Fate and Transport Pathways of Microplastics in Agricultural Soil and their Interaction with Agrochemicals

Industrialization has driven a surge in plastic consumption, resulting in the accumulation of synthetic materials in ecosystems, which fragment into microplastics and further degrade into nanoplastics. Major sources include shedding synthetic fibers from clothing, tire abrasion, road markings, plastic pellets, and personal care products containing plastic scrubbers. Microplastics enter soil through atmospheric deposition, surface runoff, and the use of plastic-based agricultural materials like mulch and irrigation tubing. Trapped in soil pores, microplastics undergo degradation via mechanisms such as photo-oxidation, thermal degradation, ozone degradation, and biodegradation. Soil texture, organic matter content, and moisture influence their mobility. Microorganisms in soil interact with microplastics, potentially leading to aggregation, degradation, or bioaccumulation. Microplastics also adsorb contaminants like agrochemicals, posing complex environmental challenges by facilitating their transport, adsorption, and desorption, spreading within ecosystems. Techniques like phytoremediation, biodegradation, and microbial degradation can remove microplastics and associated agrochemical contaminants. Moreover, implementing best management practices in agriculture, including reducing agrochemical usage, adopting sustainable farming methods, and promoting responsible waste management, can mitigate the release of microplastics and agrochemicals into the environment. These strategies are crucial for addressing the multifaceted environmental impacts of microplastic pollution and promoting ecosystem health.