Fate of pristine TiO2 nanoparticles and aged paint-containing TiO2 nanoparticles in lettuce crop after foliar exposure.
Engineered TiO2 nanoparticles (TiO2-NPs) are present in a large variety of consumer products, and are produced in largest amount. The building industry is a major sector using TiO2-NPs, especially in paints. The fate of NPs after their release in the environment is still largely unknown, and their possible transfer in plants and subsequent impacts have not been studied in detail. The foliar transfer pathway is even less understood than the root pathway. In this study, lettuces were exposed to pristine TiO2-NPs and aged paint leachate containing TiO2-NPs and microparticles (TiO2-MPs). Internalization and in situ speciation of Ti were investigated by a combination of microscopic and spectroscopic techniques. Not only TiO2-NPs pristine and from aged paints, but also TiO2-MPs were internalized in lettuce leaves, and observed in all types of tissues. No change in speciation was noticed, but an organic coating of TiO2-NPs is likely. Phytotoxicity markers were tested for plants exposed to pristine TiO2-NPs. No acute phytotoxicity was observed; variations were only observed in glutathione and phytochelatin levels but remained low as compared to typical values. These results obtained on the foliar uptake mechanisms of nano- and microparticles are important in the perspective of risk assessment of atmospheric contaminations.
ISTerre, Université de Grenoble 1, CNRS, 38041 Grenoble, France. Electronic address: camille.larue@rub.de.
Camille
C
Larue
European Synchrotron Radiation Facility, Beamline ID21, Grenoble, France. Electronic address: castillo@esrf.fr.
Hiram
H
Castillo-Michel
Laboratoire de Spectrochimie Infra Rouge et Raman, UMR CNRS 8516, Université Lille 1, Bât C5, 59655 Villeneuve d'Ascq Cedex, France. Electronic address: sophie.sobanska@univ-lille1.fr.
Sophie
S
Sobanska
Synchrotron SOLEIL, Gif-sur-Yvette 91192, France. Electronic address: nicolas.trcera@synchrotron-soleil.fr.
Nicolas
N
Trcera
Université Bordeaux 1, CNRS/IN2P3, Centre d'Etudes Nucléaires de Bordeaux Gradignan, CENBG, Chemin du Solarium, BP120, 33175 Gradignan, France. Electronic address: sorieul@cenbg.in2p3.fr.
Stéphanie
S
Sorieul
ISTerre, Université de Grenoble 1, CNRS, 38041 Grenoble, France. Electronic address: lauric.cecillon@irstea.fr.
Lauric
L
Cécillon
Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux (LCABIE/IPREM-UMR 5254), Université de Pau et des Pays de l'Adour, Hélioparc, 2 Av. Pierre Angot, 64053 Pau Cedex 9, France. Electronic address: laurent.ouerdane@univ-pau.fr.
Laurent
L
Ouerdane
CEA/LITEN/DTNM/L2T, CEA Grenoble, Av des Martyrs, 38054 Grenoble Cedex 9, France. Electronic address: samuel.legros@cea.fr.
Samuel
S
Legros
ISTerre, Université de Grenoble 1, CNRS, 38041 Grenoble, France. Electronic address: geraldine.sarret@ujf-grenoble.fr.
Géraldine
G
Sarret
D004396:Coloring Agents / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D018545:Lactuca / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles; D010150:Paint; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D010940:Plant Proteins / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014025:Titanium / Q000494:pharmacology*
D004396:Coloring Agents; D010940:Plant Proteins; D017392:Thiobarbituric Acid Reactive Substances; C009495:titanium dioxide; D014025:Titanium; D005978:Glutathione
Ecotoxicology; Micro-XAS; Micro-XRF; Plant; TiO(2) nanoparticle