toxicologie de nanoparticules métalliques à de faibles concentrations, pertinentes du point de vue...
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Toxicologie de nanoparticules métalliques à de faibles concentrations, pertinentes du point de vue environnemental
CNRS, UMR EPOC 5805Université de Bordeaux
Station marine d’Arcachon
par Jean-Paul Bourdineaudprofesseur, Université de Bordeaux
1er CONGRÈS SANTÉ-ENVIRONNEMENTOrganisé par l’URPS-Médecins libéraux de PACA
6 & 7 Décembre 2013Marseille - Palais du Pharo
Comment des nanoparticules peuvent-elles être introduites dans un système écologique ?
Quelle peut être l’ampleur de la pollution ?
Kaegi et al., Environmental Pollution, 156 (2008) 233-239
Fresh facade painting
Older facade painting
Collected particles from runoff events Concentration of micro and nanoparticles in rain runoffs
Les nanoparticules peuvent-elles être distribuées dans les différents compartiments d’un système écologique ?
Et si oui, quel est le niveau de transfert vers les différentes composantes biologiques ?
(Ferry et al.)
A single dose, 7.1 x 1011 of gold nanorods/L (65 x 15 nm), making 157 g Au NPs/L.
Genotoxic impact of metal nanoparticles on the zebrafish Danio rerio
Gold nanoparticles are used in pregnancy tests, toothpaste, energizing creams and beverages, detection and treatment of cancer tumours.Cadmium sulfide nanoparticles are used in electronic devices.
MesoGold, 20 ppm colloidal gold, 250 mL, by Purest ColloidsPrice: $29.97Fulfilled by Amazon (Gift-wrap).Supports mental focus & concentration, and improved hand/eye coordination.Promotes improved memory & a general feeling of well being.
Impact of cadmium sulfide and gold nanoparticles on the zebrafish
Controls
CdS (10 nm) CdS (50 nm) Au (12 nm) Au (50 nm)
Contamination through diet (5 µg nanoparticles/g food)giving 40 ng nanoparticles/fish/day
Exposure length: 60 days
100 nm 100 nm
Nanoparticles embedded in the food
12 nm NPs 50 nm NPs
Metal quantification (cadmium and gold) in zebrafish
tissues after 60 days of exposure.
Gold could not be quantified in tissues and even in whole fish.Detection limits by atomic absorption spectrometry :Cadmium : 0,1 µg/L Gold : 1 µg/L
Diet Liver Brain Muscles Whole fish
Control food 8 ± 8 9 ± 0,9 0,6 ± 0,1 32 ± 8
CdS (10 nm) 348 ± 30 19 ± 3 1,8 ± 1 170 ± 10
CdS (50 nm) 364 ± 30 10 ± 3 3,1± 1 50 ± 5
Liver is the organ accumulating the most cadmiumThe little nanoparticles are more accumulated than the bigger in the brain and at the scale of the whole fish.
Total Cd in ng/g
Differential gene expression after 60 days of exposure
sod1 sod2 mt 2 rad 51 c-jun p53 bax pyc cox1
Liver
Au (12 nm) 1/18 1/381 1/71 1/10 1/27 1/45 1/20 1/9 1/12
Au (50 nm) / 1/28 / / 1/7 1/16 1/4 / /
CdS (10 nm) / 1/7 123 3 1/6 / 1/2 / 1/4
CdS (50 nm) 1/3 1/23 1/23 / 1/6 / 1/5 1/5 /
Brain
Au (12 nm) 2 3 3 2 38 20 8 26 1/9
Au (50 nm) / 5 / / 5 6 / 4 1/38
CdS (10 nm) / 2 25 / / 2 / 1/5 /
CdS (50 nm) 3 3 3 / 10 / 2 7 /
Muscle
Au (12 nm) / / / / 1/2 / / 9 /
Au (50 nm) / / / 1/3 3 / 1/3 1/6 1/16
CdS (10 nm) 5 10 20 32 6 12 4 / /
CdS (50 nm) / 0,4 / 2 / / / / 1/15
Oxidative stress Detoxication
DNA repair
General stress
Mitochondrial
metabolism
1/ CdS and gold nanoparticles trigger a different gene expression pattern.2/ Size does matter !
Control DNA Contaminated DNA
Pollutant
Probe OPB
OPBOPB
OPB
OPB
Loss of hybridization site
Principle of RAPD (Random amplified polymorphic DNA)
OPB
OPBOPB
OPB
Principle of RAPD (Random amplified polymorphic DNA)
OPB
OPBOPB
Control DNA
Creation of hybridization site
Contaminated DNA
Quantification of genotoxic damages by RAPD-PCR methodology
RAPD probe Témoins CdS (10 nm) CdS (50 nm) Au (12 nm) Au (50 nm)
OPB70,6 ± 0,1 0,7 ± 0,1 * 6,5 ± 0,9 * 8,5 ± 0,9 * 1,9 ± 0,2
OPB11 (2,1 ± 0,7).10-5 * (31 ± 14).10-5 * (4300 ± 1800).10-5 * (5600 ± 1800).10-5 * (280 ± 70).10-5
1/ The numbers of hybridization sites for RAPD probes was modified by nanoparticles. 2/ The two metals presented different effects.3/ Size still matters !
Genomic DNAs were extracted from whole zebrafish individuals
Number of hybridization sites per genome of the RAPD probe
RAPD probes’ sequences:
OPB7 : 5’-GGTGACGCAG-3’OPB11 : 5’-GTAGACCCGT-3’
n = 10, mean ± SEM
Les nanoparticules piégées dans les sédiments aquatiques peuvent-elles être libérées dans la colonne d’eau et représenter un risque pour la santé des animaux ?
Impact of gold nanoparticles (14 nm) on zebrafish exposed to a spiked sediment
Brain AChE activity(nmol/mg/min)
Brain ache gene expression(relative to bactin gene)
440 ± 17 546 ± 8 551 ± 22
0.08 ± 0.01 0.10 ± 0.01 0.33 ± 0.05
Controls
Au (16 mg/kg)
Au (55 mg/kg)
Exposition : 20 days
0.25 g/L 0.8 g/L
Les nanoparticules incluses dans les sols peuvent-elles représenter un risque pour la santé des animaux ?
Metal nanoparticles trigger an oxidative stress in the earthworm Eisenia fetida
Silver nanoparticles are used as antibacterial and antifungal agents in textiles, water treatments, and medical devices.
Impact of gold and silver nanoparticles on the red earthworm
Contamination through the soilExposure length: 10 days
Controls
Gold NPs
Ionic gold
Silver NPs
Ionic silver
2, 10, and 50 mg/kg
2, 10, and 50 mg/kg
Lipid peroxidation and protein oxidation in earthworms exposed for 10 days to ionic and nanoparticular god and silver
Lipid peroxidation Protein carbonylation
MDA : malondialdehyde
CH2 CC
HH
OO
Counter-adaptive levels of catalase in earthworms exposed for 10 days to ionic and nanoparticular gold and silver
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0 mg/kg 2 mg/kg 10 mg/kg 50 mg/kg
CA
T (
mo
l min
-1 m
g-1
pro
tein
)
Au-NP Ag-NP Au Ag
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*
*
*
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