Three-dimensional (3D) printing technology is emerging as a transformative tool in eco-environmental research. It innovates environmental analysis technologies, augments environmental purification, alleviates environmental health risks, and fosters ecological sustainability. Nevertheless, most current applications of 3D printing in the eco-environmental domain remain largely confined to laboratory testing stages, with limited translation to large-scale and real-world deployment. In this viewpoint, we review recent progress and critical challenges within this field, while providing strategic perspectives for its future trajectory. We highlight the imperative to integrate cutting-edge 3D printing techniques into eco-environmental research, advance sustainable printing materials, and develop integrated multifunctional devices for environmental monitoring and remediation. Furthermore, we introduce a pioneering conceptual framework: self-sustaining composite artificial biosystems. Here we envision it as a bionic tree, a 3D-printed biohybrid construct that integrates an open microfluidic scaffold with engineered living materials to autonomously maintain biological activity through self-driven internal mass transport. While emulating key morphological and physiological features of natural plants, the bionic tree transcends its natural analogue by enabling synthetic biology-guided environmental remediation, CO2 sequestration, and energy production. We provide an in-depth analysis of the rationale behind this concept, assess its technical feasibility, and present a developmental roadmap for this emerging research direction. Our insights are poised to amplify the contribution of 3D printing to the eco-environmental sector, thereby facilitating environmental pollution control and sustainable development.

Methylmercury (MeHg) is a neurotoxic pollutant threatening aquatic ecosystems and human health. Photodegradation is a key abiotic pathway for MeHg elimination in aquatic systems, yet its underlying mechanisms and controlling factors remain poorly understood. We investigated MeHg photodegradation in the presence of dissolved organic matter (DOM) under varying light conditions and iron ion concentrations. Our results demonstrate that the indirect pathway, mediated by reactive oxygen species (ROS), significantly contributes to MeHg degradation but yields negligible mass-independent fractionation (MIF). In contrast, MIF signatures originate primarily from the direct photodegradation pathway involving MeHg-DOM complexes. Short-wavelength and intense light irradiation enhance the direct pathway, driving the overall MIF enrichment factor more negative (ε199Hg up to -2.51‰). Iron addition promotes the indirect pathway of MeHg and alters MIF characteristics (ε199Hg from -1.40‰ to -0.12‰). Using an isotopic binary mixing model, we provided the first quantitative constraints on the relative contributions of these two pathways. These findings offer new insights into interpreting mercury isotope signatures in natural systems and emphasize the need to consider pathway-specific responses to environmental drivers when using MIF to quantify MeHg photodegradation, which is crucial for accurately assessing its MeHg environmental fate.

Lead exposure has been linked to hypertension; nonetheless, the impact of low-level lead exposure on hypertension risk and underlying mechanisms remain inconclusive. To study how low-level lead exposure contributes to hypertension and potential mediators, data from Southern China were used. This dataset included 54,013 and 5255 lead-exposed workers in the cross-sectional and follow-up studies, respectively. Data collected demographics, physical exams, and assessment of lead exposure levels. Additionally, a subgroup of 1082 workers from a coking facility was included, which included comprehensive assessment of oxidative damage indicators and behavioral factors. We used logistic regression and mixed-effect models, assessed nonlinearity with restricted cubic splines regression, conducted stratified analyses, and performed mediation analysis to explore mechanisms. In the fully adjusted models, workers in the highest quartile exhibited a 38-65 % higher risk of hypertension compared with that of workers in the lowest quartile (OR:1.50, 95%CI:1.38, 1.65), with consistent findings in the follow-up study (OR:1.90, 95 %CI:1.37, 2.63). We found a nonlinear association in the cross-sectional analysis but a linear trend in the follow-up study (Pnon-linear<0.001 and Pnon-linear=0.407, respectively). Prolonged exposure duration and older age were associated with heightened longitudinal blood pressure effects (OR:1.16, 95 %CI:1.03,1.31; β:0.53, 95 %CI:0.18,0.87, Pinteraction<0.05). 8-iso-PGF2α mediated 56.6 % of the effects of lead exposure on blood pressure. These findings indicated a significant association between low-level lead exposure and hypertension. The association appeared to be partially mediated through oxidative stress pathways.

Bioessential elements are essential for maintaining reproductive function, yet their homeostasis may be perturbed during aging. The dynamic regulation of these elements during aging remains insufficiently characterized. Here, a multielement single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) method was established for the quantification of seven bioessential elements, including iron (Fe), copper (Cu), calcium (Ca), zinc (Zn), magnesium (Mg), phosphorus (P) and manganese (Mn). This method was optimized using an integrated strategy to balance sensitivity, transport efficiency, and signal-to-noise ratio, and subsequently applied to quantify elemental contents in sperm collected from mice at different ages. Distinct age-dependent patterns were observed at the single-sperm level. Fe, Cu, and Ca exhibited early life maxima, whereas Zn, Mg, and P reached peak levels in midlife; Mn remained consistently low across all age groups. Interestingly, elemental heterogeneity followed a conserved inverted U-shaped trajectory, reaching a maximum at week 40. Correlation network analysis revealed a significant association between Fe and Mn at the content level, whereas elevated P content and increased heterogeneity were associated with reduced sperm concentration and impaired morphology. Functionally, Zn content was positively correlated with sperm motility, whereas elevated P content and increased heterogeneity were associated with reduced sperm concentration and impaired morphology. Ca, P, Mn, and Fe were more susceptible to dysregulation linked to compromised sperm function, whereas Mg, Zn, and Cu were associated with beneficial outcomes. These findings provide single-cell insights into age-dependent elemental homeostasis and its functional implications for male reproductive aging.

Aqueous interfaces, such as those formed at the surface of microdroplets, can spontaneously generate reactive species, driving the critical redox reactions. This raises a pivotal question: could such laboratory-observed interfacial phenomena be integrated into our broader understanding of pollutant transformation and transport dynamics? In this perspective, we discuss this issue in the context of climate warming and changes in hydrological processes, focusing on how these environmental changes may alter the occurrence, composition, and reaction conditions of aqueous interfaces. Notably, aqueous interfaces may represent a previously underrecognized factor influencing the fate and transport of global pollutants, such as mercury. Bridging laboratory findings with field observations will be essential for linking microscale interfacial chemistry to macroscale environmental outcomes, ultimately improving predictive models of global pollutant cycling in a warming world.

Titanium alloys have emerged as the primary material for orthopedic implants, particularly with the advent of 3D-printing technology that has revolutionized the fabrication of complex, biomimetic porous structures. However, the potential release of wear particles poses a critical safety concern, and due to the relatively short clinical history of these novel implants, in vivo data evaluating their safety profile is still limited. Herein, this study established a single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS) method to quantify low-concentration Ti-containing nanoparticles (Ti-NPs) and total Ti in peri-implant tissues, blood, and major organs of rabbits at 1, 2, 3, and 4 months following implantation. A split-body design was utilized to compare HA-coated and uncoated 3D-printed Ti-6Al-4V implants. The results showed that Ti-containing nanoparticles (Ti-NPs) were detected across all peri-implant tissues, blood, and major organs, with the majority being nanosized (< 100 nm). In the peri-implant tissues, the Ti-NPs exhibited smaller sizes and lower concentrations in the HA-coated group compared to the uncoated group, demonstrating the protective barrier effect of the coating. Furthermore, the release profile showed that ionic titanium was the dominant species (Ti-NPs < 10%), with a distinct systemic distribution pattern. Specifically, by the fourth month, total Ti concentrations in organs decreased sharply due to excretion, whereas Ti-NPs conversely accumulated, with the spleen identified as the primary reservoir. Overall, this work provides important evidence and offers useful guidance for the safety evaluation of 3D-printed implants.

Polyvinyl chloride (PVC) microplastics (MPs) are prevalent in the atmosphere and, as they migrate, inevitably interact with flowing moist air. Despite this, our understanding of the surface chemistry of MPs remains limited. In this study, friction experiments were conducted using a custom-designed model to simulate the interaction between PVC MPs and moist air. The physicochemical changes and reactive species were systematically characterized using ion chromatography, electron spin resonance, and X-ray photoelectron spectroscopy. Results demonstrate that PVC MPs release chloride ions when subjected to friction with moist air in dark conditions. The release of chloride ions is primarily driven by the reduction of CCl bonds, induced by hydrogen radicals generated through electron transfer from water to the polymer during friction. Furthermore, these released chloride ions are subsequently converted into atomic chlorine due to the generation of hydroxyl radicals, a process facilitated by contact electrification between water vapor and the polymer under solar irradiation. Our findings suggest that PVC MPs could act as a source of reactive chlorine, influencing redox processes and potentially impacting air quality in the atmosphere.

Microbial mercury methylation is the key step responsible for the high toxicity and bioaccumulation potential of mercury. Since metabolic pathways serve as a bridge between mercury methylation and microbial activity, studying mercury methylation from the perspective of metabolic pathways will offer valuable insights into its underlying mechanism and integration into microbial metabolism. This review aims to summarize current understanding of the metabolic pathways that supply methyl groups for mercury methylation and to elucidate the relationships between them. The acetyl-coenzyme A pathway is extensively studied and well recognized for its role in methyl group transfer. The Wolfe cycle, representing the methanogenesis pathway in methanogenic archaea, has recently been identified as a distinct source of methyl groups contributing to mercury methylation. In addition, at the chemical level, S-adenosyl-L-methionine from the methionine biosynthesis pathway has been shown to donate a methyl group to mercury via the HgcAB complex, although this process has not yet been validated in vivo. Finally, the dimethylsulfoniopropionate degradation pathway is proposed as a speculative and potential route for mercury methylation. By integrating these pathways, we provide a comprehensive overview of their interconnections, demonstrating that microbial mercury methylation is embedded within the broader framework of one-carbon metabolism. The close association between methylation and one-carbon flux suggests that mercury methylation may function as an interspecies competition strategy that enhances microbial survival in mercury-rich environments. This pathway-centered perspective advances our understanding of the biochemical basis of microbial mercury methylation and may inform future research into its environmental controls and microbial ecology.

Heavy and essential metals coexist in a cell, collectively participate in cellular biological processes, and lead to overall health consequences. However, current analytical strategies cause information loss when using aggregated features and are unable to establish comprehensive associations between single-cell metallomic data and health outcomes. We developed an analytical framework with more accurate characterization of multimetal distribution features, enabling the integration of single-cell metallomic data into health-related studies. We used quantiles to comprehensively extract the features of multimetals in spermatozoa population. Then, machine learning and factor analysis further consolidated key features into interpretable indices of multimetal co-occurrence characteristics. This framework addressed the conservation of the pseudobulk method and bias of the single-cell method, due to a more detailed characterization and appropriate integration of multimetal features at single-cell resolution. We showcase a negative association between multiple metals and sperm motility in the Bayesian Kernel Machine Regression (BKMR) model with a 10% increase in the collective features of 34 metals corresponding to a 3.3% reduction in sperm motility. Notably, the contribution of the multifaceted effects of lead and platinum suggests that dynamic changes in metal distribution may hold biological significance comparable to their total content. Finally, the generalizability of this analytical framework was validated with an additional single-cell metallomic data set. This method facilitates the application of single-cell metallomic measurement techniques in health effect studies, providing deeper insights for understanding the collective biological roles of metals in multicell organisms.

Soil lead (Pb) contamination represents a global environmental challenge, with well-documented adverse effects on both ecosystems and human health. Although Pb-containing nanoparticles (Pb NPs) constitute a significant, yet poorly characterized, fraction of Pb in soils, their origins remain difficult to ascertain due to the chemical complexity of soil matrices and the heterogeneity of Pb contamination sources. In this study, we developed a comprehensive strategy for the characterization and source tracing of Pb NPs in soils using single-particle inductively coupled plasma-mass spectrometry (spICP-MS). First, we established a robust protocol for the qualitative and quantitative characterization of tetrasodium pyrophosphate (TSPP)-extracted Pb NPs from soil samples using spICP-quadrupole-MS (spICP-Q-MS). Then, by leveraging quasi-instantaneous, multi-isotope Pb measurements (206Pb, 207Pb, and 208Pb) at the single-particle level via spICP-time-of-flight-MS (spICP-TOF-MS), we identified the region-specific sources of soilborne Pb NPs across four representative Chinese cities (Beijing, Shaoguan, Xiong'an, and Zhuzhou) by integrating isotopic fingerprinting (208Pb/206Pb and 206Pb/207Pb) with the MixSIAR Bayesian mixing model. Our results demonstrate that Pb NPs can serve as highly sensitive tracers for assessing the extent of soil Pb pollution and for distinguishing geographically distinct Pb contamination sources. We anticipate that this approach will advance the mechanistic understanding of Pb biogeochemistry and improve source apportionment in soil ecosystems.

Nanoplastics (NPs) in aquatic environments raise concerns as carriers that alter the bioavailability of co-occurring pollutants, such as cadmium (Cd), affecting combined toxicity. Precision toxicology now demands single-cell assessments to provide novel insights into pollutant interactions. In this study, we utilized a 3D-printed droplet microfluidic platform integrated with time-resolved analysis (TRA)─inductively coupled plasma mass spectrometry (ICP-MS)─to investigate the uptake behavior of single algal cells exposed to Cd and Eu-containing polystyrene (PS) NPs. 3D printing enables rapid prototyping and design flexibility for optimized microfluidic chips, while the monolithic structure eliminates assembly errors, reduces dead volume, and supports large-scale production. The droplet platform offers high-throughput single-cell encapsulation; coupled with TRA-ICP-MS, it minimizes cross-contamination and enhances sensitivity for multielement single-cell analysis. Single-cell analysis revealed that coexposure increased both the proportion of Eu/Cd-containing cells and the uptaken Eu/Cd content. The adsorption of Cd2+ imparted a more positive surface charge to PS NPs. This promoted heterogeneous aggregation between algal cells and PS NPs, thereby enhancing the bioavailability of PS/Cd2+ to the algae. Complementing these single-cell measurements, bulk-cell assays were conducted to evaluate the toxicological impacts of coexposure to Cd and PS NPs on microalgae. The results demonstrate that coexposure to PS NPs and Cd2+ resulted in synergistic effects, including enhanced growth inhibition, photosynthetic impairment, membrane damage, and increased secretion of extracellular polymers. These findings highlight the increased ecological risks posed to aquatic organisms by the coexposure to PS NPs and Cd2+, emphasizing the need for comprehensive assessments of nanoplastic-pollutant interactions in aquatic ecosystems.

Metal-containing particles are the main component of the positive electrode in lithium-ion batteries (LIBs). However, the occurrence and behavior of these particles in wastewater remain inadequately understood. In this study, single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS) was employed to systematically track metal-containing particles in wastewater from a ternary precursor (TP) production facility and a full-scale wastewater treatment plant (WWTP). Multiple metal particles, including Ni-, Co-, Mn-, Al-, Cu-, and Zn-containing particles, were detected with size ranges of approximately 20-120 nm, 15-200 nm, 10-800 nm, 15-730 nm, 20-120 nm, and 25-925 nm, respectively. The above sentence in abstract should be revised as: Multiple metal particles, including nickel (Ni)-, cobalt (Co)-, manganese (Mn)-, aluminum (Al)-, copper (Cu)-, and zinc (Zn)-containing particles, were detected with size ranges of approximately 20-120 nm, 15-200 nm, 10-800 nm, 15-730 nm, 20-120 nm, and 25-925 nm, respectively. Characterization using transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy (TEM-EDS) revealed that these particles consisted of multiple metals and were partly in an agglomerated state. Further analysis demonstrated that the metal-containing particles showed metal-specificity in their dynamic transfer and transformation. Whereas Ni-, Co-, and Al-containing particles exhibited significant size variations, Mn-, Cu-, and Zn-containing particles showed little change. The particle number concentration decreased for Mn, Al, and Zn, increased for Co and Cu, while it remained stable for Ni. This study provides critical insights for improving treatment and management strategies of metal-containing particles in wastewater.

Elevated temperature reshapes physiological processes in aquatic ectotherms, yet how warming influences metal retention and clearance remains insufficiently resolved in fish. Here, we examined temperature-linked variation in tissue metal burdens in the demersal fish Chaeturichthys stigmatias. Across environmentally relevant temperature gradients, muscle concentrations of multiple metals declined with increasing temperature, with the strongest pattern observed for Pb. To explore mechanistic plausibility, we profiled Pb-associated protein fractions using SEC-ICP-MS and found that Pb-binding fractions were enriched for carbohydrate metabolism annotations, including glycolysis-related proteins. In parallel, metabolic perturbation assays indicated that cellular Pb accumulation was sensitive to metabolic state: Higher glucose availability coincided with lower intracellular Pb, and pharmacological disruption of glycolytic input increased Pb retention under low-glucose conditions, whereas mitochondrial uncoupling showed limited effects. Together, these results support a working model in which warming-enhanced metabolic turnover and glycolysis-linked processes may contribute to Pb handling, potentially involving reactive carbonyl/thiol chemistry and metal-metabolite interactions, rather than reliance on mitochondrial ATP alone. Our findings highlight a temperature-metabolism-metal axis that may alter contaminant fate in warming-impacted coastal systems and underscore the need to incorporate thermal context when interpreting biomonitoring data and assessing metal risk.

Atmospheric water inputs such as dew are often overlooked in plant biology. We show that foliar dewdrops act as biochemical microreactors that trigger flowering in Arabidopsis thaliana, a small plant from the mustard family (Brassicaceae). These droplets generate reactive oxygen species that induce intracellular nitric oxide accumulation, initiating a redox cascade that suppresses the biosynthesis of abscisic acid, which contributes to the regulation of flowering time. This occurs via S- nitrosylation- mediated activation of histone deacetylase 19, which silences AAO3 and ABA2. Analysis of over 12 million field records across the Brassicaceae family reveals a global correlation between dew point temperature and flowering time. These findings identify dewdrop chemistry as an unrecognized environmental cue that regulates developmental timing in plants.

Hg(II) reduction is a key process in regulating air-water exchange of Hg and its methylation. Dissolved organic matter (DOM) is an important factor in the photoreduction of Hg(II), yet the underlying mechanisms, particularly the involvement of superoxide, remain poorly understood. Herein, the contributions of dark and photochemical processes to reduction of Hg(II) were distinguished in surface waters (seawater and freshwater) based on measurements of purgeable Hg(0) using a purging-gold trap-cold vapor atomic fluorescence spectrometer, highlighting the importance of DOM in Hg(II) reduction. In surface waters, superoxide contributions to photoreduction were quantified, accounted for 38-55 % of DOM-mediated Hg(II) reduction for newly introduced Hg(II) and 28-33 % for pre-equilibrated Hg(II). Using Suwannee River Fulvic Acid Standard as a DOM model, we further confirmed that Hg(II) reduction was suppressed by the superoxide scavenger, with dissolved O2 significantly enhancing Hg(II) reduction. For newly introduced Hg(II), superoxide accounted for 29 % and 58 % of the total reduction under dark and light conditions, respectively, whereas its contribution decreased to 22 % and 37 % for pre-equilibrated Hg(II). Superoxide generation by seven DOM samples was quantified using 3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide as a probe. Phenolic OH-blocked DOM significantly inhibited superoxide generation by 76 %, which consequently resulted in approximately 80 % inhibition of Hg(II) reduction. These findings underscore the importance of phenolic-OH and superoxide in DOM-mediated dark/light reduction of Hg(II) and provide a deeper insight into Hg(II) reduction in diverse aerobic environments.

Photochemical methylation of mercury (Hg) is difficult to isolate in nature. Here we show that short-wavelength UV-C (254 nm) selectively drives aqueous Hg(II)→MeHg photomethylation in the presence of low-molecular-weight organic compounds with different methyl group (acetone, acetic acid, acetaldehyde), whereas no MeHg forms under visible/UV-A/UV-B light. Gross 4-h yields reach 59-84 % (acetone), 25-40 % (acetic acid), and 38-66 % (acetaldehyde). Coupled concentration-isotope time series resolve large odd-mass-independent fractionation (odd-MIF; Δ199Hg up to 25 ‰) with donor-specific Δ199Hg/Δ201Hg slopes. Acetone and acetic acid experiments display odd-only MIF with slopes of 0.9-1.0 and 1.1-1.3, consistent with magnetic isotope effects and a dominant role of radical-pair chemistry. By contrast, acetaldehyde experiment exhibits steeper slopes (1.8-2.0) accompanied by small negative Δ200Hg (down to -0.4 ‰), indicating complex mechanisms possibly related to multi-step electron transfer/heterogeneous processes. A reversible two‑pool isotopologue model recovers apparent forward and reverse rates and MDF enrichment factors, and reveals contrasting MDF partitioning: demethylation dominates in acetone, whereas methylation dominates in acetic acid. These methyl group donor-resolved isotope fingerprints identify a short wavelength photochemical route to MeHg and represent actional diagnostics for evaluating whether similar processes occur in atmospheric waters exposed to short wavelength radiation.

BACKGROUND:Ambient mass spectrometry, such as desorption electrospray ionization mass spectrometry (DESI-MS), represent a promising high-throughput platform for biomarkers analysis in biospecimens. However, its application to clinical biomarker analysis in biofluids remains limited by inherent trade-offs among sample preparation complexity, quantitative accuracy, and analytical reproducibility. RESULTS:In this study, we report, for the first time, the fabrication of a custom-designed target plate, using three-dimensional (3D) printing technology, to enable nanodroplet array preparation for high-throughput DESI-MS analysis. A single square target plate (2 mm × 2 mm) can accommodate 188 discrete 80-nL biofluid droplets, permitting high-throughput biomarker screening in biofluids with DESI-MS. For three clinically relevant renal function biomarkers, creatinine (Cr), urea nitrogen (UN), and uric acid (UA), the limits of detection (LODs) achieved with DESI-MS range from 0.1 to 0.8 μmol/L, an approximately tenfold improvement over conventional colorimetric enzymatic assays routinely employed in clinical laboratories. More critically, DESI-MS analysis of each individual urine or serum sample requires only 6.5 s, substantially shorter than the several minutes typically needed per sample for enzymatic methods. Finally, the feasibility, reliability, and reproducibility of the developed method were demonstrated through quantifying Cr, UN, and UA in serum and urine samples from mice exposed to inorganic mercury (Hg(II)), serving as a proof-of-concept validation. SIGNIFICANCE:We anticipate that this robust strategy for biofluid analysis will advance both biomarker discovery and mechanistic studies across clinical medicine, biology, and environmental health science.

RATIONALE:As quadrupole and ion trap mass analyzers are miniaturized toward millimeter scales, fabrication quality increasingly constrains analytical performance. Micrometer-scale deviations in electrode geometry, surface finish, and assembly alignment can introduce higher order multipole fields, thereby degrading resolution, sensitivity, and ion transmission. Conventional precision machining and sequential assembly therefore face increasing difficulty in simultaneously achieving field fidelity, geometric complexity, and scalable integration. METHODS:This narrative review compares conventional subtractive manufacturing with four advanced routes: microelectromechanical systems (MEMS), low-temperature co-fired ceramics (LTCC), additive manufacturing (AM), and printed-circuit-board (PCB)-based architectures. A process-problem-performance framework is used to link each process to the error modes it mitigates or introduces and to the analytical performance affected. RESULTS:MEMS provides high planar registration but remains limited in forming true 3D electrode surfaces. LTCC reduces assembly burden and supports multilayer integration but is constrained by shrinkage and feature resolution. AM offers monolithic 3D freedom, although electrode-grade performance requires surface engineering, metallization, and control of dielectric and vacuum-related effects. PCB-based architectures enable rapid prototyping and field synthesis but usually lack field-critical geometric precision. Across these routes, no single technology simultaneously maximizes fabrication precision, geometric freedom, and scalable integration. CONCLUSIONS:Hybrid manufacturing strategies that allocate field-critical, structural, interconnect, packaging, and calibration functions to complementary processes represent the most practical route toward reproducible next-generation quadrupole and ion trap mass analyzers. Future progress will depend on standardized comparisons of fabrication tolerance, surface quality, RF compatibility, material stability, and demonstrated analytical performance.

Natural metal-containing nanoparticles (NMNs) represent a distinct and ubiquitous form of metals in the environment, characterized by reactivity intermediate between soluble ions/complexes and relatively inert macroscopic materials. This review uniquely synthesizes how the intrinsic nanoparticles properties enable NMNs to function as key transport vectors in the environment and unconventional carriers into organisms, roles systematically overlooked in existing models. Special emphasis is placed on aquatic systems, where NMNs exhibit intensified mobility and transformation through colloidal processes. As stabilized colloids, NMNs' nanoscale size and organic-matter-induced stabilization enable prolonged suspension and long‑distance transport of metals in aquatic systems. Furthermore, through colloidal migration and adsorption and transformation involving dissolved ions and larger particles, NMNs regulate metal transport in porous media via mechanisms fundamentally different from dissolved ions and macroparticles. Biologically, NMNs enter organisms via pathways like the "Trojan horse" mechanism, resulting in cellular uptake, distribution, and toxicity profiles different from those of metal ions, which is not included in current models (e.g., biotic ligand model). By synthesizing these insights and identifying future research priorities, this review lays a foundation for incorporating the NMNs forms into models, advancing toward a more predictive and mechanistic framework for understanding metal fates and risks.