphenyls (PCBs) and trace elements were measured at two sites (Industrial and Urban) located around the Aliaga industrial region, Izmir, Turkey. Average sigma 36PCB concentrations were 3136+/-824 and 1371+/-642 pg m(-3) for summer and winter periods, respectively in the Industrial site and they were 314+/-129 and 847+/-610 pg m(-3) in the Urban site. The elemental content showed that the PM(10) measured at the Industrial site was dominated by terrestrial elements and trace elements emitted by the iron-steel plants (Fe, Zn and Pb). The elemental profile at the Urban site was typical for Aegean Region that was dominated by terrestrial elements (Ca, Al, Mg) and sea salt (Na). Sources of particle-phase PCBs and trace elements were identified using factor analysis (FA) and were apportioned by chemical mass balance (CMB) model. FA suggested that the steel industry, fuel oil combustion, or the nearby vinyl chloride process in the petrochemical plant, and soil were significant PCB sources. CMB results showed that at the Industrial site, the contribution of steel industry and soil to particle-phase PCBs were 71% and 22%, respectively, while at the Urban site, the contributions were 33% and 49%, respectively. Steel industry was also the dominant contributor for trace elements around the site. Fugacity calculations in air and soil showed that the soil acts as a secondary source to the atmosphere for low molecular weight PCBs especially in summer and as a sink for the higher molecular weight ones.     

Airborne pollen in European and Asian parts of Istanbul

Pollen concentrations in the atmosphere of Istanbul, a city located between two continents, has been monitored for 1 year as part of a larger research program. The sampling sites were located in two different continents: the Asian part (AS) and the European part (EP). The sampling was performed in AS and EP of the city by using Hirst type volumetric method, and pollen grains of 58 and 62 taxa were identified in the two parts, respectively. The pollen spectrum reflected the floristic diversity of the region. The main pollen producers at the sites were characterized by some allergenic pollen and were identified as Cupressaceae/Taxaceae, Urticaceae, Pistacia sp., Quercus sp., Platanus sp., Fraxinus sp., and Xanthium sp. These pollen types contributed to the total pollen sum with a percentage of more than 80% at both monitoring sites. The highest amount of pollen grains was recorded in April. The greatest number of species was recorded in May, when 42 types (AS) and 44 types (EP) were present.     

Evaluation of trace element contents of some herbal plants and spices retailed in Kayseri,Turkey

The trace element contents of seven kinds of herbal plants and spice samples retailed in local markets in Kayseri-Turkey were determined by flame atomic absorption spectrometry after digestion with HNO₃/H₂O₂ mixture. The concentration ranges for the studied elements were found as 6.0–15.2, 0–32.2, 80.0–324.8, 8.1–386.3, and 13.1–36.2 μg/g for copper, nickel, iron, manganese, and zinc, respectively. The levels of cobalt, lead, and chromium ions in all the investigated samples were found to be below the detection limit of flame atomic absorption spectrometry. The results found in the present work were compared with values in the literature.     

PCDD/F contamination on surface soil in the vicinity of a hazardous waste incinerator: is it possible a different trend?

This study is the first to investigate the contamination of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) on surface soils in the vicinity of the first hazardous waste incinerator of Turkey. In the study, 24 soil samples were taken from a 1625-m-radius circle whose center is the stack of the incinerator. This process was repeated 1 year later. Since the acquired average PCDD/F concentrations of the two sampling campaigns (0.05 and 0.02 ng WHO-toxic equivalent (TEQ)/kg) were meaningfully low compared to the related literatures, a new sampling campaign was carried out to control this inconsistency, but this time in a foreign laboratory (0.56 ng WHO-TEQ/kg). In the same period, eight gas samples were taken from the stack under different operational conditions of the facility. According to the evaluations of the findings, the geographical-meteorological data of the study area and the specific operational conditions of the facility corroborate the concentrations of the first and the second soil samplings rather than the third one. The major underlying reason for the inconsistency of the soil concentrations may be the fact that the data analysis procedures used by the laboratories are different. The author suggests a hypothesis which argues that the soils in the vicinity of a hazardous waste incinerator may have significantly lower concentration levels than in related literatures.     

Heavy metal contents of refined and unrefined table salts from Turkey, Egypt and Greece

Trace metal contents of 28 of refined and unrefined table salt samples from Turkey, Egypt and Greece have been determined by flame atomic absorption spectrometry after coprecipitation by dysprosium(III) hydroxide. Copper, nickel, cobalt, manganese, lead and cadmium levels were found in the range of 0.17-0.47, 0.16-1.57, 0.22-0.48, 0.26-4.68, 0.50-1.64 and 0.14-0.30 microg g(-1), respectively. The results found in the presented work were compared with literature values.     

Trace element content in marine algae species from the Black Sea, Turkey

Trace element content of marine algae species collected from the Black Sea coasts were determined by atomic absorption spectroscopy after microwave digestion. Trace element content in marine algae species were 1.70-17.1 microg/g for copper, 3.64-64.8 microg/g for zinc, 9.98-285 microg/g for manganese, 99-3,949 microg/g for iron, 0.50-11.6 microg/g for chromium, 0.27-36.2 microg/g for nickel, 11-694 microg/kg for selenium, 0.50-44.6 microg/kg for cadmium, 1.54-3,969 microg/kg for lead, 1.56-81.9 microg/kg for cobalt. While iron was the highest trace element concentration, cadmium was the lowest in samples. Most of the analyzed samples were edible. The samples are consumed for human diet in several countries.     

Spatial variability of depth and salinity of groundwater under irrigated ustifluvents in the Middle Black Sea Region of Turkey

Information on the potential risk for soil salinity buildup can be very helpful for soil salinity management in irrigated areas. We evaluated the spatial and temporal variability of groundwater salinity (GWS) and groundwater depth (GWD), which are two of the most important indicators of soil salinity, by indicator kriging technique in a large irrigated area in northern Turkey. GWS and GWD were measured on a monthly basis from irrigation season (August 2003) to rainy season (April 2004) at 60 observation wells in the 8,187-ha irrigated area. Five indicator thresholds were used for GWS and GWD. The semivariogram for each of the thresholds for both variables was analyzed then used together with experimental data to interpolate and map the corresponding conditional cumulative distribution functions (CCDF). Risk for soil salinity buildup was greater in the irrigation season compared to that in the rainy season. The greatest risk for soil salinity buildup occurred in the eastern part of the study area, suffering from poor drainage problem due to malfunctioning drainage infrastructure, as indicated by the CCDF of GWS and GWD obtained in both seasons. It was concluded that a combination of mechanical and cultural measures should be taken in high-risk locations to avoid further salinity problems.