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To study the spatiotemporal variability of particle-bound polycyclic aromatic hydrocarbons (PAHs) and assess their carcinogenic potential in six contrasting urban environments in Greece, a total of 305 filter samples were collected and analyzed. Sampling sites included a variety of urban background, traffic (Athens, Ioannina and Heraklion), rural (Xanthi) and near-port locations (Piraeus and Volos). When considering the sum of 16 U.S. EPA priority PAHs, as well as that of the six EU-proposed members, average concentrations observed across locations during summer varied moderately (0.4–2.2 ng m−3) and independently of the population of each site, with the highest values observed in the areas of Piraeus and Volos that are affected by port and industrial activities. Winter levels were significantly higher and more spatially variable compared to summer, with the seasonal enhancement ranging from 7 times in Piraeus to 98 times in Ioannina, indicating the large impact of PAH emissions from residential wood burning. Regarding benzo(a)pyrene (BaP), an IARC Group 1 carcinogen and the only EU-regulated PAH, the winter/summer ratios were 24–33 in Athens, Volos, Heraklion and Xanthi; 60 in Piraeus; and 480 in Ioannina, which is afflicted by severe wood-burning pollution events. An excellent correlation was observed between organic carbon (OC) and benzo(a)pyrene (BaP) during the cold period at all urban sites (r2 > 0.8) with stable BaP/OC slopes (0.09–0.14 × 10−3), highlighting the potential use of OC as a proxy for the estimation of BaP in winter conditions. The identified spatiotemporal contrasts, which were explored for the first time for PAHs at such a scale in the Eastern Mediterranean, provide important insights into sources and controlling atmospheric conditions and reveal large deviations in exposure risks among cities that raise the issue of environmental injustice on a national level. [ABSTRACT FROM AUTHOR]

Kyanite-rich rock samples from Thassos Island, Greece, underwent beneficiation tests aiming to examine their potential as commercial refractory materials. The extracted material was compared to commercial samples of kyanite, andalusite and sillimanite. The experimental procedure combined mineral processing and material characterization. The mineral processing included grinding of the Thassos samples and grain size distribution, then gravity separation, using heavy liquid media (sodium polytungstate), and magnetic separation. Material characterization included XRF analysis on the bulk samples, XRD analysis on both the bulk and the commercial samples, and combined reflected light microscopy, SEM, XRF and XRD analysis on the final product. Gravity separation tests showed that the optimum liberation size of kyanite is any grain size finer than 500 μm, since coarser grain size fractions are characterized by elevated content of accessory minerals in the concentrates. Magnetic separation followed, removing the magnetic minerals from the concentrates, with ilmenite being a possible Ti-rich by-product to be recovered. The results indicate that the obtained percentage of kyanite reaches up to 95%. Furthermore, chemical analysis reveals that the composition of the processed material, in terms of concentration of alumina (and other major oxides), meets the standards of the Chinese and the American industry. It is therefore suggested that the Thassos kyanite-bearing assemblages constitute a promising resource that should be further tested in a semi-industrial scale, to fully establish their industrial potential. [ABSTRACT FROM AUTHOR]

Coastal landscapes are sensitive to changes due to the interplay between surface and submarine geological processes, climate variability, and relative sea level fluctuations. The sedimentary archives of such marginal areas record in detail the complex evolution of the paleoenvironment and the diachronic biota response. The Elefsis Bay is nowadays a landlocked shallow marine basin with restricted communication to the open Saronikos Gulf. A multi-proxy investigation of a high-resolution sediment core recovered from the deepest part of the basin offered a unique opportunity to record the paleoenvironmental and aquatic ecosystem response to climate and glacioeustatic sea level changes since the Late Glacial marine transgression. The retrieved sedimentary deposits, subjected to thorough palynological (pollen, non-pollen palynomorphs, dinoflagellates), micropaleontological (benthic foraminifera, calcareous nannoplankton, ostracods), and mollusc analyses, indicates isolation of the Elefsis Bay from the Saronikos Gulf and the occurrence of a shallow freshwater paleolake since at least 13,500 cal BP, while after 11,350 cal BP the transition towards lagoon conditions is evidenced. The marine transgression in the Elefsis Bay is dated at 7500 cal BP, marking the establishment of the modern marine realm. [ABSTRACT FROM AUTHOR]

The present study focuses on the palynological investigation of a sediment core (S2P) recovered from Elefsis Bay, in the western part of Attica Peninsula (southern Greece). Until now, there is quite scarce knowledge about the vegetation history of southern Greece during Late Glacial and Holocene due to a deficiency of long high-resolution pollen records. The analyzed gravity core is a unique continuous and well-dated pollen archive, providing the opportunity for the reconstruction of the plant landscape succession in southern Greece since Late Glacial. In order evidence for the vegetation response to climate oscillations and human impact to be derived, detailed analyses were conducted throughout the sedimentary sequence, spanning the last 13,500 years. The pollen data suggest that temperate deciduous, open oak woodlands of Late Glacial were fully expanded during the onset of Holocene, without any pronounced setback due to climate oscillations as it has been previously indicated by pollen archives from northern Greece. Following this period, Middle Holocene is characterized by the establishment of complex vegetation patterns, partly as the result of human activities, which seem to be the dominant vegetation shaping factor during Late Holocene. Overall, our pollen record highlights the vegetation transition during Late Glacial and Holocene in southern Greece, while offering valuable insight into the plant landscape prior to the first signs of human impact on the environment. [ABSTRACT FROM AUTHOR]