Beyond the surface: Microplastic pollution its hidden impact on insects and agriculture

Abstract

This study comprehensively investigates the impact of microplastic pollution on soil and plant health, focusing on the test organism S. frugiperda and maize crops. Various plastics were integrated into the soil at different concentrations, with continuous monitoring of soil parameters revealing nuanced effects on soil physicochemical properties. Leaf area consumed by S. frugiperda caterpillars was meticulously quantified, elucidating the influence of plastic treatments on plant susceptibility to herbivory. Fourier Transformed Infrared (FTIR) analysis provided insights into the presence of hydrocarbon-based polymers, while Environmental Scanning Electron Microscopy (ESEM) analysis highlighted the pervasive distribution of microplastics within plant samples. Rigorous methodologies, including controlled extraction and chemical digestion, identified microplastics in plant and insect samples, emphasizing their potential transmission from soil to plants and insects. Advanced analytical techniques such as FTIR and ESEM characterized microplastics' polymer types and properties. The study contributes insights into the nuanced relationship between microplastics and insects, exploring their hormetic effects on insect populations and potential synergies with additives and environmental contaminants. Findings reveal microplastic concentrations in plant samples ranging from 10 μm to 100 μm, with prevalent polymers being Polyethylene (PE) and Polypropylene (PP). Detailed soil analysis underscores microplastics' adverse effects on soil physical, chemical properties, and nutrient status, informing strategies for mitigating plastic pollution and safeguarding environmental and agricultural sustainability through evidence-based policymaking and interdisciplinary collaboration.