Burcu Onat

Personal exposure of commuters in public transport to PM2.5 and fine particle counts

Abstract To investigate fine particulate air pollution generated by public transport and its microenvironment, PM 2.5 measurements and particle number counts for six particle size ranges (0.3–0.5 µm, >0.5–1.0 µm, >1.0–3.0 µm, >3.0– 5.0 µm, >5.0–10 µm and >10 µm) were obtained for four public transport modes: bus, metro–bus, car and walking. The measurements were repeated for each transport mode twice a day for 7–10 measurement days. The highest average PM 2.5 concentration was measured inside a bus (10 6 µg/m 3 ) during rush hours. The highest single peak measurement was a concentration of 316 µg/m 3 for walking during non–rush hours. The PM 2.5 level in a car with the air conditioning fan off was approximately 2.5 times lower than the level with the air conditioning fan on. Moderate correlations were found between PM 2.5 concentrations and wind speed. Weak correlations were found between PM 2.5 concentrations, relative humidity and temperature. The results showed that the diameters of most of the particles were smaller than 0.5 µm, regardless of the transport mode. The average fine particle number (size range 0.3–0.5) for all transport modes ranged from 54 647 to 209 746 particles/10 3 cm 3 during rush hours and from 49 423 to 184 866 particles/10 3 cm 3 during non–rush hours.

Assessment of particulate matter in the urban atmosphere: size distribution, metal composition and source characterization using principal component analysis

In this study, the size distribution of airborne particles and related heavy metals Co, Cd, Sn, Cu, Ni, Cr, Pb and V in two urban areas in Istanbul: Yenibosna and Goztepe, were examined. The different inhalable particles were collected by using a cascade impactor in eight size fractions (<0.4 μm, 0.4-0.7 μm, 1.1-2.1 μm, 2.1-3.3 μm, 3.3-4.7 μm, 4.7-5.8 μm, 5.8-9 μm and >9 μm) for six months at each station. Samples were collected on glass fiber filters and filters were extracted and analyzed using ICP-MS. Log-normal distributions showed that the particles collected at the Yenibosna site have a smaller size compared to the Goztepe samples and the size distribution of PM was represented the best by the tri-modal. The average total particle concentrations and standard deviations were obtained as 67.7 ± 17.0 μg m(-3) and 82.1 ± 21.2 μg m(-3), at the Yenibosna and Göztepe sites, respectively. The higher metal rate in fine and medium coarse PM showed that the anthropogenic sources were the most significant pollutant source. Principal component analysis identified five components for PM namely traffic, road dust, coal and fuel oil combustion, and industrial.

Assessment of Fine Particulate Matters in the Subway System of Istanbul

The purpose of this study was to determine the concentrations of fine particulate matter (PM2.5) at six subway stations. The PM2.5 levels were compared at the platforms, inside the trains’ cabin and at the train driver’s cabin in the first section of the train. The measurements were grouped into three sections: (1) six underground platforms, (2) trains’ cabin and (3) train driver’s cabin in the Aksaray-Airport light metro line (M1) and the Taksim-4.Levent metro line (M2). On average, the highest PM2.5 concentrations were recorded in the underground platforms. The average daytime PM2.5 concentrations varied from 49.3 to 181.7 µg·m−3 at the two subway line platforms. The PM2.5 levels measured at five stations were higher than the ambient air PM2.5 standard declared by US-EPA, given as 35 µg·m−3 for a 24-h arithmetic mean. The second highest PM2.5 concentration was recorded inside the trains (61 to 73 µg·m−3), followed by train driver’s cabin (50 to 74 µg·m−3) of the M1 and M2 lines. When the train was in the subway tunnels, the PM2.5 concentrations increased. The correlation (R2) between the PM2.5 level on the platform and the depth of the underground stations was 0.88 (p<0.01). The highest PM2.5 levels were recorded in the morning and evenings.

Fine Iron Aerosols Are Internally Mixed with Nitrate in the Urban European Atmosphere

Atmospheric iron aerosol is a bioavailable essential nutrient playing a role in oceanic productivity. Using aerosol time-of-flight mass spectrometry (ATOFMS), the particle size (0.3-1.5 μm), chemical composition and mixing state of Fe-containing particles collected at two European urban sites (London and Barcelona) were characterized. Out of the six particle types accounting for the entire Fe-aerosol population, that arising from long-range transport (LRT) of fine Fe-containing particles (Fe-LRT, 54-82% across the two sites) was predominant. This particle type was found to be internally mixed with nitrate and not with sulfate, and likely mostly associated with urban traffic activities. This is in profound contrast with previous studies carried out in Asia, where the majority of iron-containing particles are mixed with sulfate and are of coal combustion origin. Other minor fine iron aerosol sources included mineral dust (8-11%), traffic brake wear material (1-17%), shipping/oil (1-6%), biomass combustion (4-13%) and vegetative debris (1-3%). Overall, relative to anthropogenic Asian Fe-sulfate dust, anthropogenic European dust internally mixed with additional key nutrients such as nitrate is likely to play a different role in ocean global biogeochemical cycles.

Sustainable technologies for recycling and reuse: an overview

Recycling and reuse of water, air and soil pollutants, and wastes has been an emerging issue during the recent decade to protect natural resources and the environment (Corder et al. 2015; Colling et al. 2016). A number of national and international environmental programs and projects have been increasingly performed. The most recent outcomes of those projects/research have been published referring to mostly favor sustainable technologies for recycling and reuse of various resources that include energy recovery from organic fraction of municipal solid wastes (Cesaro et al. 2016), from food wastes (Karmee 2016), from wastewater treatment plant sludge (Batstone et al. 2015; ColmenarSantos et al. 2016), compost recovery from organic fraction of municipal solid waste (Cesaro et al. 2015), and fertilizers from wastewater (Hukari et al. 2016; Puchongkawarin et al. 2015; Shepherd et al. 2016). Various industrial wastes have been recycled to produce new products or reuse in the process purposes such as vehicle recycling processes (Li et al. 2016), recycling schemes for waste dry batteries (Lin and Chiu 2015), of waste aggregate in cement bound mixtures for road pavement bases and sub-base (Pasetto and Baldo 2016), of waste automotive laminated glass and valorization of polyvinyl butyral (Swain et al. 2015), of blast furnace sludge (Drobíková et al. 2016), and recycling of electronic wastes (Awasthi et al. 2016). Besides advanced treatment technologies among which membranes are the common ones, have been applied for recycling and reuse of urban (Bunani et al. 2013) and industrial wastewaters (Zheng et al. 2015). Additionally, valorization of renewable energy sources has been a pioneering recycling and reuse sector (Byrnes et al. 2016; Sahoo 2016) that is somewhat discussed for not being green (Keramitsoglou et al. 2016) and causing environmental impact (Sokka et al. 2016). This special issue is composed of a number of scientific works presented at the 2 International Conference on Recycling and Reuse, held on 4–6 June 2014 in Istanbul, Turkey. The biennial Conference was jointly organized by Bogazici University, Environmental Sciences Institute and Istanbul University, Environmental Engineering Department, Turkey. The purpose of the Conference was to provide an advanced platform for researchers and practitioners to exchange emerging ideas and to investigate key issues on whole and progressive aspects of recycling and reuse. The Conference program included a wide spectrum of important topics in recycling and reuse concerns of wastewaters and wastes, advanced wastewater treatment, and membrane technologies for recycling and reuse. A total number of 90 oral and 155 poster presentations were given in the topics of advanced oxidation technologies, waste reduction, water and wastewater management, solid waste treatment and management, hazardous waste management, resource use, renewable energy technologies, current and future recycling markets, public health issues, and legislations and policies of recycling and reuse. This special issue, specifically named BSustainable Technologies for Recycling and Reuse^ includes 4 papers that were selected among 25 invited papers submitted to an essential peer-review process. Three of the accepted papers present examples for removal of emerging pollutants using different advanced treatment options before reuse, and the other gives a case study on mercury containing substances flow in Turkey that would be a good example for policy decision support in developing countries as well. The guest editors expect that this issue should provide an overview of recent works done in BRecycling and Reuse^ fields and fulfills scientific gaps to provide an important contribution to scientific and technological communities. Responsible editor: Philippe Garrigues

Climate Change and Greenhouse Gases in Turkey

Within the course of significant changes in the history of humankind, the Industrial Revolution, together with the developments in science and technology, resulted in increases in the world population, which led to increases in anthropogenic greenhouse gas emissions and concerns for human welfare. As a result, the composition of the atmosphere has changed, creating a change in the global climate. According to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, this change will severely diminish the impact of the struggles for sustainable development. Turkey is located in the Mediterranean Basin, which will be the region affected most from climate change, the first impact of which will be severe drought. Climate change will significantly influence water, agriculture, and energy sectors. Because of steady population growth and intensive industrialization, total greenhouse gas (GHG) emissions in Turkey steadily increased from 1990 through 2015. The energy sector in Turkey accounted for 67.8% of total GHG emissions, followed by industrial processes at 15.7%, agriculture at 10.8%, and waste at 5.7%. According to the modeling results covering between 2016 and 2099 in Turkey, especially in summer, an increase in the mean temperature between 1 and 4 °C is expected throughout different areas of the country.

Black Carbon Aerosols in Urban Air: Sources, Concentrations, and Climate Change

Black carbon (BC) is one of the key atmospheric aerosol components of locomotive air quality and climate change. BC has the capacity to absorb light across all visible wavelengths; it reradiates solar radiation as heat, inducing a climate warming effect. Due to its shorter lifetime in the atmosphere compared to carbon dioxide, it is an excellent target for emission reductions. BC is a specific marker of primary combustion of fossil fuel and biomass. BC concentrations in urban areas are variable; in developed countries, motorized transport vehicles are considered to be the most important source of BC, whereas in developing countries, biomass burning may be important. The interest of policy makers in BC was rise up owing to arising evidence on health effects and the impact of BC on global warming. The authors present here a general knowledge on BC to clarify its sources, concentration levels, effect on climate change, and adverse health effect.

The relationship between particle and culturable airborne bacteria concentrations in public transportation

This study aims to determine the in-vehicle and outdoor culturable airborne bacteria concentration, fine particle (PM2.5) concentration and particle number concentration for six size ranges (0.3–0.5 µm, >0.5–1.0 µm, >1.0–3.0 µm, >3.0–5.0 µm, >5.0–10 µm, and >10 µm) and to assess the relation between the culturable airborne bacteria and PM2.5 concentrations in different public transport vehicles. The measurement campaign was conducted in the morning and evening onboard of the Metrobus, red-bus and outdoors. PM2.5 concentrations in the Metrobus and red-bus were observed as 58.8 ± 10.2 µg/m3 and 76.2 ± 30.9 µg/m3, respectively, and the outdoor value was about two times more. For both types of public transportation, the amount of internal environment particulate matter and the amount of external environment particulate matter displayed a high level of correlation (red-bus/outdoors, R = 0.97; Metrobus/outdoors, R = 0.88) with the particulate matter size. The concentration of Staphylococcus aureus correlated with PM2.5 concentrations in the Metrobus and Staphylococcus spp. was found to be higher in in-vehicle. The number of commuters, vehicle ventilation type and outdoor air entering the vehicles probably caused the differences in in-vehicle culturable airborne bacteria and particle concentrations.

The 2nd International Conference on Recycling and Reuse, held on June 4–6, 2014, in Istanbul, Turkey

This special issue of the Desalination and Water Treatment Journal is dedicated to the 2nd International Conference on Recycling and Reuse, held on 4–6 June 2014 in Istanbul, Turkey. This international conference was jointly organized by Boğaziçi University, Environmental Sciences Institute and Istanbul University, Environmental Engineering Department, Turkey. The purpose of the conference was to provide an excellent platform for researchers and practitioners to exchange emerging ideas and investigate key issues such as:

Determination the relation between the target regulations about End of Life Vehicles (ELVs) and greenhouse gas emissions in Turkey

The aim of this study was to determine the potential reduction on GHG emission from transportation sector, in particular from passenger cars (according to car figures in 2016). The GHG reductions were determined for different scenarios (1) current situation (2) to implement of the taxation system based on carbon emission (3) to make reduction on taxes (rate of 18% and 27%) and (4) to apply a regulation for End of Life Vehicles (ELVs) We found that the best scenario is to apply the regulation for ELVs. If the regulation is applied for banning vehicles which were produced before 2000, 1996 and 1990, the reduction rate of CO2 emission would be 48%, 36% and 26%, accordingly. The CO2 reduction rates in transportation sector calculated for different scenarios will change approximately 2% to 15%. Consequently, the total GHG emission reduction in Turkey will be about 0.2% to 2%.