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Criteria for EUROAIRNET. The EEA air quality monitoring and information network. EEA Technical Report, 12
1999
2015
This study critically examines the workflow for untargeted analysis of volatile organic compounds (VOCs) in ambient air, from sampling strategies to data interpretation by using GC-HRMS. While untargeted approaches are well-established in liquid chromatography (LC) due to advanced-deconvolution tools and extensive metabolomic libraries, their application in gas chromatography (GC) remains less developed, particularly for VOCs. The high structural isomerism of VOCs and the relative novelty of GC-based untargeted methodologies present unique challenges, including limited software tools and reference libraries. Air samples from suburban and rural sites in central Italy were analyzed to explore chemical diversity and address methodological gaps. This study evaluates critical decisions, such as sampling strategies, extraction techniques, and data-processing workflows, highlighting the limitations of automated deconvolution tools and the need for manual validation. Results revealed distinct source contributions, with suburban areas showing higher levels of anthropogenic compounds and rural areas dominated by biogenic emissions. This work underscores the potential of GC-HRMS untargeted analysis to advance environmental chemistry, while addressing key pitfalls and providing practical recommendations for reliable application. By bridging methodological gaps, it offers a roadmap for future studies aiming to integrate untargeted and targeted approaches in air quality research.
MDPI
2025
2016
Critical review of the atmospheric composition observing capabilities for monitoring and forecasting
WMO
2025
2007
This cross-cutting review focuses on the presence and impacts of per- and polyfluoroalkyl substances (PFAS) in the Arctic. Several PFAS undergo long-range transport via atmospheric (volatile polyfluorinated compounds) and oceanic pathways (perfluorinated alkyl acids, PFAAs), causing widespread contamination of the Arctic. Beyond targeting a few well-known PFAS, applying sum parameters, suspect and non-targeted screening are promising approaches to elucidate predominant sources, transport, and pathways of PFAS in the Arctic environment, wildlife, and humans, and establish their time-trends. Across wildlife species, concentrations were dominated by perfluorooctane sulfonic acid (PFOS), followed by perfluorononanoic acid (PFNA); highest concentrations were present in mammalian livers and bird eggs. Time trends were similar for East Greenland ringed seals (Pusa hispida) and polar bears (Ursus maritimus). In polar bears, PFOS concentrations increased from the 1980s to 2006, with a secondary peak in 2014–2021, while PFNA increased regularly in the Canadian and Greenlandic ringed seals and polar bear livers. Human time trends vary regionally (though lacking for the Russian Arctic), and to the extent local Arctic human populations rely on traditional wildlife diets, such as marine mammals. Arctic human cohort studies implied that several PFAAs are immunotoxic, carcinogenic or contribute to carcinogenicity, and affect the reproductive, endocrine and cardiometabolic systems. Physiological, endocrine, and reproductive effects linked to PFAS exposure were largely similar among humans, polar bears, and Arctic seabirds. For most polar bear subpopulations across the Arctic, modeled serum concentrations exceeded PFOS levels in human populations, several of which already exceeded the established immunotoxic thresholds for the most severe risk category. Data is typically limited to the western Arctic region and populations. Monitoring of legacy and novel PFAS across the entire Arctic region, combined with proactive community engagement and international restrictions on PFAS production remain critical to mitigate PFAS exposure and its health impacts in the Arctic.
Elsevier
2024
2016
2017
2016
Crumb rubber toxicity in coastal marine systems
Crumb rubber granulate (CRG) produced from end of life tires (ELTs) is commonly applied on indoor and outdoor synthetic turf pitches (STPs), playgrounds, safety surfaces and walkways. In addition to fillers, stabilizers, cross-linking agents and secondary components (e.g. pigments, oils, resins, fibers), ELTs contain high levels of organic additive compounds and heavy metals. While previous environmental studies have focused on terrestrial soil and freshwater ecosystems, in Norway many sites applying CRG are coastal. In the current study, the organic chemical and metal content of 'fresh' and 'weathered' CRG and their seawater leachates was investigated, and the uptake of crumb rubber by the brown crab (Cancer pagurus) was studied as an example of an exposure route for CRG to coastal marine organisms. A combination of pyrolysis gas chromatography mass spectrometry (py-GC-MS) and chemical extraction followed by GC-MS analysis revealed similar organic chemical profiles for pristine and weathered CRG, including additives such as benzothiazole, N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine and a range of polycyclic aromatic hydrocarbons (PAHs) and phenolic compounds (e.g. bisphenols). ICP-MS analysis indicated g/kg quantities of Zn and mg/kg quantities of Fe, Mn, Cu, Co, Cr, Pb and Ni in the CRG. A mixture of organic additives, metals and other inorganic compounds readily leached from the CRG into seawater. Benzothiazole was the organic compound with highest concentration (average of 136 mg/L), while PAHs (ranging from <LOD to 0.58 mg/L) and phenolic compounds (e.g. 2,4-bisphenol F and 4,4’-bisphenol F at 0.012 and 0.006 mg/L, respectively) were present in low abundance. Zn was the most abundant metal in the leachates (23.8 mg/L) followed by Fe (0.08 mg/L) and Co (0.06 mg/L). While organic chemical concentrations in the leachates stabilized within days, metals continued to leach out over the 30 day period. Brown crabs were exposed to two concentrations of CRG (0.5 and 0.05 g/L) in two size fractions (5 mm and 250 µm diameter) for 24 hours. Ingestion of the rubber and subsequent gut evacuation were studied over 5 days. Image analysis of filtered stomach contents confirmed uptake of rubber particles in different sizes, but also efficient gut evacuation upon transfer to clean water. We discuss the implications of CRG and leachate toxicity in acute and long-term exposure scenarios for marine coastal ecosystems.
2020
2018