Impact of microplastics on growth, photosynthesis and essential elements in Cucurbita pepo L

• Published in: Journal of hazardous materials 2022-02, Vol.423 (Pt B), p.127238-127238, Article 127238
• Main Authors: Colzi, Ilaria, Renna, Luciana, Bianchi, Elisabetta, Castellani, Maria Beatrice, Coppi, Andrea, Pignattelli, Sara, Loppi, Stefano, Gonnelli, Cristina
• Format: Article
• Language: English
• Subjects: Chlorophyll; Chlorophyll fluorescence; Cucurbita; Ionome; Leaf traits; Microplastic toxicity; Microplastics; Photosynthesis; Plastics - toxicity; Zucchini
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.127238

In this study, Cucurbita pepo L., one of the most cultivated, consumed and economically important crop worldwide, was used as model plant to test the toxic effects of the four most abundant microplastics identified in contaminated soils, i.e. polypropylene (PP), polyethylene (PE), polyvinylchloride (PVC), and polyethyleneterephthalate (PET). Cucurbita plants were grown in pots with increasing concentrations of the microplastics, then plant biometry, photosynthetic parameters and ionome of treated vs. untreated samples were compared to evaluate the toxicity of each plastic. All the pollutants impaired root and, especially, shoot growth. Specific and concentration-dependant effects of the different microplastics were found, including reduction in leaf size, chlorophyll content and photosynthetic efficiency, as well as changes in the micro- and macro-elemental profile. Among all the microplastics, PVC was identified as the most toxic and PE as the less toxic material. PVC decreased the dimensions of the leaf lamina, the values of the photosynthetic performance index and the plant iron concentration to a higher extent in respect to the other treatments. Microplastic toxicity exerted on the growth of C. pepo raises concerns about possible yield and economic loss, as well as for risks of a possible transfer into the food chain. [Display omitted] •Toxic effects of microplastics PP, PE, PVC, and PET were tested on Cucurbita pepo.•Microplastics exerted specific type- and concentration-dependent effects.•Biometry, photosynthetic parameters and ionome were altered by microplastic treatment.•PVC was the most toxic microplastic for Cucurbita pepo whereas PE the less toxic one.