Search

Abstract: The primary objective of this study was to examine the chemical speciation of polycyclic aromatic hydrocarbons (PAHs) found in sediments endowed with different characteristics. To achieve this purpose and because the nature of the sediments influences the distribution of PAHs, we have analyzed four different types of sediments. To study the role of organic matter in the sequestration of PAHs, we fractionated humic substances into humic acids and humin–mineral fractions. After their separation and purification, the humic components were examined for their sorptive reactivity by extracting them with organic solvents; these extracts were subsequently subjected to GC/MS analysis. Our results show that PAHs are distributed between labile and sequestered fractions in sediments. A slower uptake of PAHs occurs when the sequestered fraction is formed, and this process can be prolonged and may be influenced by the characteristics if the sediment. Our study suggests that organic contaminants are available in muddy sediments for a longer period of time than in sandy sediments. [ABSTRACT FROM AUTHOR]

Studies on indoor pollution are important since people spend more than 80% of their time indoor environments. In this work the method for PAHs analysis in indoor dust (used as passive sampler) and the results relative to samples collected in the area of Palermo are reported. Dust samples for analysis were collected from 45 indoor environments. Total PAHs concentrations in indoor dusts ranged from 36 to 34453μgkg−1 d.w. To correlate indoor and outdoor pollution we analyze, also, the particulate matter and PAHs levels samples collected in four stations. The percentage measured in indoor dusts results more low than that found outside. The values of isomeric ratios for the different samples were used to individuate the predominant PAHs sources. [Copyright &y& Elsevier]

The distribution of selected Polycyclic Aromatic Hydrocarbons (PAHs) in surface sediments and clams of marine coastal lagoons, called Ganzirri, located at the Sicilian coast of the Messina's strait, has been investigated by GCIMS analysis with Selected Ion Monitoring (SIM) mode. The lagoon is characterized by abundant organic detritus, deriving from aquagenic and anthropogenic inputs. Anoxic/reduced conditions of sediments make them a preferential site for uptake and preservation of PAHs. The investigations have been performed on the 16 PAHs recommended by US-EPA as priority pollutants to be monitored in the framework of environmental quality control. The sediment PAR concentrations ranged from 135 to 1650 μg/kg dry matrix. The total concentrations of PAHs in clams ranged from 60 to 1427 μg/kg d.w. The relative standard deviation (RSD) for all samples of the concentration replicates of individual compounds ranged from 10% to 25%. The resulting distributions and ratios of specific compounds have been discussed in terms of sampling location and origin of contaminants. The results obtained show that levels of contamination are not homogeneous throughout the stations. In the Ganzirri Lagoon, the bioavailability of hydrophobic organic compounds, such as PAHs, seems to be mainly governed by chemical characteristics of the contaminants. Pyrolytic compounds (penta- and hexa-aromatics) are not readily available. In contrast, petroleum hydrocarbons (some tetra-aromatics) are accumulated by clams to a great extent. From an eco-toxicological point of view, the aquatic ecosystem investigated appears to be moderately polluted. [ABSTRACT FROM AUTHOR]

The leaves of Pelargonium zonale have been chosen because this plant is widespread in both the Mediterranean metropolitan and peripheral areas. The paper describes the analytical method, and the results concerning the determination of PAHs in Pelargonium leaves collected in the Palermo area, and their possible origins. The GC-MS method was applied, since identification of all the different compounds with spectra libraries is possible. Samples were analyzed for 22 PAHs. The reported analytical method is complete within 2 hours, and more convenient than that of other researches. Total PAH concentrations in leaves varied between 24–357 μg/kg d.w. The relative abundance of the analyzed PAHs can be used to elucidate the sources. PAH concentrations were positively correlated to those of particulate measured by traditional methods. The results clearly indicate that the chosen PAH levels in Pelargonium leaves offer the possibility to assess the quality of air in determined geographical areas. The city of Palermo is prone to a rather high level of atmospheric pollution, in particular in the zones with heavy traffic. Industrial activity is widespread in the area, but not an important source of the pollutants studied here. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines the presence, distribution, nature and sources of 22 Aromatic Hydrocarbons (PAHs), which are important environmentally and toxicologically, in sediments from the Stagnone coastal lagoon at Marsala (Italy). Analysis was performed by gas chromatography/mass spectrometry (GC/MS) with selected ion monitoring (SIM). The total concentration of polycyclic aromatic hydrocarbons ranged from 72 to 18381 μg/kg of dry matrix. The relative standard deviation (RSD) of the replicates on the concentrations of individual compounds ranged from 5% to 20%. The accuracy of method was estimated by analyzing “blank” samples added of known quantities of analytes and the recover percentage was 88±9%. The detection limit (LOD) of analytical procedure was less than 0.2 μg/kg d.w. for all analytes. The quantification limit (LOQ) of analytical procedure was less than 0.7 μg/kg d.w. The resulting distributions and weight ratios of specific compounds are discussed in terms of sampling location and origin of organic matter. A comparison with other studies of total PAHs suggests that the levels are within the concentration ranges already reported by other authors. From an eco-toxicological point of view, total PAH concentrations at seven out of the eight sites studied represent a relatively clean environment when compared to other sites. Organic matter content and PAH concentrations were found to be correlated and the compounds present in Stagnone sediments were shown to be mainly of pyrolitic origin, while a negligible quantity of PAHs may derive from biogenic sources since all the sediments contain perylene traces. There is no evidence of coal-tar contamination. Cluster analysis was carried out in order to discriminate between different PAH origins. [Copyright &y& Elsevier]