This study investigates the concentrations, pollution levels, and human health implications of heavy metals in road dust collected along the Marmaray rail line and the adjacent coastal road on the Asian side of Istanbul, Turkiye. The average concentrations of the analyzed trace elements followed the order: Si > Fe > Al > Ti > Mn > Zn > Ba > Cr > Sr > Pb > Ni > V > Sn > Co > Sc > Sb > Ag > As. In three indices (I-geo, EF, and ERF), Zn showed the highest levels among the elements analyzed. Spatial distribution patterns were visualized using GIS tools, while Correlation Coefficient Analysis and Principal Component Analysis were applied to identify pollution sources, demonstrating that railway operations, fossil fuel combustion, traffic emissions, and mixed crustal/ship-derived inputs were the primary contributors. Human health risk assessments for adults and children were performed across ingestion, inhalation, and dermal exposure pathways. The results indicated that Cr poses a substantial public health risk, contributing significantly to both carcinogenic and non-carcinogenic effects among regular commuters as well as residents around the sampling area. Carcinogenic risk was found to be high for adults (8.2E-07) than children (5.0E-07). The cumulative hazard index for children exceeded the acceptable threshold, indicating non-cancer risks of concern. These outcomes underscore the extensive influence of anthropogenic activities on urban environmental quality and public health. Given the presence of heavy metal emissions from traffic, expanding large-scale public transportation services to reduce this emission burden significantly contributes to mitigating potential environmental and health impacts. Continuous environmental and health assessments are therefore essential for effective impact evaluation and public health management.

Landfill gas (LFG) is primarily composed of CH4 and CO2, together with a wide range of trace compounds generated during the decomposition of domestic waste in landfills. During energy production from LFG, trace compounds such as sulfur-containing compounds and siloxanes cause the formation of metal oxide-based deposits. However, studies integrating gas composition with deposit chemistry, phase identification, and multi-technique validation on the same samples remain limited. This study aims to establish the linkage between LFG composition and deposit formation, focusing on the transformation of organometallic compounds into oxide phases. A multi-analytical approach including scanning electron microscopy with energy-dispersive spectroscopy, X-ray diffraction, inductively coupled plasma optical emission spectroscopy, wavelength-dispersive and energy- dispersive X-ray fluorescence was applied to characterize deposits collected from engine components. In addition to the organometallic compounds identified in standard LFG analyses at the study site, other compounds reported in the literature and detected through gas analysis were also considered. The results demonstrate that Si and S are directly associated with LFG constituents, while Ca is linked to lubricant oil additives, and metal(loid)s (Sb, Sn, As) are related to organometallic compounds present in LFG. A broad spectrum of trace elements was identified, providing comprehensive elemental coverage and highlighting potential occupational health risks associated with elements such as As, Cr, Ni, Ba, Zn, and Zr. By integrating gas composition, and deposit chemistry, this study provides new insights into deposit formation and supports the development of improved gas quality control strategies and mitigation approaches for both engine performance and health protection.

Dust from intensive mining operations like quarrying is a major concern in urban areas and should be assessed from environmental and public health perspectives. This study investigates the geochemical properties of trace elements in street dust and their associated health risks, based on samples collected from 40 georeferenced sites across three densely populated districts of Istanbul (Sultangazi, Eyüp, and Gaziosmanpaşa) located near and affected by quarries. The concentration distribution of 21 elements (Si > Al > Fe > Mg > Na > Ti > Mn > Zn > Ba > Cu > Cr > V > Pb > Ni > Sb > Co > As > Cd > Hg > Mo > Sn) was determined using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), indicating that elements associated with natural sources are more dominant. The concentrations of potentially toxic elements exhibited wide spatial variability, with Co ranging from 6.14 to 4467.49 mg kg−1, Cr from 36.78 to 2933.88 mg kg−1, Zn from 47.75 to 3828.63 mg kg−1, Pb from 6.89 to 1166.41 mg kg−1, and As from 0.25 to 1032.63 mg kg−1. Pollution levels were assessed, revealing extremely high contamination levels for Co based on the enrichment factor (EF = 107.99) and for Sn based on the geo-accumulation index (Igeo = 8.73). Human health risk assessment identifies ingestion as the dominant exposure pathway, with non-carcinogenic risk exceeding acceptable thresholds for children, particularly for Co, Cr, and As which their total hazard index was 2.65E+01. Carcinogenic risk via inhalation remains within acceptable limits. The findings emphasize the dominant role of particulate matter from quarries in contributing to urban street dust pollution. Moreover, the high levels of elements classified as potentially toxic elements (PTEs) in road dust, combined with quarrying activities, can lead to the accumulation of heavy metals in environmental components, disrupting ecosystem balance and posing significant environmental and human health risks to communities living in these areas.

The use of scanning electron microscopy/energy-dispersive X-ray spectrometry (SEM-EDS) is an effective technique in analyzing the elemental contents of atmospheric particles and revealing their morphological structures. This study is to classify and quantify the elemental composition of PM10 by analyzing size-segregated collected particles using SEM-EDS in Istanbul region. This study compared the changes in trace elements in size segregated PM10 between the day of the Saharan dust event (SDE) day and the following dust-free day by determining them using SEMEDS. In SEM images, the differences in the morphological structures of aerosol particles from different sources adhering to the glass filter fibers were clearly seen. The effective directions of particle transport were determined using HYSPLIT air mass backward trajectories for the airflows for both days. After the SDE, the 7.76-fold decrease in PM10 concentration effectively demonstrates the effect on the transportation of desert dust to distant regions. Al, As, Ba, Ca, Cd, Cl, Cr, K, Mg, Na, Pb, S, Sb, Si, Ti, V and Zr were detected in the atmospheric particles by SEM-EDS. The SDE caused an increase in PM10 concentration in the region as well as effected on the elemental composition of different size of the particles especially Ca, Mg and Ti. In contrast, Cl, Cr, S and V were the dominant elements in the dust-free day samples, each originating from urban sources. This study provides the qualitative measurement of the elements collected on the filter by SEMEDS analysis in a short time with less experimental application.

Atmospheric particulate matter (PM) is considered to pose a significant risk to human health due to its ability to remain in the respiratory tract. However, little is known about the organic composition of these PM. The organic portion of airborne PM consists of a highly complex mixture of compounds that represent major sources of air pollution. This study aims to develop a sensitive method for separating this complex organic mixture into eight individual fractions, arranged in increasing polarity from non-polar to polar. This approach will improve our understanding of the chemical composition of airborne fine particulate matter, allowing for the identification and quantification of a greater number of organic compounds. An advanced silica-gel long-column chromatographic method was used to separate the organic compounds in the sample extract. Initially, the chromatographic method was tested on a synthetic multi-component test organic standard mixture (OSM), which contains groups of organic compounds, such as n-alkanes, alkanoic acids, benzothiazole, steroids, hydroxy/methoxy phenols, resin acids, polycyclic aromatic hydrocarbons (PAHs), polycarboxylic acids, secondary biogenics, and oxygenated-PAHs, comprising a total of 53 individual compounds. Compound recovery was typically high for the OSM. Next, extracts obtained from PM2.5 samples collected from Pittsburgh’s ambient air were tested using silica gel column chromatography. The fractionation scheme produced well-defined separations of different organic compound classes for both the OSM and actual ambient sample extracts. In a case study, the fractionation process demonstrated its power by successfully separating overlapped sandaracopimaric acid and an unknown organic compound. The chemical fractionation method appears to generate highly selective markers for ambient air samples.

Non-purified landfill gas (LFG) leads to the formation of complex deposits in combustion chambers due to impurities such as siloxanes, sulfur compounds, and organometallic compounds containing elements such as Si, S, Sb, Sn. This study focused on identifying the elemental composition of deposits from four combustion chambers using analytical techniques including SEM-EDS, WDXRF, and microwave digestion ICP OES. The dominant element, Si, with concentrations (wt%) in the deposits was measured by SEM-EDS, ICP-OES, and WDXRF, respectively, as follows: 17.04 +/- 8.59, 21.89 +/- 4.39, and 16.63 +/- 0.94 for cylinder head deposits, and 13.28 +/- 6.97, 15.40 +/- 5.40, and 12.64 +/- 1.64 for piston head deposits. Excluding C, O and N, which could not be analyzed by all three techniques, the multi-analytical approaches demonstrated strong correlations between EDS results and those obtained from WDXRF and ICP OES, with R-2 values of 0.9173 and 0.9002 for cylinder head deposits, respectively. It was also revealed that the elemental composition of deposits varied between combustion chambers. The average mass fractions of all deposit surfaces were ranked as follows for elements exceeding 1 %: O (45.38 %) > Si (16.67 %) > Ca (9.87 %) > Sb (7.21 %) > S (5.98 %) > Sn (3.51 %) > C (2.83 %) > P (2.35 %). Elements below 1 % were ranked as: Na (0.91 %) > N (0.80 %) > Al (0.74 %) > Fe (0.48 %) > Mg (0.30 %). Consequently, the multi-spectrometry analysis approach provides a more comprehensive understanding of the deposit composition, enabling the determination of primary contributors and the most elements. Future studies may involve more general determining the concentrations of organometallic compounds in the LFG, which are the source of the elements found in the deposit.

Florida has the most land used to grow sugarcane crops in the United States. The preharvest sugarcane leaf burning elevates ambient particle matter (PM) concentrations in rural areas with dominant sugarcane agriculture (Belle Glade) and affects the air quality of coastal urban sites (Delray Beach). In this study, ambient particles segregated by size were analyzed to identify trace organic compounds from PM sources that may cause adverse health effects. The sampling campaign was conducted simultaneously at urban and rural sites, and revealed that the organic compound concentration of each particle size varies significantly between the sugarcane burning season (SBS) in January and sugarcane growing season (SGS) in May. The results indicated that PM3 contains at least 76% of the organic compound concentrations detected in the samples collected from both sites and during both seasons. The concentrations of trace organic compounds were higher in the SBS than in the SGS. Combustion-oriented hopanes, polycyclic aromatic hydrocarbons (PAHs), and oxygenated PAHs were mainly detected in PM0.49. The detection of elevated levoglucosan concentrations at the urban site indicates that fine particles generated from biomass burning traveled from the rural site to the urban site. Secondary organic compounds such as dicarboxylic acids, phytol, and 6,10,14-trimethyl-2-pentadecanone exhibited similar concentration patterns in the rural and urban sites during both seasons. In the SGS, PM10 concentrations at both sites were extremely similar; however, the organic compound levels were lower at the rural site than at the urban site in the SBS. This result should be investigated further by researchers investigating the health aspects of organic compound concentrations.

Combustion chamber deposits adversely affect the operating performance of gas engines. In this study, the elemental composition of deposit samples collected from the inner surface of combustion chambers in gas engines across three different facilities was examined using various methods. The proportional changes in metal oxides along the internal cross-sectional surfaces of the deposits were examined to depict the deposit formation process from beginning to end. Additionally, the study investigated the identification of metals accumulated in the engine oil, their contribution to deposit formation, and the accumulation mechanisms of metal oxide nanoparticles on the engine’s interior metal surfaces. The main elements identified in the deposits from the Odayeri and Kömürcüoda facilities were Si, S, and Ca, whereas deposits from the Dilovası facility contained Si and Sb. These major elements, identified by SEM-EDS, were confirmed through XRF analysis. XRD analysis further confirmed the presence of Ca and S as CaSO4 crystals in the deposits. Ca originates from additives used to increase the total base number of engine oil and control the corrosive effects of landfill gas. It has been determined that silicon accumulates in engine oil over time. An important finding is that metal oxides in the combustion chamber primarily accumulate through impaction, sticking, and thermophoresis mechanisms.

The combustion chamber deposit (CCD) is a major problem for the gas engines that formed accumulating of the metal oxides during the oxidation of trace compounds in the landfill gas (LFG). Therefore, the LFG was purified with activated carbon (AC) before in use to reduce deposit formation in gas engines. The AC treatment demonstrated the high removal capacity by reducing to below 1 % of the mass ratios of Si and Ca in the deposit. Unfortunately, the AC treatment caused the formation of black deposit in the intercooler that was analyzed by EDS and XRD. First time in this study, the variation of the elements of the CCD was comparatively investigated over a long period of time in 2010 and in 2019 without -AC treatment of LFG. The variation of the concentrations of C, Ca, N, S, Sb, Si- and Sn in the CCD were confirmed by the analysis with ICP-OES and SEM-EDS for 9-year period. It was determined with EDS analysis that while Sb and Sn were relatively low, C and N were high based on 2010. It has been determined that there is a proportional change depending on the time of the elements forming in the deposit.

Vehicles emit greenhouse gas (GHG) and air pollutants during the collection of municipal solid waste. In this study, GHG emissions and global warming factors (GWFs) from waste collection vehicles were calculated for four different fuel types (diesel, gasoline, compressed natural gas and electricity) in Kocaeli, Turkey. Results showed that GHG emissions were determined by using a model and manual calculations as 10,853 tons CO2-eq and 10,265 tons CO2-eq, respectively. If diesel is used, the GWF values for the model and manual calculations were determined as 18 kg CO2-eq ton−1 and 17 kg CO2-eq ton−1, respectively. Furthermore, when gasoline, CNG, and electricity were used, GWFs were calculated as 13.3 kg CO2-eq ton−1, 9.2 kg CO2-eq ton−1 and 2.6 kg CO2-eq ton−1, respectively. This study demonstrated that alternative fuels, especially electricity, have a great potential to reduce GHG emissions. In addition, opening up new transfer stations or a new landfill site can be considered as important steps in reducing GHG emissions.

The aim of this study is to investigate the deposit formed on the inner surface of the combustion chamber of the landfill gas engine based on its morphological structure and elemental composition. The responsible elements for deposit formation that affects the engine's operating performance were determined on the differences of the microstructural and chemical composition of deposits using Scanning Electron Microscope with Energy Dispersive Spectrometry and Focused Ion Beam. The Oxygen element of metal oxides made up about half of the deposit mass. Nitrogen was also detected in the deposit by FIB analysis. The amount of elements on the bottom surface to the engine part were ordered Si > S > Ca > Al > Mg > Sn > Sb, on the other side, the elements on the top surface of the accumulated deposit were Ca > S > Si > Sn. The elemental distribution of the top surface was overlapped with both results of the elemental distribution of the longitudinal lateral section area and the cross-sectional area. The amount of Si increased from the top surface to the bottom surface, and the amount of Ca and S decreased. These findings revealed that Si, S, and Ca have various roles in deposit formation from start to end. WDXRF Spectrometer analysis confirmed that Si, S, and Ca are the major elements with approximately half of the deposit is made up of oxygen element. The detected Sb and Sn made the deposits to be considered as hazardous material in the disposal process.

Şehirlerde insan kaynaklı faaliyetler sonucu atmosfere önemli miktarda sera gazı emisyonu salınmaktadır. Bu gazların salınımlarının hızla artması sonucu küresel ısınma ile beraber, iklim değişikliğine neden olduğu bilinmektedir. Bu çalışmada, Kocaeli ilinde başlıca şehir kaynaklarından salınan metan (CH4), karbondioksit (CO2) ve nitröz oksit (N2O) gazlarının salınım değerleri Hükümetler Arası İklim Değişikliği Paneli’nin (IPCC) Kademe 1 yöntemi ile CO2 eşdeğerine çevrilerek hesaplandı. Yoğun nüfusu ve sanayi faaliyetlerine sahip olan Kocaeli’de, elektrik üretimi ve tüketimi, ısınma, ulaşım ve atık yönetiminden kaynaklanan sera gazı emisyonlarının toplam miktarları 2015, 2016 ve 2017 yılları için sırasıyla 28 131 515 ton CO2-eşd, 25 985 586 ton CO2-eşd ve 21 228 854 ton CO2-eşd olarak hesaplandı. Kocaeli ilinde üç yılın sera gazı emisyonu ortalamasına göre % 50.8'lik payı ısınmadan kaynaklandığı belirlendi. Konutlarda ısınma ihtiyacını karşılamak için yıllara bağlı olarak doğal gaz kullanımı artarken, kömür kullanımının azalmasıyla sera gazı emisyonunda azalma sağlandı. Ayrıca, araç yakıtı kullanımında motorin ve benzinden kaynaklı sera gazı emisyonu oranları sırasıyla %93.5 ve %6.5 değerleri 2017 için bulundu. Motorin, ulaşımdan kaynaklı dikkate alınabilir seviyede sera gazı emisyonu kaynağı olarak belirlendi. Atık yönetiminden kaynaklanan sera gazı ise, toplam emisyonun %0.8 değerinde olup çok düşük bir orana sahiptir. Ayrıca, toplu ulaşımda sera gazı emisyonunu azalmak için CNG yakıtlı otobüslerin kullanımı artırıldı. Genel olarak bakıldığında Kocaeli ilinde 2015 yılından 2017 yılına kadar sera gazı emisyon trendinde %24.5’lik bir düşüş gerçekleşti. Bu durumda, sektörler bazında en fazladan en aza sera gazı emisyonu kaynakları sırasıyla şunlardır; ısınma, elektrik tüketimi, elektrik üretimi, ulaşım, atık yönetimi.

Air pollution affected quality of life and public health due to high concentration levels of air pollutants in Istanbul, especially in 1990s. Major air pollution sources in Istanbul caused elevation of the air pollutants in ambient air of the megacity. To protect human health, the levels of PM10 and SO2 were reduced by taking effective actions such as the reduction of utilization of coal, fuel oil, wood combustion for residential heating, expending natural gas network and improving the quality of diesel and gasoline. Intelligent Traffic Systems (ITS) were applied to reduce the air pollutant emission from transportation by reducing travelling time. Overall, this study evaluates air pollution sources in Istanbul based on previous source apportionment studies that guide the emission reduction strategies. The improvement on PM10 and SO2 demonstrated as 50% and 98% reduction respectively since 1990s to 2014.

Combustion chamber deposits cause numerous undesirable negative effects on gas engine performance. The purpose of this study was to understand the morphological structure of deposit surface and to determine the major and minor elements of the chemical composition of the deposits formed on the surface of the combustion chamber of the reciprocating gas engine utilizing landfill gas (LFG). The morphological structure of deposits was analyzed by scanning electron microscopy (SEM) that revealed that the bottom surface displayed more smooth and noticeable cracks and in contrast to the top surface, demonstrated more irregular and wavy surface with adhesion of different size and shaped nanoparticles. On the other hand, the following crystals; CaSO4, Fe3+O(OH), FeSO4 and CaSO4·2H2O were determined in the deposits by X-ray powder diffraction (XRD) for the first time. Besides, the Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES) and X-Ray Fluorescence (XRF) analysis confirmed that the mass ratios of Si, S, Ca, Sn were high above 2% in both analyses that measured 25 elements in all samples. The energy dispersive spectroscopy (EDS) spectrums represented the dominant peaks of Si, S, Ca, Sn as well. The results revealed that Si, S, Ca and Sn emerged as the main elements of the deposits in the application of three elemental analysis methods.

The largest sugarcane-growing area in the United States is in South Florida. An estimated 7 million tons of dry sugarcane leafy biomass is removed from the fields before harvest by burning the leaves off the sugarcane stalks. Preharvest sugarcane leaf foliage burning is a major source of airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), biogenic trace elements such as K, volatile hydrocarbons and other pollutants. In one harvesting period, approximately 22 million tons of CO2, a greenhouse gas, is released, 7 million tons from leaf foliage preharvest burning alone and 15 million tons from burning sugarcane bagasse in the sugar mills for power generation. In this study, PM10 was collected from Belle Glade, close to the sugarcane-growing area, and from Delray Beach, an urbanized area along the East Coast of Florida. The PM samples were analyzed for trace elements and close to organic compounds. To elucidate the importance of preharvest sugarcane biomass smoke emissions on air quality, 39 trace elements, 18 PAHs, and levoglucosan were selected to apportion ambient PM constituents. Al, Ca and to a great extend also Mg are the major soil-related trace elements and key markers for fugitive soil dust emissions. Similarly, sea salt aerosol blown from the Atlantic Ocean into Florida added appreciably to PM10 trace elements concentration, especially Na and Cl. Approximately half of the sea salt aerosol (PM10-portion) by mass is removed from the atmosphere during the transport of ocean air from Delray Beach to Belle Glade. Ambient acid displacement reactions caused a substantial portion of the Cl ((3) over tilde0%) to be liberated from the sea salt aerosol to the atmosphere during transport as gaseous HCl. The PAH concentrations at Belle Glade were high when the biomass combustion markers levoglucosan and K also showed the highest concentrations. This indicates that during the sugarcane harvest season, when leaf foliage is burned off just before harvest, most of the ambient PAHs associated with PM10 are indeed related to preharvest burning, harvesting machinery emissions, bagasse burning in sugarcane mills, and other related activities that consume biomass and/or fossil fuels for sugarcane harvesting and processing. (C) 2019 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Kati atik depo sahalarinda olusan cop gazi enerji uretim icin gaz motorlarinda yakilarak genellikle elektrik enerji uretilmekte, ayni zamanda sera gazi emisyonu azaltilmaktadir. Cop gazi bunyesinde eser miktarda siloksanlar, H 2 S, merkaptanlar ve diger organik bilesikler bulunmaktadir. Enerji uretimi sirasinda cop gazinda bulunan bu bilesiklerin yuksek sicaklik ve basinc altinda oksitlenmesi sonucu olusan parcaciklar motorun yanma odasinin ekipmanlari yuzeyinde birikerek kompleks depozit olusturmaktadir. Bu calismada, Istanbul Komurcuoda Kati Atik Depolama Sahasindaki cop gazindan enerji uretimi tesisinde kullanilan gaz motorlarinin piston baslarinda biriken kompleks depozitlerin elementel icerikleri incelenmistir. Cop gazinin yanmasi sirasinda olusan metaloksitler yuksek sicaklik ve basincin etkisiyle motor parcalarina carparak tutunmakta ve motor yuzeyinde baslangicta ince bir tabaka olusturmaktadir. Yanma islemi suresince oksitlenmeye devam eden elementler bu tabaka uzerinde birikerek kalinligi yaklasik 0,5-2 mm arasinda degisen depozit formlarinin olusmasina neden olmaktadir. Bu depozitleri olusturan elementlerin kompozisyonunun belirlenmesi icin piston baslarindan alinan depozitler X-Isini Difraksiyonu (XRD) ve X-Isini Floresan (XRF) spektrometresi ile analiz edilmistir. Analizler neticesinde, XRD analizi sonucu kristal formda CaSO 4 ve XRF analizi sonucu 16 element tespit edilmistir. Alinan sonuclara gore, oksijen toplam kutlenin yaklasik olarak yarisini olusturmaktadir. kalsiyum, sulfur ve silisyum oranlari ise sirasiyla %16,6, %16,1 ve %14,6 olarak bulunmustur. Ayrica, depozitteki antimonun kutlece orani %3,5 olup, toksik bir element oldugu dikkate alindiginda bu oran diger elementlere nazaran yuksektir. Bu elementlerin tespiti cop gazi aritma sistemlerinde uygulanacak uzaklastirma metotlarinin secimine yon verecektir.