Informal E -waste recycling in nine cities of Pakistan reveals significant impacts on local air and soil quality and associated health risks.

The global increase in electronic waste (e-waste) has led to a rise in informal recycling, emitting hazardous heavy metals (HMs) that threaten human health and ecosystems. This study presents the first comprehensive assessment of HM levels in dry deposition and soils at proximity of forty (40) informal e-waste recycling sites across Pakistan, between September 2020 to December 2021. Findings reveal that Zn (1410), Pb (410) and Mn (231) exhibited the higher mean deposition fluxes (µg/m2.day), derived from air samples, particularly in Karachi. Similarly, soils showed higher mean concentrations (µg/g dw) of Mn (477), Cu (514) and Pb (172) in Faisalabad, Lahore, and Karachi, respectively. HMs concentrations were found higher in winter or autumn and lower in summer. In addition, HM levels were significantly (p = 0.05) higher at recycling sites compared to background sites year-round, highlighting the e-waste recycling operations as the major source of their emissions. The Igeo index indicated moderate to extremely contaminated levels of Cu, Pb, Cd, and Ni in Karachi, Lahore and Gujranwala. Ingestion was found as a leading human exposure route, followed by dermal and inhalation exposure, with Pb posing the greatest health risk. The Cumulative Incremental Lifetime Cancer Risk (ILCR) model suggested moderate to low cancer risks for workers. Strategic interventions recommend mitigating health and environmental risks, prioritizing human health and ecosystem integrity in Pakistan's e-waste management.

Contamination of Soil by Obsolete Pesticide Stockpiles: A Case Study of Derince Province, Turkey.

The areal distributions of the soil organochlorine pesticide (OCP) levels were investigated at adjacent and surrounding sites of the obsolete pesticide stockpile warehouse in Kocaeli, Türkiye. OCP levels in soil at neighboring sampling locations (positioned at 0.4 to 3 km from the stockpile) varied from 0.4 to 9 µg/kg and 4.2 to 2226 µg/kg (dry weight) for ΣHCHs and ΣDDXs, respectively. Levels at adjacent locations (positioned within 20 m from the stockpile) were considerably higher, varying from 74 to 39,619 µg/kg and 1592 to 30,419 µg/kg for ΣHCHs and ΣDDXs, respectively. Levels of OCPs dropped abruptly with the horizontal distance from the stockpile and had different transect profiles. The enantiomer fractions (EFs) near the stockpile range from 0.494 to 0.521, 0.454 to 0.515, and 0.483 to 0.533 for α-HCH, o,p'-DDT, and o,p'-DDD, respectively. These near-racemic EFs suggested that observed soil OCP levels were mainly influenced by recent emissions from the stockpile. A comparison of OCP compositions observed in the soil at the present study with the technical HCHs and DDTs revealed that the material in the stockpile primarily contains byproducts that were discarded during DDT and Lindane production at the adjacent plant instead of their technical mixtures.

Gaseous elemental mercury emissions from informal E-Waste recycling facilities in Pakistan.

Detrimental effects of mercury (Hg) on ecosystems and human health have been well-documented. Whereas emissions of gaseous elemental mercury (GEM) from e-waste recycling have been reported in developed countries, much less is known about the situation in the Global South. Using a total of 132 passive air samplers, seasonally resolved concentrations of GEM in air were measured continuously at 32 informal e-waste recycling facilities and background location in Pakistan for a period of one year between September 2020 and December 2021. Annual average GEM concentrations at the studied locations ranged from 1.8 to 92 ng m-3. Among the studied cities, higher concentrations were measured in Karachi (mean ± s.d: 17 ± 22, range: 4.2-92 ng m-3), Lahore (16 ± 4.2, 8.2-22 ng m-3) and Peshawar (15 ± 17, 4.9-80 ng m-3), while lower levels were measured in Hyderabad (6.9 ± 6.2, 3.1-25 ng m-3), consistent with a higher rate of informal recycling activities in metropolitan areas. Seasonally, higher GEM levels occurred during autumn (15 ± 16: 3.3-92 ng m-3) and summer (13 ± 8.7: 1.8-80 ng m-3) than in winter (12 ± 8.4: 2.5-49 ng m-3) and spring (9.2 ± 7.3: 1.8-80 ng m-3), possibly reflecting enhanced volatilization at higher temperatures and/or varying magnitude of recycling operations in different seasons. Policies and strict regulations related to e-waste management should be developed and implemented urgently in the country.

Global intercomparison of polyurethane foam passive air samplers evaluating sources of variability in SVOC measurements.

Polyurethane foam passive air samplers (PUF-PAS) are the most common type of passive air sampler used for a range of semi-volatile organic compounds (SVOCs), including regulated persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), and emerging contaminants (e.g., novel flame retardants, phthalates, current-use pesticides). Data from PUF-PAS are key indicators of effectiveness of global regulatory actions on SVOCs, such as the Global Monitoring Plan of the Stockholm Convention on Persistent Organic Pollutants. While most PUF-PAS use similar double-dome metal shielding, there is no standardized dome size, shape, or deployment configuration, with many different PUF-PAS designs used in regional and global monitoring. Yet, no information is available on the comparability of data from studies using different PUF-PAS designs. We brought together 12 types of PUF-PAS used by different research groups around the world and deployed them in a multi-part intercomparison to evaluate the variability in reported concentrations introduced by different elements of PAS monitoring. PUF-PAS were deployed for 3 months in outdoor air in Kjeller, Norway in 2015-2016 in three phases to capture (1) the influence of sampler design on data comparability, (2) the influence of analytical variability when samplers are analyzed at different laboratories, and (3) the overall variability in global monitoring data introduced by differences in sampler configurations and analytical methods. Results indicate that while differences in sampler design (in particular, the spacing between the upper and lower sampler bowls) account for up to 50 % differences in masses collected by samplers, the variability introduced by analysis in different laboratories far exceeds this amount, resulting in differences spanning orders of magnitude for POPs and PAHs. The high level of variability due to analysis in different laboratories indicates that current SVOC air sampling data (i.e., not just for PUF-PAS but likely also for active air sampling) are not directly comparable between laboratories/monitoring programs. To support on-going efforts to mobilize more SVOC data to contribute to effectiveness evaluation, intercalibration exercises to account for uncertainties in air sampling, repeated at regular intervals, must be established to ensure analytical comparability and avoid biases in global-scale assessments of SVOCs in air caused by differences in laboratory performance.

Existence of SARS-CoV-2 RNA on ambient particulate matter samples: A nationwide study in Turkey.

Coronavirus disease 2019 (COVID-19) is caused by the SARS-CoV-2 virus and has been affecting the world since the end of 2019. The disease led to significant mortality and morbidity in Turkey, since the first case was reported on March 11th, 2020. Studies suggest a positive association between air pollution and SARS-CoV-2 infection. The aim of the present study was to investigate the role of ambient particulate matters (PM), as potential carriers for SARS-CoV-2. Ambient PM samples in various size ranges were collected from 13 sites including urban and urban-background locations and hospital gardens in 10 cities across Turkey between 13th of May and 14th of June 2020 to investigate the possible presence of SARS-CoV-2 RNA on ambient PM. A total of 203 daily samples (TSP, n = 80; PM2.5, n = 33; PM2.5-10, n = 23; PM10µm, n = 19; and 6 size segregated PM, n = 48) were collected using various samplers. The N1 gene and RdRP gene expressions were analyzed for the presence of SARS-CoV-2, as suggested by the Centers for Disease Control and Prevention (CDC). According to real time (RT)-PCR and three-dimensional (3D) digital (d) PCR analysis, dual RdRP and N1 gene positivity were detected in 20 (9.8%) samples. Ambient PM-bound SARS-CoV-2 was analyzed quantitatively and the air concentrations of the virus ranged from 0.1 copies/m3 to 23 copies/m3. The highest percentages of virus detection on PM samples were from hospital gardens in Tekirdag, Zonguldak, and Istanbul, especially in PM2.5 mode. Findings of this study have suggested that SARS-CoV-2 may be transported by ambient particles, especially at sites close to the infection hot-spots. However, whether this has an impact on the spread of the virus infection remains to be determined.

Development of a New Passive Sampling Method for the Measurement of Atmospheric Linear and Cyclic Volatile Methyl Siloxanes.

A new passive sampling method was developed and characterized to measure atmospheric volatile methyl siloxanes (VMS). The infrastructure of a commercial passive air sampler (PAS) was used along with XAD-2 resin as the adsorbent. Experimental sampling rates (SR) determined using collocated active and passive samplers ranged between 0.0363 (L5) and 0.0561 (D3) m3/day and agreed well with the theoretical ones. VMS uptake was highly linear for eight weeks. The precision of the method was very good (<10%). Compared to the other PASs used for VMS, the new method has several advantages (i.e., the sampler is much smaller, it has commercially available components, and the solvent requirement, equipment needed for extraction, and steps for sample preparation are minimal) while achieving similar or lower method detection limits. The developed method was applied to investigate the spatial distribution and possible sources of atmospheric VMS in the Izmir region. Field sampling covered 42 sites representing different source and land use areas. ΣVMS concentrations ranged between 41.4 and 981 ng/m3. The dominant VMS was D5 followed by D3 and D4. Spatial distributions indicated that the main VMS sources in the area were urban areas, wastewater treatment plants, and landfills where the VMS-containing products are used and disposed.

Measurement and Modeling the Phase Partitioning of Organophosphate Esters Using Their Temperature-Dependent Octanol-Air Partition Coefficients and Vapor Pressures.

Atmospheric concentrations of 11 organophosphate esters (OPEs) were measured in an urban area in Izmir, Turkey to explore their phase partitioning. Octanol-air partition coefficients (KOA) and vapor pressures (PL) of the OPEs were also measured as a function of temperature. Average Σ11OPE gas-phase concentrations were 1.77 ± 0.84 and 4.00 ± 1.77 ng/m3, while particle-phase concentrations were 1.95 ± 0.77 and 1.15 ± 0.36 ng/m3 during winter and summer, respectively. TCiPP1 dominated Σ11OPEs, followed by TnBP and TEP. OPE concentrations generally increased and shifted to gas-phase in the summer probably due to higher temperatures that favor partitioning to the gas-phase. Distribution between two phases covered a wide range from being primarily in gas-phase (TEP, TnBP) or particle-phase (EHDPP, TEHP, T2iPPP). Phase partitioning was also examined via four widely used models (KOA, Soot, Steady-State, and pp-LFER). All models underestimated the majority of particle-gas partition coefficients (KP) especially for the compounds having higher volatilities. Estimations based on the recently reported molecular weight of organic matter in urban aerosols (MWOM) and activity coefficients of OPEs in octanol (ξOCT) determined in the present study suggested that the basic assumptions of KOA-based models (i.e., ξOCT/ξOM and MWOCT/MWOM = 1) are not valid.

A Comprehensive Characterization of Particulate Matter, Trace Elements, and Gaseous Emissions of Piston-Engine Aircraft.

The gaseous and PM10 emissions of a piston-engine aircraft during ground operations at different engine states (six engine speed points and three air/fuel mixtures) representing certain flight phases were concurrently measured from the exhaust duct. PM10 emissions were sampled on a 47 mm-diameter polytetrafluoroethylene (PTFE) filter in order to be analyzed with an inductively coupled plasma mass spectrometry (ICP-MS/MS) to identify the presence and level of forty-eight elements. The most abundant element is found to be Pb (med = 4.6 × 106 ng m-3), which is 40 times the second most abundant element, Na (med = 1.1 × 105 ng m-3). The filters used for sampling exhaust gases tend to lighten with an increase in engine speed and leaning of the fuel mixture. The average of measured PM mass concentrations at all engine speeds were calculated to be 27.7 mg m-3 (full-rich) > 26.7 mg m-3 (best-power) > 24.7 mg m-3 (best-economy). The total mass of the trace elements constitutes an average of 24.1 ± 12.8% of the mass of PM. Electron microscope analyses suggest that the particles enriched by Al tend to agglomerate in a needle-shaped structure.

Source apportionment of biogenic and anthropogenic VOCs in Bolu plateau.

Total of 69 volatile organic compounds (VOCs) including both biogenic (isoprene, monoterpenes and oxygenated compounds) and anthropogenic ones were investigated in Bolu plateau by passive sampling technique. The main objective of this study was to determine spatial distributions, seasonal variations and possible sources for a wide variety of VOCs. Two-week passive sampling campaigns were performed in the winter and summer of 2017. Anthropogenic VOCs were predominant with a high percentage of contribution, 91% and 69% for winter and summer, respectively. Relatively higher concentrations of biogenic VOCs during the summer campaign were found to be related to higher solar intensity, temperature and amount of broad-leaved tree species. Benzaldehyde, toluene, phenol, benzene, hexane, decanal, benzothiazole, dodecane and acetophenone were anthropogenic VOCs with higher concentrations. Among biogenic VOCs, hexanal, alpha-pinene and limonene were found to be in higher concentrations. Spatial distribution maps were drawn for each VOC. Elevated concentrations of VOCs around the city center and major roads indicate that emissions from domestic heating activities and vehicular emissions can be significant sources of VOCs. The results were also supported by Positive Matrix Factorization (PMF) analyses and G-score distribution maps. Solvent evaporation, wood-coal combustion, biogenic emissions (pine, grain, grass), city atmosphere (styrene emissions from plastic production), biogenic (hornbeam, pine, juniper) and vehicle emissions were the identified as the primary VOC sources in Bolu plateau, contributing 31%, 22%, 8.0%, 8.0%, 13%, and 18%, respectively to the total VOC concentrations.

Organic chemical characterization of size segregated particulate matter samples collected from a thermal power plant area.

Kütahya city, a thermal power plant (TPPs) affected region of Turkey, has serious air quality problems like similar industrial regions of the world due to the emissions from three closely-located coal-fired TPPs, residential coal combustion along with the contribution of several industrial stacks. The organic chemical speciation of ambient size-segregated particulate matter (PM) was investigated during two seasons at two sites with different pollution characteristics (urban and rural). The ambient PM was collected using a high volume cascade impactor, with 6 stages: PM>10.2, PM10.2-4.2, PM4.2-2.1, PM2.1-1.3, PM1.3-0.69 and PM<0.69. Collected PM samples were extracted with organic solvents and the organic composition (Polycyclic aromatic hydrocarbons (PAHs), n-alkanes and carboxylic acids) was determined by GC-MS. Sources of the organic species were assessed using molecular PAH diagnostic ratios, carbon preference index and wax percentages. More than 70% of the PM-bound PAHs were quantified in submicron particles. Similarly, 34-42% of n-alkanes and approximately 30% of the carboxylic acids were found on the smallest particles. The main sources of the PM-bound organic species were considered as the anthropogenic emissions such as coal and biomass combustion and also vehicular emissions rather than the biogenic sources. Considerably high cancer risk levels were obtained through inhalation of PAHs. Seasonal variations and size distributions of the carboxylic acids and levoglucosan were also evaluated. Polar organic compound concentrations were higher in the summer period at both locations probably due to the higher sunlight intensity and temperature favoring their photochemical formation.

Intraday and interday variations of 69 volatile organic compounds (BVOCs and AVOCs) and their source profiles at a semi-urban site.

To study the intraday and interday patterns and possible sources of volatile organic compounds (VOCs), 6-h active sampling was performed in April, May, June, July, and August 2017 and in January 2018 in a semi-urban site in Bolu, Turkey. Totally 69 VOCs having biogenic (BVOCs, i.e., isoprene, monoterpenes and oxygenated VOCs) and anthropogenic origins (AVOCs) were examined. Fifty-four of sixty-nine analyzed VOCs could be detected. Decanal followed by benzaldehyde, benzene, phenol, and toluene were detected as the leading anthropogenic VOCs whereas alpha-pinene and hexanal were the dominant biogenic VOCs. There was a decrease in concentrations of most of the VOCs in January and April when light intensity and temperature were relatively low. Atmospheric levels of total biogenic VOCs exceeded that of anthropogenic VOCs in all months except for January and April. Dependence of biogenic VOC emissions on the light intensity, temperature and the increase in leaves were considered to be effective in their higher levels in summer and daytime periods. The daytime anthropogenic VOCs concentrations were higher than the nighttime anthropogenic VOCs probably due to intense vehicle traffic during working hours and/or increased volatilization from their sources at elevated temperatures. The VOCs that significantly and negatively correlated with ozone were evaluated as effective BVOCs in the ozone formation while the maximum incremental reactivity (MIR) method gave the contribution of AVOCs. Positive Matrix Factorization (PMF) was applied for the source apportionment. G score graphs and G score pollution roses were also used to identify possible sources of investigated VOCs. Solvent evaporation, gasoline-powered vehicle emissions, fossil fuel (residential heating), biogenic (hornbeam, grass, oak, beech) emissions, diesel/domestic activities and forested city atmosphere were identified as the possible VOC sources in the study area.

Elemental characterization of general aviation aircraft emissions using moss bags.

In light of growing concern and insufficient knowledge on the negative impact of aircraft emissions on environmental health, this study strives to investigate the air burden of major and trace elements caused by general aviation, piston-engine, and turboprop aircraft, within the vicinity of Eskisehir Hasan Polatkan Airport (Eskisehir, Turkey). The levels of 57 elements were investigated, based on moss bag biomonitoring using Sphagnum sp., along with chemical analyses of lubrication oil and aviation gasoline fuel used in the aircraft's operations. Five sampling sites were selected within the vicinity of the airport area to capture spatial changes in the concentration of airborne elements. The study demonstrates that moss bag biomonitoring is a useful tool in the identification of differences in the air burden by major and trace elements that have concentrated downwind of the aircraft emission sources. Moreover, pollutant enrichment in the Sphagnum moss bags and elemental characterization of oil/fuel are in agreement suggesting that Pb, followed by Cd, Cu, Mo, Cr, Ni, Fe, Si, Zn, Na, P, Ca, Mg, and Al are dominant elements that shaped the general aviation aircraft emissions.

Investigation of spatial and temporal variation of particulate matter in vitro genotoxicity and cytotoxicity in relation to the elemental composition.

Even though the outdoor air pollution and its major component Particulate Matter (PM) are recently classified as human carcinogen, attempts to elucidate the underlying mechanisms of PM toxicity are still crucial and continuing with in vitro approaches in various environmental circumstances. Present study investigated the genotoxicity (Comet assay) and the cytotoxicity (lactate dehydrogenase (LDH) leakage and the water-soluble tetrazolium (WST-1) assays) of 30 daily PM2.5 samples collected in the Kütahya province, to address their daily variability in effects with season (i.e. winter versus summer) and location (i.e. rural versus urban) using A549 human lung cancer epithelial cell line, as well as in relation to their chemical composition, specifically trace elements, organic carbon (OC) and elemental carbon (EC). The genotoxicity, measured by the percentage tail intensity (TI), of the daily PM2.5 samples at the traffic dense urban station was higher than that of the rural site for 80% of the parallel days. The genotoxicity was significant in the winter at the urban and in the summer at the rural site. Cytotoxicity was the highest for the winter urban samples. The PM2.5 mass, OC, and EC concentrations were not correlated to DNA damage, while there were correlations with Mn, Fe, Cu and Ba at the rural PM2.5 samples, and Mn, Co and Ni at the urban samples, respectively. The present study is confirming that the complex composition of PM2.5 originating from spatial and temporal changes can cause differences in the health effects.

Polybrominated diphenyl ethers (PBDEs) pollution in soil of a highly industrialized region (Dilovasi) in Turkey: concentrations, spatial and temporal variations and possible sources.

In this study, polybrominated diphenyl ethers (PBDEs) levels in soil were studied for a whole year in highly industrialized region of Turkey (Dilovasi) at 23 sampling sites. Σ8PBDE concentrations were between 0.15 and 286 µg kg-1 and the overall average concentration was 14.45 ± 25.07 µg kg-1 (average ± SD). BDE-209 was the most abundant compound. PBDEs concentrations decreased spatially as follows: industrial/urban > urban > suburban > rural. However, there was not any significant seasonal trend except for some industrial/urban sites. In the region, calm weather conditions prevailed during the sampling periods, enhancing the impact of the industrial emissions on nearby soil concentrations by atmospheric deposition without being diluted by winds. All congeners had significant but weak correlations with soil organic matter content indicating the impact of nearby sources rather than soil properties on soil PBDEs concentrations at the sampling sites. Positive matrix factorization method was also used for the apportionment of the PBDEs sources in Dilovasi soil. Industrial activities (i.e., iron-steel production, metallurgical processes, and recycling of plastics), traffic, and residential areas were found to be the primary sources of the measured PBDEs in the soil.

Spatio-temporal variations of atmospheric and soil polybrominated diphenyl ethers (PBDEs) in highly industrialized region of Dilovasi.

Polybrominated diphenyl ethers (PBDEs) were investigated in ambient air of a highly industrialized region at 23 different sampling sites for 12 months. Total concentrations of 8 PBDE congeners (Σ8PBDE) were found to be between 5.73 and 520 pg m-3 (94.7 ±â€¯78.9; average ±â€¯SD) and BDE-209 was the predominant congener, followed by BDE-47 and/or BDE-99. Their contributions to Σ8PBDE were 71 ±â€¯13, 9 ±â€¯4% and 8 ±â€¯4%; respectively. Compared to previous studies around the world, high concentrations detected in Dilovasi demonstrated the severity of atmospheric PBDE pollution in the area. For all sampling sites, average PBDE concentration obtained in summer (118.5 ±â€¯98.7 pg m-3) was higher than one found in winter period (79.7 ±â€¯59.1 pg m-3) and this seasonal difference was more obvious in industrial/urban sites (p < 0.05), probably due to enhanced volatilization from ongoing PBDE sources such as waste incineration and iron-steel plants. The soil-air exchange tendencies of PBDEs did not show substantial differences between the sampling periods with small variations for each congener. All congeners either tend to deposit to soil or to be within the equilibrium range for all seasons. This reflects the impact of local ongoing sources rather than temperature on the direction of soil-air exchange of PBDEs in this region. Specific congener ratios such as BDE-47/-99 and -99/-100 confirmed the impact of local sources rather than long-range transport on PBDE congeners in the study area. According to the Positive Matrix Factorization (PMF) results, the BDE-209 content of the first factor was found to be 91.7% and this factor was attributed to the deca-BDE technical formulations. The second factor was highly rich with both BDE-183 (%61) and BDE-28 (%52) and identified as octa-BDE technical products. The last factor was highly loaded with BDE-99, BDE-47, BDE-100, BDE-154 and BDE-153 and has been determined as the penta-BDE commercial formulations.

Determination of real-world emission factors of trace metals, EC, OC, BTEX, and semivolatile organic compounds (PAHs, PCBs and PCNs) in a rural tunnel in Bilecik, Turkey.

A field study was performed in a rural tunnel to determine pollutant concentrations, sources and on road vehicle emission factors (EFs) of particulate matter, trace metals, elemental carbon (EC), organic carbon (OC), benzene, toluene, ethyl benzene and xylenes (BTEX), and polycyclic aromatic hydrocarbons (PAHs). Emission factors (EFs) for polychlorinated naphthalenes (PCNs) and polychlorinated biphenyls (PCBs) were also determined. A 12-day extensive sampling campaign during morning and afternoon periods at inlet and exit stations of the tunnel was conducted. Morphology of the particles was also investigated by Scanning Electron Microcopy (SEM). Correlation analysis, factor analysis and diagnostic PAH ratios were utilized to identify emission sources of trace metals. Identified sources include brake wear (33%), resuspension of road dust (15%), tyre wear (12%), exhaust emissions (10%), and lubricants (9%). Based on the PAH diagnostic ratios, major sources of PAHs were estimated as diesel emissions. EFs were comparable with the literature and varied from 31.5 to 295.4 mg vehicle-1 km-1 with an average of 129.2 ±â€¯80 mg vehicle-1 km-1 for PM2.5. PM2.5-10 EFs varied between 15.9 and 236.1 mg vehicle-1 km-1 with an average of 96 ±â€¯30 mg vehicle-1 km-1. Average EC EFs were 40.3 ±â€¯9.8 mg vehicle-1 km-1 for PM2.5 samples and 19.5 ±â€¯0.5 mg vehicle-1 km-1 for PM2.5-10 samples while OC EFs were 33.7 ±â€¯18 and 15.5 ±â€¯8.4 mg vehicle-1 km-1 for fine and coarse particles, respectively. EFs of elements were generally 2 (Al) to 59 (Mg) times higher than those previously reported in the literature. Compared to literature, relatively higher EFs for Σ13PAHs (range: 48.1-168 µg vehicle-1 km-1, average: 84.3 ±â€¯46.4 µg vehicle-1 km-1) were obtained. BTEX emission factors were in the range of 4.2 ±â€¯4.7 mg vehicle-1 km-1 (m + p-xylene) and 16.7 ±â€¯10.5 mg vehicle-1 km-1 (toluene). Average EFs for ΣPCBs and ΣPCNs were 12.06 ±â€¯5.3 µg vehicle-1 km-1 and 88.9 ±â€¯70.4 ng vehicle-1 km-1, respectively.

Spatial variation of PAHs and PCBs in coastal air, seawater, and sediments in a heavily industrialized region.

Concurrent coastal seawater (n = 22), sediment (n = 22), and atmospheric samples (n = 10) were collected in the Aliaga industrial region, Turkey, to explore the spatial variation, sources, and air-seawater exchange of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Seawater Σ16PAH concentrations (particle + dissolved) ranged between 5107 and 294,624 pg L-1, while Σ41PCB concentrations were in the range of 880-50,829 pg L-1. Levels in sediments were highly variable ranging between 35.5-49,682 and 2.7-2450 µg kg-1 in dry weight for Σ16PAHs and Σ41PCBs, respectively. Atmospheric concentrations varied between 1791-274,974 and 104-20,083 pg m-3 for Σ16PAHs and Σ41PCBs, respectively. Sediment organic matter (OM) content and levels of Σ16PAHs and Σ41PCBs correlated weakly (r 2 = 0.19-0.23, p < 0.05) suggesting that the spatial variations of PAHs and PCBs were mainly affected by local sources rather than their sorption to OM. The geographical distribution of PAH and PCB concentrations in air, seawater, and sediment and factor analysis on the sediment levels pointed out that the major sources in the region are steel plants, petroleum refinery, petrochemical complex, ship breaking, loading/unloading activities at the ports, vehicular emissions, and fossil fuel combustion emissions. The direction of the air-seawater exchange was also explored by estimating seawater fugacity fractions of PAHs and PCBs. For PAHs, the number of cases implying deposition (43.0%) and volatilization (39.5%) was similar, while for PCBs, the number of cases implying volatilization (60.4%) was much higher compared to deposition (21.6%). Fugacity fractions were generally <0.36 (deposition) at the sites close to industrial and ship breaking activities where the highest seawater and sediment levels were measured, implying that atmospheric deposition is an important mechanism affecting seawater and sediment PAH and PCB levels.

Polychlorinated naphthalene (PCN) emissions from scrap processing steel plants with electric-arc furnaces.

Polychlorinated naphthalene (PCN) emissions of scrap iron processing steel plants were explored by measuring concentrations in stack gases of five plants, in the atmosphere (n=11) at a site close to those plants, and in soil at several sites in the region (n=40) in Aliaga, Izmir, Turkey. Observed stack-gas Σ32PCN levels from the plants without scrap preheating (189±157ngNm-3, average±SD, n=4) showed that they are substantial PCN emitting sources. Stack-gas Σ32PCN level for the plant with scrap preheating was considerably higher (1262ngNm-3). Similarly, Σ32PCN emission factor for this plant was substantially higher (11.9mgton-1) compared to those without scrap preheating (1.30±0.98mgton-1). Results have also suggested that the investigated steel plants emit large quantities of fugitive particle-phase PCNs. Measured soil Σ32PCN concentrations that are considered to be representative of the atmospheric levels were greatly variable in the region, ranging between 0.003 and 10.02µgkg-1 (dry wt). Their spatial distribution showed that main PCN sources in the region were the iron-steel plants. Ambient air levels (1620±800pgm-3) were substantially higher than ones observed around the world and in the study area verifying that the steel plants with electric arc furnaces (EAFs) are important PCN sources. Investigation of possible mechanisms suggested that the combustion processes also contribute to emissions from EAFs in addition to evaporation of PCNs present in the scrap iron.

Spatial and seasonal variations, sources, air-soil exchange, and carcinogenic risk assessment for PAHs and PCBs in air and soil of Kutahya, Turkey, the province of thermal power plants.

Atmospheric and concurrent soil samples were collected during winter and summer of 2014 at 41 sites in Kutahya, Turkey to investigate spatial and seasonal variations, sources, air-soil exchange, and associated carcinogenic risks of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The highest atmospheric and soil concentrations were observed near power plants and residential areas, and the wintertime concentrations were generally higher than ones measured in summer. Spatial distribution of measured ambient concentrations and results of the factor analysis showed that the major contributing PAH sources in Kutahya region were the coal combustion for power generation and residential heating (48.9%), and diesel and gasoline exhaust emissions (47.3%) while the major PCB sources were the coal (thermal power plants and residential heating) and wood combustion (residential heating) (45.4%), and evaporative emissions from previously used technical PCB mixtures (34.7%). Results of fugacity fraction calculations indicated that the soil and atmosphere were not in equilibrium for most of the PAHs (88.0% in winter, 87.4% in summer) and PCBs (76.8% in winter, 83.8% in summer). For PAHs, deposition to the soil was the dominant mechanism in winter while in summer volatilization was equally important. For PCBs, volatilization dominated in summer while deposition was higher in winter. Cancer risks associated with inhalation and accidental soil ingestion of soil were also estimated. Generally, the estimated carcinogenic risks were below the acceptable risk level of 10-6. The percentage of the population exceeding the acceptable risk level ranged from <1% to 16%, except, 32% of the inhalation risk levels due to PAH exposure in winter at urban/industrial sites were >10-6.

POPs in a major conurbation in Turkey: ambient air concentrations, seasonal variation, inhalation and dermal exposure, and associated carcinogenic risks.

Semi-volatile organic compounds were monitored over a whole year, by collection of gas and particle phases every sixth day at a suburban site in Izmir, Turkey. Annual mean concentrations of 32 polychlorinated biphenyls (∑32PCBs) and 14 polycyclic aromatic hydrocarbons (∑14PAHs) were 348 pg/m3 and 36 ng/m3, respectively, while it was 273 pg/m3 for endosulfan, the dominant compound among 23 organochlorine pesticides (OCPs). Monte Carlo simulation was applied to the USEPA exposure-risk models for the estimation of the population exposure and carcinogenic risk probability distributions for heating and non-heating periods. The estimated population risks associated with dermal contact and inhalation routes to ∑32PCBs, ∑14PAHs, and some of the targeted OCPs (α-hexachlorocyclohexane (α-HCH), ß-hexachlorocyclohexane (ß-HCH), heptachlor, heptachlor epoxide, α-chlordane (α-CHL), γ-chlordane (γ-CHL), and p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT)) were in the ranges of 1.86 × 10-16-7.29 × 10-9 and 1.38 × 10-10-4.07 × 10-6, respectively. The inhalation 95th percentile risks for ∑32PCBs, ∑14PAHs, and OCPs were about 6, 3, and 4-7 orders of magnitude higher than those of dermal route, respectively. The 95th percentile inhalation risk for ∑32PCBs and OCPs in the non-heating period were 1.8- and 1.2-4.6 folds higher than in the heating period, respectively. In contrast, the 95th percentile risk levels for ∑14PAHs in the heating period were 4.3 times greater than that of non-heating period for inhalation, respectively. While risk levels associated with exposure to PCBs and OCPs did not exceed the acceptable level of 1 × 10-6, it was exceeded for 47 % of the population associated with inhalation of PAHs with a maximum value of about 4 × 10-6.