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ABSTRACT Microplastics have received increased attention due to their negative impacts on the environment and human health. To minimize these impacts, mitigation strategies that are efficient and cost‐effective for a range of plausible conditions need to be developed. Models can be used to support these mitigation‐related decisions. However, modeling studies related to the export of microplastics from terrestrial to aquatic systems have been limited. Here, we review such modeling studies, the trends over time and geography of focus, and discuss pertinent concepts and the underlying physical, chemical, and biological processes. We categorize the published modeling studies, discuss their limitations, and provide recommendations for future research to fill key knowledge gaps. Future modeling efforts should focus on collecting more comprehensive field data for validation, developing continuous models over event‐based, conducting experimental studies to better understand the fundamental processes, developing hybrid modeling frameworks, adopting sediment transport modeling approaches, incorporating land management practices in the models, integrating surface and sub‐surface processes at the watershed scale, and utilizing advanced data‐driven models like foundation models. 

Abstract This study presents the development of an innovative nanofibrous membrane to remove microplastics (MPs) from drinking water. This membrane exhibits additional functionality in removing lead (Pb), highlighting its promising potential for utilization as a point‐of‐use (POU) device. The polyvinyl alcohol (PVA) nanofibrous membranes are crosslinked using glutaraldehyde, and their efficiencies in the removal of MPs are evaluated. The results show that crosslinking the 7 and 10 wt% PVA nanofibers increases their average diameters to 330 and 581 nm, respectively, and enhances their surface area. The treatment efficiency of crosslinked PVA fibrous media is evaluated using polyethylene (PE) (5 μm ≤d ≤ 25 μm) and polystyrene (PS) MPs (d ≤ 1 μm). The filtration efficiencies of both 7 and 10 wt% c‐PVA nanofibrous media are found to be 99.8% ± 0.1% in the removal of PE MPs at pH 8. Further examination of the filtration efficiency in the removal of PS MPs shows that the highest removal efficiency achieved was 77.3% ± 1.4% at a pH of 6. Additionally, the lead removal efficiency of this fibrous membrane in flow‐through experiments is examined. Results show a pH‐dependent lead removal efficiency, in which the greatest efficiency of 69% is found at pH 6. 

Abstract The application of agricultural plastic products such as mulch, greenhouse covers, and silage films is increasing due to their economic benefits in providing an early and better‐quality harvest. However, mechanical abrasion of these plastic materials by soil particles could result in generation of microplastic (MP) pollutants that could harm soil organisms and impact food safety. This study aims to better understand the physicochemical mechanisms resulting in the fragmentation of low‐density polyethylene (LDPE). Herein, we used pellets and films to study the impacts of abrasive wear forces on their surface morphology variations and fragmentation behavior. An innovative laboratory approach was developed to abrade the plastic surface under controlled normal loadings and abrasion durations. The investigation of the plastics’ surface morphology variations due to the abrasion process revealed microcutting as the dominant process at low normal force (4 N). However, a combination of microploughing and microcutting occurred for new LDPE films by increasing the normal force to 8 N. Despite the significant surface morphology variations of the new LDPE film due to the abrasion process; the water contact angle did not alter. Furthermore, the fragmentation behavior of photodegraded LDPE pellets and films was compared to the new plastics. The extent of MPs (3 µm < d_p < 162 µm) generation due to fragmentation was studied using fluorescence microscopy imaging. The localized stress and strains at the contact sites of plastic and sand particles resulted in abrasion of the plastic surface. According to the results, the normal loadings and duration of abrasion played a significant role in the degree of fragmentation of plastics. Increasing the normal loading applied during the abrasion process from 2 to 8 N linearly increased the number of generated plastic fragments by more than five times for pellets and more than three times for film. Photodegradation significantly enhanced the extent of MPs fragmentation. Moreover, the limitations of this study and the implications for agricultural soil health were discussed.