Microplastics (MPs) and nanoplastics (NPs) infiltrate every environmental matrix, presenting increasing risks to ecological stability and human well-being. This review compiles worldwide data from 228 studies to examine trends specific to polymers, shape, source of origin, transport mechanisms, and the emerging risks of MPs/NPs across marine, freshwater, groundwater, terrestrial, and atmospheric environments. Polyethylene (PE) and polypropylene (PP) are the leading fibrous contaminants in freshwater systems, soil, and aquifers, mainly due to packaging, textiles, and wastewater discharges. Marine ecosystems gather fragment-shaped PE and PP from coastal waste breakdown and fishing practices, whereas atmospheric MPs/NPs—mainly polyethylene terephthalate (PET), polyamide (PA), and polyvinyl chloride (PVC) fibers—arise from synthetic fabrics and urban pollutants. The research demonstrates how the shapes of particles and polymer composition influence the environmental behaviour of various pollutants in diverse settings. Emerging threats involve MPs/NPs acting as carriers for pathogens (e.g., SARS-CoV-2), interfering with ocean carbon sequestration through “plastic snow,” and hastening sea-ice melting by reducing albedo. Climate interactions are bidirectional—rising temperatures accelerate plastic fragmentation, while MPs alter greenhouse gas fluxes by modifying soil microbial activity. Analytical progress (FTIR, Raman spectroscopy) predominates polymer characterization, but there are still gaps in identifying NPs and measuring long-term ecotoxicological effects. The study also highlights how ocean currents, atmospheric movements, and water cycle mechanisms contribute to the movement of plastics to remote areas, such as Arctic ice and underground water sources. Although studies on MPs and NPs are increasing, notable gaps remain in comprehending their lasting effects and properties across various environmental matrices. This research establishes a framework for prioritizing interventions to combat the plastic pollution crisis by connecting source-to-sink pathways and cross-matrix interactions.

Organic and inorganic contaminants are entrained into environmental systems through natural and anthropogenic processes, such as mining activities, manufacturing, and waste disposal. In terrestrial and aquatic environments, the contaminant(s) remediation can be achieved by immobilization, thereby inhibiting their dispersal and bioavailability. Mobilization, through leaching and plant uptake, is another process of pollutant removal. Phytoremediation has attracted attention as an eco-friendly alternative for the remediation of contaminated environments. However, the safe management of post-phytoremediation contaminated biomass poses many practical challenges. Understanding the fate of the pollutants in the plants allows the estimation of the possible transfer of the contaminants to the food chain ascertain by-products or residues during biofuel production. Metal-enriched fractions could be used as a valuable source of novel catalysts or reusable materials. The safe conversion of biomass into energy may require sequestering contaminants at any step of the process, preferably upstream of the energy conversion or as a pre-treatment of plant biomass. Through gasification or pyrolysis of post-remediation biomass, bioenergy products (including syngas, oil, hydrogen gas, biochar, and hydrochar) can be used for heating and electricity generation. A comparative evaluation among pyrolysis, gasification, combustion, and liquefaction/fermentation processes for biofuel production from post-phytoremediation biomass suggests that pyrolysis is the strategy with the lowest transfer of toxic metals to the final products. This review presents critical discussions of the processes involved in phytoremediation of contaminated environments, the redistribution of contaminants within plant biomass, the sustainable management of post-phytoremediation biomass, and the unintended environmental consequences of phytoremediation.

Ensuring access to affordable, reliable, sustainable, and modern energy (SDG 7) remains a global challenge, with 660 million people projected to lack electricity by 2030. However, increasing electrification, particularly in developing regions, risks amplifying material extraction, impacting sustainable resource management (SDG 12.2). Using 2015 as the base year, this study quantifies the potential direct and indirect material requirements of achieving universal electrification by 2030. Our findings show a 17.2% increase in the electricity sector’s material footprint, with the transition to low-carbon sources adding another 6.9%. The majority of new electricity demand is expected to occur in Africa and Asia-Pacific, with Africa also leading in material extraction. Despite these increases, the electricity sector’s overall contribution to global material use remains relatively modest. This study highlights SDG trade-offs and emphasizes the need for locally produced electricity to not only improve energy access but also generate broader economic benefits along the supply chain.

The power sector plays a crucial role in promoting global carbon neutrality. This study investigates the key drivers behind the low-carbon transition of the power sector in 78 countries from 1990 to 2022, using a comprehensive analytical framework that integrates both temporal and spatial index decomposition methods. From a temporal perspective, the primary driver of carbon emission trends is the growing electricity consumption in developing nations. Mitigation strategies have evolved from improving the efficiency of thermal power generation to restructuring the energy mix. Spatially, differences in carbon intensity are primarily influenced by variations in energy composition, particularly the distribution and types of thermal and non-fossil energy sources. Our findings highlight that Europe has made significant progress in reducing its carbon intensity, while Asia faces considerable challenges, largely due to its continued reliance on fossil fuels. The pathway to low-carbon development varies across countries, depending on factors such as resource endowments, technological capabilities, and social acceptance. Nations rich in hydropower typically prioritize its use, while only a limited number have adopted nuclear energy, influenced by both technical feasibility and public trust in nuclear safety. In countries with limited hydropower and nuclear resources, wind and solar power often emerge as the primary alternatives, though their adoption is heavily influenced by local climatic and weather conditions. These findings lead to three key policy implications: first, using carbon intensity as a relative measure offers a more equitable and meaningful way to assess the progress of developing countries, balancing their development needs with global decarbonization goals; second, national strategies for low-carbon transitions should be tailored to each country’s unique context. More emphasis should be placed on transforming the overall energy structure, rather than focusing solely on improving thermal power efficiency; third, for developing countries with limited hydropower and nuclear resources, international cooperation through technology sharing, financial support and capacity building is crucial to eliminating development barriers and promoting sustainable energy development.

Anaerobic digestion (AD) is a potential approach to treat organic wastes for energy and resource recovery. Adding various carbon materials in AD is being studied owing to its positive effects on the overall governing mechanisms. This study investigated the effect of adding seven different carbon materials in AD reactors in two sets of experiments. In the first set, five commercially available carbon materials were added to the batch assay, treating α-cellulose under anaerobic and oxygen-stressed conditions. The activated carbon amended reactor steadily provided methane yield even under oxygen-stressed conditions. In the second set, locally prepared hydrochar (HC) and pyrochar (PC) derived from biogas slurry were added to the anaerobic co-digestion of organic wastes. The reactor amended with HC, and its process water (PW) provided 478 mL/g·VS_input of biomethane yield while the PC-amended reactor achieved 411 mL/g·VS_input. This enhancement was attributed to functional groups in HC, volatile acids in PW, and PC’s pH buffering properties. Further, the grey relational analysis revealed that the HC and PW amendment is the best route for improved AD process efficiency. In short, from the two sets of experiments, these findings suggest that activated carbon, PC, and HC (with PW) have potential for improving AD efficiency. However, further research is needed to evaluate their long-term effectiveness and scalability.

Pyrolysis is a technology that converts plastics into fuel or chemicals at high temperatures, offering significant advantages over other plastic waste disposal methods. Currently, the energy required for plastic pyrolysis usually comes directly or indirectly from fossil fuels, thus causing carbon emissions. This study investigates a plastic pyrolysis method using solar energy as the heat source, aiming to reduce carbon emissions and achieve carbon neutrality. A numerical model was developed to investigate temperature distribution, reaction rates, yields, and energy utilization in plastic pyrolysis. Simulation results indicated that under certain conditions, the plastic conversion exceeded 73%, with an energy efficiency above 17.3%. Heat flux, structural parameters of porous medium and inlet parameters of plastic are the key factors affecting the plastic pyrolysis. Heat flux had a significant impact on the system performance, plastic conversion remained below 30% when heat flux was below 0.3