Nanomatériaux et nanoparticules manufacturées : Risques environnementaux / Jean ‐ Yves Bottero, and Mélanie Auffan, Jérôme Rose, Céline Botta, Jérôme Labille, Armand Masion, N Solovitch ‐ Vella, E.M Hotze And the US and French members of the GDR ‐ I Consortium for the Environmental Implications of Nano Technology IRSN 21 Septembre 2010
Quelques chiffres: Nombre de produits répertoriés en 2009 Source: Program Emerging Nanotechnology En 2010: plus de 2000 Source Nanowerk
Catégories
Dans le domaine dit « du bien être »
Les éléments les plus présents From Ch Robichaud PhD DUKE Univ Decembre 2010
Understanding AgNPs formation/ transformation in wastewater treatment Targeted National Sewage sludge Survey Statistical Analysis Report (Released in Jan 2009) � 74 plants across the States � Total metal contents � Pharmaceuticals, steroids, and hormones Sludge ID 68349 (from Midwest region) Elemental Analysis (mg kg -1 ) Element Mg 13500 Ag 856 Mn 1070 Al 57300 Na 6080 Ca 98900 P 57200 Cu 1720 Ti 4510 Fe 51000 Zn 1530 Blaser, S. A. et al., Science of the Total Environment (2008).
Spécificités extrinsèques des nanos: Relations taille, nombre, surface
Specifities « intrinèsques » des Nanos Tout n’est pas NANO ! 1 NP < 30 nm méritent une considération spéciale en écotoxicité… ? 30 nm Strong surface reactivity Strong increase of the < 30 nm surface atom number M.Auffan et al., NATURE nano, 09- 2009
Environmental behavior and (eco)toxicity • Trophic transfer via A terrestrial A marine food chain food chain food webs Quaternary consumers Hawk Killer whale Tertiary consumers Snake Cod Secondary consumers Mouse Herring Transformation? Primary consumers Grasshoper Zooplancton Producers Flowers Phytoplancton bacterias.. http://www.pearsonsuccessnet.com/iText/products/0 ‐ 13 ‐ 115075 ‐ 8/text/chapter36/concept36.1.html
Before bioavailability: A-Transformation from B-transfer I o n i c s t products: speciation, r e n g diffusion t h coagulation p H surface properties and Inorganic stability colloïds III. D-Biodegradation bioavailability Toxicity Organic molecules pollutants diffusion C-Interaction with Biofilms matter floculation
A- Transformation Ex 1:Fate of C60 fullerenes in water from hydrophobic to hydrophilic material stirring n o i t a g u f r i t n e c a r t l u stable dispersion of nanometric crystallites (nC60)
Evidence of C60 hydrophilic character gravimetric measurement of H 2 O vapour adsorption at 30°C, and ambient pressure 10 number of H 2 O monolayers adsorbed 9 8 H 2 O 7 6 C60 fullerite 5 4 stirring 3 2 1 0 0 0.2 0.4 0.6 0.8 1 P (H 2 O) / P 0 Previous outgassing (110°C, 18h) multi ‐ layer adsorption of H 2 O irreversible modification of the surface Brant et al., 2007 JCIS Labille et al., 2006 Fullerenes Nanotubes and Carbon Nanostructures Labile et al., 2009, Langmuir, in press
Chemical characterisation of AQU/nC60s FTIR 0.6 C ‐ OH nC60 pure C60 H 2 O 0.4 H 2 O CO ‐ H Absorbance 0.2 1H SS NMR 0.0 fullerol 4000 3000 2000 1000 -1 ) Wave number (cm hydroxylation of the nC60 surface gives AQU/nC60 hydrophilic surface C60 14 12 10 8 6 4 2 0 -2 -4 ppm Labille et al., langmuir, in press 2009
Ex 2: Case of Titanium dioxide-based nanocomposite • Nano ‐ TiO2 in sunscreen CH 3 PDMS Si O PDMS AlOOH n CH 3 50 nm 14-16 nm AlOOH TiO 2 TiO 2 Leaching of the surface layers may UV lead to a direct contact between TiO 2 water and TiO2. TiO2 can then generate ROS ( O 2 • O 2 - OH •) O 2 O 2 OH • • - J Labille et al (Env Pollution) 2010 and M Auffan et al, ES and T et al, ES and T 2010
UV alteration of PDMS coating ?
B ‐ Transfert and diffusion in porous media Case of TiO2 in sand Case of Nano Ag° 0.6 NaCl 0.5 CaCl2 attachment coefficient NaCl + gellan 0.4 NaCl + A. tannic 0.3 0.2 0.1 0 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00 Sand Sand and FeOOH salt concentration (mol/L) N Solovitch et al, Environmental Science Shihong Lin et al , Duke And Technology 2010
C ‐ Effect of the surface functionalisation on the NP dispersion Coating is often used by suppliers to improve NP dispersion, but is rarely specified. stabilisation bio ‐ electrostatic or sterric repulsions favour dispersion available ionic strength pH aggregation not bio ‐ no surface charge available favours aggregation
C ‐ Aggregation kinetic vs adsorption onto biological surface: CeO2 + salt + cells stable NPs In water : Initial conditions: only adsorption 3 mg/l NPs 10 8 cells/ml unstable NPs = In medium : adsorption + aggregation t ~ 1s Zeyons et al, ES and T 2009
Adsorption of CeO2 onto biological membrane and floculation Synechocystis PCC 6803 E. coli Zeyon, Thill et al
Forte affinité vis à vis du vivant Ex E Coli or Synechocystis cells mais pas de toxicité si absence de contact direct Zeyon, Thill et a ES and T 2008 et Langmuir 2009
D ‐ Biodisponibility: Strong affinity for Eucaryotes cells and endocytosis: ex γ Fe 2 O 3 or CeO 2 M.Auffan et al, ES and T 2006; M Auffan et al, Nanotoxicology 2009
Toxicité: mécanismes Adapted from A Nel UCLA 2009
Environmental behavior and (eco)toxicity • Trophic transfer via A terrestrial A marine food chain food chain food webs Quaternary consumers Hawk Killer whale Tertiary consumers Snake Cod Secondary consumers Mouse Herring Transformation? Primary consumers Grasshoper Zooplancton Producers Majorité des travaux Flowers Phytoplancton bacterias.. http://www.pearsonsuccessnet.com/iText/products/0 ‐ 13 ‐ 115075 ‐ 8/text/chapter36/concept36.1.html
Toxicité vis à vis des micro ‐ organismes bactériens Toxicité vis à vis des micro ‐ organismes bactériens Dissolution/aggregation NP Reactivity Membrane Integrity ROS production test Rouge neutre O 2 ‐ , O 2 • ‐ , OH • Cristalline Defects mitochondrial ROS detection activity TEM, Diffraction WST1 test Surface Spéciation ROS Internalisation and reactivity oxydant stress TEM; Micro ‐ fluorescence.. EXAFS, XANES, RMN, FTIR Anti ‐ oxydants, mutant strains Cytotoxicity ADN comets tests synchrotron Génotoxicity Chromosomes Micronuclei tests
Réglons la question: Est ce que l'agrégation contrôle la toxicité ? Nano ‐ γ Fe 2 O 3 Nano ‐ CeO 2 enrobées 2.5 ‐ 3 μ m Toxique Non toxique 50 ‐ 100 nm Cellules Cellules Eucaryotes Eucaryotes
Two examples CeO 2 = Slow Chemical solubility Fe° = Very weak stability
Interactions NP / procaryote cells on mutant and wild strains Interactions NP / procaryote cells on mutant and wild strains CeO 2 Fe 0 γ Fe 2 O 3 E.coli 7nm < 20nm 6nm E.coli E.coli No cytotoxicity Cytotoxicity ≤ 10 mg/L Cytotoxic > 70 mg/L No cytotoxic No structiural 30% of Ce(IV) ‐ > Ce(III) on Oxydation of Fe° the surface of Cerine Dissolution / precipitation modification Ce 4+ Fe 0 γ FeOOH e ‐ , ROS production γ Fe 2 3+ O 3 Ce 3+ Fe 3 O 4 Fe 2+ , ROS Toxicity is associated to the chemical instability of NP Damage membrane stable Redox cycle (Ce 3+ /Ce 4+ ) Fenton Reaction (Fe 2+ ) Zeyons et al, ES and T 2008; Stress oxydatif through ROS production M Auffan et al, Nanotoxicology 2009
Interactions NP with eucaryote cells Interactions NP with eucaryote cells CeO 2 7nm Ce 4+ e ‐ , ROS Xanes at L3 edge of Ce = Reduction of Ce(IV) in 30% of reduced surface atoms Ce(III) Ce 3+ Stress oxydatif No cytotoxic effects but … génotoxicity at very low … concentrations > 0,06 mg/L ADN and chromosomic 0,06 mg/L Damages micronoyaux 60 mg/L control M.Auffan et al, ES and T 2006; M Auffan et al, Nanotoxicology 2009
Environmental behavior and (eco)toxicity • Trophic transfer via A terrestrial A marine food chain food chain food webs Quaternary consumers Hawk Killer whale Tertiary consumers Snake Cod Secondary consumers Mouse Herring Travaux qui se développent: Primary consumers Grasshoper Zooplancton cf I ‐ CEINT = mésocosmes Producers Flowers Phytoplancton bacterias.. http://www.pearsonsuccessnet.com/iText/products/0 ‐ 13 ‐ 115075 ‐ 8/text/chapter36/concept36.1.html
Physical-chemical characterization and ecotoxicity of residues from alteration of engineered nanomaterials Ex: Ag°, Solar creams with TiO2
Toxicity of coated ‐ silver nanoparticles : C.elegans PVP coated Nano ‐ Ag 0 21 ± 17 nm Ag 0 Caenorhabditis Caenorhabditis elegans elegans Wild and transgenic strains Mtl2: deficient in protein involved in metal regulation and detoxification M Auffan In collaboration with J. Meyer (DUKE university, USA)
Toxicity of coated ‐ silver nanoparticles : C.elegans Dissolved Ag effect 24h 24h Mtl2 strain more sensitive than the wild 48h 48h 72h 72h Wild Mtl2 PVP ‐ nanoAg In collaboration with J. Meyer (DUKE university, USA)
Toxicity across a salinity gradient : Fundulus heteroclitus Simulated silver speciation Fundulus heteroclitus Assessing toxicity across a salinity gradient Sea Water Tolerate Tolerate Tolerate Tolerate Low Salt PVP coated nanoAg 0 Gum Arabic coated nanoAg 0 21 ± 17 nm 7 ± 3 nm In collaboration with C. Matson, R. Digiulio (DUKE university, USA)
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