Assessment of house dust trace elements and human exposure in Ankara, Turkey.

One of the impacts of the COVID-19 pandemic is leading people remain at homes longer than ever. Considering the elongation of the time people spend indoors, the potential health risks caused by contaminants including heavy metals in indoor environments have become even more critical. The purpose of this study was to evaluate the levels and sources of heavy metals in indoor dust, to assess the exposure to heavy metals via indoor dust, and to estimate the associated health risk. The highest median value was measured for Zn (263 µg g-1), while the lowest median concentration value was observed for Cd (0.348 µg g-1). The levels of elements measured in the current study were found to be within the ranges reported in the other parts of the world, mostly close to the lower end of the range. House characteristics such as proximity to the main street, presence of pets, number of occupants, and age of the building were the house characteristics influencing the observed higher concentrations of certain heavy metals in houses. Enrichment factor values range between 1.79 (Cr) and 20.4 (Zn) with an average EF value of 8.80 ± 6.80 representing that the targeted elements are enriched (EF>2) in indoor dust in Ankara. Positive matrix factorization results showed that the heavy metals in the house dust in the study area are mainly contributed from sources namely outdoor dust, carpets/furniture, solders, wall paint/coal combustion, and cigarette smoke. Carcinogenic and non-carcinogenic risk values from heavy metals did not exceed the safe limits recommended by EPA. The highest carcinogenic risk level was caused by Cr. The risk through ingestion was higher than inhalation, and the risk levels were higher for children than for adults.

Incorporation of solar-heated aeration and greenhouse in grass composting.

Composting is an environment-friendly method for recycling organic waste, and incorporation of heat and aeration can enhance favorable conditions for microbial growth in the process. This research aimed to evaluate the influence of the introduction of solar heat and aeration to the waste grass exposed to the composting process. The compost piles studied were subjected to different processes: application of solar-heated aeration, only-aeration, solar heating with a greenhouse, and control. Solar-heated air was introduced to a compost pile of grass clippings and compared with a greenhouse compost system. The composting process of 70 days was monitored for temperature, oxygen, moisture, organic matter loss, and humification rate. Germination index has been used to evaluate the maturation of the composts produced. The highest temperature was obtained at the compost pile with the greenhouse. This system reached the highest temperature (68.2 °C) on day 15; the ambient temperature on that day was 20.6 °C. The decreases in the C/N ratios after day 70 of composting were 20% and 15% for the greenhouse and the system where solar-heated air was introduced, respectively. Although the temperature of the solar-heated air was higher than that of the greenhouse, thermophilic temperature levels could not be reached in the aerated compost pile, which indicated a cooling effect of excessive aeration even with the heated air. Composting of grass clippings resulted in a decrease in organic matter content and enhancement in seed germination and root growth, obtaining high GI levels, inferring no phytotoxicity. This study showed that composting of grass clippings with low C/N ratios and high humidity can still be possible by using solar energy.

Characterization of sewage sludge incineration ashes from multi-cyclones and baghouse dust filters as possible cement substitutes.

Incineration is not a final disposal method for sludge management since a significant amount of ash is generated. Although some published literature reported on the use of sewage sludge ashes (SSAs) as a cement replacement, none of them referred to the air pollution control unit of the incinerator where the SSA is collected. The properties of SSAs from different air pollution control units were investigated with the purpose of usage as a cement replacement in the present study. The SSA samples obtained from multi-cyclone units (MC-SSA), where SSA is collected at the bottom of the unit with the help of inertia and centrifugal forces, and baghouse dust filters (BHD-SSA), where SSA is collected at the fabrics of the unit, of the sludge incinerator were analyzed for chemical and physical characteristics, including heavy metal leaching, mineralogy (XRD), and particle morphology (scanning electron microscopy). Mortar samples were prepared with 15 and 30% of MC-SSA and BHD-SSA additions and analyzed for workability, strength activity, strength development, and freeze-thaw resistance. Heavy metal leaching results of both of the MC-SSA and BHD-SSA and their mortars were below the legal requirements of landfills, inferring that the toxic elements in SSA would not be of environmental concern in case SSA is used in cement matrices. The present study identified the variability of the physical and chemical properties of both SSAs over time and their differences. Incompliances of the SSAs to the pozzolanic material standards were observed, although moderate pozzolanic activity was concluded. In order to obtain the required flow value, different amounts of polycarboxylate ether-based superplasticizer were used in all of the mixtures. The levels of amorphous phases were found to be 23.3 and 39.3% for MC-SSA and BHD-SSA, respectively. MC-SSA exhibited less porosity with larger agglomerates than BHD-SSA. Ninety-day compressive strength levels of MC-SSA mortars with 15% replacement, which was found as 50.53 MPa, was higher than that of BHD-SSA mortars by 6% (47.65 MPa). The freeze-thaw resistance and water adsorption capacity of SSA mortars were comparable with that of the cement mortars. It was inferred that the contribution of SSA substitution to the strength development was influenced by hydraulic activity more than pozzolanic activity.Graphical abstract.

Ultrasound and heterogeneous photocatalysis for the treatment of vinasse from pisco production.

Production of the distilled alcohol pisco results in vinasse, dark brown wastewater with high polyphenols contents and chemical oxygen demand (COD). No prior research exists on the efficiency of advanced oxidations processes (AOPs) in treating pisco vinasse. Therefore, the purpose of this study was to assess the efficiency of ultraviolet (UV), ultrasound (US), US + UV, heterogeneous photocatalysis (HP), and HP + US treatments. Polyphenols, COD, and color removal, as well as oxidation-reduction potential, were monitored over a 60-minute treatment period. Energy consumption levels and synergies were also calculated. The HP + US treatment achieved the best removal ratios for polyphenols (68%), COD (70%), and color (48%). While the HP treatment was the second most efficient in terms of polyphenols (62%), COD (58%), and color (40%) removal, this AOP comparatively required the least amount of energy. Considering the energy efficiency and relatively high pollutant-removal rates of the HP treatment, this AOP is recommended as a practical alternative for treating pisco vinasse.

Food loss and waste management in Turkey.

Food waste can be an environmental and economic problem if not managed properly but it can meet various demands of a country if it is considered as a resource. The purpose of this report is to review the existing state of the field in Turkey and identify the potential of food waste as a resource. Food loss and waste (FLW) was examined throughout the food supply chain (FSC) and quantified using the FAO model. Edible FLW was estimated to be approximately 26milliontons/year. The amount of biodegradable waste was estimated based on waste statistics and research conducted on household food waste in Turkey. The total amount of biodegradable waste was found to be approximately 20milliontons/year, where more than 8.6milliontons/year of this waste is FLW from distribution and consumption in the FSC. Options for the end-of-life management of biodegradable wastes are also discussed in this review article.

A review on paint sludge from automotive industries: Generation, characteristics and management.

The automotive manufacturing process results in the consumption of several natural sources and the generation of various types of wastes. The primary source of hazardous wastes at an automotive manufacturing plant is the painting process, and the major waste fraction is paint sludge, which is classified with EU waste code of 080113* implying hazardous characteristics. The amount of the paint sludge generated increases every year with the worldwide increase in the car production. The characteristics of the paint sludge, which mainly designate the management route, are mainly determined by the type of the paint used, application technique employed, and the chemicals applied such as flocculants, detackifiers, pH boosters, antifoam agents, and biocides as well as the dewatering techniques preferred. Major routes for the disposal of the paint sludges are incineration as hazardous waste or combustion at cement kilns. Because of high dissolved organic carbon content of the paint, the paint sludge cannot be accepted by landfills according to European Union Legislations. More investigations are needed in the field of paint sludge recycling such as recycling it as a new paint or as other formulations, or making use of the sludge for the production of construction materials. Research on the applicability of the paint sludge in composting and biogasification can also be useful. Ongoing research is currently being conducted on new application techniques to increase the effectiveness of paint transfer, which helps to prevent the generation of paint sludge. Advancements in paint and coating chemistry such as the reduction in the coating layers with its thickness also help to decrease the level of paint sludge generation. Investigations on the effects of the chemicals on the recycling potential of paint sludges and consideration of these effects by the chemical manufacturer companies would be extremely important. This review presents the formation of paint sludge, the factors affecting its characteristics, common disposal routes, the findings of the field trips to automotive manufacturing plants in Turkey, and a summary of the characterization findings of the paint sludge samples from a plant in Turkey.

Immobilization of antimony waste slag by applying geopolymerization and stabilization/solidification technologies.

During the processing of antimony ore by pyrometallurgical methods, a considerable amount of slag is formed. This antimony waste slag is listed by the European Union as absolutely hazardous waste with a European Waste Catalogue code of 10 08 08. Since the levels of antimony and arsenic in the leachate of the antimony waste slag are generally higher than the landfilling limits, it is necessary to treat the slag before landfilling. In this study, stabilization/solidification and geopolymerization technologies were both applied in order to limit the leaching potential of antimony and arsenic. Different combinations ofpastes by using Portland cement, fly ash, clay, gypsum, and blast furnace slag were prepared as stabilization/solidification or geopoljymer matrixes. Sodium silicate-sodium hydroxide solution and sodium hydroxide solution at 8 M were used as activators for geopolymer samples. Efficiencies of the combinations were evaluated in terms of leaching and unconfined compressive strength. None of the geopolymer samples prepared with the activators yielded arsenic and antimony leaching below the regulatory limit at the same time, although they yielded high unconfined compressive strength levels. On the other hand, the stabilization/solidification samples prepared by using water showed low leaching results meeting the landfilling criteria. Use of gypsum as an additive was found to be successful in immobilizing the arsenic and antimony.

Air-soil exchange of PCBs: levels and temporal variations at two sites in Turkey.

Seasonal distribution of polychlorinated biphenyls (PCBs) at the air-soil intersection was determined for two regions: one with urban characteristics where traffic is dense (BUTAL) and the other representing the coastal zone (Mudanya). Fifty-one air and soil samples were simultaneously collected. Total PCB (Σ82 PCB) levels in the soil samples collected during a 1-year period ranged between 105 and 7,060 pg/g dry matter (dm) (BUTAL) and 110 and 2,320 pg/g dm (Mudanya). Total PCB levels in the gaseous phase were measured to be between 100 and 910 pg/m(3) (BUTAL) and 75 and 1,025 pg/m(3) (Mudanya). Variations in the concentrations were observed depending on the season. Though the PCB concentrations measured in the atmospheres of both regions in the summer months were high, they were found to be lower in winter. However, while soil PCB levels were measured to be high at BUTAL during summer months, they were found to be high during winter months in Mudanya. The direction and amount of the PCB movement were determined by calculating the gaseous phase change fluxes at air-soil intersection. While a general PCB movement from soil to air was found for BUTAL, the PCB movement from air to soil was calculated for the Mudanya region in most of the sampling events. During the warmer seasons PCB movement towards the atmosphere was observed due to evaporation from the soil. With decreases in the temperature, both decreases in the number of PCB congeners occurring in the air and a change in the direction of some congeners were observed, possibly caused by deposition from the atmosphere to the soil. 3-CB and 4-CB congeners were found to be dominant in the atmosphere, and 4-, 5-, and 6-CBs were found to dominate in the surface soils.

Seasonal variations of polychlorinated biphenyls in surface soils and air-soil exchange in Bursa, Turkey.

This study investigates the seasonality of polychlorinated biphenyl (PCB) levels in soils of Bursa city located in northwestern Turkey. Forty-three soil samples were collected each season during a 1-year period. Air and soil samples were collected concurrently 3 or 3 times in a month during a 1-year monitoring period from 2 of the 43 locations. The samples were analyzed for 83 PCB congeners. Flux levels, fugacity fraction (ff) levels, and net flux levels of PCB congeners were calculated for 2 specific regions. The influence of humic substance and total organic carbon content of soil on PCB levels was also examined. The mean concentrations of the total PCBs were 1275 ± 1120, 4075 ± 2740, 2185 ± 2010, and 1150 ± 1540 pg/g dry weight in spring, summer, autumn, and winter seasons, respectively. Four- and 5- CBs were the most abundant homologue groups in soils, and their contribution to the total was 55 %. PCB-74, followed by PCB-153, was the dominant congener. Air and soil PCB levels increased together with the soil temperature suggesting the influence of instantaneous air-soil exchange toward the equilibrium conditions. Flux and ff levels also showed a positive significant correlation with soil temperature. Flux levels were mostly positive for the 2 regions indicating volatilization from soil to air.

Air-soil exchange of PCBs: seasonal variations in levels and fluxes with influence of equilibrium conditions.

The variations in the occurrences of PCB congeners both in soil and air were investigated in conjunction with each other, and the changes in the fugacity fractions and flux levels were examined on a seasonal basis. Air and soil samples were collected concurrently two or three times in a month during a one-year monitoring at two different locations in Bursa, located in the northwestern Turkey. Fugacity fractions and net flux levels of PCB congeners were calculated. Air and soil PCB levels increased together as the soil temperature increased, suggesting the influence of instantaneous air-soil exchange towards the equilibrium conditions. The flux levels and fugacity fractions also showed a positive significant correlation with soil temperature. Flux levels were positive for the dates with fugacity fractions above 0.5, indicating volatilization from soil to air.

Spatial and temporal distribution of polychlorinated biphenyl (PCB) concentrations in soils of an industrialized city in Turkey.

Surface soil (0-5 cm) samples from 43 sampling sites covering the entire urban territory of Bursa, an industrialized city in Turkey, were collected in each season and analyzed for 83 polychlorinated biphenyls (PCBs). The mean concentration of total PCBs (Σ83 PCBs) among all sites over the four seasons was 2121.51 pg/g dry weight (dw), with a range of 207.61-5461.95 pg/g dw. Total PCB concentrations in the soil samples collected near an industrial region were the highest in all seasons. In general, PCB patterns were dominated by low-chlorinated homologue groups (≤ 5 Cl groups at a 79% level). The predominant homologue group found in Bursa city soils was the penta-CBs (29.1%) followed by the tetra-CBs (25.5%) and tri-CBs (17.6%). A total of seven dioxin-like PCB congeners (CB-77, 81, 105, 114, 118, 123, and 126) were found in every sampling location and their mean total concentration for all locations and seasons was 259.27 pg/g dw, with a range of 7.02-1581.13 pg/g dw. A significant relationship (r = 0.77, p < 0.01) was found between the concentrations of dioxin-like PCBs and the seasonal average sum of PCB concentrations. A correlation between light congeners (

Comparison of polycyclic aromatic hydrocarbons levels in sludges from municipal and industrial wastewater treatment plants.

This study was carried out to investigate the concentrations and potential sources of the polycyclic aromatic hydrocarbons (PAHs) in sludge of 14 wastewater treatment plants (WWTPs). Sludge samples were collected from 2 municipal WWTPs, 11 industrial WWTPs, and 1 sanitary landfill leachate treatment plant within the city of Bursa, Turkey during the summer of 2008. Ultrasonication was applied for extraction and gas chromatography-mass spectrometry was used to analyze the PAH contents of the samples. Twelve of the 16 EPA-listed PAH compounds were determined. Total PAH concentrations (Sigma(12) PAHs) determined in all of the sludge samples ranged from 1,781 to 19,866 microg/kg dry matter (dm). The sum of 8 of the 11 EU PAHs varied between 1,481 and 17,314 microg/kg dm, and 3 of the samples exceeded the proposed EU limit for land application. One of the automotive industry sludges contained the highest level of PAHs, followed by one of the municipal sludges. The average sum of 5- and 6-ring PAH compounds in all of the sludge samples amounted to almost 65% of the total PAHs. The diagnostic ratios of specific PAHs were calculated to determine the dominant sources for the PAHs in the sludge samples.

Industrial hazardous waste management in Turkey: current state of the field and primary challenges.

A holistic evaluation of a country's hazardous waste management (HWM) practices is useful in identifying the necessary actions to focus on. Based on an analysis of industrial hazardous waste (HW) generation in Turkey, this paper attempts to critically evaluate and report current Turkish HWM practices and discuss the primary challenges to be addressed. The generation of industrial HW for Turkey reported in 2004 was 1.195 million tons, which accounted for 7% of the total industrial solid waste (ISW) generated by the manufacturing industry, and for nearly 4.9% of the total solid waste generated in the country. The HW generated by the top five manufacturing product categories--basic metals, chemicals and chemical products, food and beverages, coke and refined petroleum, motor vehicles and trailers--accounted for 89.0% of total industrial HW. 21% of the HW generated in 2004 was recycled or reused, and 6% was sold or donated, whereas 73% was sent to ultimate disposal. 67% of the HW sent to ultimate disposal was disposed of at municipal landfills. The total capacity of the existing regional HW facilities is 212,500 tons/year, which accounts for about 24% of the HW to be disposed. Turkey has identified the HW problem in the country and enacted legislation, designated a lead agency, and promulgated rules and regulations. Several new initiatives are planned for improving HW management nationally; however, some HWM problems will be persistent due to previous and existing industrial development plans. These development policies led to the concentration of industry in regions marked by precious agricultural fields and high population density. This occurred because the government previously exhibited a default prioritization towards industrial development, leading to insufficient implementation of regulations on HW generators. Some of the problems may also be rooted in other countries that allow illegal trans boundary HW movements despite international regulations.

Prediction of the PCB pollution in the soils of Bursa, an industrial city in Turkey.

The purpose of this study was to predict the equilibrium soil concentrations and distributions of Sigma(41)Polychlorinated Biphenyl (PCB) congeners from the air data measured at 4 sites (urban, suburban, residential, and industrial) in Bursa between 2004 and 2005. The soil-air partition coefficient (K(SA)) was used for the predictions. Predicted soil concentrations ranged from 25 pg/g to 690 pg/g, while the atmospheric concentrations fluctuated between 35 pg/m(3) and 1112 pg/m(3). The soil concentrations were found to be in agreement with the lower range of European and global values, and below the regulatory limits. The urban and residential sites yielded higher PCB concentrations and a higher degree of heavier congeners than the sites characterized as suburban. The urban and residential sites were dominated by hexa-chlorinated biphenyls (CBs), followed by tri-CBs, while the industrial site was dominated by tri-CBs, followed by tetra-CBs. PCB congeners of 153, 180, 138, 118, and 101 were higher in all locations. The effect of the temperature changes on the concentrations was found to be insignificant, as the correlations ranged between 0.0009 and 0.22 for all sites. The K(SA) approach yielded reasonable results, and it is recommended to use this approach when there is limited data about the pollution levels of a certain media such as soil by using the measured levels of the other media such as air.

Steel foundry electric arc furnace dust management: stabilization by using lime and Portland cement.

The purpose of this study was to determine an appropriate treatment for steel foundry electric arc furnace dust (EAFD) prior to permanent disposal. Lime and Portland cement (PC)-based stabilization was applied to treat the EAFD that contains lead and zinc above the landfilling limits, and is listed by USEPA as hazardous waste designation K061 and by EU as 10 02 07. Three types of paste samples were prepared with EAFD content varying between 0 and 90%. The first type contained the EAFD and Portland cement, the second contained the EAFD, Portland cement, and lime, and the third contained the EAFD and lime. All the samples were subjected to toxicity characteristics leaching procedure (TCLP) after an air-curing period of 28 days. pH changes were monitored and acid neutralization capacity of the samples were examined. Treatment effectiveness was evaluated in terms of reducing the heavy metal leachability to the levels below the USEPA landfilling criteria. An optimum composition for the EAFD stabilization was formulated as 30% EAFD +35% lime +35% Portland cement to achieve the landfilling criteria. The pH interval, where the solubility of the heavy metals in the EAFD was minimized, was found to be between 8.2 and 9.4.

Properties of steel foundry electric arc furnace dust solidified/stabilized with Portland cement.

Electric arc furnace dust from steel production is generated in considerable amounts worldwide and needs to be treated as hazardous waste. The aim of this study was to investigate the properties of electric arc furnace dust solidified/stabilized by using Portland cement. Mortar and paste samples were prepared with varying waste-to-binder ratios between 0% and 90%. A comprehensive experimental program was designed including XRF characterization, setting time, unconfined compressive strength, and toxicity characteristics leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), and acid neutralization capacity (ANC) tests. The results were evaluated in order to determine if the solidified /stabilized product can be disposed of at a landfill site with domestic waste or at a segregated landfill. The effect of using sand on S/S performance was also investigated. The results indicated that the solidification /stabilization process using PC helps the heavy metals to be bound in the cement matrix, but the TCLP leaching results exceeded the EPA landfilling limits. The SPLP leaching results conformed to the limits implying that the waste or S/S products can be disposed of at a segregated landfill; however the low ANC of the S/S products reveals that there may be leaching in the long-term. The sand used in the mortar samples adversely affected the S/S performance, causing higher heavy metal leaching levels, and lower pH levels in the leachate after the TCLP extraction than those measured in the leachate of the paste samples.

Stabilization and solidification of waste phosphate sludge using portland cement and fly ash as cement substitute.

Stabilization and solidification of the waste phosphate sludge (WPS) using Portland cement (PC) and fly ash (FA) were studied in the present work. The WPS content in the cement mortars varied from 5% to 15%. Setting times were measured, and unconfined compressive strengths (UCS) were determined for the mortars cured in water for 3, 7, 28, 56, and 90 days. Zinc and nickel leaching of the solidified products were measured according to the Toxicity Characteristic Leaching Procedure. Setting times were extended as the WPS content in the paste samples increased. The UCS values of the mortar containing 5% WPS solidified by using 95% PC were similar to the reference sample. Use of 10% FA as cement substitute increased the UCS values by 10% at the end of curing period of 56 days. The WPS contained initially 130.2 mg L(-1) of zinc and 22.7 mg L(-1) of nickel. The zinc and nickel leached from the 5% WPS solidified by using 95% PC were measured as 3.8 mg L(-1) and 0.4 mg L(-1), respectively. These metal concentrations were below the limits given by the U.S. Environmental Protection Agency for landfilling the solidified wastes.

Ecological risk assessment and problem formulation for Lake Uluabat, a Ramsar State in Turkey.

Unlike the United States and the European Union, developing countries do not have sufficiently structured legal and institutional systems to apply certain environmental management tools such as ecological risk assessment. However, it is important for countries with valuable environmental and ecological resources to have appropriate tools and to strengthen their environmental management capabilities and capacities for the sake of those resources. The case study described in this paper attempts to be a case study towards developing environmental management plans, especially in developing countries. The problem formulation step of Ecological Risk Assessment applied in this study contributed to the basic elements of an environmental management plan including the following: the partnership-building process, prioritization of the problems and issues of the ecosystem, and development of the action plan. Based on the information provided by participants from a series of workshops held to develop an environmental management plan for Uluabat Lake, ecosystem risks were ranked and an action plan was formed. The results obtained with the aid of fuzzy set theory provided a base for identification of the action steps by allowing scientific information to be included in the process. The degree to which Uluabat Lake's problem formulation fits into the existing legal framework of Turkey is also analyzed in this paper.