Airborne PET nanoplastics alter tobacco’s chemical risk

Atmospheric micro(nano)plastics (MNPs), including polyethylene terephthalate (PET), enter plants via leaves, accumulating in tissues. Foliar PET nanoplastic exposure alters Nicotiana benthamiana nicotine biosynthesis, favoring the more potent (S)-isomer even without growth inhibition. This accumulation reveals a contamination pathway for combustible consumer products, demonstrating that MNPs-induced alteration of a plant’s endogenous biochemistry represents a significant and previously uncharacterized risk to agricultural sustainability and human health.