Barriers, pathways and processes for uptake, translocation and accumulation of nanomaterials in plants--Critical review.

Published

Journal Article (Review)

Uptake, transport and toxicity of engineered nanomaterials (ENMs) into plant cells are complex processes that are currently still not well understood. Parts of this problem are the multifaceted plant anatomy, and analytical challenges to visualize and quantify ENMs in plants. We critically reviewed the currently known ENM uptake, translocation, and accumulation processes in plants. A vast number of studies showed uptake, clogging, or translocation in the apoplast of plants, most notably of nanoparticles with diameters much larger than the commonly assumed size exclusion limit of the cell walls of ∼5-20 nm. Plants that tended to translocate less ENMs were those with low transpiration, drought-tolerance, tough cell wall architecture, and tall growth. In the absence of toxicity, accumulation was often linearly proportional to exposure concentration. Further important factors strongly affecting ENM internalization are the cell wall composition, mucilage, symbiotic microorganisms (mycorrhiza), the absence of a cuticle (submerged plants) and stomata aperture. Mostly unexplored are the roles of root hairs, leaf repellency, pit membrane porosity, xylem segmentation, wounding, lateral roots, nodes, the Casparian band, hydathodes, lenticels and trichomes. The next steps towards a realistic risk assessment of nanoparticles in plants are to measure ENM uptake rates, the size exclusion limit of the apoplast and to unravel plant physiological features favoring uptake.

Full Text

Duke Authors

Cited Authors

  • Schwab, F; Zhai, G; Kern, M; Turner, A; Schnoor, JL; Wiesner, MR

Published Date

  • January 2016

Published In

Volume / Issue

  • 10 / 3

Start / End Page

  • 257 - 278

PubMed ID

  • 26067571

Pubmed Central ID

  • 26067571

Electronic International Standard Serial Number (EISSN)

  • 1743-5404

International Standard Serial Number (ISSN)

  • 1743-5390

Digital Object Identifier (DOI)

  • 10.3109/17435390.2015.1048326

Language

  • eng