ACS Environmental Au最新文献

Chlorinated paraffins (CPs) are synthetic polychlorinated n-alkanes produced as mixtures of a range of C_xCl_yH_2x–y+2 formulas. CPs have numerous industrial applications but are toxic, long-lived, and environmentally ubiquitous with environmental releases occurring throughout their production, use, and disposal. Short-chain chlorinated paraffins (SCCPs, C_10–13) have been regulated by the United States Environmental Protection Agency since 2009 and by the Stockholm Convention since 2017. SCCP regulation is expected to cause increased production of medium-chain chlorinated paraffins (MCCPs; C_14–17), which are currently under consideration for Stockholm Convention regulations. Thus, there is a need to improve the understanding of MCCP environmental transport, distribution, and fate. Existing measurements are limited in their spatial and temporal coverage. Measurements of CP atmospheric loading are particularly scarce. Historically, these measurements have required long sampling times, obscuring the temporal behavior of atmospheric CPs. We report real-time in situ measurements of 18 gas-phase MCCPs. These measurements were made in the United States Southern Great Plains with nitrate ion chemical ionization mass spectrometry (NO₃–CIMS). The estimated average lower-limit concentration of MCCPs is on the order of single-digit ng/m³. MCCP diel behavior is partially explained by gas-particle partitioning with implications for MCCP transport and lifetimes.

The seafood sector plays a key role in global nutrition but is confronted with significant sustainability challenges including overfishing, marine debris, and the impacts of climate change. In response, several measures have been implemented, such as the introduction of fishing quotas, restrictions on fishing zones, expansion of aquaculture, increased monitoring, and promotion of sustainable consumption. In this context, ecolabels are recognized as tools to encourage sustainable consumption by influencing consumer behavior. However, their effectiveness is hindered by limited consumer awareness, regulatory inconsistencies, and incomplete integration of environmental and social impacts into their criteria. In this Perspective, we explore how these key challenges are incorporated into ecolabel standards and evaluate their potential to influence consumer behavior toward sustainable choices Through a review and insights from a life cycle perspective, we identify critical gaps in current ecolabeling schemes, such as a lack of representativeness, incomplete evaluation, and unclear or nonintuitive communication to consumers, and outline a potential roadmap for their improvement. Addressing these gaps is essential for fostering trust and advancing sustainability in the seafood sector.

Surface-enhanced Raman spectroscopy (SERS) imaging is a highly sensitive, spatially resolved tool for biological and environmental analysis. SERS imaging combines molecular fingerprinting with real-time, in situ detection, with the capacity to address key questions around analyte identification, concentration, and distribution. In biological systems, SERS imaging has enabled sensitive detection of nucleic acids, proteins, and biomarkers. Notable progress includes the detection of miRNAs through nanoassembly and disassembly techniques, as well as bioorthogonal chemistry and antibody-conjugated methods for protein and enzyme imaging. These approaches, along with integration of complementary imaging techniques, have improved SERS imaging for in vivo studies in plant and animal cells. Additionally, SERS imaging of pathogens reveals their distribution and behavior in cellular environments. For environmental applications, SERS imaging has been used to track pesticides, nanoparticles, and heavy metal ions, providing critical insights into contaminant transport and transformation. Furthermore, SERS-based pH and reactive oxygen species (ROS) imaging delivers spatially resolved data on reactive species in biological and environmental microenvironments, aiding in understanding their dynamic roles in various processes. Despite its advantages, SERS imaging faces several challenges. By addressing its limitations, SERS imaging holds promise for broad application in contaminant monitoring, clinical diagnostics, and real-time biological analysis.

Per- and polyfluoroalkyl substances (PFAS) are a group of commonly used compounds, known particularly for their hydrophobic, nonstick properties. Their unique chemistry has also led to their use in ski waxes. While competition rules and some regions have recently banned the use of fluorinated waxes, the persistence of PFAS means they could still be detected for years. Given the hazards and concern about PFAS contamination, this study investigated if PFAS could be detected at a ski area that supports a high-level race program, where these waxes would have been in use for many years. Samples were collected from a variety of locations within a ski area in New Hampshire, USA, to investigate the levels and trends of PFAS in this type of environment. While previous studies have focused on targeted analysis for known PFAS, this study utilized both targeted and nontargeted analysis with high-resolution mass spectrometry (HRMS) and ion mobility to look for new and unexpected PFAS. In the nontargeted analysis, detected peaks were first compared to an internal HRMS PFAS library for identification, and unknown peaks were selected for further scrutiny based on their detected drift time in the ion mobility dimension. An ion mobility filter was created to look for PFAS based on the unique trendlines of collisional cross section (CCS) vs m/z exhibited by halogenated molecules and applied to the list of detected peaks. Using this filter, a number of homologous series of PFAS were tentatively identified, in addition to those found with suspect screening. Two of the series included dioic perfluorinated acids and monohydrogen-substituted perfluoroalkyl carboxylic acids (H-PFCAs). While authentic standards were not available for many of the tentative identifications, two standards were purchased and compared with experimental data to confirm the proposed structures of shorter chain compounds in these series, thus increasing the evidence that identification of the homologous series in these cases was correct. This preliminary study, based on a limited number of water samples, indicated that PFAS contamination could be detected at the ski area. The inclusion of nontargeted analysis provided a more thorough understanding of the contamination’s extent by identifying new species that would be overlooked using targeted methodologies.