S. Levent Kuzu

Effect of diurnal changes in VOC source strengths on performances of receptor models

IntroductionThe effect of diurnal changes in strengths of volatile organic compound (VOC) sources on the performances of positive matrix factorization (PMF) and principal component analysis (PCA) was investigated using ambient measurement results that were taken during daytime and nighttime hours between March 24 and May 14, 2011, within Davutpasa Campus of Yildiz Technical University (Istanbul, Turkey).MethodsForty-five VOC species, ranging from C5 to C11 in volatility, were measured in the samples, 40 of which are included in the analyses. Ambient samples were grouped as daytime, nighttime, and all day datasets, and both PMF and PCA were applied to each dataset. A total of six source groups were extracted from each dataset: solvent use, general industrial paint use, gasoline and diesel vehicle exhausts, and biogenic as well as evaporative emissions. Estimated source contributions showed great diurnal variations.ResultsThe results suggested that extraction of possible sources by PCA depends greatly on the number of samples and the strength of the sources, while PMF produced stable results regardless of number of samples and source strengths.ConclusionAlthough PMF was unable to resolve gasoline vehicle and evaporative emissions, it was found to be successful in explaining diurnal fluctuations in source strengths, while the performance of PCA depends on the strength of emission source.

Estimation of atmospheric PCB releases from industrial facilities in Turkey

Abstract PCB production reduced or stopped in most countries in the late 1970s. According to the Stockholm Convention all the party countries have to list their PCB containing equipment and prepare national inventories. A national implementation plan was prepared in Turkey however, this plan is inadequate. Furthermore, there has not been any information prepared about stationary emission sources, contributing to atmospheric PCB inputs so far. It is aimed in this study to meet this deficit. This study will also help to make stronger comments on identifying sources of atmospheric PCB concentrations. PCB emission factors were utilized to determine the emissions. An average of 920 kg yr –1 of PCB emission is estimated in this study within the borders of Turkey. Highest contribution occurs in Kocaeli located on the North–West of the country by 47% of the overall emissions. Secondary most pollutant site is determined to be Aliaga on the west of the country. Both of this regions are heavily, industrialized and several different industrial processes are present. Iron–steel manufacturing and copper smelting processes comprises the 94% of the PCB releases from stationary sources. A simple box model was applied at two hot spots to determine potential contribution of the estimated emissions to atmospheric concentrations. In Dilovasi, the average contribution from industrial sources was determined as 244 pg m –3 while the average contribution for Aliaga was calculated as 126 pg m –3 within a 50 km x 50 km grid.

Compositional Variation of PCBs, PAHs, and OCPs at Gas Phase and Size Segregated Particle Phase during Dust Incursion from the Saharan Desert in the Northwestern Anatolian Peninsula

A dust incursion occurred in Istanbul on 1 February 2015 from the Saharan Desert. During this episode, 938 μg·m−3 of TSP concentration was observed. TSP concentration was 64 μg·m−3 and 78 μg·m−3 on the following two days. Particles of 3 μm were dominant during the episode; however, particles < 0.49 μm were dominant after the episode. The averages of total (gas

Investigation of temporal and spatial variations in atmospheric concentrations of PCDDs and PCDFs in Istanbul.

In this study, temporal and spatial variations of the atmospheric concentrations of polychlorinated-p-dibenzo dioxin (PCDDs) and polychlorinated dibenzofuran (PCDFs) congeners were investigated in Istanbul at three different locations. The highest average concentration (3481 fg/m(3)) was observed at the sampling location which is characterized by mixed source groups during colder months. The lowest average concentration (749 fg/m(3)) was observed at sampling station which is characterized by semi-urban characteristics. ∑PCDD/F concentration showed seasonal variation in this study. The highest average concentration was determined to be 4373 fg/m(3) in winter while the lowest average concentration was determined to be 498 fg/m(3) in summer.