Supplemental Data
Aquatic Toxicity of Nano-Silver Colloids to Different Trophic Organisms: Contributions
of Particles and Free Silver Ion
Zhuang Wang†‡§, Jingwen Chen*†, Xuehua Li†, Jianping Shao†, and Willie J.G.M.
Peijnenburg*‡§
†
Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of
Environmental Science and Technology, Dalian University of Technology, Dalian, China
‡
Laboratory for Ecological Risk Assessment, National Institute of Public Health and the
Environment (RIVM), Bilthoven, The Netherlands
§
Institute of Environmental Sciences (CML), Faculty of Science, Leiden University, Leiden,
The Netherlands
 Corresponding authors:
Jingwen Chen: jwchen@dlut.edu.cn, W. Peijnenburg: Willie.Peijnenburg@rivm.nl
8 Pages
5 Figures
4 Tables
S1
Table S1. Information of the commercial nano-silver (nAg)
Material
Primary particle size
Bare-nAg
35 nm
Purity
Details
99.5% (metal
Powder; SSA: 30-50 m2/g; particle
basis)
morphology: spherical
Aqueous dispersion; dispersant: 4% each of
15 nm (90% < 20
polyoxyethylene glycerol trioleate and
DIS-nAg
10.16% w/w
nm)
polyoxyethylene (20) sorbitan mono-laurat
(Tween 20); particle morphology: spherical
Powder; w/~0.3% PVP
99.9% (metal
80 nm
(polyvinylpyrrolidone); particle
basis)
morphology: spherical
400
Measured potential (mV)
PVP-nAg
300
200
y = 51x + 514
r2 = 0.99
100
-8
-6
-4
-2
+
log [Ag ] (M)
Fig. S1. Linear calibration for free ionic silver (Ag+)
S2
Table S2. Developmental morphology and teratogenicity endpoints in the
zebrafish (Danio rerio) test
Toxicological endpointsa
Exposure time
24 hrs
48 hrs
72 hrs
96 hrs
tail detachment
*
*
*
*
formation of somites
*
*
*
*
Eyes
*
*
*
*
Movement
*
*
*
*
Heartbeat
*
*
*
*
blood circulation
*
*
*
Pigmentation
*
*
*
pectoral fin
*
*
protruding mouth
*
*
Morphology
Teratogenicity
pericardial oedema
*
*
*
*
yolk sac oedema
*
*
*
*
eye oedema
*
*
*
*
head malformation
*
*
*
*
absence/malformation of sacculi/otoliths
*
*
*
*
malformation of tail
*
*
*
*
malformation of heart
*
*
*
*
modified chorda structure
*
*
*
*
scoliosis
*
*
*
*
rachischisis
*
*
*
*
yolk deformation
*
*
*
*
a
 represents the observed toxicity endpoints.
S3
Table S3. Size and charge characterization data for the nano-silver (nAg) with different initial particle
concentrations of suspension in the test medium a
1000 µM
10 µM
ζ-potential
(mV)
MED
(nm)
MOD
(nm)
ζ-potential
(mV)
MED
(nm)
MOD
(nm)
Bare-nAg
-23.2 ± 0.6
189
145
-21.3 ± 0.3
225
210
DIS-nAg
-10.3 ± 1.0
115
95
-13.9 ± 3.0
200
210
PVP-nAg
-24.1 ± 1.2
196
113
-20.6 ± 1.5
310
270
a MED
= Mean particle diameter (particle concentration distribution), measured at pH 7.0; MOD = Mode
diameter (particle concentration distribution), measured at pH 7.0; ζ-potential = zeta potential, measured at
pH 7.0.
S4
20
Particle fraction (%)
Particle fraction (%)
25
1000 µM
Bare-nAg
16
12
8
4
0
20
15
10
5
0
0
100
200
300
400
500
0
100
Diameter (nm)
300
400
500
24
1000 µM
DIS-nAg
200
Diameter (nm)
4.5
3.0
1.5
10 µM
DIS-nAg
Particle fraction (%)
Particle fraction (%)
6.0
0.0
18
12
6
0
0
100
200
300
400
500
0
100
Diameter (nm)
20
300
25
1000 µM
PVP-nAg
200
400
500
Diameter (nm)
16
12
8
4
0
10 µM
PVP-nAg
Particle fraction (%)
Particle fraction (%)
10 µM
Bare-nAg
20
15
10
5
0
0
100
200
300
400
Diameter (nm)
500
600
0
100
200
300
400
500
600
Diameter (nm)
Fig. S2. Particle size distribution of the nano-silver (nAg) with different initial particle
concentrations of suspension in the test medium
S5
1000 µM
10 µM
90
24 h
48 h
96 h
80
20
Ba
Ba
0
re
-n
Ag
D
IS
-n
PV Ag
PnA
g
10
re
-n
Ag
D
IS
-n
PV Ag
PnA
g
Ctotal Ag/ Cinitial nAg(%)
100
Fig. S3. Ratios of total silver concentration (Ctotal Ag) in the colloids to different initial
nano-silver (nAg) concentrations (Cinitial nAg)
CAg+/ Ctotal nAg(%)
25 1000 µM
20
0 h 10 µM
24 h
48 h
96 h
15
10
5
Ba
re
-n
Ag
D
IS
-n
Ag
PV
PnA
g
Ba
re
-n
Ag
D
IS
-n
A
PV g
PnA
g
0
Fig. S4. Ratios of free ionic silver (Ag+) concentration (CAg+) to total silver concentration
(Ctotal Ag) in the colloids with different initial nano-silver (nAg) concentrations
S6
Table S4. Estimated median effect concentrations (EC50) of the nano-silver (nAg) agglomerated particles
to aquatic organisms of different trophic levels
EC50 (µM) a
Model\b
ρ
R. subcapitata
Bare-nAg
1112.63
Sigmoidal Sigmoid
256.27
DIS-nAg
8.61 [7.98-8.98]
Sigmoidal Sigmoid
0.19
PVP-nAg
40.2 [35.25-43.77]
Sigmoidal Sigmoid
12.66
C. sphaericus
Bare-nAg
1.19 [1.03-1.25]
Sigmoidal Sigmoid
0.13
DIS-nAg
0.45 [0.16-0.73]
Sigmoidal Sigmoid
0.39
PVP-nAg
0.34 [0.30-0.37]
Sigmoidal Sigmoid
0.19
D. rerio
a
Bare-nAg
1.95 [1.83-2.07]
Sigmoidal Sigmoid
0.91
DIS-nAg
0.82 [0.76-0.86]
Sigmoidal Sigmoid
0.23
PVP-nAg
1.50 [1.45-1.55]
Sigmoidal Sigmoid
0.74
The median effect concentration (EC50) values are given with 95% confidence intervals listed in the
brackets.
b
Function and corresponding model. Sigmoidal Sigmoid: E=1/(1+exp(-(c- EC50)/ρ)), where ρ = slope.
S7
1000
R. subcapitata
EC50 ( µM)
100
10
C. sphaericus
1
D. rerio
0.1
0.01
0.1
1
10
100
+
Free Ag concentration ( µM)
Bare-nAg (1000 µM)
DIS-nAg (1000 µM)
PVP-nAg (1000 µM)
Bare-nAg (10 µM)
DIS-nAg (10 µM)
PVP-nAg (10 µM)
Fig. S5. Median effect concentration (EC50) of the nano-silver (nAg) colloids expressed as a
function of the free ionic silver concentration in the colloids with different initial nAg particle
concentrations
S8