A novel approach for characterization of polycyclic aromatic hydrocarbon (PAH) pollution patterns in sediments from Guanabara Bay, Rio de Janeiro, Brazil

A novel multivariate method based on principal component analysis of pre-processed sections of chromatograms is used to characterize the complex PAH pollution patterns in sediments from Guanabara Bay, Brazil. Five distinct sources of 3- to 6-ring PAHs could be revealed. The harbour is the most contaminated site in the bay, its plume stretches in a South West to North East direction and the chemical profile indicates mainly pyrogenic sources mixed with a fraction of high-molecular-weight petrogenic PAHs. Rio São João de Meriti is the second largest source of PAHs, and introduces mainly a fraction of low-molecular-weight petrogenic PAHs from the western region of Rio de Janeiro. The sites close to the ruptured pipeline at the Duque de Caxias Refinery show a distinctive pollution pattern indicating a heavy petroleum fraction. The method also led to the identification of new potential indicator ratios also involving coeluting peaks (e.g., triphenylene and chrysene).     

Ambient monitoring of asbestos in selected Italian living areas

This paper presents the results of an intensive monitoring activity of the particulate, fall-out and soil of selected living areas in Italy with the aim to detect the asbestos concentration in air and subsequent risk of exposure for the population in ambient living environments, and to assess the nature of the other mineral phases composing the particulate matrix. Some areas were sorted out because of the presence of asbestos containing materials on site whereas others were used as blank spots in the attempt to detect the background environmental concentration of asbestos in air. Because the concentration of asbestos in ambient environments is presumably very low, and it is well known that conventional low–medium flow sampling systems with filters of small diameter (25 mm) may collect only a very small fraction of particulate over a short period, for the first time here, an intense monitoring activity was conducted with a high flow sampling system. The high flow system requires the use of large cellulose filters with the advantage that, increasing the amount of collected dust, the probability to collect asbestos fibers increases. Both the protocol of monitoring and analysis are novel and prompted by the need to increase the sensitivity towards the small number of expected fibers. With this goal, the collection of fall-out samples (the particulate falling into a collector filled with distilled water during the monitoring shift) and soil samples was also accomplished. The analytical protocol of the matrix particulate included preliminary X-ray powder diffraction (XRPD), optical microscopy and quantitative electron microscopy (SEM and TEM). Correlations with climatic trends and PM10 concentration data were also attempted.The surprising outcome of this work is that, despite the nature of the investigated site, the amount of dispersed asbestos fibers is very low and invariably lower than the theoretical method detection limits of the SEM and TEM techniques for identification and counting of asbestos fibers. The results are compared to the literature data worldwide and an updated model for asbestos fibers dispersion in ambient environments is proposed.     

Fungitoxicity of lyophilized and spray-dried garlic extracts

Among the compounds discussed for anti-microbial and anti-fungal use allicin (allylthiosulfinate, diallyl disulfide-S-monoxide), an active ingredient of garlic, has attracted considerable attention. The objective of this study is to determine the antifungal activity of a local garlic ecotype (Voghiera) extracts against different pathogens. Primary screening was carried out by the agar plates technique using ethanol garlic extract at four final concentrations against the following organisms: Alternaria alternata, Aspergillus spp., Colletotrichum acutatum, Didymella bryoniae, Fusarium culmorum, Fusarium avenaceum, Fusarium gramineareum, Gliocladium roseum 47, Pythium splendens, Rhizoctonia solani, Sclerotium rolfsii, Stemphylium vesicarium, Trichoderma longibranchiatum, and Botrytis cinerea. Secondary screening was carried out using a lyophilized and a spray-dried preparation at different concentrations against the organisms selected for the high inhibition garlic effect in the primary screening and compared with the commercial fungicides mancozeb and iprodione. The best results were observed for the spray-dried garlic compound that showed a good fungicidal activity at the concentration of 1.5 g/10 mL while lyophilized garlic at the same concentration exhibited less inhibition activity against the four fungi analyzed in the second screening.     

Noninvasive characterization of the Trecate (Italy) crude-oil contaminated site: links between contamination and geophysical signals

The characterization of contaminated sites can benefit from the supplementation of direct investigations with a set of less invasive and more extensive measurements. A combination of geophysical methods and direct push techniques for contaminated land characterization has been proposed within the EU FP7 project ModelPROBE and the affiliated project SoilCAM. In this paper, we present results of the investigations conducted at the Trecate field site (NW Italy), which was affected in 1994 by crude oil contamination. The less invasive investigations include ground-penetrating radar (GPR), electrical resistivity tomography (ERT), and electromagnetic induction (EMI) surveys, together with direct push sampling and soil electrical conductivity (EC) logs. Many of the geophysical measurements were conducted in time-lapse mode in order to separate static and dynamic signals, the latter being linked to strong seasonal changes in water table elevations. The main challenge was to extract significant geophysical signals linked to contamination from the mix of geological and hydrological signals present at the site. The most significant aspects of this characterization are: (a) the geometrical link between the distribution of contamination and the site’s heterogeneity, with particular regard to the presence of less permeable layers, as evidenced by the extensive surface geophysical measurements; and (b) the link between contamination and specific geophysical signals, particularly evident from cross-hole measurements. The extensive work conducted at the Trecate site shows how a combination of direct (e.g., chemical) and indirect (e.g., geophysical) investigations can lead to a comprehensive and solid understanding of a contaminated site’s mechanisms.     

Metal and metallothionein concentrations in Paracentrotus lividus from Amvrakikos gulf (Ionian Sea-Greece)

Concentrations of Cd, Cu, Cr, Ni, Zn, Fe and metallothioneins (MTs) were measured in the gonads of Paracentrotus lividus from Amvrakikos gulf (Ionian Sea, Greece). Three natural populations were selected; two of them, growing inside the gulf (Agios Thomas and Koronisia), presented higher density and smaller body size than the population living in a coastal area just outside the gulf (Mytikas). Metal and MT levels were not elevated, with the exception of Zn, showing high values related to the reproduction stage of the sea urchins. Significant geographical variations were recorded in the concentrations of Cu, Zn, Cd, Cr and MTs. The highest mean and maximum values of Cu, Zn and MTs were recorded in Agios Thomas while Cd and Cr were higher in Mytikas population. Copper, Zn, Fe and MT concentrations were negatively correlated to the sea urchin body size, while a positive concentration-size relationship was observed for Cd. Although all studied populations grow in a low metal level marine environment, urchins with smaller body size living in a food limited marine environment showed higher gonadosomatic index, metal concentrations and MT levels in their gonads (Agios Thomas and Koronisia) than larger specimens growing in a food unlimited area (Mytikas).     

Numerical Model Inter-comparison for Wind Flow and Turbulence Around Single-Block Buildings

Wind flow and turbulence within the urban canopy layer can influence the heating and ventilation of buildings, affecting the health and comfort of pedestrians, commuters and building occupants. In addition, the predictive capability of pollutant dispersion models is heavily dependent on wind flow models. For that reason, well-validated microscale models are needed for the simulation of wind fields within built-up urban microenvironments. To address this need, an inter-comparison study of several such models was carried out within the European research network ATREUS. This work was conducted as part of an evaluation study for microscale numerical models, so they could be further implemented to provide reliable wind fields for building energy simulation and pollutant dispersion codes. Four computational fluid dynamics (CFD) models (CHENSI, MIMO, VADIS and FLUENT) were applied to reduced-scale single-block buildings, for which quality-assured and fully documented experimental data were obtained. Simulated wind and turbulence fields around two surface-mounted cubes of different dimensions and wall roughness were compared against experimental data produced in the wind tunnels of the Meteorological Institute of Hamburg University under different inflow and boundary conditions. The models reproduced reasonably well the general flow patterns around the single-block buildings, although over-predictions of the turbulent kinetic energy were observed near stagnation points in the upwind impingement region. Certain discrepancies between the CFD models were also identified and interpreted. Finally, some general recommendations for CFD model evaluation and use in environmental applications are presented.     

Sustainability and New Models of Consumption: The Solidarity Purchasing Groups in Sicily

European society, with its steadily increasing welfare levels, is not only concerned with food (safety, prices), but also with other aspects such as biodiversity loss, landscape degradation, and pollution of water, soil, and atmosphere. To a great extent these concerns can be translated into a larger concept named sustainable development, which can be defined as a normative concept by). Sustainability in the food chain means creating a new sustainable agro-food system while taking the institutional element into account. While different concepts of sustainability abound, in recent years, spontaneous groups of consumers called solidarity purchase groups (SPG) have been developing. In short, they are characterized by an economy that is not necessarily local, but ethical and equitable, where social and economic territorial relations tend to develop districts and networks. One of the main characteristics of a SPG is the direct relationships between small farms and their customers; a relationship that is characterized by consumer participation and farmer specialization. This study aims to address issues related to organizational frameworks, at farm and chain level, and to assess those elements that lead to consumer choice and satisfaction.     

Assessment of Coastal Vulnerability Through the Use of GIS Tools in South Sicily (Italy)

This study assessed coastal erosion vulnerability along a 90-km sector, which included both erosional and accretionary beaches, and different levels of human occupation. Two aerial photogrammetric flights were used to reconstruct coastal evolution between 1977 and 1999. During this period, extensive accretion was recorded updrift of human structures at harbors and ports, e.g., Scoglitti (105.6 m), Donnalucata (52.8 m), and Pozzallo (94.6 m). Conversely, erosion was recorded in downdrift areas, with maximum values at Modica Stream mouth (63.8 m) and Point Castellazzo (35.2 m). Assessments were subsequently divided into four categories ranging from “high erosion” to “accretion.” Several sources were examined to assess human activities and land use. The latter was mapped and divided into four categories, ranging from “very high” to “no capital” land use. Subsequently, coastal erosion vulnerability was assessed by combining land use categories with recorded coastline behavior. Results showed “very high” to “high” vulnerability along 5.8% and 16.6%, respectively, of the littoral, while 20.9% and 56.7%, respectively, was found to exhibit “medium” and “low/very low” vulnerability. A very good agreement between predicted coastal vulnerability and coastal trend had been observed over recent years. Furthermore, several human structures and activities are located within the “imminent collapse zone (ICZ)” which reached maximum values of 17.5 m at Modica Stream and 13.5 m at Point Braccetto.     

A methodology for assessing the maximum expected radon flux from soils in northern Latium (central Italy)

Northern Latium (Italy) is an area where the Rn risk rate is potentially high because of the extensive outcropping of Neogene U-rich volcanics and the presence of major active tectonic lineaments. The lack of data on Rn risk rates in that area, which is undergoing major urban and industrial development, has prompted this study. It proposes a methodology to evaluate the maximum potential diffusive Rn flux from soils based on the measurement of ²²⁶Ra, ²³²Th and ⁴⁰K activities by γ-ray spectrometry, and the measurement of main soil parameters influencing the Rn emanation. This methodology provides a simple, reliable and low-cost tool for drawing up radon flux maps useful to both public planners and private individuals, who want to operate safely in the study area. The proposed methodology may also be applied to other geographic areas outside the prescribed study area.     

Accumulation and metal fluxes in the central Venice Lagoon during the last century

Samples from 18 short sediment cores were analyzed for major and trace metals (Al, Fe, Ca, K, Mg, Mn, Si, Ti, Pb, Zn, Cu, Ni, and Cr), ²¹⁰Pb, ¹³⁷Cs, total organic carbon, grain size, and mineralogical composition to find the record of major environmental changes, either natural or anthropogenic, and to establish their chronologies. Some sediments are characterized by nearly constant composition over time, but others clearly show signs of an increasing marine influence, as an increase of the carbonate contents, after the opening of the Malamocco-Marghera Canal in 1969. These changes sometimes obscure the real pattern of pollutants and tracers, which is revealed by normalization against Al. Zn is the most important contaminant, with concentration factors up to 9.3 times the background level, and the most contaminated sediments are those within a few kilometers from the industrial district of Porto Marghera. ²¹⁰Pb activity-depth profiles were used to calculate apparent accumulation rates that provide a basis for the assessment of metal fluxes. The sediments of several sites show a significant increase in anthropogenic metal contamination starting from the second decade of last century, with maximum inputs from 1930 to 1970. The decrease of heavy metal concentrations observed in surficial sediments of some sampling sites could be related to a recent reduction of pollutant inputs.