The environmental dissemination of antibiotic resistance genes (ARGs) and heavy metal resistance genes (HMRGs) is increasingly driven by complex interactions between metal contaminants and bacterial communities. Conjugative plasmids and biofilm formation are central to these processes, serving as key vectors and hotspots for horizontal gene transfer (HGT). This review systematically evaluates the influence of heavy metal(loid)s on bacterial biofilm development and plasmid-mediated ARG transfer by analyzing 63 peer-reviewed studies published between 2005 and 2026. Emphasis is placed on metal-specific and concentration-dependent effects, experimental conditions, and variability among bacterial strains. Essential metals, including copper (Cu) and zinc (Zn), frequently promoted conjugation and biofilm development at sub-inhibitory levels, whereas higher concentrations often induced toxicity and inhibited biofilm formation. Conjugative transfer was also enhanced by non-essential metal(loid)s, such as cadmium (Cd), mercury (Hg), arsenic (As), and silver (Ag) in certain studies, with Hg showing increases of up to approximately 4.5-fold. Modulatory factors, including reactive oxygen species (ROS) and changes in membrane permeability, were identified as critical mechanisms that may influence HGT. This review highlights the need for mechanistic and environmentally relevant investigations that integrate metal–biofilm–conjugation dynamics to gain deeper insight into the propagation of ARGs under realistic exposure conditions.

Biodegradable polyesters (BPEs) are increasingly being promoted as sustainable alternatives to conventional plastics, particularly in applications where biodegradability offers an advantage because material retrieval is impractical or impossible. Agriculture is a typical example of such applications. However, the growing interest in BPEs has also raised legitimate concerns regarding potential environmental side effects, especially the formation and fate of biodegradable microparticles (“microbioplastics”) in soils. This review critically examines the current understanding of the degradation mechanisms, ecological interactions, and environmental implications of BPEs under soil conditions. Evidence suggests that, at environmentally and agriculturally realistic loading rates, most effects on soil properties are transient and comparable to those induced by natural biodegradable organic inputs such as lignocellulose. Fragmentation of and biofilm formation on BPEs, often interpreted as adverse effects, are in fact inherent stages of microbial degradation and carbon cycling. Overall, assessing the impact of BPEs on soil ecosystems remains a highly relevant and rapidly evolving research area, requiring adherence to sound scientific principles, realistic exposure scenarios, and standardized methodologies. Integrating microplastic characterization and temporal analyses into future certification and testing frameworks will strengthen the scientific foundation for evaluating the environmental safety of these materials and support their responsible implementation in sustainable agriculture and soil management.

Volatile fatty acids (VFAs), as intermediate products of anaerobic digestion, are attracting increasing attention due to their potential applications as effective carbon sources and precursors for high-value biofuels and biochemicals. Methanogenesis inhibition is a key to VFAs production, yet current strategies are limited by poor mechanistic insight and potential toxicity. This study has systematically evaluated the existing methanogenesis inhibition strategies qualitatively and quantitatively, with a focus on elucidating the inhibitory mechanisms and factors. Bayesian mixed effects model provides robust statistical evidence that these inhibition methods reliably suppress methanogenesis and enhance VFAs production across diverse conditions. Particularly, chemical inhibition methods have consistently performed well in methane inhibition (highest density interval [HDI] 1.99–6.11) and VFAs accumulation (HDI [0.016, 0.079]). However, chemical inhibitors may lack selectivity and have the potential to accidentally inhibit non-target microbial communities. In contrast, operational and physical inhibition methods are effective in promoting VFAs accumulation (HDIs [0.063, 0.153] and [0.026, 0.111]), but their impact on methane inhibition was unstable with HDIs that are either wide or crossing zero, possibly due to methanogens recovery and subsequent VFAs consumption. Biological inhibition has limited effectiveness in both areas with HDIs crossing zero, likely because it is still in the early stages of development and requires further research. By integrating microbial, physicochemical, and systems-level insights, this work offers a perspective on the rational design of carbon redirection strategies toward VFAs production using anaerobic biotechnology.

Chlorinated paraffins (CPs), especially short-chain (SCCPs) and medium-chain (MCCPs) homologues, have become a global concern due to their highly toxic and persistent. However, there remains a limited and fragmented understanding of their distribution and hotspots across diverse environmental matrices worldwide, and research on effective control measures is even more deficient. This study investigated the global occurrence of CPs in multiple environmental matrices and reviewed existing degradation technologies. Emissions from industrial activities, product usage and environmental matrices exchanges have led to widespread CPs contamination mainly encompassing SCCPs and MCCPs, with average concentrations of 10−3–103 ng/m3 in atmosphere, 10–103 ng/L in water and 1–105 ng/g dw in sediment, as well as 1–106 ng/g dw in soil. In contrast, data on long-chain CPs (LCCPs) remain extremely limited. The available long-term atmospheric monitoring demonstrated both the effectiveness of regulatory controls and the delayed environmental response due to long-range atmospheric transport. The environmental migration of CPs is strongly influenced by carbon chain length and degree of chlorination. Current degradation technologies primarily focus on pyrolysis, photolysis, photocatalysis, microbial degradation, and phytoremediation. Mechanisms and efficiency analyses revealed that major challenges include by-products and the limited scalability of technologies beyond laboratory settings. By systematically linking contaminations profiles to suitable treatment options, we proposed a targeted CPs pollution remediation strategy. These insights aim to advance global CPs government and support the implementation of the Stockholm Convention.

Transition metal activation represents a flexible strategy to enhance oxidant reactivity for aqueous contaminants abatement. Soluble manganese ions (Mn(II)) have garnered increasing attention owing to the redox activity, low toxicity, and high natural abundance. Although Mn(II) reacts with multiple oxidants with a broad spectrum of rate constants, its activation capability is relatively limited. Generally, colloidal manganese dioxide (cMnO2) is generated as the stable oxidation product of Mn(II), exhibiting pronounced catalytic promotion of pollutant oxidation via its surface interactions with oxidants and/or organics. Introduction of complexing ligands not only influences the reactivity of Mn(II) and its reaction kinetics with oxidants but also affects the reaction pathway, typically shifting the mechanism from one-electron to two-electron transfer. This converts Mn(II) to ligand-stabilized Mn(III), which is the key intermediate for high-valent Mn(V)-oxo species generation. Alternative pathways involving the Mn(IV)-oxo species are also proposed. These reactive manganese species enhance pollutant removal efficiency in Mn(II)/ligand/oxidant systems. Collectively, Mn(II) and its derivatives Mn(III)/Mn(IV) engage in intricate reactions with diverse oxidants. Elucidating the reaction chemistry is of paramount importance for advancing the scientific understanding and practical applications of Mn-based oxidation technologies. So, this work provides an integrated review on this topic. Reaction pathways and kinetics between Mn(II) and common oxidants (i.e. H2O2, persulfates, HOCl, ClO2, periodate (PI), peracetic acid (PAA), Mn(VII), Fe(VI), and O3) were first summarized. Mechanisms of cMnO2 surface-catalyzed pollutant degradation by oxidants were interpreted. The pivotal role of Mn(III) in ligand-assisted Mn(II)/oxidant systems was discussed. Finally, knowledge gaps in this field were identified.

A bacteria Log Reduction Value (LRV) database was created from a systematic literature review extracting bacteria LRVs for chemical and physical water treatment processes. Data extraction resulted in 4,822 bacteria log reduction datapoints for multiple disinfection and membrane removal treatment technologies. Additional 3,209 datapoints were extracted for amoeba, fungi, bacterial spores, extremophiles, and radio-tolerant bacteria. The resulting database is sortable by treatment type, pH, temperature, disinfectant residual level, organism type, C × T (i.e., disinfectant residual [C] multiplied by contact time [T]) or UV light dose, and LRV. The database is available open source via Mendeley Data at: https://doi.org/10.17632/6wvt558dwh.1. For multiple disinfectants, treatment levels required to achieve LRV goals for some opportunistic bacteria of public health relevance are greater than published C × T levels required for virus and protozoa inactivation in the Surface Water Treatment Rule (SWTR). Comparing the most resistant bacteria (Legionella pneumophila and Mycobacterium spp.) to Giardia lamblia C × T, and considering calculated median and 95th percentile C × T levels to achieve 3-log10 reduction, the required bacteria C × T can be from 0.5- (half, comparing median value) to 2-fold more (comparing 95th percentile value) than Giardia lamblia C × T for chloramine disinfection, 5- to 10-fold more for chlorine dioxide disinfection, 70- to 80-fold more for ozone disinfection, and 250- to 270-fold more for chlorine disinfection. Low-pressure UV light dosage required to achieve 3-log10 reduction of bacteria falls within requirements for Giardia lamblia and virus in the SWTR. The database is available to water practitioners to assess different bacterial management goals (e.g., enteric vs. opportunistic pathogens) by exploring log reduction relationships for specific treatment and organism pairings.

The increasing environmental issues, driven by the depletion of fossil fuel reserves and excessive carbon emissions, have put the world’s attention toward finding sustainable solutions. Among various solutions, microalgae emerge as a promising zero-carbon alternative, addressing both biofuel production and carbon sequestration. This review provides a comprehensive analysis of cultivation methods for microalgae, biofuel conversion techniques (bioethanol and biodiesel), and their role in reducing/eliminating greenhouse gas (GHGs) emissions. Recent developments in cultivation methods, such as photobioreactors and open-pond cultivation have shown encouraging results regarding the CO2-capturing potential of microalgae. Specific microalgal strains, such as Chlorella vulgaris and Chlorella sp. exhibit high biomass productivity (0.4 and 1.21 g/L/d, respectively) and CO2 fixation rates (0.49 and 0.25 g/L/d, respectively), standing out as the most viable for biofuel synthesis. Additionally, this review compares various cultivation systems based on techno-economic analysis (TEA) with an aim to highlight cost-effective and industrially feasible systems. Among the analyzed strains, Nannochloropsis oceanica outperformed the other strains in terms of biodiesel productivity (0.36 g/L/d), production costs ($1.5/L), and EROI (13.5). This makes it an excellent choice for large-scale biofuel production. By integrating biofuel production and CO2 sequestration, this review identifies key challenges and future research directions for economically feasible microalgal bioenergy solutions.

Estimates of greenhouse gas emissions from river networks remain highly uncertain in many parts of the world, leading to gaps in global inventories and preventing effective management. In-situ sensor technology advances, coupled with mobile sensors on robotic sensor-deployment platforms, will allow more effective data acquisition to monitor carbon cycle processes influencing river CO2 and CH4 emissions. However, if countries are to respond effectively to global climate change threats, sensors must be installed more strategically to ensure that they can be used to directly evaluate a range of management responses across river networks. We evaluate how sensors and analytical advances can be integrated into networks that are adaptable to monitor a range of catchment processes and human modifications. The most promising data analytics that provide processing, modeling, and visualizing approaches for high-resolution river system data are assessed, illustrating how multi-sensor data coupled with machine learning solutions can improve both proactive (e.g. forecasting) and reactive (e.g. alerts) strategies to better manage river catchment carbon emissions.

Fundamental knowledge gaps still exist in the exposome, especially regarding analytical space coverage, mapping and prioritization of a very large number of diverse chemical structures. This review focuses on the contributions of suspect and non-target screening (NTS) to contaminants characterization and toxicity assessment in drinking water. A comprehensive review of publications from 2013-2024 revealed only 172 substances identified with certainty using NTS and in 17 countries. The analytical approaches, their complementarity, effectiveness and use with compound identification frameworks are discussed. The use of ‘intelligent’ tools (including machine learning) to aid with substance identification, prioritization and toxicity assessment is emerging. Strategies for integration of NTS in epidemiology are also considered, including re-use of existing data. NTS holds great potential for chemical exposure assessment from drinking water and its contribution to the exposome.

Uranium is a naturally occurring radionuclide with chemical toxicity, derived from deposits formed through complex processes. In recent years, uranium utilization activities have increased uranium levels in the soil environment, posing serious threats to soil quality, food safety, and human health. Phytoextraction of uranium contamination is currently a cutting-edge topic that has attracted significant attentions. To date, several studies have examined the behavior and impact of uranium in various aspects of its mineralization and "soil-plant" system. Accordingly, we focused on the full life cycle of uranium within the "ore-soil-root-shoot" system, based on published work from 2015 to 2024, to provide an updated review of significant research findings and theories. Here, we present the following key aspects: (i) the factors influencing uranium mineralization, including material sources, transport processes, and precipitation mechanism; (ii) both natural and anthropogenic sources that contribute uranium entry into the soil; (iii) uranium toxicity generated by its radio- and chemo-toxicities; (iv) the toxic effects of uranium and plant detoxification; (v) the internal mechanisms of uranium uptake and translocation by plant roots; and (vi) the role of transpiration in the transport of uranium from roots to the aboveground plant parts. Phytoextraction is an eco-friendly and efficient method for remediation of uranium-contaminated soils, and combined measures such as chelating agents’ application and microbial inoculation are effective to obtain the satisfying results. We also identify and summarize the gaps in current research, providing a reference for future related studies.