Parallel session 2

1. Study on the penetration of TiO2 nanoparticles
through protective clothing and gloves
in conditions simulating occupational use
Ludwig Vinches, Mehdi Ben Salah, Nicolas Testori,
Gérald Perron, Patricia Dolez*, Kevin J. Wilkinson**, Stéphane Hallé
École de technologie supérieure
*Groupe CTT, Saint-Hyacinthe
**Université de Montréal

2. Context
• Increasing number of people (6 millions in 2020) exposed to nanoparticles (NPs)
Scientists in laboratories
Workers in companies
• Increasing evidence that skin is not an impervious membrane for NPs
Penetration of NPs when skin is injured by abrasion
after repeated flexions
or even intact
Need for dermal protection
Precautionary principle : use of protective clothing and gloves
against chemicals
At the best of our knowledge, no study about the penetration of NPs
through protective clothing and gloves in working conditions
Ludwig Vinches et al. – Ne3LS 2012 2

3. Materials Protective clothing and gloves / nanoparticles
 Nitrile rubber (NBR) (t = 100 µm) nTiO2 - 15 nm, 99.7% pure anatase powder
Pores
Anatase TEM
SEM x300
Rutile
 Butyl rubber (IIR) (t = 700 µm)
3-6%
Platelets 50 nm
Statistical study on 174 particles
Aggregates ≈ 80 to 100 nm
Agglomerates: up to 1 µm
SEM x300
 Nonwoven coverall material (NWC) in polyolefin Commercial nTiO2 solutions
 15 nm, anatase, 20 wt% in 1,2-propanediol (PG)
Pores
 15 nm, anatase, 15 wt% in water
Mass fractions and sizes of nanoparticles
similar to manufacturer data (TGA & FCS)
SEM x300
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4. Setup
Cylinders
Deformation
probe
Exposure
chamber
In a glove box
Sample
Sampling
chamber
Deformation probes
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5. Results on NP penetration Sampling protocole
Sampling protocole
using sampling solutions
Sampling solution = UHP H2O
Exposure Centrifugation on mica substrates
chamber nTiO2 powder or for Atomic Force Microscopy (AFM)
colloidal solution
Sampling solution = UHP H2O + 1% HNO3
Sample
Sampling Inductively Coupled Plasma – Mass
chamber Sampling solution Spectroscopy (ICP-MS)
Atomic Absorption Spectroscopy
(AAS)
• No contact with the sample during the test
• Used to rinse the chamber walls after the
test
Ludwig Vinches et al. – Ne3LS 2012 5

6. Results on NP penetration through gloves ICP-MS analysis – nTiO2 in water
25
20 NBR (without nTiO2 in water)
Exposure nTiO2 solution NBR (with nTiO2 in water)
Ti4+ Concentration (µg/L)
chamber in water IIR (without nTiO2 in water)
15 IIR (with nTiO2 in water)
Sample
Sampling 10
chamber Sampling
solution 5
50% - Biaxial
0
deformation 0 1 2 3 4 5 6 7 8
Experiment duration (h)
5 min
Penetration of nTiO2 in water
through nitrile rubber after deformations
Strain
No penetration of nTiO2 in water
through butyl rubber
Time
Ludwig Vinches et al. – Ne3LS 2012 6

7. Elastomer behaviour Effect of nTiO2 liquid carriers and deformations on the sample surface
Surface feature identification : SEM – 5 kV
Surface feature quantification : image processing
80
Exposure Unexposed
chamber Solvent Exposed to PG (7h)
70 Dynamic biaxial deformation (7h)
Dynamic biaxial deformation + PG (7h)
Surface feature quantification (%)
60
Outer surface
50
Sample
Sampling
chamber 40
30
50 % - Biaxial 20
deformation
10
0
5 min
Nitrile rubber Butyl rubber
Strain
Solvent or deformation : Surface damage
Solvent + deformation : Lubrication effect
Time
Ludwig Vinches et al. – Ne3LS 2012 7

8. Gravimetric measurements Effect of nTiO2 solutions
40
nTiO2 in water Nitrile rubber
nTiO2 in PG
30
Short immersion time
Mass gain (%)
20 Mass gain after 8h-immersion (%)
nTiO2 in water nTiO2 in PG
10
35 15
0 Due to the difference in viscosity and polarity
0 100 200 300 400 500
Immersion time (min) between the two solvents families
80 Long immersion time
70
A plateau in the swelling curves is observed
60 after 40 h of immersion
Nitrile rubber (nitrile rubber)
Mass gain (%)
50
Butyl rubber
40
No significant mass gain is recorded
30
for butyl rubber
20
nTiO2 in water Mass gain after 40h-immersion (%) in nTiO2 in water
10
Nitrile rubber Butyl rubber
0
0 10 20 30 40 50 60 70 80
Immersion time (h)
73 0
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9. Results on NP penetration through gloves ICP-MS analysis – nTiO2 in powder
25
NBR (without nTiO2 powder)
NBR (with nTiO2 powder)
IIR (without nTiO2 powder)
Exposure 20
IIR (with nTiO2 powder)
chamber nTiO2
Ti4+ concentration (µg/L)
powder
15
Sampling Sample
10
chamber Sampling
solution
5
50% - biaxial
0
deformation 0 1 2 3 4 5 6 7 8
Experiment duration (h)
5 min
Penetration of nTiO2 in powder
through nitrile rubber after deformations
Strain
No penetration of nTiO2 in powder
through butyl rubber
Time
Ludwig Vinches et al. – Ne3LS 2012 9

10. Results on NP penetration through gloves AFM analysis – nTiO2 in powder
Mica substrate
Exposure nTiO2 before centrifugation
chamber powder
Sample
Sampling
chamber Sampling
solution
50% – biaxial
deformation – Mica substrate
7h after centrifugation of a
sampling solution
5 min
(Nitrile rubber – 7h)
Penetration of nTiO2 powder
Strain
through nitrile rubber after deformations
Confirmation of ICP-MS analysis
Time No information on chemical composition of the NPs
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11. Results on NP penetration through gloves
nTiO2 in powder nTiO2 in solution
80
Unexposed
40
Exposed to PG (7h) nTiO2 in water
70 Dynamic biaxial deformation (7h)
nTiO2 in PG
Dynamic biaxial deformation + PG (7h)
Surface feature quantification (%)
60
30
50
Mass gain (%)
40
20
30
20 10
10
0 0
Nitrile rubber Butyl rubber 0 100 200 300 400 500
Immersion time (min)
25 25
NBR (without nTiO2 powder)
NBR (with nTiO2 powder)
20 IIR (without nTiO2 powder)
20 NBR (without nTiO2 in water)
IIR (with nTiO2 powder)
NBR (with nTiO2 in water)
Ti4+ concentration (µg/L)
Ti4+ Concentration (µg/L)
IIR (without nTiO2 in water)
15 15 IIR (with nTiO2 in water)
10 10
5 5
0 0
0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8
Experiment duration (h) Experiment duration (h)
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12. Results on NP penetration through NWC AAS analysis – nTiO2 in PG
8000
7000
Exposure nTiO2 solution
chamber 6000
Ti4+ Concentration (mg/L)
in PG
5000
4000
Sample
Sampling
3000
chamber Sampling
solution 2000
1000
10% - Biaxial 0
deformation 0 1 2 3 4 5 6 7 8
Experiment duration (h)
5 min
Penetration of nTiO2 in PG
Strain
through nonwoven coverall
after deformations
Time
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13. Fabrics behaviour Effect of deformations on the water vapor permeability
140000
Unexposed
Dynamic biaxial deformations (5h)
130000
1,2-propanediol + deformations (5h)
120000
Outer surface
Permeation (g.m/m²/day)
Solvent
110000
Exposure (PG)
chamber 100000
90000
Sample
Sampling 80000
chamber 70000
60000
10 % - Biaxial 50000
deformation 0 50 100 150 200 250 300 350
Time (min)
5 min
Deformation :
• A significant decrease in water vapor permeability
• Reduction of the pores size
Strain
Deformation + solvent :
• Lubrication effect
Time
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14. Results on NP penetration through NWC AAS analysis – nTiO2 powder
2500
With nTiO2 powder
Without nTiO2 powder
Exposure 2000
chamber nTiO2
Ti4+ Concentration (µg/L)
powder
1500
Sampling Sample
1000
chamber Sampling
solution
500
10% - biaxial 0
deformation 0 1 2 3 4 5 6 7 8
Experiment duration (h)
5 min
Penetration of nTiO2 in powder
Strain
through nonwoven coverall
after deformations
Time
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15. Conclusions
 Development of a test method for protective clothing and gloves against NPs in
conditions simulating occupational use
• Experimental setup + NP detection techniques
• NPs: powder and in colloidal solutions
• Mechanical deformations / glove microclimate
 Glove material behaviour after mechanical deformations
• Surface damage / Lubrication effect
• Swelling effect
 Nonwoven coverall material behaviour after mechanical deformations
• Water vapor permeability decrease
• Lubrication effect
Penetration of TiO2 nanoparticles
(in powder and solutions)
through nitrile rubber protective gloves and nonwoven coverall
after deformations
Need for further investigations
Ludwig Vinches et al. – Ne3LS 2012 15

16. With the collaboration of :
Swann Mahé, Alice Jambou, Félicien Deltombe,
Pierre-Emmanuel Daure-Cagnol, Maud Leblanc (ÉTS)
Yves Cloutier, Chantal Dion, Ginette Truchon (IRSST)
Gilles l’Espérance, Philippe Plamondon (École Polytechnique de Montréal)
And the support of the :
Research chair in protective materials and equipment for occupational safety and
health , ÉTS
Ludwig Vinches et al. – Ne3LS 2012 16

17. Thank you
for your attention
Ludwig Vinches et al. – Ne3LS 2012