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.

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.

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.

Fast Formation of Nitro-PAHs in the Marine Atmosphere Constrained in a Regional-Scale Lagrangian Field Experiment.

Polycyclic aromatic hydrocarbons (PAHs) and some of their nitrated derivatives, NPAHs, are seemingly ubiquitous in the atmospheric environment. Atmospheric lifetimes may nevertheless vary within a wide range, and be as short as a few hours. The sources and sinks of NPAH in the atmosphere are not well understood. With a Lagrangian field experiment and modeling, we studied the conversion of the semivolatile PAHs fluoranthene and pyrene into the 2-nitro derivatives 2-nitrofluoranthene and 2-nitropyrene in a cloud-free marine atmosphere on the time scale of hours to 1 day between a coastal and an island site. Chemistry and transport during several episodes was simulated by a Lagrangian box model i.e., a box model coupled to a Lagrangian particle dispersion model, FLEXPART-WRF. It is found that the chemical kinetic data do capture photochemical degradation of the 4-ring PAHs under ambient conditions on the time scale of hours to 1 day, while the production of the corresponding NPAH, which sustained 2-nitrofluoranthene/fluoranthene and 2-nitropyrene/pyrene yields of (3.7 ± 0.2) and (1.5 ± 0.1)%, respectively, is by far underestimated. Predicted levels of NPAH come close to observed ones, when kinetic data describing the reactivity of the OH-adduct were explored by means of theoretically based estimates. Predictions are also underestimated by 1-2 orders of magnitude, when NPAH/PAH yields reported from laboratory experiments conducted under high NOx conditions are adopted for the simulations. It is concluded that NPAH sources effective under low NOx conditions, are largely underestimated.

Polybrominated diphenyl ethers (PBDEs) in background air around the Aegean: implications for phase partitioning and size distribution.

The occurrence and atmospheric behavior of tri- to deca-polybrominated diphenyl ethers (PBDEs) were investigated during a 2-week campaign concurrently conducted in July 2012 at four background sites around the Aegean Sea. The study focused on the gas/particle (G/P) partitioning at three sites (Ag. Paraskevi/central Greece/suburban, Finokalia/southern Greece/remote coastal, and Urla/Turkey/rural coastal) and on the size distribution at two sites (Neochorouda/northern Greece/rural inland and Finokalia/southern Greece/remote coastal). The lowest mean total (G + P) concentrations of ∑7PBDE (BDE-28, BDE-47, BDE-66, BDE-99, BDE-100, BDE-153, BDE-154) and BDE-209 (0.81 and 0.95 pg m-3, respectively) were found at the remote site Finokalia. Partitioning coefficients, K P, were calculated, and their linear relationships with ambient temperature and the physicochemical properties of the analyzed PBDE congeners, i.e., the subcooled liquid pressure (P L°) and the octanol-air partition coefficient (K OA), were investigated. The equilibrium adsorption (P L°-based) and absorption (K OA-based) models, as well as a steady-state absorption model including an equilibrium and a non-equilibrium term, both being functions of log K OA, were used to predict the fraction Φ of PBDEs associated with the particle phase. The steady-state model proved to be superior to predict G/P partitioning of BDE-209. The distribution of particle-bound PBDEs across size fractions < 0.95, 0.95-1.5, 1.5-3.0, 3.0-7.2, and > 7.2 µm indicated a positive correlation between the mass median aerodynamic diameter and log P L° for the less brominated congeners, whereas a negative correlation was observed for the high brominated congeners. The potential source regions of PBDEs were acknowledged as a combination of long-range transport with short-distance sources.

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.

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.

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.

Evaluation of a Conceptual Model for Gas-Particle Partitioning of Polycyclic Aromatic Hydrocarbons Using Polyparameter Linear Free Energy Relationships.

A model for gas-particle partitioning of polycyclic aromatic hydrocarbons (PAHs) was evaluated using polyparameter linear free energy relationships (ppLFERs) following a multiphase aerosol scenario. The model differentiates between various organic (i.e., liquid water-soluble (WS)/organic soluble (OS) organic matter (OM), and solid/semisolid organic polymers) and inorganic phases of the particulate matter (PM). Dimethyl sulfoxide and polyurethane were assigned as surrogates to simulate absorption into the above-mentioned organic phases, respectively, whereas soot, ammonium sulfate, and ammonium chloride simulated adsorption processes onto PM. The model was tested for gas and PM samples collected from urban and nonurban sites in Europe and the Mediterranean, and the output was compared with those calculated using single-parameter linear free energy relationship (spLFER) models, namely Junge-Pankow, Finizio, and Dachs-Eisenreich. The ppLFER model on average predicted 96 ± 3% of the observed partitioning constants for semivolatile PAHs, fluoranthene, and pyrene, within 1 order of magnitude accuracy with root-mean-square errors (RMSE) of 0.35-0.59 across the sites. This was a substantial improvement compared to Finizio and Dachs-Eisenreich models (37 ± 17 and 46 ± 18% and RMSE of 1.03-1.40 and 0.94-1.36, respectively). The Junge-Pankow model performed better among spLFERs but at the same time showed an overall tendency for overestimating the partitioning constants. The ppLFER model demonstrated the best overall performance without indicating a substantial intersite variability. The ppLFER analysis with the parametrization applied in this study suggests that the absorption into WSOSOM could dominate the overall partitioning process, while adsorption onto salts could be neglected.

Investigation of spatial distributions and sources of persistent organic pollutants (POPs) in a heavily polluted industrial region using tree components.

Spatial distributions of persistent organic pollutants (POPs) were investigated in Iskenderun industrial region in Turkey. POP concentrations were measured in different tree components (i.e., pine needle, branch, bark, and stem) collected at several industrial and background sites (n = 27). Also, air, litter, and soil samples were analyzed to determine the relationship of atmospheric pollutants with tree components, litter, and soil. Spatial variation of measured concentrations and factor analysis showed that the iron-steel plants are the most important POP sources in Iskenderun area. Correlations of ambient air levels to those measured in soil, litter, and tree components were significant showing that POPs are exchanged between atmosphere and these compartments. Results have suggested that tree components, litter and soil could be used to determine the spatial distributions and sources of atmospheric POPs in a region. POP quantities (mg/ha) accumulated in different tree components, litter, and soil were also predicted. Generally, the highest quantities were accumulated by stem and needles. In terms of overall inventory, including trees, litter and soil, the highest accumulated quantities were found in soil followed by trees and litter, indicating that in addition to soil, vegetation is a notable reservoir accumulating POPs. Ambient air POP concentrations were also estimated using a bark/air partitioning model. The estimated/measured ratios were close to 1.0 for several compounds and the results showed that the atmospheric POP concentrations could be estimated from the bark measurements within factors of 0.23-3.07, 1.02-6.67, 0.63-7.44, 1.07-3.37 for polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated naphthalenes, and polybrominated diphenyl ethers, respectively.

Investigation of spatial and historical variations of air pollution around an industrial region using trace and macro elements in tree components.

Several trace and macro elements (n=48) were measured in pine needle, branch, bark, tree ring, litter, and soil samples collected at 27 sites (21 industrial, 6 background) to investigate their spatial and historical variation in Aliaga industrial region in Turkey. Concentrations generally decreased with distance from the sources and the lowest ones were measured at background sites far from major sources. Spatial distribution of anthropogenic trace elements indicated that their major sources in the region are the iron-steel plants, ship-breaking activities and the petroleum refinery. Patterns of 40 elements that were detected in most of the samples were also evaluated to assess their suitability for investigation of historical variations. Observed increasing trends of several trace and macro elements (As, Cr, Fe, Mo, Ni, V, Cu, Pb, Sb, Sn, and Hg) in the tree-ring samples were representative for the variations in anthropogenic emissions and resulting atmospheric concentrations in Aliaga region. It was shown that lanthanides (La, Ce, Pr, Nd, Sm, Gd, Dy, Er, Yb) could also be used for the investigation of historical variations due to specific industrial emissions (i.e., petroleum refining). Results of the present study showed that tree components, litter, and soil could be used to determine the spatial variations of atmospheric pollution in a region while tree rings could be used to assess the historical variations.

Determination of the personal, indoor and outdoor exposure levels of inorganic gaseous pollutants in different microenvironments in an industrial city.

We measured SO2, NO2 and O3 concentrations during the summer and winter in Kocaeli, Turkey. The sampling was carried out indoors and outdoors at homes, schools and offices. Personal samplers were also used to determine personal exposures to these pollutants. High NO2 and SO2 concentrations were observed in outdoor samples collected close to locations characterized by heavy urban traffic. Concentrations of O3, on the other hand, were higher in rural areas around the city due to ozone distillation. For both sampling periods, the concentrations of outdoor SO2 and O3 were higher than for indoor and personal samples; however, the NO2 concentrations were higher in indoor and personal samples, indicating that outdoor sources significantly contribute to indoor SO2 and O3 levels and that indoor NO2 concentrations are primarily modulated by sources within buildings. Seasonal variations in pollutant concentrations showed statistically significant differences. Indoor and outdoor concentrations of NO2 and SO2 measured in the winter were higher than the levels measured in the summer; O3 concentrations, on the other hand, exhibited the opposite trend. Active-to-passive concentration ratios for NO2, SO2 and O3 were 0.99, 1.08 and 1.16, respectively; the corresponding outdoor ratios were 0.95, 0.99 and 1.00.

Biomonitoring the spatial and historical variations of persistent organic pollutants (POPs) in an industrial region.

Several persistent organic pollutants (POPs) like polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and polybrominated diphenyl ethers (PBDEs) were measured in needle, branch, bark, and tree ring samples in pine samples collected at 27 sites (21 industrial, 6 background) in Aliaga industrial region in Turkey. Soil, litter, and air samples were also collected to investigate the relationships between the air and soil, litter, and tree components. Concentrations decreased with distance from the sources and the lowest ones were measured at background sites. The spatial distribution of POPs indicated that the major sources in the region are the iron-steel, ship-breaking, petrochemical plants and the petroleum refinery. Significant correlations between the air concentrations and, soil, litter, and tree components indicated the interaction of these compartments with air. Observed increasing trends of POPs in the tree-ring samples were representative for the variations in anthropogenic emissions and resulting atmospheric concentrations in Aliaga region. These results indicated that tree components, litter and soil could be used to determine the spatial variations while tree rings could be used to investigate the historical trends of atmospheric POPs in a region. POP amounts (mg/ha) stored in different tree components, litter, and soil were also inventoried. Among the tree components, generally, the highest amounts were stored in the stem followed by needles. For the overall inventory, the highest amounts were stored in soil for PCNs, PBDEs, and PCBs while highest PAH amounts were stored in trees, indicating that in addition to soil, vegetation is also an important reservoir for POPs.

Spatial distribution and source identification of trace elements in topsoil from heavily industrialized region, Aliaga, Turkey.

Topsoil samples (n = 40) were collected from a heavily industrialized region in Turkey. The region includes several scrap processing iron-steel plants with electric arc furnaces (EAFs), a petroleum refinery, a petrochemical complex, steel rolling mills, a natural gas-fired power plant, ship-breaking yards and very dense transportation activities. The region has undergone a rapid transition from an agricultural region to a heavily industrialized region in the last three decades. Collected soil samples were analyzed for 48 trace elements using inductively coupled plasma-mass spectrometry (ICP-MS). The elemental distribution pattern in the region indicated that Nemrut area with dense iron-steel production activities was a hotspot for elemental pollution. In addition to crustal elements, concentrations of anthropogenic trace elements (i.e., Fe, Zn, Pb, Mn, Cu, Cd, Cr and Mo) were very high in the area influencing many parts of the region. Elemental compositions of fugitive sources polluting the soil (i.e., paved and unpaved roads, slag piles, EAFs filter dust piles and coal piles) were also determined. The methods (enrichment factors [EFs] and the index of geoaccumulation [Igeo]) used for determination of pollution status of soil showed that Cr, Ag, Zn, As and Pb were the strongly contaminating elements for the region. Principal component analysis (PCA) clearly indicated that anthropogenic sources (steel production, refinery and petrochemical processes and traffic) were important sources in this region.

Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: determination of specific emission rates for thirty-one tree species.

Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO2) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 µmol/m(2)s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 µg/gh was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 µg/gh. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta-pinene and beta-myrcene were generally emitted by coniferous species. Oxygenated compounds were the third most prominent BVOC group and sesquiterpenes had slightly lower contributions.

Electric arc furnaces for steel-making: hot spots for persistent organic pollutants.

Persistent organic pollutant (POP) concentrations were measured in stack-gases of ferrous scrap processing steel plants with electric arc furnaces (EAFs) (n = 5) in Aliaga, Izmir, Turkey and in air (n = 11) at a site near those plants. Measured stack-gas concentrations for the four plants without scrap preheating (611 +/- 311, 165,000 +/- 285,000, and 33 +/- 3 ng m(-3), average +/- SD for sigma41PCBs, sigma16PAHs, and sigma7PBDEs, respectively) indicated that they are significant sources for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). POP emissions from the plant with scrap preheating were significantly higher (13 500, 445 000, and 91 ng m(-3) for sigma41PCBs, sigma16PAHs, and sigma7PBDEs, respectively). It was also shown that the steel plants emit considerable amounts of fugitive POPs in particle-phase. Estimated emissions using the emission factors generated in this study and the production amounts suggested that the steel plants with EAFs may significantly contribute to local and global PAH, PCB, and PBDE emissions. Several other compounds (aromatic and aliphatic hydrocarbons, oxygen, sulfur, nitrogen, and chlorine-containing organic compounds, n = 49) were identified and determined semiquantitatively in the stack-gas and ambient air samples. Ambient air concentrations (62 +/- 35, 320 +/- 134 ng m(-3), 1451 +/- 954 pg m(-3), for sigma41PCBs, sigma16PAHs, and sigma7PBDEs, respectively) were significantly higher than those measured previously around the world and in the region, further confirming that the steel plants with EAFs are "hot spots" for POPs.