Pasquale Avino

Monoaromatic compounds in ambient air of various cities: a focus on correlations between the xylenes and ethylbenzene

Speciation of o-xylene, m-xylene, p-xylene and ethylbenzene was performed by gas chromatography from ambient air and liquid fuel samples collected at various locations in 19 cities in Europe, Asia and South America. The xylenes mixing ratios were compared to each other from the various locations, which included urban air, traffic air and liquid fuel. For all samples, the xylenes exhibited robust correlations, and the slopes remained constant. The m-xylene/p-xylene ratio was found to be 2.33±0.30, and the m-xylene/o-xylene ratio was found to be 1.84±0.25. These ratios remain persistent even in biomass combustion experiments (in South America and South Africa). Comparing the xylenes to toluene and benzene indicate that combustion, but not fuel evaporation, is the major common source of the xylenes in areas dominated by automotive emissions. Although a wide range of combustion types and combustion efficiencies were encountered throughout all the locations investigated, xylenes and ethylbenzene ratios remained persistent. We discuss the implications of the constancies in the xylenes and ethylbenzene ratios on atmospheric chemistry.

Rapid analysis of six phthalate esters in wine by ultrasound-vortex-assisted dispersive liquid-liquid micro-extraction coupled with gas chromatography-flame ionization detector or gas chromatography-ion trap mass spectrometry.

An Ultrasound-Vortex-Assisted Dispersive Liquid-Liquid Micro-Extraction (USVADLLME) procedure coupled with Gas Chromatography-Flame Ionization Detector (GC-FID) or Gas Chromatography-Ion Trap Mass Spectrometry (GC-IT/MS) is proposed for rapid analysis of six phthalate esters in hydroalcoholic beverages (alcohol by volume, alc vol(-1), ≤40%). Under optimal conditions, the enrichment factor of the six analytes ranges from 220- to 300-fold and the recovery from 85% to 100.5%. The limit of detection (LOD) and limit of quantification (LOQ) are ≥0.022 μg L(-1) and ≥0.075 μg L(-1), respectively. Intra-day and inter-day precisions expressed as relative standard deviation (RSD), are ≤8.2% and ≤7.0%, respectively. The whole proposed methodology has demonstrated to be simple, reproducible and sensible for the determination of trace phthalate esters in red and white wine samples.

Chemical, dimensional and morphological ultrafine particle characterization from a Waste-to-Energy plant

Waste combustion processes are responsible of particles and gaseous emissions. Referring to the particle emission, in the last years specific attention was paid to ultrafine particles (UFPs, diameter less than 0.1 μm), mainly emitted by combustion processes. In fact, recent findings of toxicological and epidemiological studies indicate that fine and ultrafine particles could represent a risk for health and environment. Therefore, it is necessary to quantify particle emissions from incinerators also to perform an exposure assessment for the human populations living in their surrounding areas. To these purposes, in the present work an experimental campaign aimed to monitor UFPs was carried out at the incineration plant in San Vittore del Lazio (Italy). Particle size distributions and total concentrations were measured both at the stack and before the fabric filter inlet in order to evaluate the removal efficiency of the filter in terms of UFPs. A chemical characterization of UFPs in terms of heavy metal concentration was performed through a nuclear method, i.e., Instrumental Neutron Activation Analysis (INAA), as well as a mineralogical investigation was carried out through a Transmission Electron Microscope (TEM) equipped with an Energy Dispersive Spectrometer (EDS) in order to evaluate shape, crystalline state and mineral compound of sampled particles. Maximum values of 2.7 × 10(7) part. cm(-3) and 2.0 × 10(3) part. cm(-3) were found, respectively, for number concentration before and after the fabric filter showing a very high efficiency in particle removing by the fabric filter. With regard to heavy metal concentrations, the elements with higher boiling temperature present higher concentrations at lower diameters showing a not complete evaporation in the combustion section and the consequent condensation of semi-volatile compounds on solid nuclei. In terms of mineralogical and morphological analysis, the most abundant compounds found in samples collected before the fabric filter are Na-K-Pb oxides followed by phyllosilicates, otherwise, different oxides of comparable abundance were detected in the samples collected at the stack.

Determination of organophosphorus pesticide residues in human tissues by capillary gas chromatography–negative chemical ionization mass spectrometry analysis

We describe an analytical method that allows the determination of organophosphorus pesticides (OPs) in different human tissues. It involves an extraction procedure with ethanol-ethyl acetate, followed by gel permeation chromatography clean-up step and analysis by capillary gas chromatography-negative chemical ionization mass spectrometry in the selected ion monitoring mode. The method was tested for 37 OPs and the recoveries obtained vary between 60 and 106% with standard deviations ranging between +/-2 and +/-10. These values are independent of the analyzed tissue. Peak area repeatability as RSD for some OPs was < or =4.8% while a good linear relationship in the range 1.0-500 pg microl(-1) with r(2)> or =0.9878 was obtained. The limit of detection for the 37 OPs falls between 0.01 and 0.09 ng g(-1) with an RSD< or =9.5%. The analytical set up in this paper has been used to analyze different samples of human tissues (liver, healthy kidney, cancer kidney and adipose tissue) of 24 patients. The number of the identified OPs in the tissue samples is different (max. 20) according to the sample while their concentration ranges between the limit of detection and 28.0 ng g(-1). The highest concentrations have been determined in liver samples without any pathology (0.4-28.0 ng g(-1)) while the lowest concentrations have been determined in healthy kidney samples (0.01-1.50 ng g(-1)). In the cancer kidney samples OP concentrations vary between 0.03 and 4.6 ng g(-1): these concentrations are more elevated than those determined in healthy kidney samples. The comparison between the concentration of OPs determined in the healthy part, when possible, and those determined in the cancer part of the same kidney sample are very interesting: in fact, in the latter the OP concentration is generally 1-2-times higher than that in the former, an index of lower enzymatic activity in the cancer tissue.

Simultaneous determination of cysteine, cystine and 18 other amino acids in various matrices by high-performance liquid chromatography.

An extraction protocol and a reversed-phase high-performance liquid chromatographic method for the simultaneous determination of cysteine, cystine and 18 other amino acids in biological and vegetable samples are described. Among the different methods proposed for amino acid determination, phenylisothiocyanate was used as the reagent for derivatization. Chromatograms obtained in the analysis of standard solutions and actual samples are reported, together with regression equation, correlation coefficient (> 0.999 for all), limit of detection and recoveries (between 86 and 102% for all the examined matrices) for each amino acid. Practical protocol and method applications in normal patients and patients affected by different pathologies, and in algal products are discussed.

Study of XAD-2 adsorbent for the enrichment of trace levels of phthalate esters in hydroalcoholic food beverages and analysis by gas chromatography coupled with flame ionization and ion-trap mass spectrometry detectors

An analytical method based on solid-phase extraction (SPE) with Amberlite XAD-2 adsorbent used as stationary phase for determining phthalate esters (PAEs) in hydroalcoholic food beverages by GC-FID (and peak confirmation by GC-IT/MS) has been set up. The XAD-2 resin shows excellent properties for determining PAEs in solutions at very large alcoholic range (10-40% v/v): 500mL of hydroalcoholic solution spiked with a PAE mixture solution (20pgμL(-1) of each PAE) and containing 25gL(-1) of NaCl are passed onto a cartridge containing 500mg XAD-2 adsorbent and re-extracted for GC analysis. The effects of NaCl concentration (0, 12, 25 and 50gL(-1)) and different solvents (CS2, toluene, acetone, n-hexane, ethyl acetate) are extensively studied as well the PAE recoveries both in hydroalcoholic aqueous solutions (ranging between 94% and 103% with a Relative Standard Deviation, RSD, below 8.3) and spiked (5, 10 and 25pgμL(-1) of each PAE) real samples (between 90% and 106% with a RSD below 9.9). The correlation coefficients (R(2)) of each PAE vary between 0.9830 and 0.9950 and they are calculated in the linear range 5-100pgμL(-1). The limits of detection (LOD) in GC-FID vary between 1.21 and 2.51pgμL(-1) (RSD⩽11.1) whereas the Limits of Quantification (LOQ) range between 2.42 and 5.03pgμL(-1) (RSD⩽8.9) whereas the infra-day and inter-day repeatabilities calculated as RSD for hydroalcoholic solutions, are between 6.5% and 13.7%.

Ultrasound-vortex-assisted dispersive liquid–liquid microextraction coupled with gas chromatography with a nitrogen–phosphorus detector for simultaneous and rapid determination of organophosphorus pesticides and triazines in wine

A low solvent consumption method for the sensitive determination of organophosphorus (OP) and triazine (TR) pesticides in wine samples is studied. The pesticides were extracted by ultrasound vortex assisted dispersive liquid–liquid microextraction (USVADLLME): 10 mL of sample, 1 mL of NaH2PO4 1 M, 10 μL tolidin in ethanol (internal standard) and 250 μL of C2H4Cl2 (extraction solvent) were vortexed for 30 s (any dispersive solvent was used) and the solution was kept in an ultrasound bath: the extraction was performed at 40 kHz of ultrasound frequency and 110 W for 10 min at room temperature. The determination was performed by means of gas chromatography equipped with nitrogen–phosphorus detector (GC-NPD). The enrichment factors of the analytes ranged from 210 to 232 fold and the recovery ranged from 92.0% to 103.4% (with a Relative Standard Deviation, RSD, below 7.5%). After centrifugation, the bottom phase of the chlorinated solvent was separated from the liquid hydro-alcoholic matrix, dried with anhydrous Na2SO4 and injected into the GC-NPD system. The efficiency of the liquid-phase micro-extraction process was slightly affected by the characteristics of wine samples, therefore the analytical characteristics of the method were evaluated in the linear range 0.01–10 ng mL−1. The correlation coefficients (R2) of each pesticide are above 0.963. The Limits of Detection (LOD) in GC-NPD vary between 0.007 ng mL−1 and 0.07 ng mL−1 (RSD ≤ 9.0) whereas the Limits of Quantification (LOQ) range between 0.024 ng mL−1 and 0.225 ng mL−1 (RSD ≤ 6.9); the intra-day and inter-day repeatabilities, calculated as RSD in the real matrix, are below 6.7% and 8.8%, respectively. Particular attention was devoted to comparing this methodology with other similar analytical methodologies: LODs and RSDs were studied and commented upon. It should be underlined that the good sensibility and high versatility of this methodology allow investigation of organophosphorus and triazine pesticides. At the end, the applicability of the method was demonstrated using commercial wine samples.

Dimensional and chemical characterization of particles at a downwind receptor site of a waste-to-energy plant

In the last years numerous epidemiological studies were carried out to evaluate the effects of particulate matter on human health. In industrialized areas, anthropogenic activities highly contribute to the fine and ultrafine particle concentrations. Then, it is important to characterize the evolution of particle size distribution and chemical composition near these emission points. Waste incineration represents a favorable technique for reducing the waste volume. However, in the past, municipal waste incinerators (MWIs) had a bad reputation due to the emission of toxic combustion byproducts. Consequently, the risk perception of the people living near MWIs is very high even if in Western countries waste incineration has nowadays to be considered a relatively clean process from a technical point of view. The study here presented has an exemplary meaning for developing appropriate management and control strategies for air quality in the surrounding of MWIs and to perform exposure assessment for populations involved. Environment particles were continuously measured through a SMPS/APS system over 12 months. The monitoring site represents a downwind receptor of a typical MWI. Furthermore, elements and organic fractions were measured by means of the Instrumental Neutron Activation Analysis and using dichotomous and high volume samplers. Annual mean values of 8.6 x 10(3)+/-3.7 x 10(2)part.cm(-3) and 31.1+/-9.0 microg m(-3) were found for number and mass concentration, typical of a rural site. Most of the elements can be attributed to long-range transport from other natural and/or anthropogenic sources. Finally, the Polycyclic Aromatic Hydrocarbons present low concentrations with a mean value of 24.6 ng m(-3).

Characterization and distribution of mineral content in fine and coarse airborne particle fractions by neutron activation analysis

Nowadays, much attention is devoted to the study of toxic elements at trace and sub-trace levels in the investigation of particulate matter composition, especially in PM10 and PM2.5. Furthermore, it should be considered that the behavior knowledge is an other important task for understanding such species. Finally, the determination of particular elements with a few data in literature can assume relevant importance in industrial processes (Pd, Rh, Ir, etc. for catalytic pot, Sm, Ce, Eu, etc. for optical fibers and electronic process). In this article, we apply a nuclear technique, i.e. Instrumental Neutron Activation Analysis, for the study of metal composition in fine and coarse fractions. This nuclear technique allows the determination of about 25 elements: for some of them, this is the first determination in the ambient air of Rome. The investigation was performed in a reserved area in downtown Rome during a 15-day intensive campaign. The sampled filters were irradiated at the nuclear reactor Triga Mark II (ENEA-Casaccia Laboratories) at neutron flux of 2.6 × 1012 n cm−2 s−1 for 32.55 h. The measurements of the γ-ray allow the qualitative and quantitative analysis. The element levels in fine and coarse fractions will be shown with the correlations among some elements being more interesting in the toxicological field: basically, the concentrations are very low. * Presented at the 10th EuCheMS-DCE International Conference on Chemistry and the Environment in Rimini on 4–7 September 2005.

Extraction and GC-MS analysis of phthalate esters in food matrices: a review

According to the Scopus database, using “phthalate” and “GC” as keywords, 758 papers have been found between 1990 and 2014, showing strong and increasing interest in this class of compounds from the scientific community. This review focuses attention on phthalate ester (PAE) extraction procedures, followed by GC-MS analysis, applied to food matrices and developed during the last 15 years (from 2000). In this area, 120 papers have been published, divided according to different sample preparation/extraction methods: liquid–liquid extraction (LLE), solid-phase (micro) extraction (SP(M)E), dispersive liquid–liquid (micro) extraction (DLL(M)E), headspace solid-phase micro-extraction (HS-SPME), microwave extraction, supercritical fluid extraction, ultrasonication extraction, thermal desorption extraction and Soxhlet extraction. Finally, for in-depth information, two important issues, phthalate toxicology and risk assessment and the blank problem in analytical determinations, are discussed.