Absorption of microplastics by terrestrial plants and their ecological risk

Microplastics (MPs) are ubiquitous in the environment and pose widespread exposure risks to terrestrial plants. Recent studies have revealed that MPs in soil can migrate into plants via root systems, while atmospheric MPs can infiltrate plants through leaves. Plants are a primary component of food chains. Plant uptake and accumulation of MPs greatly determine their ecological and health risk. This review systematically introduces entry pathways of MPs into plants via roots and leaves, and their transport, distribution, and accumulation within plant tissues. The phytotoxicity of MPs, including both the direct physical damage induced by polymer particles, and the toxicity induced by additives such as plasticizers, antioxidants, and UV stabilizers, are discussed. Accordingly, the potential implications of MPs pollution for food security and risks of MPs transmission through food chains were analyzed. Furthermore, phytotoxicity risks mediated by MPs-induced alterations in microbial community structures were elucidated. Finally, the key unresolved questions in the research on plant uptake of MPs are summarized and promising future research directions are proposed.