Microplastic uptake and impacts on crops under realistic exposure: implications for soil-plant systems

Area of Science:

• Environmental Science
• Agricultural Science
• Ecotoxicology

Background:

• Micro- and nanoplastic (MNP) contamination poses risks to agroecosystems and food safety.
• Understanding MNP fate and effects under realistic conditions is crucial but lacking.

Purpose of the Study:

• To investigate MNP behavior, toxicity, and uptake in wheat and tomato under realistic soil conditions.
• To assess the impact of polymer type, size, concentration, and surface characteristics on MNP effects.

Main Methods:

• Studied aged polyethylene terephthalate (PET) fibers and polyethylene (PE) fragments in silty loam soil with wheat and tomato.
• Evaluated individual and mixed MNP exposures, plant-mediated retention, and MNP translocation.

Main Results:

• Plant presence reduced MNP leaching; smaller MNPs leached more than larger ones.
• Fibers were more toxic than fragments, reducing chlorophyll and growth, especially in tomato.
• Mixed MNP exposures showed synergistic phytotoxicity in tomato.
• Aged NPs were absorbed and translocated in plants; surface characteristics influenced uptake.

Conclusions:

• Realistic MNP exposure conditions reveal significant impacts on crop plants.
• Aged MNPs pose uptake and translocation risks, with surface properties being key.
• Findings underscore the need for MNP risk assessments reflecting real-world agricultural scenarios.