Commuter exposure to particle-bound polycyclic aromatic hydrocarbons in Thessaloniki,Greece

Environmental Science and Pollution Research - Commuters are exposed to high air pollution levels daily, especially in areas with dense traffic. This study examines the commuter’s exposure to...     

Spatiotemporal variation of odor-active VOCs in Thessaloniki,Greece: implications for impacts from industrial activities

Environmental Science and Pollution Research - A yearlong study of odor-active VOCs was carried out in the northwestern district of the city of Thessaloniki, Greece, which is in close vicinity to a...     

Innovative aspects of environmental chemistry and technology regarding air,water, and soil pollution

Environmental Science and Pollution Research -     

Chemical composition and mass closure of ambient PM10 at urban sites

The chemical composition of PM10 was studied during summer and winter sampling campaigns conducted at two different urban sites in the city of Thessaloniki, Greece (urban-traffic, UT and urban-industrial, UI). PM10 samples were chemically analysed for minerals (Si, Al, Ca, Mg, Fe, Ti, K), trace elements (Cd, Cr, Cu, Mn, Pb, V, Zn, Te, Co, Ni, Se, Sr, As, and Sb), water-soluble ions (Cl^?, NO₃^?, SO₄^2?, Na⁺, K⁺, NH₄⁺, Ca²⁺, Mg²⁺) and carbonaceous compounds (OC, EC). Spatial variations of atmospheric concentrations showed significantly higher levels of minerals, some trace metals and TC at the UI site, while at the UT site significantly higher levels of elements like Cd, Ba, Sn, Sb and Te were observed. Crustal elements, excepting Ca at the UI site, did not exhibit significant seasonal variations at any site pointing to constant emissions throughout the year. In order to reconstruct the particle mass, the determined components were classified into six classes as follows: mineral matter (MIN), trace elements (TE), organic matter (OM), elemental carbon (EC), sea salt (SS) and secondary inorganic aerosol (SIA). Good correlations with slopes close to 1 were found between chemically determined and gravimetrically measured PM10 masses for both sites. According to the chemical mass closure obtained, the major components of PM10 at both sites were MIN (soil-derived compounds), followed by OM and SIA. The fraction unaccounted for by chemical analysis comprised on average 8% during winter and 15% during summer at the urban-industrial site, while at the urban-traffic site the percentages were 21.5% in winter and 4.8% in summer.     

An investigation on the physical,chemical and ecotoxicological characteristics of particulate matter emitted from light-duty vehicles

Particulate matter (PM) emitted from three light-duty vehicles was studied in terms of its physicochemical and ecotoxicological character using Microtox^® bioassay tests. A diesel vehicle equipped with an oxidation catalyst emitted PM which consisted of carbon species at over 97%. PM from a diesel vehicle with a particle filter (DPF) consisted of almost equal amounts of carbon species and ions, while a gasoline vehicle emitted PM consisting of ～90% carbon and ～10% ions. Both the DPF and the gasoline vehicles produced a distinct nucleation mode at 120 km/h. The PM emitted from the DPF and the gasoline vehicles was less ecotoxic than that of conventional diesel, but not in direct proportion to the emission levels of the different vehicles. These results indicate that PM emission reductions are not equally translated into ecotoxicity reductions, implying some deficiencies on the actual environmental impact of emission control technologies and regulations.     

Wintertime size distribution of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the urban environment: Street- vs rooftop-level measurements

The size distribution of ambient air particles and associated organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) including hexachlorocyclohexanes (HCHs), DDT and metabolites, etc., was investigated at a traffic-impacted site of Thessaloniki, Greece. Investigation took place during wintertime of 2006 at two heights above ground: at the street level (1.5 m) and at the rooftop level (15 m). Size-resolved samples (<0.95 μm, 0.95–1.5 μm, 1.5–3 μm, 3–7.5 μm and >7.5 μm) were concurrently collected from the two height levels using five-stage high volume cascade impactors. At both heights, particle mass exhibited bimodal distribution with peaks in the 0.95–1.5 μm and the 3–7.5 μm size fractions, whereas most organic pollutants exhibited one peak at 0.95–1.5 μm. Apart from the 0.95–1.5 μm fraction, particle concentrations of all size ranges were significantly higher at the street level than at the rooftop as a result of more intensive vehicular emissions and road dust resuspension. On the contrary, the concentrations of most organic pollutants did not differentiate significantly between the two elevations.     

Persistent organic pollutants (POPs) in the conventional activated sludge treatment process: model predictions against experimental values

The FATE and treatibility estimator (FATE) model, developed by the United States Environmental Protection Agency was used for the prediction of the FATE of 26 persistent organic pollutants (POPs), i.e. 7 PCBs and 19 organochlorine compounds (OCs), during the conventional activated sludge treatment process applied in the waste water treatment plant (WWTP) of Thessaloniki, Greece. The removal rates predicted by the model for the primary and the secondary treatment stages were found to differ substantially from those experimentally measured. When the overall treatment was considered, the differences between measured and model predicted removals were within acceptable limits of confidence. Possible reasons that might cause deviations from experimental values were suggested to be the wastewater content in dissolved organic carbon (DOC), and/or the low concentrations of POPs in untreated wastewater.     

Size distribution of airborne particulate matter and associated heavy metals in the roadside environment

The size distributions of airborne particulate matter (PM) and associated heavy metals Pb, Cd, Ni, Cr, V, Mn, Cu and Fe in different inhalable fractions (< 0.8 microm, 0.8-1.3 microm, 1.3-2.7 microm, 2.7-6.7 microm and > 6.7 microm) were determined at a traffic-orientated urban site in the city of Thessaloniki, northern Greece. The airborne PM displayed a bimodal distribution with most of the mass (52%) contained in the submicron size range (< 0.8 microm) and an additional minor mode (20%) in the coarse size fraction (> 6.7 microm). Characteristic size distributions of heavy metals allowed identification of three main behavioral types: (a) metals whose mass was resided mainly within the accumulation mode (Pb,Cd), (b) those which were distributed between fine, intermediate and coarse modes (Ni,Cu,Mn), and (c) those which were mainly found within particles larger than 2.7 microm in diameter (Fe). The mean mass median aerodynamic diameter (MMAD) of PM was found at 0.85+/-0.71 microm, while the mean MMADs of heavy metals followed the order Pb (0.96 +/- 0.71 microm) < Cd (1.14 +/- 0.82 microm) < V (1.38 +/- 0.63 microm) < Ni (1.45 +/- 0.88 microm) < Cu (2.04 +/- 0.77 microm) < Mn (2.61 +/- 1.23 microm) < Cr (2.91 +/- 1.40 microm) < Fe (3.82 +/- 0.88 microm). The measured distributions are believed to result from a combination of processes including local anthropogenic and natural sources, such as traffic, industrial emissions and resuspension of road dust.     

Distribution of persistent organic pollutants, polycyclic aromatic hydrocarbons and trace elements in soil and vegetation following a large scale landfill fire in northern Greece

Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), including hexaclorocyclohexanes (HCHs) and DDTs, as well as trace elements were determined in soil and vegetation samples collected from the surrounding area of the landfill "Tagarades", the biggest in northern Greece, following a large scale fire involving approximately 50,000 tons of municipal waste. High concentrations of total PAHs, PCBs and heavy metals were found inside the landfill (1475 microg kg(-1) dw, 399 microg kg(-1) dw and 29.8 mg kg(-1) dw, respectively), whereas concentrations in the surrounding soils were by far lower ranging between 11.2-28.1 microg kg(-1) dw for PAHs, 4.02-11.2 microg kg(-1) dw for PCBs and 575-1207 mg kg(-1) dw for heavy metals. The distribution of HCHs and DDTs were quite different since certain soils exhibited equal or higher concentrations than the landfill. In vegetation, the concentrations of PAHs, PCBs, HCHs and DDTs ranged from 14.1-34.7, 3.64-25.9, 1.41-32.1 and 0.61-4.03 microg kg(-1) dw, respectively, while those of heavy metals from 81 to 159 mg kg(-1) dw. The results of the study indicated soil and vegetation pollution levels in the surroundings of the landfill comparable to those reported for other Greek locations. The impact from the landfill fire was not evident partially due to the presence of recent and past inputs from other activities (agriculture, vehicular transport, earlier landfill fires).     

Toxicity and heavy metal contamination of surficial sediments from the Bay of Thessaloniki (Northwestern Aegean Sea) Greece

Surficial sediments (the fraction < 2000 microm) from the Bay of Thessaloniki, in the Northwestern Aegean Sea, Greece were examined for heavy metal and organic carbon contents, as well as for acute LUMIStox toxicity of pore waters (PWs), wet sediment elutriates (WSEs) and dry sediment elutriates (DSEs) obtained from the solid material remaining after PW extraction. WSEs where not toxic. EC20/50 values could be measured in some DSE and PW samples. In all sediment samples, the DSE toxicity was greater than the corresponding PW toxicity. Sediment concentrations of total and labile Cd, Pb, Cu, Cr, Zn, Mn, Ni and Fe were determined and evaluated in relation to sediment quality guidelines. Pollution levels ranged from low to high for certain metals. A misfit between sediment toxicities calculated from heavy metal concentrations and those biologically measured was observed. Toxicity values were in general poorly correlated with sediment's heavy metal or organic carbon content. As significant correlation was however found between the DSE toxicity with total Ni and labile Fe, as well as for the PW toxicity with total Ni, labile Fe and labile Cr.