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Hurricanes can introduce metals into coastal systems. Unfortunately, metal concentrations are unknown in many hurricane prone locations. Here we measured vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, molybdenum, cadmium, antimony, barium, lead, and uranium in surface water, sediments, and seagrass (Thalassia testudinum) collected in seagrass beds and marinas around The Abacos, The Bahamas in November 2019, May 2020, and June and December 2021 to establish a post-Hurricane Dorian baseline, assess changes post-storm, and understand bioconcentration in seagrass. Metal concentrations were higher in marinas and several increased over time. Also, metal profiles in sediments became more similar over time. Together, these suggest that metals were impacted by Hurricane Dorian and are either returning to pre-storm conditions or increasing due to recovery-related activities. Thalassia testudinum uptakes most metals more readily from surface water than sediments. Therefore, seagrasses may phytoremediate metals, but also transfer metals to higher trophic levels. 

The characterization of nanoparticles (NPs) in hydrocarbon matrices using single particle inductively coupled plasma mass spectrometry (spICP-MS) is underdeveloped. There are less than ten publications using spICP-MS in hydrocarbon matrices, and none have applied the technique to determine NP concentration and size distribution in asphaltenes after in-situ upgrading of heavy oils via solvent deasphalting. To our knowledge, no studies have used spICP-MS to track the nature of NP additives in the asphaltene fraction in hydrocarbons without adulteration of the sample. Particle number concentrations (PNC) derived from spICP-MS in hydrocarbon matrices are reported for the first time. Fe2O3 PNC increased by an order of magnitude, and NiO PNC increased 28 % compared to samples without additives, indicating that NPs were reasonably well-dispersed in the asphaltenes. Ionic concentrations were higher for Ni than Fe, which showed negligible changes in all samples. Here, we report the lowest size detection limits recorded for Fe2O3 NPs (32 nm ± 1 nm) using spICP-MS in hydrocarbon matrices. Further, NiO and Fe2O3 NP sizes matched the initial sizes added to the oil before precipitation, providing evidence that the nature of the NPs does not change after deasphaltation and subsequent mixing with asphaltenes. This study expands our understanding of the interactions between metal NPs and asphaltenes when used as co-precipitants during in situ upgrading of heavy crude oil. 

The short- and long-term impacts of nanoparticles (NPs) in consumer products are not fully understood. Current European Union (EU) regulations enforce transparency on products containing NPs in cosmetic formulations; however, those set by the U.S. Food and Drug Administration are lacking. This study demonstrates the potential of single-particle inductively coupled plasma tandem mass spectrometry (spICP-MS/MS) as a screening method for NPs present in powder-based facial cosmetics (herein referred to as FCs). A proposed spICP-MS/MS method is presented along with recommended criteria to confirm particle presence and particle detection thresholds in seven FCs. FC products of varying colors, market values, and applications were analyzed for the presence of Bi, Cr, Mg, Mn, Pb, Sn, Ag, Al, and Zn NPs based on their ingredient lists as well as those commonly used in cosmetic formulations. The presence of NPs smaller than 100 nm was observed in all FC samples, and no correlations with their presence and market value were observed. Here, we report qualitative and semi-quantitative results for seven FC samples ranging in color, brand, and shimmer. 

Rare earth elements (REEs) make up a group of unique elements with diverse applications in energy, medicine, and technology. Increasing global demand and limited supplies have led to exploring the economic viability of domestic feedstock extraction from sources such as coal. Little is known about the release of REEs from coal due to the environmentally driven processes of photodissolution. In this study, the photodissolution of water-soluble REEs and dissolved organic carbon (DOC) from subbituminous coal was investigated using laboratory-simulated sunlight exposures. The effects of the solar intensity, temperature, and exposure time on photodissolution were also examined. Following irradiation, water-soluble REE and DOC concentrations increased significantly above nonirradiated controls, indicating photodissolution is a significant process. Both solar intensity and exposure time influenced photodissolution rates, while temperature did not. Results from this study provide motivation to further investigate the photodissolution pathways of REEs from subbituminous coal and interaction with DOC ligands, given that photosolubilized REEs may be organic associated. These findings may have implications, both positive and negative, for the environmental impact of REEs. 

Abstract High‐resolution mass spectrometry (HRMS) has become a vital tool for dissolved organic matter (DOM) characterization. The upward trend in HRMS analysis of DOM presents challenges in data comparison and interpretation among laboratories operating instruments with differing performance and user operating conditions. It is therefore essential that the community establishes metric ranges and compositional trends for data comparison with reference samples so that data can be robustly compared among research groups. To this end, four identically prepared DOM samples were each measured by 16 laboratories, using 17 commercially purchased instruments, using positive‐ion and negative‐ion mode electrospray ionization (ESI) HRMS analyses. The instruments identified ~1000 common ions in both negative‐ and positive‐ion modes over a wide range ofm/zvalues and chemical space, as determined by van Krevelen diagrams. Calculated metrics of abundance‐weighted average indices (H/C, O/C, aromaticity, andm/z) of the commonly detected ions showed that hydrogen saturation and aromaticity were consistent for each reference sample across the instruments, while average mass and oxygenation were more affected by differences in instrument type and settings. In this paper we present 32 metric values for future benchmarking. The metric values were obtained for the four different parameters from four samples in two ionization modes and can be used in future work to evaluate the performance of HRMS instruments.