The Great Acceleration of fragrances and PAHs archived in an ice core from Elbrus, Caucasus

Chemicals of Emerging Arctic Concern in north-western Spitsbergen snow: Distribution and sources

Personal care products contain chemicals that are considered of emerging concern in the Arctic. In this study, a selected group of personal care products was investigated in the snowpack on north-western Spitsbergen. We report a preliminary study on the spatial and seasonal distribution of 13 ingredients commonly found in personal care products, including fragrance materials, UV filters, BHT and BPA. Possible sources and deposition processes are discussed. Experimental analyses utilizing GC-MS/MS, were complemented with outputs from the HYSPLIT transport and dispersion model. The results reveal the presence of all selected compounds in the snow, both in proximity to and distant from the research village of Ny-Ålesund. For some of these chemicals this is the first time their presence is reported in snow in Svalbard. These chemicals show different partitioning behaviours between the particulate and dissolved phases, affecting their transport and deposition processes. Additionally, concentrations of certain compounds vary across different altitudes. It is observed the relevance of long-range atmospheric transport during winter at most sites, and, regardless of the proximity to human settlements, snow concentrations can be influenced by long-distance sources. This study highlights the need for detailed information on CEACs' physical-chemical properties, considering their potential impact on fresh and marine waters during the snowmelt under climate change.

The seasonal change of PAHs in Svalbard surface snow

The Arctic region is threatened by contamination deriving from both long-range pollution and local human activities. Polycyclic Aromatic Hydrocarbons (PAHs) are environmental tracers of emission, transport and deposition processes. A first campaign has been conducted at Ny-Ålesund, Svalbard, from October 2018 to May 2019, monitoring weekly concentrations of PAHs in Arctic surface snow. The trend of the 16 high priority PAH compounds showed that long-range inputs occurred mainly in the winter, with concentrations ranging from 0.8 ng L-1 to 37 ng L-1. In contrast to this, the most abundant analyte retene, showed an opposite seasonal trend with highest values in autumn and late spring (up to 97 ng L-1), while in winter this compound remained below 3 ng L-1. This is most likely due to local contributions from outcropping coal deposits and stockpiles. Our results show a general agreement with the atmospheric signal, although significant skews can be attributed to post-depositional processes, wind erosion, melting episodes and redistribution.

Hybrid Targeted/Untargeted Screening Method for the Determination of Wildfire and Water-Soluble Organic Tracers in Ice Cores and Snow

Wildfires can influence the earth's radiative forcing through the emission of biomass-burning aerosols. To better constrain the impacts of wildfires on climate and understand their evolution under future climate scenarios, reconstructing their chemical nature, assessing their past variability, and evaluating their influence on the atmospheric composition are essential. Ice cores are unique to perform such reconstructions representing archives not only of past biomass-burning events but also of concurrent climate and environmental changes. Here, we present a novel methodology for the quantification of five biomass-burning proxies (syringic acid, vanillic acid, vanillin, syringaldehyde, and p-hydroxybenzoic acid) and one biogenic emission proxy (pinic acid) using solid phase extraction (SPE) and ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry. This method was also optimized for untargeted screening analysis to gain a broader knowledge about the chemical composition of organic aerosols in ice and snow samples. The method provides low detection limits (0.003-0.012 ng g^-1), high recoveries (74 ± 10%), and excellent reproducibility, allowing the quantification of the six proxies and the identification of 313 different molecules, mainly constituted by carbon, hydrogen, and oxygen. The effectiveness of two different sample storage strategies, i.e., re-freezing of previously molten ice samples and freezing of previously loaded SPE cartridges, was also assessed, showing that the latter approach provides more reproducible results.

Advanced bioremediation by an amalgamation of nanotechnology and modern artificial intelligence for efficient restoration of crude petroleum oil-contaminated sites: a prospective study

Crude petroleum oil spillage is becoming a global concern for environmental pollution and poses a severe threat to flora and fauna. Bioremediation is considered a clean, eco-friendly, and cost-effective process to achieve success among the several technologies adopted to mitigate fossil fuel pollution. However, due to the hydrophobic and recalcitrant nature of the oily components, they are not readily bioavailable to the biological components for the remediation process. In the last decade, nanoparticle-based restoration of oil-contaminated, owing to several attractive properties, has gained significant momentum. Thus, intertwining nano- and bioremediation can lead to a suitable technology termed 'nanobioremediation' expected to nullify bioremediation's drawbacks. Furthermore, artificial intelligence (AI), an advanced and sophisticated technique that utilizes digital brains or software to perform different tasks, may radically transfer the bioremediation process to develop an efficient, faster, robust, and more accurate method for rehabilitating oil-contaminated systems. The present review outlines the critical issues associated with the conventional bioremediation process. It analyses the significance of the nanobioremediation process in combination with AI to overcome such drawbacks of a traditional approach for efficiently remedying crude petroleum oil-contaminated sites.

Effects of environmental concentrations of the fragrance amyl salicylate on the mediterranean mussel Mytilus galloprovincialis

Amyl salicylate (AS) is a fragrance massively used as a personal care product and following the discharged in wastewaters may end up in the aquatic environment representing a potential threat for the ecosystem and living organisms. AS was recently detected in water of the Venice Lagoon, a vulnerable area continuously subjected to the income of anthropogenic chemicals. The lagoon is a relevant area for mollusc farming, including the Mediterranean mussels (Mytilus galloprovincialis) having an important economic and ecological role. Despite high levels of AS occurred in water of the Lagoon of Venice, no studies investigated the possible consequences of AS exposures on species inhabiting this ecosystem to date. For the first time, we applied a multidisciplinary approach to investigate the potential effects of the fragrance AS on Mediterranean mussels. To reach such a goal, bioaccumulation, cellular, biochemical, and molecular analyses (RNA-seq and microbiota characterization) were measured in mussels treated for 7 and 14 days with different AS Venice lagoon environmental levels (0.1 and 0.5 μg L^-1). Despite chemical investigations suggested low AS bioaccumulation capability, cellular and molecular analyses highlighted the disruption of several key cellular processes after the prolonged exposures to the high AS concentration. Among them, potential immunotoxicity and changes in transcriptional regulation of pathways involved in energy metabolism, stress response, apoptosis and cell death regulations have been observed. Conversely, exposure to the low AS concentration demonstrated weak transcriptional changes and transient increased representation of opportunistic pathogens, as Arcobacter genus and Vibrio aestuarianus. Summarizing, this study provides the first overview on the effects of AS on one of the most widely farmed mollusk species.

Cryoconites as biogeochemical markers of anthropogenic impact in high mountain regions: analysis of polyaromatic pollutants in soil-like bodies

The globalisation and omnidirectional character of anthropogenic processes has challenged scientists around the world to estimate the harmful effects of these processes on ecosystems and human health. Polycyclic aromatic hydrocarbons (PAHs) is one the most infamous group of contaminants, originated both from natural and anthropogenic processes. They could transport to high latitudes and altitudes through atmospheric long-distance transfer and further enter ecosystems of these vulnerable regions by deposition on terrestrial surfaces. An interesting object for tracking transboundary contamination processes in high mountain ecosystems is called cryoconite. Cryoconite, a dark-coloured supraglacial sediment which is abundant in polar and mountain environments, is considered as a storage of various pollutants, including PAHs. Thus, it may pose a risk for local human health and ecosystem through short-distance transfer. Studied cryoconite sediments were collected at the surface of Skhelda and Garabashi glaciers, Central Caucasus high-mountain region, as well as mudflow, moraine material and local soils at the Baksan Gorge in order to examine levels of their contamination. We analysed the content of 15 priority polyaromatic compounds from the US EPA list and used the method of calculation of PAHs isomer ratios with the purpose of identifying their source. To estimate their potential toxicity, Benzo[a]pyrene (BaP) equivalents were calculated. Maximum concentration was defined for NAP (84 ng×g-1), PHE (40 ng×g-1) and PYR (47 ng×g-1), with the minimum concentration for ANT (about 1 ng×g-1). The most polluted material is a cryoconite from Garabashi glacier because of local anthropogenic activities and long-distance transfer. High-molecular weight PAHs are dominated in PAHs composition of almost all samples. The most common sources of PAHs in studied materials are combustion processes and mixed pyrolytic/petrogenic origin. Toxicity levels of separate PAHs did not exceed the maximum permissible threshold concentrations values in most cases. However, the sum of PAHs in BaP equivalents exceed the threshold values in all samples, in some of them more than twice.

Chemical hazard in glacial melt? The glacial system as a secondary source of POPs (in the Northern Hemisphere). A systematic review

Toxicity of compounds belonging to persistent organic pollutants (POPs) is widely known, and their re-emission from glaciers has been conclusively demonstrated. However, the harmful effects associated with such secondary emissions have yet to be thoroughly understood, especially in the spatial and temporal context, as the existing literature has a clear sampling bias with the best recognition of sites in the European Alps. In this review, we elaborated on the hazards associated with the rapid melting of glaciers releasing organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs). To this end, we collated knowledge on: (1) the varying glacier melt rate across the Northern Hemisphere, (2) the content of POPs in the glacial system components, including the less represented areas, (3) the mechanisms of POPs transfer through the glacial system, including the importance of immediate emission from snow melt, (4) risk assessment associated with POPs re-emission. Based on the limited existing information, the health risk of drinking glacial water can be considered negligible, but consuming aquatic organisms from these waters may increase the risk of cancer. Remoteness from emission sources is a leading factor in the presence of such risk, yet the Arctic is likely to be more exposed to it in the future due to large-scale processes shifting atmospheric pollution and the continuous supply of snow. For future risk monitoring, we recommend to explore the synergistic toxic effects of multiple contaminants and fill the gaps in the spatial distribution of data.

Fragrance materials (FMs) affect the larval development of the copepod Acartia tonsa: An emerging issue for marine ecosystems

Fragrance materials (FMs) are used in a variety of detergents and cosmetics, including household and personal care products. Despite their widespread use and the growing evidence of their occurrence in surface waters worldwide, very little is known about their toxicity towards marine species, including a key component of the marine food webs such as copepods. Thus, we investigated the toxicity of six of the more long-lasting and stable commercial fragrances, including Amyl Salicylate (AMY), Oranger Crystals (ORA), Hexyl Salicylate (HEX), Ambrofix (AMB), Peonile (PEO), and Benzyl Salicylate (BZS), to assess their ability to impair the larval development of the calanoid copepod Acartia tonsa. FMs inhibited the development of A. tonsa significantly at concentrations by far lower than the effect-concentrations reported in the literature for aquatic species. The more toxic FMs were HEX (EC₅₀ = 57 ng L^-1), AMY (EC₅₀ = 131 ng L^-1) and ORA (EC₅₀ = 766 ng L^-1), while the other three compounds exerted toxic effects at concentrations higher than 1000 ng L^-1 (LOEC at 1000 ng L^-1 for PEO and BZS, and at 10,000 ng L^-1 for AMB). Early life-stage mortality was unaffected by FMs at all the tested concentrations. A comparison with water concentrations of FMs reported in the literature confirmed that FMs, especially HEX and AMY, may act as contaminants of potential concern in many aquatic habitats, including urban areas and remote and polar environments.

Deposition of PFAS 'forever chemicals' on Mt. Everest

Mt. Everest, one of the most coveted climbing mountains on earth, also contains the highest altitude chemical contamination on land. For the first time, meltwater and snow samples from Mt. Everest's Khumbu Glacier were analyzed for "forever chemicals" per- and polyfluoroalkyl substances (PFAS). Our research team utilized solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify pollutants sampled from Everest Base Camp, Camp 1, Camp 2, and Everest Balcony. From the 14 PFAS compounds tested for, we found perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexanoic acid (PFHxA) in Mt. Everest snow and meltwater. The highest concentrations found were 26.14 ng/L and 10.34 ng/L PFOS at Base Camp and Camp 2, respectively. However, PFAS species were seen within 1-2 orders of magnitude in all sampling sites with detection, potentially suggesting a widespread presence on the mountain. Our samples are the highest altitude PFAS samples ever retrieved and indicate the need for further sampling both on Mt. Everest and in the below-glacier watershed.