Hasan Altiok

Spatial and temporal variation and air–soil exchange of atmospheric PAHs and PCBs in an industrial region

Abstract It was recently suggested that emissions of some persistent organic pollutants (POPs) are decreasing in former use regions due to emission reductions combined with uncontrolled export, at the expense of regions receiving these substances as obsolete products and wastes. Aliaga industrial region in Izmir, Turkey is one of the regions receiving POPs in the form of scrap iron and old ships to be scrapped. Ambient air samples were collected by passive sampling during four seasons in 2009 and 2010 (winter, spring, summer, and fall) at forty different sites in Aliaga to determine the spatial and seasonal variations of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Soil samples were also collected at the air sampling sites during the summer period. Phenanthrene was the most abundant PAH at all sites, and all samples were dominated by low to medium molecular weight PAHs, i.e., fluorene, fluoranthene and pyrene. The spatial distribution of ambient PAH concentrations indicated that the major PAH sources in the region were iron–steel plants, petroleum refinery, and ship dismantling plants. At residential sites, PAH concentrations were higher in winter indicating that wintertime concentrations were mainly affected by residential heating emissions. However, highest atmospheric PCBs concentrations were observed in summer, probably due to increased volatilization from their sources at higher temperatures. Low to medium molecular weight PCBs (tri–, tetra–, penta–CBs) were the most abundant compounds in air for all seasons. Results also indicated that iron–steel plants and ship dismantling facilities were the major PCB emitters in the region. A similar spatial variation was observed for soil PAH and PCB concentrations. Air and soil PAH and PCB concentrations were correlated significantly indicating the interaction of these compartments. Results of the fugacity ratio calculations indicated that local soils generally act as a sink throughout the year for medium to low volatility atmospheric PAHs and PCBs. However, during summer soil becomes a source, especially for volatile PAHs and PCBs.

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.

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.

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.

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.

Spatial variation of trace elements in seawater and sediment samples in a heavily industrialized region

Surface seawater and coastal sediment samples were collected concurrently at 22 sampling sites during two sampling periods in the Aliaga industrial region, Turkey. In the study area there are two major bays, with many ports belonging to a petrochemical plant, a petroleum refinery, scrap steel production plants, and a fertilizer plant. Samples were analyzed for 48 trace elements using an ICP-MS system. The concentrations of P, Al, Zn, Fe, Se, Mo, and Ba were found to be higher than those of the other elements in the seawater samples but with no significant spatial and temporal variations. Similarly, concentrations of Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, Sr, and Zn were high in sediment samples from almost all sampling sites. The concentrations of the elements Pb, Cd, Cr, Cu, Co, Sn, Mo, Ni, and Hg showed significant spatial variations due to different distances from industrial facilities. In order to determine the contribution of anthropogenic sources in sediment samples, the levels of pollution were evaluated using pollution indicators, enrichment factors and index of geoaccumulation. The effects on aquatic environments were also determined in accordance with the sediment quality guidelines. Principal component analysis was also employed to find out the factors affecting the elemental composition of the sediments. Principal component analysis indicated that the possible sources in the region were iron-steel production, refinery and petrochemical processes, ship breaking facilities, seawater, crustal sources and re-suspended dust.

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.