Occurrence of microplastics in terrestrial habitats: Hazards and pollution abatement

Abstract

Microplastics (MPs) are ubiquitous and pose an environmental risk. This review examined MP pollution in terrestrial ecosystems from a myriad of poorly understood sources. Knowledge regarding the occurrence sources, migration behaviors, ecotoxicology, absorption mechanisms, and effects of MPs has also been fully summarized. Microplastics interact with contaminants, such as antibiotics, pesticides, heavy metals, etc., and may act as vectors for contaminant transfer in terrestrial ecosystems. The transportation and retention of MPs in soil are governed by interactions among their inherent properties, such as size, shape, surface charge, and density. Interestingly, MP migration into soil is lacking research. The MPs and nanoplastics were also found in edible fruits and vegetables. The MP contamination in soil affects ecosystems, causing soil structure changes, fertility reduction, and pollutant leaching into groundwater. The MP concentration lies in the range of 43–2 443 and 40–43 000 items kg-1 in agricultural and urban soils, respectively. This review provides a comprehensive roadmap for future research and a framework for soil MP risk assessment. Future studies on the uptake, accumulation, and translocation of MPs and their associated toxins by plants are essential for evaluating their risks to food security and human health. Research on MPs in terrestrial habitats lacks comprehensive data on their long-term persistence, degradation pathways, and interactions with soil components under varying environmental conditions. Additionally, limited understanding exists regarding MP impacts on soil biodiversity, pollutant mobility, and plant uptake, highlighting the need for innovative detection methods and effective pollution abatement strategies.