58 research outputs found
Benzothiazoles as Molecular Markers for Automobile Tire Derived Inputs: Occurrence and Phase Distribution in Highway Runoff and Road Dust
Over the past several decades, discharges of both wastewater and stormwater have been identified as one of the major causes of the deterioration observed in receiving waters (Lamprea and Ruban, 2011). The major sources are vehicle emissions, motor oil, tyre and brake wear, and road particles in urban environments. During rainfall events contaminants are washed into the stormwater system and then discharged. The Italian legislation (Legislative Decree no. 152 of 11 May 1999) provides a complete program for the protection of water bodies from pollution. The decree implements the community directive 91/271/EEC concerning the treatment of urban wastewater, that constitutes the reference standard for the EU member states. The Italian law focuses on the quality of the receiving water body with several monitoring activities for determining the environmental damage. Despite these steps forward, several pollutants are not determined and their impact and fate in the environment are unknown. Furthermore, a comprehensive determination of contaminants of emerging concern (CECs) is crucial to understand the distribution of target compounds in dissolved phase and suspended particulate matter (Feltracco et al., 2022). The accumulation of road dust itself also serves as a notable pollutant source because it can be transported by runoff, and the associated pollutants could adversely affect the water ecosystem. Among the hazardous pollutants in dissolved phase, suspended particulate matter and road dust particles originating from tires, rubbers, and microplastics are often observed (Rosso et al., 2022), together with benzothiazoles. A total of eight benzothiazoles were determined in highway stormwater runoff and road collected from February to April 2022 near Venice (Casale sul Sile, Veneto Region, Italy). A full validated method is presented, by using an ultra-high pressure liquid chromatography coupled to a triple quadrupole mass spectrometer. The target compounds were determined in both dissolved phase and suspended particulate matter of runoff. The road dust samples were divided in seven fractions depending on particles diameters to evaluate the fraction partitioning. The results underline that SO₃H-BTH was the most concentrated benzothiazole derivate in all the analysed substrates, suggesting the presence of tires debris as main source because it is used in the vulcanization processes. The three major compounds in the dissolved phase were inversely correlated with precipitation amount and positively correlated with the number of days after last rain event, while no correlation were found with suspended particulate matter. The road dust samples indicated a clear trend of the majority of benzothiazoles to distribute in the finest fraction (<63 µm). The distribution of 2-SCNMeS-BTH was opposite to the other benzothiazoles, suggesting a different source and environmental behaviour
Assessing glyphosate in water, marine particulate matter, and sediments in the Lagoon of Venice
Lagoon water, suspended particulate matter, and sediment samples from seven sites at Lagoon of Venice were collected from 2019 to 2021 in order to study the presence of the herbicide glyphosate (N-(phosphonomethyl)glycine), among the most widely used agricultural chemicals worldwide, but its occurrence in lagoon water environment has not been deeply investigated. The sites were selected considering a supposed diversity of inputs and of pollution levels. An analytical method based on ion chromatography coupled with tandem mass spectrometry was optimized and validated for lagoon water, marine particulate matter, and sediment samples. Maximum concentrations of glyphosate were 260 and 7 ng L−1 for lagoon water and suspended particulate matter, respectively, and 15 ng g−1 for sediment, with some spatial and temporal fluctuations. Our results demonstrate that glyphosate content in the Venice Lagoon mainly depends on external forcing from river inlets and agricultural lagoon activities
Studio della composizione chimica nelle diverse classi dimensionali dell’aerosol artico idrosolubile
Lo studio della composizione chimica dell’aerosol atmosferico idrosolubile è di fondamentale importanza ambientale dato che i composti idrosolubili possono influenzare l’igroscopicità delle particelle di aerosol e agire come nuclei di condensazione delle nubi.
In questo studio sono state analizzate le specie anioniche e cationiche, gli acidi carbossilici, i mono- e di-saccaridi, gli alcool-zuccheri ed anidro-zuccheri, i composti fenolici, gli L e D- amminoacidi (FAA e CAA) e i composti di foto-ossidazione dell’α-pinene (acido cis-pinonico ed acido pinico). Le analisi sono state effettuate su campioni di aerosol atmosferico raccolti da aprile a giugno 2015 a Ny Ålesund (78°55'07''N, 11°53'30''E; Isole Svalbard, Norvegia). L’aerosol è stato campionato con un impattore a cascata ad alto volume (TE-6070, PM10 high volume air sampler) che ha permesso di suddividere il particolato atmosferico in sei frazioni dimensionali: 10.0–7.2, 7.2–3.0, 3.0–1.5, 1.5–0.95, 0.95-0.49, <0.49 μm.
La quantificazione dei composti di foto-ossidazione dell’α-pinene, di zuccheri ed alcool- zuccheri, degli amminoacidi combinati e degli enantiomeri L e D in ambienti polari è scarsamente studiata e sono stati condotti solamente alcuni studi preliminari sull'andamento degli amminoacidi in ambienti artici e sull’andamento di zuccheri ed alcool-zuccheri in aree sub-artiche norvegesi e finlandesi. I traccianti da combustione da biomassa, in particolare l’anidro-zucchero levoglucosan e i composti fenolici, risultano invece già abbondantemente studiati in queste aree remote.
L’obiettivo è di valutare i processi di trasporto intercontinentali confrontando la composizione chimica dell’aerosol nelle diverse frazioni dimensionali. Lo studio di questi composti ha permesso inoltre di investigare i processi di formazione e di trasformazione dell’aerosol di origine biogenica e da combustioni da biomassa
Distribuzione dimensionale di ioni organici e inorganici dell’aerosol Artico: sorgenti e trasporto in una serie temporale di un anno
Con questo studio è stata determinata la distribuzione dimensionale e la concentrazione di specie ioniche e composti di foto-ossidazione dell’α-pinene nell’aerosol Artico con l’obiettivo di investigare sorgenti, processi chimici in atmosfera e di trasporto considerando un anno intero di campionamento. L’aerosol atmosferico è stato prelevato dal 26 febbraio 2018 al 26 febbraio 2019 presso l’osservatorio di Gruvebadet, Ny Ålesund (78°55′03″N, 11°53′39″E, 50 m a.s.l.) con una risoluzione da 6 a 10 giorni. I composti analizzati comprendono i principali ioni inorganici (Cl-, Br-, I-, NO−, SO42−, K+, Mg2+,Na+, NH4+, Ca2+), acidi organici (acido metansolfonico e acidi carbossilici C2–C7) e composti di foto-ossidazione dell’α-pinene (acido pinico e acido cis-pinonico). A causa della vicinanza dal fiordo (Kongsfjorden) in cui si trova il sito del campionamento, l’aerosol campionato è caratterizzato principalmente da particelle derivanti da spray marino (Na+, Cl- e SO42−). Queste specie rappresentano il 74% della somma totale delle specie ioniche studiate. Di grande importanza risulta essere il non sea salt-SO42− che, rispetto al solfato totale, è circa l’85% ed è presente a causa di trasporti a lungo raggio da aree antropizzate, specialmente dall’Eurasia. Composti a concentrazione molto più bassa come acidi carbossilici e composti di foto-ossidazione dell’α-pinene hanno rilevante interesse ambientale per lo studio delle condizioni atmosferiche e dei trasporti a lungo raggio, soprattutto durante l’inverno polare
Fast Liquid Chromatography Coupled with Tandem Mass Spectrometry for the Analysis of Vanillic and Syringic Acids in Ice Cores
The development of new analytical systems and the improvement of the existing ones to obtain high-resolution measurements of chemical markers in samples from ice cores, is one of the main challenges the paleoclimatic scientific community is facing. Different chemical species can be used as markers for tracking emission sources or specific environmental processes. Although some markers, such as methane sulfonic acid (a proxy of marine productivity), are commonly used, there is a lack of data on other organic tracers in ice cores, making their continuous analysis analytically challenging. Here, we present an innovative combination of fast liquid chromatography coupled with tandem mass spectrometry (FLC-MS/MS) to continuously determine organic markers in ice cores. After specific optimization, this approach was applied to the quantification of vanillic and syringic acids, two specific markers for biomass burning. Using the validated method, detection limits of 3.6 and 4.6 pg mL–1 for vanillic and syringic acids, respectively, were achieved. Thanks to the coupling of FLC-MS/MS with the continuous flow analytical system, we obtained one measurement every 30 s, which corresponds to a sampling resolution of a sample every 1.5 cm with a melting rate of 3.0 cm min–1. To check the robustness of the method, we analyzed two parallel sticks of an alpine ice core over more than 5 h. Vanillic acid was found with concentrations in the range of picograms per milliliter, suggesting the combustion of coniferous trees, which are found throughout the Italian Alps.publishedVersio
Caratterizzazione dimensionale dei composti solubili in acqua nella frazione ultrafine, fine e grossolana dell’aerosol urbano
Lo scopo di questo lavoro consiste nello studio della composizione chimica della frazione idrosolubile dell’aerosol atmosferico in funzione del diametro delle particelle in un’area urbana. La composizione chimica delle particelle in funzione della loro dimensione influisce notevolmente sul ruolo ambientale, tossicologico e legislativo dell’aerosol atmosferico. Per la prima volta, questo studio può fornire un utile strumento analitico ambientale per indagare la composizione della frazione ultrafine dell’aerosol urbano.
Nel sito urbano di Mestre-Venezia sono stati raccolti 14 campioni di aerosol in un periodo compreso tra marzo e maggio 2016, utilizzando un impattore MOUDI II che ha permesso di suddividere l’aerosol in 12 frazioni dimensionali (>18 μm; 18-10 μm; 10-5.6 μm; 5.6-3.2 μm; 3.2- 1.8 μm; 1.8-1 μm; 1-0.56 μm; 0.56 -0.32 μm; 0.32-0.18 μm; 0.18-0.1 μm; 0.1-0.056 μm; <0.056 μm). Ciascuno dei 168 supporti campionati è stato pesato in un camera bianca ISO 7 ed estratto in acqua ultrapura con ultrasuoni. L’estratto acquoso è stato analizzato mediante IC-MS per la determinazione di specie ioniche (ioni maggiori, acido metansolfonico, acidi carbossilici) e zuccheri (alcol zuccheri, anidrozuccheri, mono- e disaccaridi) e mediante HPLC-MS/MS per la determinazione di L- e D- amminoacidi, composti fenolici, composti di degradazione dell’α-pinene.
I risultati ottenuti evidenziano che le specie idrosolubili analizzate rappresentano mediamente tra il 14% ( 1 μm) sono il sodio, il calcio e il nitrato mentre la frazione fine (<1 μm) è caratterizzata da alte concentrazioni di solfato, ammonio e acidi carbossilici. Nitrato e solfato sono invece le specie caratteristiche della frazione nano (<100 nm). Per ciascuna classe di composti studiata è stata indagata la sorgente di emissione e la relativa distribuzione in funzione del diametro delle particelle. Ad esempio, lo studio di L e D-amminoacidi ha dimostrato che l’amminoacido a più alta concentrazione è la glicina, segue L-prolina, L-arginina, acido L-glutammico e D-alanina. Le alte concentrazioni della glicina, principalmente presente nella frazione fine (180 nm - 1 μm), sono legate alla stabilità del composto, mentre la L-prolina che deriva da spore si distribuisce maggiormente nella frazione grossolana.
Considerato l’elevato numero di specie analizzate, è stato applicato un approccio chemiometrico che ha permesso di individuare quattro specifiche sorgenti di emissione: emissione marina primaria, emissione marina di specie secondarie, combustione di biomassa e una sorgente mista. Mentre i composti che caratterizzano la sorgente marina primaria si distribuiscono nella frazione grossolana dell’aerosol (>1 μm), i composti secondari di origine marina si distribuiscono sulle particelle più fini (<1 μm), come anche i composti specifici della combustione di biomassa
Characterization of free L- and D-amino acids in size-segregated background aerosols over the Ross Sea, Antarctica
The study of airborne chemical markers is crucial for identifying sources of aerosols, and their atmospheric processes of transport and transformation. The investigation of free amino acids and their differentiation between the L-and D- en-antiomers are even more important to understand their sources and atmospheric fate. Aerosol samples were collected with a high-volume sampler with cascade impactor at Mario Zucchelli Station (MZS) on the coast of the Ross Sea (Antarctica) for two summer campaigns (2018/19 and 2019/20). The total mean concentration of free amino acids in PM10 was 4 +/- 2 pmol m-3 for both campaigns and most of free amino acids were distributed in fine particles. The coarse mode of airborne D-Alanine and dimethylsufoniopropionate in seawater showed a similar trend during both Antarctic campaigns. Thus, the study of D/L Ala ratio in fine, coarse and PM10 fractions indicated the microlayer as the local source. This paper demonstrated that free amino acids follow the trend of DMS and MSA release occurred in the Ross Sea, confirming their applicability as markers for phytoplankton bloom also in paleoclimatic studies
An upgraded CFA - FLC - MS/MS system for the semi-continuous detection of levoglucosan in ice cores
A new Continuous Flow Analysis (CFA) system coupled with Fast Liquid Chromatography – tandem Mass Spectrometry (FLC-MS/MS) has been recently developed for determining organic markers in ice cores. In this work we present an upgrade of this innovative technique, optimized for the detection of levoglucosan in ice cores, a crucial tracer for reconstructing past fires. The upgrade involved a specific optimization of the chromatographic and mass spectrometric parameters, allowing for a higher sampling resolution (down to 1 cm) and the simultaneous collection of discrete samples, for off-line analysis of water stable isotopes and additional chemical markers. The robustness and repeatability of the method has been tested by the analysis of multiple sticks of ice cut from the same shallow alpine ice core, and running the system for several hours on different days. The results show similar and comparable trends between the ice sticks. With this upgraded system, a higher sensitivity and a lower limit of detection (LOD) was achieved compared to discrete analysis of alpine samples for levoglucosan measurements. The new LOD was as low as 66 ng L−1, a net improvement over the previous LOD of 600 ng L−1
Preservation of chemical and isotopic signatures within the Weißseespitze millennial old ice cap (Eastern Alps), despite the ongoing ice loss
Alpine ice core research has long focused on a few suitable drilling sites at high elevation in the Western European Alps, assuming that the counterparts at lower elevation in the eastern sector are unsuitable for paleoenvironmental studies, due to the presence of melting and temperate basal conditions. However, it has been demonstrated that even in the Eastern Alpine range, below 4,000 m a.s.l., cold ice frozen to bedrock can exist. In fact, millennial-old ice has been found at some locations, such as at the Weißseespitze (WSS) summit ice cap (Ӧtztal Alps, 3,499 m a.s.l.), where about 6 kyrs appear locked into 10 m of ice. In this work, we present a full profile of the stable water isotopes (δ18O, δ2H), major ions (Na+, K+, Mg2+, Ca2+, NH4+, Cl−, NO3−, SO42−), levoglucosan, and microcharcoal for two parallel ice cores drilled at the Weißseespitze cap. We find that, despite the ongoing ice loss, the chemical and isotopic signatures appear preserved, and may potentially offer an untapped climatic record. This is especially noteworthy considering that chemical signals of other archives at similar locations have been partially or full corrupted by meltwater (i.e., Silvretta glacier, Grand Combin glacier, Ortles glacier). In addition, the impurity concentration near the surface shows no signs of anthropogenic contamination at WSS, which constrains the age at the surface to fall within the pre-industrial age
- …