Toxicity, Uptake, and Translocation of Engineered Nanomaterials in Vascular plants

Abstract

To exploit the promised benefits of engineered nanomaterials, it is necessary to improve our knowledge of their bioavailability and toxicity. The interactions between engineered nanomaterials and vascular plants are of particular concern, as plants closely interact with soil, water, and the atmosphere, and constitute one of the main routes of exposure for higher species, i.e. accumulation through the food chain. A review of the current literature shows contradictory evidence on the phytotoxicity of engineered nanomaterials. The mechanisms by which engineered nanomaterials penetrate plants are not well understood, and further research on their interactions with vascular plants is required to enable the field of phytotoxicology to keep pace with that of nanotechnology, the rapid evolution of which constantly produces new materials and applications that accelerate the environmental release of nanomaterials.

Determination of zinc oxide nanoparticles toxicity in root growth in wheat (Triticum aestivumL.) seedlings

“…As plants are the essential base component of the ecosystems, and being sessile organisms, they play an important role to assess the effects of ENPs in the environment [22,34]. In plants, root growth is characterized by high metabolic activity and alteration or inhibition occurs as a result of abiotic stresses such as exposure to excess trace elements [24].…”

Interactions between engineered nanomaterials and agricultural crops: implications for food safety

“…For example, multi-wall carbon nanotubes (MWCNTs) and C 70 fullerene were stabilized in natural organic matter (NOM, including humic acid) and gum Arabic solutions in the media (Lin et al, 2009;Larue et al, 2012b); metal-based ENMs such as Fe 3 O 4 , Au, Ag, and Ni(OH) 2 were coated with citrate, tannate, or polyvinylpyrrolidone (PVP) (Parsons et al, 2010;Wang H. et al, 2011;Judy et al, 2012a;Lee et al, 2012). There are also reports using agar or semi-solid media such as Murashige and Skoog (MS) medium that may be amended with ENMs prior to solidification (Lee et al, 2008;Miralles et al, 2012b;Yang et al, 2012;Yan et al, 2013). In either agar or aqueous systems, biocompatible agents such as humic acid are preferable due to greater environmental relevance and less potential toxicity than synthetic surfactants such as sodium dodecyl sulfate (SDS) or PVP.…”

“…It has been proposed that cell internalization of ENMs could occur by binding to carrier proteins, through aquaporins, ion channels, endocytosis, or by creating new pores (carbon nanotubes) (Rico et al, 2011). While experimental data are scarce and many proposed mechanisms are under intense debate, endocytosis has been demonstrated definitively through the use of temperature control and the addition of endocytosisinhibiting agents such as wortmannin (Onelli et al, 2008;Liu et al, 2009;Iversen et al, 2012;Miralles et al, 2012b). Enhanced expression of aquaporin proteins and up-regulation of water channel genes were found to support possible passive uptake mechanisms (Khodakovskaya et al, 2012).…”

Effect of Concentration of Silver Nanoparticles on the Uptake of Silver from Silver Nanoparticles in Soil

“…Ag NPs are introduced into the terrestrial systems primarily through applications of sewage sludge to land [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Once present in an ecosystem, the environmental behavior, fate and ecotoxicity of metal-based nanoparticles are known to be influenced by their physical and chemical characteristics.…”

“…It has long been established that some plants are able to uptake metals from soil via the roots and distribute them throughout the shoot system [53,23,8,54]. A possible explanation for the differences in translocation may be due to the differences in root exudates.…”