Research Repository

Phytotoxicity of silver nanoparticles on Vicia faba: evaluation of particle size effects on photosynthetic performance and leaf gas exchange

Falco, William F and Scherer, Marisa D and Oliveira, Samuel L and Wender, Heberton and Colbeck, Ian and Lawson, Tracy and Caires, Anderson RL (2020) 'Phytotoxicity of silver nanoparticles on Vicia faba: evaluation of particle size effects on photosynthetic performance and leaf gas exchange.' Science of the Total Environment, 701. ISSN 0048-9697

[img] Text
2020-STOTEN.pdf - Accepted Version
Restricted to Repository staff only until 5 October 2020.
Available under License Creative Commons Attribution Non-commercial No Derivatives.

Download (1MB) | Request a copy

Abstract

Nanotechnology is an emerging field in science and engineering, which presents significant impacts on the economy, society and the environment. The nanomaterials’ (NMs) production, use, and disposal is inevitably leading to their release into the environment where there are uncertainties about its fate, behaviour, and toxicity. Recent works have demonstrated that NMs can penetrate, translocate, and accumulate in plants. However, studies about the effects of the NMs on plants are still limited because most investigations are carried out in the initial stage of plant development. The present study aimed to evaluate and characterize the photochemical efficiency of photosystem II (PSII) of broad bean (Vicia faba) leaves when subjected to silver nanoparticles (AgNPs) with diameters of 20, 51, and 73 nm as well as to micrometer-size Ag particles (AgBulk). The AgNPs were characterized by transmission electron microscopy and dynamic light scattering. The analyses were performed by injecting the leaves with 100 mg L-1 aqueous solution of Ag and measuring the chlorophyll fluorescence imaging, gas exchange, thermal imaging, and reactive oxygen species (ROS) production. In addition, silver ion (Ag+) release from Ag particles was determined by dialysis. The results revealed that AgNPs induce a decrease in the photochemical efficiency of photosystem II (PSII) and an increase in the non-photochemical quenching. The data also revealed that AgNPs affected the stomatal conductance (gs) and CO2 assimilation. Further, AgNPs induced an overproduction of ROS in Vicia faba leaves. Finally, all observed effects were particle diameter-dependent, increasing with the reduction of AgNPs diameter and revealing that AgBulk caused only a small or no changes on plants. In summary, the results point out that AgNPs may negatively affect the photosynthesis process when accumulated in the leaves, and that the NPs themselves were mainly responsible since negligible Ag+ release was detected.

Item Type: Article
Uncontrolled Keywords: Vicia faba, Photosynthetic performance, Silver nanoparticle, Nanoparticle diameter effect, Toxicity
Divisions: Faculty of Science and Health > Life Sciences, School of
Depositing User: Elements
Date Deposited: 10 Oct 2019 10:18
Last Modified: 11 Nov 2019 10:15
URI: http://repository.essex.ac.uk/id/eprint/25586

Actions (login required)

View Item View Item