The transport and retention behavior of microplastics (MPs) in saturated porous media is a hot issue in the fields of ecological security and public health in contemporary society. In this study, the transport and retention behaviors of polystyrene microplastics (PS-MPs) in saturated porous media were systematically investigated under various environmental conditions, including humic acid (HA) concentration, ionic strength (IS), mass fraction of iron oxyhydroxide coated quartz sand (ω), and pH in the presence of HA. A series of column experiments were conducted, and all breakthrough curves and retention profiles were successfully simulated using a two kinetic sites attachment-detachment model (TKSADM) that distinguishes between chemical adsorption (Site 1) and physical retention (Site 2). Results demonstrated that increasing HA concentration from 1 to 10 mg L⁻¹ enhanced PS-MP transport, which was attributed to HA adsorption creating steric hindrance and enhancing electrostatic repulsion. In contrast, HA conditions, increasing IS from 0.1 to 100 mM progressively suppressed MP transport, with model parameters revealing a dramatic 30-fold increase in physical retention rate (k_att2) and a 2.8-fold increase in chemical adsorption capacity (S_max1/C₀), reflecting the dual role of IS in compressing the electrical double layer and inducing HA conformational collapse. Increasing the mass fraction of iron oxyhydroxide coated quartz sand (ω from 0.15 to 0.75) substantially inhibited PS-MP transferability, with both chemical adsorption rate (k_att1) and physical retention rate (k_att2) increasing by 57% and 83%, respectively, accompanied by a 79% increase in S_max1/C₀. This balanced enhancement reflects the dual role of iron oxyhydroxide coatings: increased surface roughness creating physical straining sites and Fe–OH groups providing abundant reactive sites for specific adsorption. Increasing pH from 6.0 to 10.0 substantially enhanced MP mobility, with all retention – related parameters decreasing monotonically: k_att1 decreased by 34%, k_att2 decreased by 52%, and S_max1/C₀ exhibited the most dramatic decline (71%), revealing a “pH-switching effect” on physical retention sites – activated at low pH and deactivated at high pH due to enhanced electrostatic repulsion and HA conformational extension. This study provides quantitative mechanistic insights into MP fate in subsurface environments and underscores the need to consider coupled effects of multiple environmental factors when predicting MP transport behavior.

Medical chemistry serves as an indispensable bridge connecting foundational chemical sciences with clinical medicine, yet traditional discipline-based teaching models create a persistent gap between chemical principles and clinical practice. This narrative review establishes a five-dimensional analytical framework—driving forces, curriculum restructuring, pedagogical innovation, practical translation, and outcome evaluation—developed from the multidisciplinary-interdisciplinary-transdisciplinary integration continuum, competency-based medical education theory, and constructive alignment principles. The framework, with the traditional discipline-based teaching model as the comparison baseline, is applied to systematically examine 105 studies from 2016 to 2025, identified through a reproducible search protocol across PubMed, Web of Science, Scopus, ERIC, and CNKI. The analysis reveals a progressive evolution from knowledge-service to competency-construction paradigms across multiple national contexts. Curriculum restructuring has advanced through a complementary three-stage trajectory, with clinical-topic spiral modules demonstrating superior knowledge transfer in settings with established cross-disciplinary faculty collaboration. Pedagogical innovation has achieved contrastive complementarity between case-based and problem-based learning, supported by Bayesian network meta-analysis evidence, though reported effect sizes are moderated by implementation fidelity, class size, and assessment alignment. Experimental teaching reform has progressed along a four-stage trajectory toward interdisciplinary innovative experiments, with virtual simulation addressing infrastructure constraints in resource-limited settings. A multi-level assessment framework, operationalized through an instrument-outcome matrix linking knowledge, clinical reasoning, practical skills, and long-term outcomes, is proposed to replace the current fragmented evaluation landscape. Three persistent bottlenecks—cross-disciplinary faculty development, resource integration mechanisms, and evaluation standard unification—constrain further progress. The review's findings are framed with appropriate caution, acknowledging the predominance of single-center small-sample studies that limit generalizability, and recognizing that high-quality educational research can employ diverse methodologies beyond randomized controlled trials.