Environmental Chemistry Letters最新文献

Microplastic pollution in aquatic environments has emerged as a significant environmental concern, posing risks to ecosystems and human health. Urban stormwater runoff has been identified as a major source of microplastics, with microplastic concentrations reaching up to six times higher than those in wastewater treatment plant effluents. Given the increasing urbanization and inadequate waste management, effective mitigation strategies are urgently needed to prevent the discharge of microplastics into natural water systems. Green infrastructure, designed for sustainable stormwater management, has gained attention as a promising approach to reducing microplastic pollution while providing additional environmental benefits. Here, we review various green infrastructure technologies, including bioretention systems, permeable pavements, stormwater ponds, and constructed wetlands, focusing on their effectiveness in microplastic mitigation. Bioretention systems exhibit removal efficiencies ranging from 80% to over 99%, and are particularly effective for particles sized 20 μm or above. Constructed wetlands achieve removal rates between 28 and 75%, effectively treating microplastics in the 100–500 μm range. Permeable pavements demonstrate removal efficiencies of 89–96.6%, especially for particles less than 100 μm. Retention ponds retain 55–98% of microplastics, with sediment retention reaching up to 85%. We found that the performance of these systems is influenced by soil amendments, vegetation, and adsorption-based mechanisms such as biochar applications, which can enhance removal to over 99% under optimized conditions. Phytoremediation with aquatic plants such as Lemna minor achieves a 76% removal rate, while biofilm-based strategies offer slower but potentially sustainable solutions. This review highlights the necessity of integrating multiple green infrastructure approaches to optimize microplastic removal.

Sulfur dioxide pollution by ship emissions can be efficiently decreased by using exhaust gas scrubbers, yet particles can pass through the scrubber and be released into the atmosphere. Here, we studied the impact of using a wet scrubber on the composition of particle emissions, by single-particle analysis. At low engine loads, results show no significant changes in particle composition of metals, salts, and polycyclic aromatic hydrocarbons (PAH). At high engine loads, the scrubber reduced soot and PAH signatures about fourfold. Particles passing through the scrubber undergo minimal chemical changes, except for sulfate uptake. The cleaning effect of wet scrubbers is attributed to the removal of water-soluble gas-phase compounds, diffusion-dominated uptake of ultrafine particles, and wet deposition of coarse particles. The scrubber has little effect on reducing the health and environmental impacts of the remaining particles that pass through it. These emitted particles, primarily in the 60–200 nm size range, constitute a significant portion of the inhalable particle mass and have the potential for long-range transport.

Classical production of construction particleboards with high-grade wood and formaldehyde-based binders induces forest depletion and pollution, calling for alternatives. Here, we designed in situ lignin bonding to transform low-grade woods into high-performance and formaldehyde-free particleboards. This method involves the deconstruction of fine wood particles to soften cell walls, eliminating undesirable water-soluble components while preserving lignin, followed by a thermo-compression molding procedure to facilitate the formation of a compact and cross-linked structure within softened wood particles. Results show that particleboard displays high mechanical strength with a rupture modulus of 66.7 MPa and excellent water resistance with a thickness swelling of 2.1%. The performance of particleboards is enhanced by low wood hardness, small particle size, removal of water-soluble fractions, and preservation of lignin. The self-adhesion technique is straightforward, practical, and scalable.

Nanoplastics are emerging contaminants which can induce intestinal inflammation and dysfunction, yet their possible influence on colorectal tumorigenesis remains unclear. Here, six‑week‑old male mice were exposed to 125 mg/L 80 nm polyethylene nanoplastics, polyethylene nanoplastic/azoxymethane, polyethylene nanoplastics/azoxymethane/dextran sulfate sodium, and controls for 66 days. We assessed intestinal symptoms, colorectal tumorigenesis, and pathological, ultrastructural and molecular changes. Results show more colon tumors, of 18.3 versus 13.5, and heavier tumor burdens, of 113.1 versus 67.7 mm² in the mice treated with nanoplastics/azoxymethane/dextran sulfate sodium. Similarly, there were more colon tumors, of 6.0 versus 2.2, and heavier tumor burdens, of 26.0 versus 7.0 mm² in mice treated with nanoplastics/azoxymethane. Mice treated with nanoplastics alone developed colorectal neoplasms, of 2.9, with tumor burdens of 10.6 mm² and a pathology of polyp. Exposure to nanoplastics promoted tumor‑associated macrophages infiltration; disrupted microvilli, intercellular junctions, and the mitochondrial structures of colonic epithelium; and activated inflammation‑associated signaling pathways. Overall, the exposure to polyethylene nanoplastics facilitates the initiation and promotion of colorectal tumorigenesis, possibly by affecting mitochondrial structure and aggravating chronic colitis.