Environmental science. Advances最新文献

Ocean acidification is a major threat to coral reefs worldwide, with reduced growth already reported in the hydrocoral Millepora alcicornis (Linnaeus, 1758) under these conditions. Inhibition of enzymes related to energy metabolism is hypothesized as one of the mechanisms associated with the physiological impacts of ocean acidification. Therefore, a mesocosm experiment was conducted to investigate whether three levels of decreasing seawater pH could alter the activity of key enzymes involved in the energy metabolism in M. alcicornis. Hydrocorals were acclimated to marine mesocosm conditions for 20 days and then exposed to different seawater pH levels [ambient pH (8.1) and experimental pH (7.8, 7.5 and 7.2)] for 16 and 30 days. Endpoints analyzed included the activity of key enzymes involved in the regulation of the glycolytic pathway (hexokinase and pyruvate kinase), aerobic energy production via the Krebs cycle (citrate synthase) and anaerobic energy production via lactate formation (lactate dehydrogenase). The results obtained show that only citrate synthase was affected by seawater acidification, as a marked reduction in its activity was observed at all experimental pH levels tested (7.8, 7.5 and 7.2). This finding indicates that reduced growth previously reported for M. alcicornis under seawater acidification conditions can be explained, at least in part, by a negative impact on the Krebs cycle, a major pathway involved in aerobic energy production.

Freshwater beach quality is routinely tested by measuring fecal indicator bacteria, which can assess water quality but cannot identify sources of fecal contamination. We compared eDNA metabarcoding and microbial source tracking (MST) digital PCR methods to identify fecal contamination sources in water and sand at four urban Lake Ontario beaches and two nearby river mouth locations. eDNA sequences matched mammal, bird, and fish taxa known in the study area. Human eDNA sequences were prominent in all water and sand samples such that they had less value for discriminating between sewage occurrence at sites. Mallard duck, muskrat, beaver, raccoon, gull, robin, chicken, red fox, and cow eDNA sequences were common across all locations. Dog, Canada goose, and swan eDNA sequences were more common in Toronto beach waters, suggesting localized sources. MST results were generally consistent with eDNA, such as finding the Gull4 DNA marker and the human mitochondrial DNA marker in most water and sand samples. Chicken, cow, and dog eDNA sequences and the human bacterial MST DNA marker often showed a higher frequency of occurrence on Beach Action Value (BAV) exceedance days. The surprisingly widespread detection of chicken and cow eDNA sequences was likely from incompletely digested human food, raising caution for interpreting eDNA results related to food animals in sewage-contaminated urban settings. Combined use of MST and eDNA methods provided a more comprehensive characterization of potential fecal contamination sources, including diverse wildlife species at the human–animal One Health interface, that can guide targeted beach-specific water monitoring and risk management strategies.

Local sources of persistent organic pollutants (POPs) and Chemicals of Emerging Arctic Concern (CEACs) from use in communities, shipping, and industrial activity contribute to contamination as does long-range environmental transport. Increased human activity in the Arctic as the climate warms may enhance the significance of local sources. Furthermore, climate change may lead to secondary sources of POPs and CEACs from existing reservoirs in the Arctic. This review examines the emerging evidence for releases from these secondary sources of formerly deposited POPs and CEACs as the Arctic climate warms and the potential for future releases with increased infrastructure development and economic activity. Arctic permafrost degradation represents an important source of natural and anthropogenic polycyclic aromatic hydrocarbons (PAHs), and indications exist of releases of POPs related to permafrost thaw, from previous deposition as well as waste sites. Deposition of POPs and some CEACs to Arctic glaciers is relatively well studied while fewer studies explore the impacts of remobilization. Expansion of economic development has the potential for increasing emissions or creating new sources of CEACs in the Arctic. The predicted northward expansion of agriculture, aquaculture, and ship traffic could bring increased emissions of CEACs to northern waters, including pesticides not previously used in the Arctic. Increased industrial chemical use, e.g. fire-fighting foams, flame retardants, lubricant and plastic additives, is likely to occur following the expansion of infrastructure such as airports, seaports, mining, and oil and gas development. While PAHs are relatively well-studied, there is an urgent need for environmental measurements and modelling of emissions of CEACs associated with the expansion of economic activity in the Arctic as well as to predict the future release of legacy POPs from secondary sources, particularly from permafrost.

Conventional agricultural methodologies often rely on excessive application of fertilizers, pesticides, and water, resulting in adverse environmental consequences such as air/water/soil pollution, soil degradation, etc., thereby diminishing farming efficiency and profitability. The growing demand for sustainable agricultural practices has intensified researchers' interest in exploring biodegradable polymeric particles (BPPs) due to their ability to improve agrochemical delivery, enhance soil health, and mitigate environmental impacts. This review critically examines the state of the art in the design, fabrication, and application of BPPs for agriculture to accomplish sustainable farming. It highlights their significance in enabling controlled release systems, soil improvement, and plant stress tolerance. Key fabrication techniques such as emulsion solvent evaporation, anti-solvent nanoprecipitation, ionotropic gelation, and spray drying are compared based on their scalability, cost-efficiency, and suitability for producing particles with tailored properties. The influence of particle size, shape, and morphology on application efficiency and their biological interactions are thoroughly analyzed, emphasizing the importance of design in optimizing performance. This review also explores the challenges associated with adopting BPPs, including scalability, cost, regulatory compliance, etc., and proposes future directions for advancing their development. By addressing critical gaps and presenting innovative strategies, this review provides a comprehensive framework for integrating biodegradable polymeric particles into sustainable agricultural practices.

Thermal papers are a significant source of exposure to bisphenol A (BPA) and other phenolic compounds (PCs), absorbed through the skin via dermal contact. This study analyzed thermal paper receipts from various commercial settings in Türkiye to assess BPA and its structural analogs. For both deterministic and probabilistic risk assessments, the estimated daily intake (EDI), hazard quotient (HQ), and hazard index (HI) were calculated for the general population and workers exposed via dermal contact from handling thermal receipts. The results showed that BPA and bisphenol S (BPS) were the most frequently detected chemicals (detected in 99% and 100% of samples, respectively) with concentrations ranging from 1.98–1061 μg per g paper and 0.070–210 μg per g paper in thermal paper receipts in Türkiye, respectively. The EDI of PCs based on the mean concentration determined in the samples for the general population ranged between 0.00000184 μg per kg per day and 0.000445 μg per kg per day, whereas it ranged between 0.0000919 μg per kg per day and 0.022 μg per kg per day for occupational exposure of workers. The EDI value based on the mean concentration detected in samples was 0.000445 μg per kg per day and 0.00223 μg per kg per day for the general population and occupational exposure, respectively. Exposure to BPS was lower, resulting in exposure values of 0.000039 μg per kg per day and 0.002 μg per kg per day for the general population and occupational exposure, respectively. Although these mean concentration based exposure levels are below the U.S. EPA reference dose (50 μg per kg per day for BPA), they exceed the more stringent European Food Safety Authority (EFSA) total daily intake (TDI) limits set for BPA (0.0002 μg per kg per day) in some cases, indicating potential health risks. The HQ and HI analyses further underscore the risks, particularly for workers, with HI values surpassing safe thresholds. The study calls for stricter regulations on BPA and its analogs in thermal papers due to the significant risks, even from BPA-free products that use BPS as a substitute.

Phyto-parasitic nematodes are the main risks to the agroecosystem that cause agricultural output to decline in a variety of crops around the world. An intriguing and promising substitute for the chemical practice of shielding plants against the growing hazards of these pathogens lies in biological plant protection. This approach focuses on using biological control agents (BCAs) using microbial-based biocontrol techniques to inhibit the growth of phytopathogens responsible for plant diseases. Microbial BCAs interact with pathogens or plant hosts to increase their resistance, which may be a useful way to control the development of agricultural diseases. However, in comparison to a single strain, microbial consortia with distinct modes of action might exhibit a multifunctional and more resilient effect as a biocontrol. The market is currently offering only a small number of microbial consortia-based biocontrol interventions as these products are still in their infancy of development and demand substantial research to avert phyto-parasitic nematodes. The employment of BCAs to combat phytopathogens will become an increasingly vital component of sustainable agriculture in the future. Thus, this article provides a thorough review of the current status of bacteria and fungi and their microbial consortia-based biocontrol for plant protection research through a biological manner considering upcoming and advanced technological developments. Commercialization of biocontrol products and associated challenges and ways to overcome these hurdles are also discussed as future perspectives. The present review also summarizes the latest research done (particularly the past five years' data) on the activity of BCAs bacteria, fungi and their consortium against various plant pathogens with their enormous benefits for upgrading plant growth and defense mechanisms. The present review efficiently contributes to sustainable development goal 2, which is concerned with food security and sustainable agriculture.

The rising need for rare earth elements (REEs) as critical materials for the development of clean energy technologies, as against the rapid depletion of virgin REE-bearing ores as well as their imbalance in geographical occurrence, calls for thorough search on secondary sources such as coal fly ash, given that the aluminosilicate mineral phase in the waste is enriched in REE particles. To support the geographical diversification of REE sources, there is a need for a comprehensive documentation of REE content and, by extension, the economic potential of fly ash derived from Nigeria's vast coal fields. Eight representative coal fly ash samples generated from coals from Nigeria's major coal belts were collected. Silica and alumina, with respective ranges of 38.1–44.5% and 14–15.98%, accounted for the bulk of the major elements in the samples. Total REE contents in the samples ranged from 874 ppm to 1127 ppm, while the cerium, yttrium, neodymium and lanthanum-dominated rare oxide totals were found to be in the range of 941–2145 ppm across the samples. The outlook coefficients (extractability indices) computed for the samples ranged between 0.8 and 1.3, with 0.7 as the benchmark. The range of percentage of critical REEs in the CFA samples was 28%–36%. This research has successfully explored the relative abundance and distribution of REEs in the studied fly ash samples, providing a theoretical lead for the basis of extraction and waste management.

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Chilli (Capsicum annuum L.) plants are cultivated globally and are valued for their culinary use. One of the major challenges in agriculture is soil salinity, which drastically cuts down crop productivity. However, no information has been reported concerning the effects of biogenic zinc oxide nanoparticles (ZnO NPs), applied as a foliar spray, on the physio-chemical properties of chilli plants under salt stress conditions. The nanoparticles were synthesized using an extract from Acacia nilotica leaves, which acted as a stabilizing and reducing agent. The characteristics of the synthesized nanoparticles were analyzed using various techniques including UV-visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. The pot experiment utilized a salinity level of 50 mM NaCl and tested five concentrations of ZnO NPs (0, 25, 50, 75 and 100 ppm). The results demonstrated that the highest concentration (100 ppm) significantly enhanced growth parameters, including the shoot length (38.6%) and root length (25.5%) compared to the control. Additionally, biochemical parameters such as chlorophyll content (23.3%) and phenolic content (12.5%) enhanced zinc accumulation by 38.7% and decreased oxidative stress malondialdehyde (MDA) by 54.4% and hydrogen peroxide (H₂O₂) by 33.1% as compared to the control. We can conclude that foliar application of 100 ppm of the synthesized biogenic-ZnO NPs may increase chilli growth in a salt-stress environment.

Plastics are extensively involved in our everyday lives, including use as food storage containers. Greater than 95% of plastics produced are derived from petrochemicals. Numerous studies have shown that chemical additives (e.g., phthalates) can migrate out of food grade plastics into foods. Based on this we hypothesize that petrochemicals used in the manufacturer of plastics also migrate into foods. To test this hypothesis, we simulated chemical migration from petrochemical-based plastics under refrigeration and microwave conditions using the United States Food and Drug Administration testing guidelines. Specifically, we measured the amounts of polycyclic aromatic compounds (PACs) migrating from four plastics used heavily in the food industry namely polypropylene, polyethylene, polycarbonate and polyethylene terephthalate glycol. Our results showed that several alkylated and non-alkylated PACs could be detected in the food simulant used with relatively greater amounts of the alkylated PACs compared to their non-alkylated analogs. Data from our studies were used to estimate daily intake where it was shown that the greatest risk of exposure to humans stems from migration of PACs from PE into foods with total EDIs of 1794.4 ± 163.5 and 169.4 ± 23.5 ng per person per day under refrigeration and microwave conditions, respectively. Finally, an assessment of human health risk resulting from dietary exposure to PACs migrating from the four plastics studied under the two usage scenarios, suggests that at current exposure levels, PACs pose negligible cancer risk to humans.