Environmental Science & Technology Letters Environ.最新文献

Uneven global distribution of phosphate rock deposits and the supply chains to transport phosphorus (P) make P fertilizers vulnerable to exogenous shocks, including commodity market shocks; extreme weather events or natural disasters; and geopolitical instability, such as trade disputes, disruption of shipping routes, and war. Understanding bidirectional risk transmission (global-to-local and local-to-global) in P supply and consumption chains is thus essential. Ignoring P system interdependencies and associated risks could have major impacts on critical infrastructure operations and increase the vulnerability of global food systems. We highlight recent unanticipated events and cascading effects that have impacted P markets globally. We discuss the need to account for exogenous shocks in local assessments of P flows, policies, and infrastructure design choices. We also provide examples of how accounting for undervalued global risks to the P industry can hasten the transition to a sustainable P future. For example, leveraging internal P recycling loops, improving plant P use efficiency, and utilizing legacy soil P all enhance system resiliency in the face of exogenous shocks and long-term anticipated threats. Strategies applied at the local level, which are embedded within national and global policy systems, can have global-scale impacts in derisking the P supply chain.

The recent rediscovery of offshore DDT waste dumping in the Southern California Bight (SCB) has led to questions about the extent and type of pollution in deep ocean environments. We used a nontargeted analysis to identify halogenated organic compounds (HOCs), including DDT+, in sediment in the San Pedro Basin. Additionally, we examined the chemical profiles of deep ocean biota inhabiting the SCB to assess the bioavailability of DDT+ and HOCs to the deep ocean food web. We detected 49 HOCs across all samples, including 15 DDT+ compounds in the sediment and 10 DDT+ compounds in the biota. Compounds included tris(4-chlorophenyl)methane (TCPM) and its isomers and three unknown DDT-related compounds previously identified in marine mammals. No clear trends were identified regarding DDT+ distribution in sediments. High DDT+ body burdens were found in biota irrespective of collection location, indicating widespread DDT+ contamination in the deep ocean of the SCB. TCPMs were detected in all biota samples except a single surface species, indicating that deep ocean sediment may be a source of DDT+ to the marine food web. This study demonstrates that the analysis of the larger suite of DDT+ is critical to trace deep ocean pollution of DDT in the SCB.

We develop a new framework, hyporheic reaction potential (HRP), to predict the influence of oxidation-reduction reactions on metal fate and transport in streams using data from tracer studies and geochemical sampling. HRP, with energy flux units [KJ m^–2 s^–1], is a metric calculated from both the physical and chemical properties of the hyporheic zone. We apply the HRP framework for iron reactions, using existing geochemical and geophysical data from two metal-impacted alpine streams at high and low flow. In these two systems, HRP delineates contrasting controls on iron fate and transport with biogeochemical controls in Mineral Creek and physical controls in Cement Creek. In both systems, HRP scales with discharge and hyporheic-zone extent as flows change seasonally, which demonstrates the ability of HRP to capture physical aspects of chemical reactions in the hyporheic zone. This paper provides a foundation on which HRP can be expanded to other solutes where chemical gradients in the hyporheic zone control reaction networks, making it broadly applicable to redox cycling in stream systems. This framework is useful in quantifying the role of the hyporheic zone in sourcing and storing metal(loid)s under varying hydrologic conditions with implications for water quality, mine remediation, and regional watershed management.

Environmentally persistent free radicals (EPFRs) have been linked to the generation of reactive oxygen species (ROS) and adverse health effects. However, there remains a knowledge gap regarding the dynamic changes in reactivity and toxicity during the decay process of EPFRs emitted from incomplete solid fuel burning, which are identified as a primary source of EPFRs. Here, we report the decay behavior of EPFRs in particulate matter (PM) emitted from typical solid fuel burning and the associated ROS generation and cytotoxic effects. The EPFRs in freshly produced PM first undergo rapid exponential decay with lifetimes ranging from 15 to 97 h and are categorized as fast-decay EPFRs. The relative content of fast-decay EPFRs was 40.5 ± 15.3%, while the remaining portion, defined as slow-decay EPFRs, displayed an extremely slow rate of decay. ROS generation and cytotoxicity decreased by 38.8 ± 11.4% and 62.5 ± 12.6%, respectively, following the depletion of fast-decay EPFRs, which were further demonstrated to be responsible for the variations in PM reactivity and toxicity. These new findings underscore the importance of considering the decay process of EPFRs in assessments of PM toxicity.

The emerging field of insect-mediated plastic degradation opened a new avenue for addressing the escalating issue of plastic pollution. These insects provide a natural model for studying plastic biodegradation, highlighting the significance of such biological processes. However, our understanding remains limited, largely due to the complexity of the insect gut ecosystem. We highlight key aspects of the underlying feeding and degradation mechanisms in insects, including their feeding behaviors, gastrointestinal metabolic activities, and the roles of microbial communities and enzymes. Additionally, we provide key recommendations for advancing research in this innovative area, underlining the critical need for an in-depth exploration of these natural biodegradation systems.

Understanding the composition and concentration of pollutants in the gym environment is crucial for evaluating the potential health risks associated with physical exercise. Here submicron aerosol composition in a basement gym was characterized by a high-resolution aerosol mass spectrometer. Our results showed higher fraction of organic aerosol (OA) in particulate matter indoors (50%) than outdoors (40%). Positive matrix factorization identified two distinct gym-related OA factors, i.e., siloxane OA (SiOA) and cigarette smoke OA (CSOA). Unexpectedly high concentrations of particulate siloxane, up to 6 μg m^–3 and contributing 7–11% of OA were observed, and the variations of SiOA were strongly correlated with carbon dioxide emissions from human activities. The source of SiOA is likely from the lubricant of silicone polymers used in fitness equipment during exercise. Additionally, the presence of CSOA in the gym, on average contributing 6–7% of OA, is primarily linked to outdoor transport during ventilation. Our results highlight the significance of thorough investigations of air quality across different gyms with varying equipment, human occupancy, and ventilation conditions which is pivotal for implementing effective measures that ensure healthy indoor air quality and minimize potential health risks associated with exercise in gyms.

Entanglement, often associated with the interaction of large marine plastics and larger animals, has not yet been reported in the context of microplastics (MPs) and small organisms. In this study, Daphnia magna was exposed to fibrous and fragmentary MPs at concentrations ranging from 1 to 1000 items/mL for 7 days. The results revealed that fibrous MPs tended to entangle with the second antennae and tail claws of D. magna, whereas fragmentary MPs merely adhered to the surface of the daphnids but do not exhibit entanglement. Additionally, the swimming speed and projected area of swimming trajectories of daphnids significantly decreased in the 100 items/mL group compared with the control. However, the occurrence of entanglement and slow swimming was less pronounced in the 1000 items/mL group due to the aggregation of fibrous MPs. Scanning electron microscopy revealed that D. magna possessed a rich spine structure on the surface of their bodies, particularly on their antennae and tails. The entanglement of D. magna by fibrous MPs resembled the action of manufactured “hook and loop”. Overall, the results of this research revealed that entanglement is observed in small animals exposed to fibrous MPs, highlighting the direct biological effects of MPs beyond ingestion.

An operational real-time surface ozone (O₃) retrieval (RT-SOR) model was developed that can provide a gapless diurnal cycle of O₃ retrievals with a spatial resolution of 6.25 km by integrating Chinese Land Data Assimilation System (CLDAS) data and multisource auxiliary information. The model robustly captures the hourly O₃ variability, with a sample-based (station-based) cross-validation R² of 0.88 (0.85) and RMSE of 14.3 μg/m³ (16.1 μg/m³). An additional hindcast-validation experiment demonstrated that the generalization ability of the model is robust (R² = 0.75; RMSE = 21.9 μg/m³). Compared with previous studies, the model performs comparably or even better at the daily scale and fills the gaps in terms of missing hourly O₃ data within the 24-hour cycle. More importantly, underpinned by the RT availability of CLDAS data, the hourly concentration of O₃ can be updated in RT, which is expected to advance our understanding of the diurnal cycle of O₃ pollution in China.

Microplastics, which are indicative of global change, pervade all ecosystems, and their mass surpasses the total animal biomass of Earth. Pollination, the transfer of pollen among plants, is a key process that allows for plant reproduction and plant population prevalence. Plant reproduction could be altered by microplastics at several stages: plastic-polluted animals can act as pollinators, and airborne plastic fragments can be deposited on the stigmatic surfaces of pistils, interfering with pollen–pistil interactions, clogging pollen tube development and reducing seed production. To test this hypothesis, we examined the impact of polypropylene fragments (<63 μm) deposited on stigmatic surfaces on seed production by studying the Andean-yellow monkeyflower Erythranthe lutea (Phrymaceae). We combined hand-pollination treatments and ultrastructural observations and reported the adverse effect of polypropylene fragments on seed production when this material was deposited on stigmas, but the mass and germination levels of the obtained seeds did not differ. Optical and scanning electron microscopy observations of the pollen tube ultrastructure revealed that pollen tube development was disrupted by the addition of polypropylene fragments. The results point to the potential deleterious effects of microplastics on a crucial ecosystem process, pollination, which might have consequences for most angiosperms and crop production.

The purpose of this Global Perspective is to discuss the ecological impacts of desalination intakes in coastal ecosystems and to highlight current global policies and trends. Suggestions are provided based on regulatory needs and knowledge gaps required to better evaluate the ecological risks of such facilities. Desalination has emerged as an increasingly popular response to the intensifying global water demands and shortages in recent decades. As of 2019, the number of operational desalination facilities was estimated at nearly 16,000, with 48% located in the Middle East and North Africa. Current trends indicate that new and planned facilities are overwhelmingly membrane-based desalination facilities, specifically seawater reverse osmosis (SWRO) facilities. Large-scale SWRO facilities draw millions of gallons each day from source waters, potentially leading to the impingement, entrapment, and entrainment of massive numbers of aquatic organisms, with potential implications for community structure and function via multiple indirect mechanisms. Despite these potentially devastating environmental impacts, there remains a paucity of enforceable regulations pertaining to intake structure siting, design, and operation of large desalination facilities worldwide.