High-altitude glacier archives lost due to climate change-related melting.

Global warming has caused widespread surface lowering of mountain glaciers. By comparing two firn cores collected in 2018 and 2020 from Corbassière glacier in Switzerland, we demonstrate how vulnerable these precious archives of past environmental conditions have become. Within two years, the soluble impurity records were destroyed by melting. The glacier is now irrevocably lost as an archive for reconstructing major atmospheric aerosol components.

Rapa Nui (Easter Island) Rano Raraku crater lake basin: Geochemical characterization and implications for the Ahu-Moai Period.

Rano Raraku, the crater lake constrained by basaltic tuff that served as the primary quarry used to construct the moai statues on Rapa Nui (Easter Island), has experienced fluctuations in lake level over the past centuries. As one of the only freshwater sources on the island, understanding the present and past geochemical characteristics of the lake water is critical to understand if the lake could have been a viable freshwater source for Rapa Nui. At the time of sampling in September 2017, the maximum lake depth was ~1 m. The lake level has substantially declined in the subsequent years, with the lake drying almost completely in January 2018. The lake is currently characterized by highly anoxic conditions, with a predominance of ammonium ions on nitrates, a high concentration of organic carbon in the water-sediment interface and reducing conditions of the lake, as evidenced by Mn/Fe and Cr/V ratios. Our estimates of past salinity inferred from the chloride mass balance indicates that it was unlikely that Rano Raraku provided a viable freshwater source for early Rapa Nui people. The installation of an outlet pipe around 1950 that was active until the late 1970s, as well as grazing of horses on the lake margins appear to have significantly impacted the geochemical conditions of Rano Raraku sediments and lake water in recent decades. Such impacts are distinct from natural environmental changes and highlight the need to consider the sensitivity of the lake geochemistry to human activities.

Evidence of small microplastics (<100 µm) ingestion by Pacific oysters (Crassostrea gigas): A novel method of extraction, purification, and analysis using Micro-FTIR.

Microplastics (MPs) are present in fresh, brackish, or marine waters. Micro- and macroinvertebrates can mistake MPs or small microplastics (SMPs, <100 µm) to be food particles and easily ingest them according to the size of their mouthparts. SMPs may then block the passage of food through the intestinal tract (i.e. hepatopancreas), accumulate within the organism, and enter the food web. Pacific oysters (Crassostrea gigas) are allochthonous filter-feeding bivalve mollusks, which have been introduced in coastal seas around the world in both natural banks and farms. Considering their economic and ecological value, these bivalves have been chosen as a model to study the ingestion of SMPs. A novel method for the extraction and purification of SMPs in bivalves was developed. Quantification and simultaneous polymer identification of SMPs using Micro-FTIR (Fourier Transform Infrared Spectroscopy) were performed, with a limit of detection for the particle size of 5 µm.

Lake sediment fecal and biomass burning biomarkers provide direct evidence for prehistoric human-lit fires in New Zealand.

Deforestation associated with the initial settlement of New Zealand is a dramatic example of how humans can alter landscapes through fire. However, evidence linking early human presence and land-cover change is inferential in most continental sites. We employed a multi-proxy approach to reconstruct anthropogenic land use in New Zealand's South Island over the last millennium using fecal and plant sterols as indicators of human activity and monosaccharide anhydrides, polycyclic aromatic hydrocarbons, charcoal and pollen as tracers of fire and vegetation change in lake-sediment cores. Our data provide a direct record of local human presence in Lake Kirkpatrick and Lake Diamond watersheds at the time of deforestation and a new and stronger case of human agency linked with forest clearance. The first detection of human presence matches charcoal and biomarker evidence for initial burning at c. AD 1350. Sterols decreased shortly after to values suggesting the sporadic presence of people and then rose to unprecedented levels after the European settlement. Our results confirm that initial human arrival in New Zealand was associated with brief and intense burning activities. Testing our approach in a context of well-established fire history provides a new tool for understanding cause-effect relationships in more complex continental reconstructions.

Greenland records of aerosol source and atmospheric lifetime changes from the Eemian to the Holocene.

The Northern Hemisphere experienced dramatic changes during the last glacial, featuring vast ice sheets and abrupt climate events, while high northern latitudes during the last interglacial (Eemian) were warmer than today. Here we use high-resolution aerosol records from the Greenland NEEM ice core to reconstruct the environmental alterations in aerosol source regions accompanying these changes. Separating source and transport effects, we find strongly reduced terrestrial biogenic emissions during glacial times reflecting net loss of vegetated area in North America. Rapid climate changes during the glacial have little effect on terrestrial biogenic aerosol emissions. A strong increase in terrestrial dust emissions during the coldest intervals indicates higher aridity and dust storm activity in East Asian deserts. Glacial sea salt aerosol emissions in the North Atlantic region increase only moderately (50%), likely due to sea ice expansion. Lower aerosol concentrations in Eemian ice compared to the Holocene are mainly due to shortened atmospheric residence time, while emissions changed little.

Prominent features in isotopic, chemical and dust stratigraphies from coastal East Antarctic ice sheet (Eastern Wilkes Land).

In this work we present the isotopic, chemical and dust stratigraphies of two snow pits sampled in 2013/14 at GV7 (coastal East Antarctica: 70°41' S - 158°51' E, 1950 m a.s.l.). A large number of chemical species are measured aiming to study their potentiality as environmental changes markers. Seasonal cluster backward trajectories analysis was performed and compared with chemical marker stratigraphies. Sea spray aerosol is delivered to the sampling site together with snow precipitation especially in autumn-winter by air masses arising from Western Pacific Ocean sector. Dust show maximum concentration in spring when the air masses arising from Ross Sea sector mobilize mineral dust from ice-free areas of the Transantarctic mountains. The clear seasonal pattern of sulfur oxidized compounds allows the dating of the snow-pit and the calculation of the mean accumulation rate, which is 242 ± 71 mm w.e. for the period 2008-2013. Methanesulfonic acid and NO3- do not show any concentration decreasing trend as depth increases, also considering a 12 m firn core record. Therefore these two compounds are not affected by post-depositional processes at this site and can be considered reliable markers for past environmental changes reconstruction. The rBC snow-pit record shows the highest values in summer 2012 likely related to large biomass burning even occurred in Australia in this summer. The undisturbed accumulation rate for this site is demonstrated by the agreement between the chemical stratigraphies and the annual accumulation rate of the two snow-pits analysed in Italian and Korean laboratories.

Seasonal accumulation of persistent organic pollutants on a high altitude glacier in the Eastern Alps.

The seasonal accumulations of perfluorinated substances (PFAS), polybrominated diphenyl ethers (PBDE) and polycyclic aromatic hydrocarbons (PAH) were measured in a 10 m shallow firn core from a high altitude glacier at Mt. Ortles (Italy, 3830 m above sea level) in South Tyrol in the Italian Eastern Alps. The most abundant persistent organic pollutants of each group were perfluorobutanoic acid (PFBA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) (for PFASs); BDE 47, BDE 99, BDE 209 (for PBDEs) and phenanthrene (PHE), fluoranthene (FLA) and pyrene (PYR) (for PAHs). All compounds show different extents of seasonality, with higher accumulation during summer time compared to winter. This seasonal difference mainly reflects meteorological conditions with a low and stable atmospheric boundary layer in winter and strong convective activity in summer, transformation processes during the transport of chemicals and/or post-depositional alterations. Change in the composition of the water-soluble PFCAs demonstrates the influence of meltwater percolation through the firn layers.

Mass distributions and morphological and chemical characterization of urban aerosols in the continental Balkan area (Belgrade).

This work presents characteristics of atmospheric aerosols of urban central Balkans area, using a size-segregated aerosol sampling method, calculation of mass distributions, SEM/EDX characterization, and ICP/MS analysis. Three types of mass distributions were observed: distribution with a pronounced domination of coarse mode, bimodal distribution, and distribution with minimum at 1 µm describing the urban aerosol. SEM/EDX analyses have shown morphological difference and variation in the content of elements in samples. EDX spectra demonstrate that particles generally contain the following elements: Al, Ca, K, Fe, Mg, Ni, K, Si, S. Additionally, the presence of As, Br, Sn, and Zn found in air masses from southeast segment points out the anthropogenic activities most probably from mining activities in southeastern part of Serbia. The ratio Al/Si equivalent to the ratio of desert dust was associated with air masses coming from southeastern and southwestern segments, pointing to influences from North Africa and Middle East desert areas whereas the Al/Si ratio in other samples is significantly lower. In several samples, we found high values of aluminum in the nucleation mode. Samples with low share of crustal elements in the coarse mode are collected when Mediterranean air masses prevailed, while high share in the coarse mode was associated with continental air masses that could be one of the approaches for identification of the aerosol origin. Graphical abstract ᅟ.

Domoic acid at trace levels in lagoon waters: assessment of a method using internal standard quantification.

Domoic acid (DA) is a neurotoxin produced by different algae, including pennate diatoms, principally from the genus Pseudo-nitzschia, and it is the main cause of amnesic shellfish poisoning. Determination of this toxin in seawater samples is fundamental to define the real contamination risks for aquatic species. We have developed two very sensitive instrumental methods using hydrophilic interaction liquid chromatography coupled using tandem mass spectrometry in positive and negative polarity modes. Instrumental detection limits were 9 pg mL(-1) for positive and 19 pg mL(-1) for negative ionisation. A procedural method based on solid-phase extraction for the determination of dissolved DA present in seawater has been developed, and an extraction procedure was employed for the determination of the toxin in the particulate fraction. DA quantification was performed using the internal standard method to account for signals fluctuations and random errors during sample treatment. To our knowledge, this is the first study to use this quantification method for DA determination. Trueness, extraction yield, matrix effects, repeatability and procedural detection limits were evaluated during method validation. Procedural detection limits of 0.3 pg mL(-1) (positive mode) and 0.6 pg mL(-1) (negative mode) were found for the dissolved fraction, and absolute limits of 0.4 pg (positive mode) and 6.0 pg (negative mode) for particulate samples were obtained. The most sensitive method in positive mode was applied to define DA occurrence in the Venice Lagoon. Trace concentrations of domoic acid ranging from 1.5 to 16.2 pg mL(-1) were found for the first time in the Venetian environment.

Synchronous change of atmospheric CO2 and Antarctic temperature during the last deglacial warming.

Understanding the role of atmospheric CO2 during past climate changes requires clear knowledge of how it varies in time relative to temperature. Antarctic ice cores preserve highly resolved records of atmospheric CO2 and Antarctic temperature for the past 800,000 years. Here we propose a revised relative age scale for the concentration of atmospheric CO2 and Antarctic temperature for the last deglacial warming, using data from five Antarctic ice cores. We infer the phasing between CO2 concentration and Antarctic temperature at four times when their trends change abruptly. We find no significant asynchrony between them, indicating that Antarctic temperature did not begin to rise hundreds of years before the concentration of atmospheric CO2, as has been suggested by earlier studies.

Continuous flow analysis method for determination of soluble iron and aluminium in ice cores.

Iron and aluminium are the two most abundant metals on the Earth's crust, but they display quite different biogeochemical properties. While iron is essential to many biological processes, aluminium has not been found to have any biological function at all. In environmental studies, iron has been studied in detail for its limiting role in the bioproductivity of high nutrient, low carbon oceanic zones, while aluminium is routinely used as a reference of crustal contributions to atmospheric deposition archives including peat bogs, lacustrine and marine sediments and ice sheets and glaciers. We report here the development of a flow injection analysis technique, which has been optimised for the simultaneous determination of soluble iron and aluminium in polar ice cores. Iron was determined by its catalytic role in the reduction of N,N-dimethyl-p-phenylenediamene (DPD) to a semiquinonic form (DPDQ) and subsequent absorption spectroscopy at 514 nm. Aluminium was determined by spectroscopic analysis of an aluminium-lumogallion complex that exhibits fluorescence at 560 nm. These techniques have been applied to a section of Greenland ice dated to 1729-1733 AD and indicate that volcanism is a source of highly soluble aluminium and iron.

Development of a method for simultaneous analysis of PCDDs, PCDFs, PCBs, PBDEs, PCNs and PAHs in Antarctic air.

The development of a unique analytical method for the determination of five classes of persistent organic pollutants (POPs) in atmospheric gas and the particle phase through gas chromatography coupled to high-resolution mass spectrometry is presented. Every step of the pre-analytical and analytical optimization process is described. Great effort was put into simplifying the traditional techniques, with reference to EPA and literature methods. Automated instruments were used for sample extraction and cleanup in order to enhance repeatability and reduce contamination risks. Unlike most common approaches, no separation of the analytes was performed before the GC analysis in order to avoid sample fractionation and to save time and materials. This allowed low instrumental and method detection limits (pg to sub-pg) to be achieved. Accuracy and precision were tested by fortifying the matrix and analysing standard reference materials (NIST SRM 1649b Urban Dust and 2585 Organic Contaminants in House Dust). The method was applied to five samples from Terra Nova Bay, Antarctica. Concentrations of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) are presented. Lighter compounds dominate the distribution and are mainly present in the gaseous phase. The observed pattern may be attributable to long-range transport. Results are in general agreement with literature data, where available.

Deposition in St. Mark's Basilica of Venice.

Atmospheric pollutants may cause damage to monuments and historical buildings. Besides air contaminants, soluble salts are also responsible for stone deterioration and decay in outdoor and indoor monuments. The problem of how to conserve works of arts thus requires a deep knowledge of contaminants' concentration and distribution inside buildings. In this work, water-soluble ions inside St. Mark's Basilica in Venice were studied, with the aim of understanding their principal source and distribution inside the building. With the aid of Fourier transform infrared spectroscopy and scanning electron microscopy analysis, the interaction between ions and surface's material was also investigated. Ion chromatographic analysis of depositions highlighted a large amount of "deteriorating agents" such as sulphates and chlorides. A possible source in the innermost area of the basilica has been found for formates and nitrates. On the contrary, a decrease of chloride, from the entrance to the innermost area, has been found, which indicates that the source is outside the building. It is emphasized that different contaminants behave differently on different material, and the effect of pollution inside churches and monuments is not easy to predict. Wood and brick seem to react differently than stone and mortar to the damaging action of salts and pollutants. The present work should be considered a useful tool for the future preservation of St. Mark's Basilica in Venice.

Distribution and seasonal variability of trace elements in atmospheric particulate in the Venice Lagoon.

Size distribution and selected element concentrations of atmospheric particulate matter (PM) were investigated in the Venice Lagoon, at three sites characterised by different anthropogenic influence. The PM(10) samples were collected in six size fractions (10-7.2, 7.2-3.0, 3.0-1.5, 1.5-0.95; 0.95-0.49 and <0.49 µm) with high volume cascade impactors, and the concentration of 17 elements (Al, As, Ca, Cd, Co, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Sr, V, Zn) was determined by inductively coupled plasma quadrupole mass spectroscopy. More than 1 year of sampling activities allowed the examination of seasonal variability in size distribution of atmospheric particulates and element contents for each site. At all the stations, particles with an aerodynamic diameter <3 µm were predominant, thus accounting for more than 78% of the total aerosol mass concentration. The highest PM(10) concentrations for almost all elements were found at the site which is more influenced by industrial and urban emissions. Similarity in size distribution of elements at all sites allowed the identification of three main behavioural types: (a) elements found mainly within coarse particles (Ca, Mg, Na, Sr); (b) elements found mainly within fine particles (As, Cd, Ni, Pb, V) and (c) elements with several modes spread throughout the entire size range (Co, Cu, Fe, K, Zn, Mn). Factor Analysis was performed on aerosol data separately identified as fine and coarse types in order to examine the relationships between the inorganic elements and to identify their origin. Multivariate statistical analysis and assessment of similarity in the size distribution led to similar conclusions on the sources.

Elemental labeling for the identification of proteinaceous-binding media in art works by ICP-MS.

In the history of art, artists have used many different organic compounds to dissolve pigments and apply them onto a support to obtain a paint layer. Proteins were used with success from the Middle Ages up to the Renaissance, and the traditional protein sources were animal parts (skins, tendons and bones) or milk and eggs. Moreover, some of these materials are commonly used as adhesive. In this paper, the first application of the metallomic analytical technique to the identification of proteins in artworks is reported. Samples were derivatized with DTPA/Eu and the derivatization procedure was evaluated by matrix-assisted laser desorption/ionization time-of-flight before high performance liquid chromatography inductively coupled plasma MS analysis. This study has been carried out on laboratory models prepared in-house for method development, resulting in the correct identification of the different classes of proteinaceous binders typically used. In addition, some unknown paint layer samples have been analyzed demonstrating that the method is applicable to very small sample amounts (0.6 mg), which are compatible with the amount normally available for this kind of analysis. The results obtained demonstrate the effectiveness of the method, suggesting the potential future use as novel diagnostic tool in the scientific study of artworks.

Determination of rare earth elements in tomato plants by inductively coupled plasma mass spectrometry techniques.

In recent years identification of the geographical origin of food has grown more important as consumers have become interested in knowing the provenance of the food that they purchase and eat. Certification schemes and labels have thus been developed to protect consumers and genuine producers from the improper use of popular brand names or renowned geographical origins. As the tomato is one of the major components of what is considered to be the healthy Mediterranean diet, it is important to be able to determine the geographical origin of tomatoes and tomato-based products such as tomato sauce. The aim of this work is to develop an analytical method to determine rare earth elements (RRE) for the control of the geographic origin of tomatoes. The content of REE in tomato plant samples collected from an agricultural area in Piacenza, Italy, was determined, using four different digestion procedures with and without HF. Microwave dissolution with HNO3 + H2O2 proved to be the most suitable digestion procedure. Inductively coupled plasma quadrupole mass spectrometry (ICPQMS) and inductively coupled plasma sector field plasma mass spectrometry (ICPSFMS) instruments, both coupled with a desolvation system, were used to determine the REE in tomato plants in two different laboratories. A matched calibration curve method was used for the quantification of the analytes. The detection limits (MDLs) of the method ranged from 0.03 ng g(-1) for Ho, Tm, and Lu to 2 ng g(-1) for La and Ce. The precision, in terms of relative standard deviation on six replicates, was good, with values ranging, on average, from 6.0% for LREE (light rare earth elements) to 16.5% for HREE (heavy rare earth elements). These detection limits allowed the determination of the very low concentrations of REE present in tomato berries. For the concentrations of REE in tomato plants, the following trend was observed: roots > leaves > stems > berries.

Speciation analysis of mercury in seawater from the lagoon of Venice by on-line pre-concentration HPLC-ICP-MS.

A method based on the coupling of HPLC with ICP-MS with an on-line pre-concentration micro-column has been developed for the analysis of inorganic and methyl mercury in the dissolved phase of natural waters. This method allows the rapid pre-concentration and matrix removal of interferences in complex matrices such as seawater with minimal sampling handling. Detection limits of 0.07 ng L(-1) for inorganic mercury and 0.02 ng L(-1) for methyl mercury have been achieved allowing the determination of inorganic mercury and methyl mercury in filtered seawater from the Venice lagoon. Good accuracy and reproducibility was demonstrated by the repeat analysis of the certified reference material BCR-579 coastal seawater. The developed HPLC separation was shown to be also suitable for the determination of methyl mercury in extracts of the particulate phase.

Trace elements in winter snow of the Dolomites (Italy): a statistical study of natural and anthropogenic contributions.

Knowledge of the occurrence of trace elements deposited in fresh alpine snow is very limited. Although current sources of major ionic inorganic species have been well established, this is not the case for many trace elements. This manuscript attempts to reconstruct the origin of Ag, Ba, Bi, Cd, Co, Cr, Cu, Fe, Mo, Mn, Pb, Sb, Ti, U, V and Zn in winter surface snow, extensively collected in the Dolomites region (Eastern Alps, Italy). Sampling of surface snow was conducted weekly during the winter 1998 at 21 sites at altitudes ranging from approximately 1000 to approximately 3000 m. This led to a remarkable dataset of trace element concentrations in surface snow from low latitudes. Here we show a preliminary statistical investigation conducted on the 366 samples collected. It was found that V, Sb, Zn, Cd, Mo and Pb have a predominantly anthropogenic origin, linked to the road traffic in the alpine valleys and the nearby heavily industrialised area of the Po Valley. In addition, the occasionally strong Fe and Cr input may reflect the mechanical abrasion of ferrous components of the vehicles. However, much of the Fe along with Mn, U and Ti originates primarily from the geological background of the Dolomites. A marine contribution was found to be negligible for all the trace elements. The origin of other trace elements is less clear: Ag can be possibly attributed to a predominantly anthropogenic origin while Cr, Co, Cu and Ba are usually from crustal rocks but different than the Dolomites.

Rare earth elements determined in Antarctic ice by inductively coupled plasma--time of flight, quadrupole and sector field-mass spectrometry: An inter-comparison study.

Inductively coupled plasma mass spectrometry (ICP-MS) is a suitable tool for multi-element analysis at low concentration levels. Rare earth element (REE) determinations in standard reference materials and small volumes of molten ice core samples from Antarctica have been performed with an ICP-time of flight-MS (ICP-TOF-MS) system. Recovery rates for REE in e.g. SPS-SW1 amounted to approximately 103%, and the relative standard deviations were 3.4% for replicate analysis at REE concentrations in the lower ngL(-1) range. Analyses of REE concentrations in Antarctic ice core samples showed that the ICP-TOF-MS technique meets the demands of restricted sample mass. The data obtained are in good agreement with ICP-Quadrupole-MS (ICP-Q-MS) and ICP-Sector Field-MS (ICP-SF-MS) results. The ICP-TOF-MS system determines accurately and precisely REE concentrations exceeding 5ngL(-1) while between 0.5 and 5ngL(-1) accuracy and precision are element dependent.

Isotopic analysis of lead present in the cinnabar of Roman wall paintings from the Xth Regio "(Venetia et Histria)" by ICP-MS.

The analysis of Roman wall paintings coming from Verona, Vicenza, Padova, Pordenone and Trieste evidentiated the presence of cinnabar. In this work, the isotopic composition (206)Pb, (207)Pb and (208)Pb of trace of lead present in cinnabar is reported, via ICP-MS measurements. The isotopic ratio values are compared with the values obtained from samples coming from Roman wall paintings of Pompeii and from the mines of Almaden (Spain) Monte Amiata (Grosseto Italy) and Idria (Slovenia). All the isotopic data can be represented by a "field" ranging from Huelva, to Almeria Spanish provinces. This trend could be due to the mixing of cinnabar products treated in Rome.