Microplastics as Emerging Contaminants: Unraveling Their Impact on Soil Health

Microplastics (MPs), plastic particles smaller than 5 mm, are pervasive pollutants contaminating food, water, and air. Originating from industrial processes, agricultural practices, and plastic degradation, they infiltrate aquatic and terrestrial ecosystems, including soils. In soil, pose significant environmental risks by altering physical, chemical, and biological properties. Physically, they disrupt soil structure, reducing porosity, water retention, and aeration, which hinders root growth and water uptake. Chemically, MPs interact with soil constituents, serving as carriers for toxic substances like pesticides and heavy metals while releasing harmful additives that alter soil chemistry. Biologically, they affect microbial communities, decreasing diversity, enzyme activity, and nutrient cycling, ultimately diminishing soil fertility and productivity. These changes have severe ecological and agricultural consequences. MPs can migrate into plants and enter the food chain, potentially affecting human health. Altered soil properties may reduce crop yields, threatening food security. Their persistence exacerbates long-term environmental impacts, while sorbed toxic substances further endanger organisms. Addressing microplastic pollution is critical to safeguarding soil health, ecosystem balance, and sustainable agriculture. This review examines the sources, types, and behavior of MPs in soil, along with their impact on soil health and productivity, emphasizing the urgency of mitigating this growing threat.