Dynamics of dissolved (< 0.45 µm) trace elements and organic matter in tributary mixing zones of the lower Athabasca River, Alberta Chad W. Cuss, Mark W. Donner, Marjan Ghotbizadeh, Tommy Noernberg, and William Shotyk SWAMP lab facility Department of Renewable Resources University of Alberta
[email protected]
Natural vs industrial sources of trace elements in the Lower Athabasca River (LAR)
Image courtesy Jon Fennell
2
Natural vs industrial sources of trace elements in the Lower Athabasca River (LAR) Emissions from city
Organic matter and trace elements from tributaries
Fugitive dust emissions
Petroleum coke
Other industry Natural bitumen outcrops Stack emissions, tailings ponds
Natural bitumen/bank dust
3 3
Industrial Tributariesactivity governincreases trace element trace element concentrations? concentrations? Muskeg R.
10.000
Upstream
Midstream
Downstream
Dissolved conc. (log µg L-1)
Midstream 1.000
Downstream
0.100
Upstream Midstream 0.010 Clearwater R.
Li
V
Mn
Fe
Co
Y
Pb
Horse R.
4
Tributaries govern trace element concentrations? Muskeg R.
10.000
Upstream
Upstream Midstream Downstream Midstreamtribs Midstream
100.000
Downstream
µgLL-1-1) ) (logµg conc.(log Dissolved Dissolvedconc.
Midstream 1.000 10.000
Downstream
1.000 0.100 0.100
Upstream Midstream
0.010 0.010 Clearwater R.
Li Li
V V
Mn Mn
Fe Fe
Co Co
YY
Pb Pb
Horse R.
5
Size distribution of colloidal carriers in the dissolved phase (< 0.45 µm)
Dissolved organic matter • Exudates and metabolites • Degradation products • Humic and fulvic acids • Polydisperse, polyfunctional, polyelectrolyte M+ M+
M+
M+
M+ M+
M+
Mainly ionic species • Hydrated ions • Small inorganic complexes (e.g. carbonates) + M-CO3
M
Mainly inorganic • Free/hydrated metal ions • Amorphous oxyhydroxides, clays, other minerals • Trapped and adsorbed trace elements • DOM adsorbed to surfaces M+
M+
M+
M+ M+
M+
M+
M+
M+ M+ Modified from Lead JR, Wilkinson KJ (2006) Aquatic colloids and nanoparticles: current knowledge and future trends. Environ. Chem. 3:159–171.
• Distribution of TE sensitive to temperature, shear, pH and ionic strength
6
Challenge: natural [trace elements] can be ultra-trace Total [Pb] in river: 221 ng L-1 Particles (> 0.45 µm) 210 ng L-1, 95%
Bound to Organic matter ? Bound to Fe/Mn/Al ?
Dissolved (< 0.45 µm) 11 ng L-1, 5%
221 ng L-1 ≈ 0.0000002 g in 1 L
≈
‘Truly dissolved’ & mainly ionic species
in: ≈ 0.5 g ≈ 2,500,000 L 7
ICAP Qc ICP-QMS
Element XR ICP-SFMS
Metal-free, ultraclean research facility
Sub-boiling distillation of HNO3 in high purity quartz
Autosampler within Class 100 clean air cabinet
High pressure microwave acid digestion system
Flow-field flow-fractionation (with 3 detectors) coupled to ICP-MS for size-resolved trace metal analysis of waters
Water dispenser within 8 Class 100 clean air cabinet
AF4-ICPMS flow program, LODs, and precision Element LOD (ng L-1) 7Li 37.2 24Mg 390.8 27Al 188.1 51V 10.2 55Mn 64.3 56Fe 599.0 57Fe 623.9 59Co 8.7 60Ni 323.4 63Cu 213.5 66Zn 657.5 75As 5.3 88Sr 105.4 89Y 7.5 95Mo 31.9 137Ba 107.5 208Pb 2.7 232Th 4.0 238U 0.9 SRNOM standard: MP ± 95% CI = 986 ± 6 Da (n = 5)
Eluent: Buffer from 99.999% trace metal free (NH4)2CO3 (pH ranges ~5.5–7, 8–10) Crossflow: 2.1 mL min-1 for 29 min. + 1 min. linear decrease to zero + 0 mL min-1 for 20 min. Channel/detector flow: 0.7 mL min-1 Inlet flow: 0.2 mL min-1 Focus time: 6 min. Elution time: 44 min. Cleaning cycle: 5 min. at 4 mL min-1 9 Total run time: 55.2 min./sample
AF4-UV-ICPMS UV-Visible absorbance Flow
Absorbance (254 nm)
AF4
ICP-MS (quadrupole)
80
Organic matter
60
40
Flow
20
0 400
500
600
700
800
900
5
40 30
Muskeg Atha. R.
20 10
4
Percentage of retained Fe
3 2
0%
20%
40%
60%
80%
1
100%
0
0 500
600
Void peak + mainly ionic
1000
1500
2000
Retention time (s)
3000
Large mainly inorganic/Fe-associated
DOM-bound
56
500
Muskeg R.
2500
Fe (ng L-1)
14 12 10
400 300
Small mainly inorganic/Fe-associated
200
8
Crossflow turned off
6 4
100
2 0
0 500
1000
1500
Retention time (s)
2000
2500
Athabasca R. (site WWTP)
Muskeg MuskegR.R.
6
DOM (A254, mAU)
50
Athabasca R. (site WWTP)
Time (seconds)
3000
10
Muskeg R.
500
0% DOM-bound
50%
Large mainly inorganic/Fe-associated
100%
56
Fe (ng L-1)
14 12 10
400
8
300
Small mainly inorganic/Fe-associated
200
6 4
100
2
0
0 500
1000
1500
2000
2500
Athabasca R. (site WWTP)
600
Void peak + mainly ionic
Percentage of retained Fe
Muskeg Atha. R.
3000
Retention time (s)
Site WWTP (upstream) 100%
Large inorganic
80%
Small inorganic
60%
40%
DOM-bound
20%
Mainly ionic
0%
Midstream tributary (Steepbank R.) 100% 80% 60% 40% 20% 0%
11
Tributary inputs govern dissolved concentration and speciation Upstream
Dissolved concentration (log µg L-1)
100.00
Midstream Downstream
10.00
Midstream tribs
1.00 0.10
Bound conc. (log µg L-1)
0.01 Li
V
Mn
Mn
Fe
Co
Fe
Co
Y
Pb
10.00 1.00 0.10 0.01 0.00
Zn
As
Pb
U 12
How well do the tributary inputs mix with the mainstem, and how representative are these single samples?
13
Metal-free depth sampling with ‘the fish’ and ‘portable clean room’ Tommy Noernberg Mechanical Engineering Technologist
14
Mixing transect: Horse River and AR 600 500 400 300 200 100 0
Pb, 15 ppb
300
800
1300
1800
2300
600 500 400 300 200 100 0
Pb, 26 ppb
300
2800
250000
Fe, 77 ppb
80000
150000
40000
100000
20000
50000
0
0 300
500
1300
300
2300
Pb, 21 ppb
400
1300
1800
2300
2800
Fe, 256 ppb
200000
60000
800
1500
1300
2300
Pb, 52 ppb
1000
300 200
500
100 0
0
300
800
1300
1800
2300
300 600000
Fe, 79 ppb
80000
2800
400000
40000
300000
1300
1800
2300
Fe, 719 ppb
500000
60000
800
200000
20000
100000
0
0 300
1300
2300
300
1300
2300
2800
Upstream
Upstream transects
Clearwater R. 16
Horse R.
Upstream of WWTP
17
Velocities for upstream of WWTP Distance from west shore (m) 0
50
100
150
200
250
300
0.0
1.55 m s-1
1.22 m s-1
1.04 m s-1
1.14 m s-1
0.88 m s-1
Depth (m)
-0.5
-1.0
1.46 m s-1
-1.5
-2.0
0.61 m s-1 0.61 m s-1
0.81 m s-1
-2.5
-3.0 18
Iron (Upstream WWTP) 100000
100000
80000
80000
80000
60000
60000
60000
40000
40000
40000
20000
20000
20000
0
0
0
100000
300
800
1300
1800
2300
2800
300
800
1300
1800
2300
2800 300 100000 80000 60000 40000 20000 0
800
1300
1800
2300
280
300
800
1300
1800
2300
2800
800
1300
1800
2300
280
1300
1800
100000 80000 60000 40000 20000 0
100000 80000 60000 40000
300
20000
100000
0 300
800
1300
1800
2300
2800
100000
80000
80000
60000
60000
40000
40000
20000
100000
20000
0
80000
0 300
800
1300
1800
2300
2800
300
800
2300
2800
60000 40000 20000 0 300
800
1300
1800
2300
2800
19
600000
Fe, Horse River 500000
Large Fe-associated Void peak
400000 CPS
DOM-associated 300000
Small Fe-associated
200000
100000
0 300
400000
800
1300
1800
350000
Fe, Clearwater River (0.3 m depth)
350000
300000
300000
250000
250000
200000
200000
150000
150000
2300
2800
Fe, Clearwater River (1.5 m depth)
100000
100000
50000
50000 0 300
0 300
800
1300
1800
2300
2800
800
1300 1800 Retention time (s)
2300
2800
Upstream of McLean Ck/A19
21
Velocities for upstream from McLean Ck. Distance from west shore (m) 0
50
100
150
200
250
300
350
400
450
0.0
0.46 m s-1
0.91 m s-1
0.88 m s-1
-0.5
Depth (m)
0.40 m s-1
-1.0
0.76 m s-1 -1.5
0.79 m s-1
0.67 m s-1
-2.0
-2.5
0.55 m s-1
-3.0
22
Iron (Upstream McLean Ck.)
80000
80000
60000
180000 150000
60000
120000
40000
40000
20000
90000 60000
20000
30000
0 300
800
1300
1800
2300
2800 0
0 300
80000
80000
60000
60000
40000
40000
20000
20000
800
1300
1800
2300
2800
300
800
1300
1800
2300
2800
300
800
1300
1800
2300
2800
300
800
1300
1800
2300
180000 150000 120000 90000 60000 30000
0
0 300
800
1300
1800
2300
2800
0 300
800
1300
1800
2300
80000
2800
250000
60000
200000 150000
40000
100000 20000
50000
0
0 300
800
1300
1800
2300
2800
23
2800
Midstream
Midstream transect
Upstream Downstream Upstream transect
Clearwater R.
Midstream 24
Horse R.
Iron (A17)
100000
180000
180000 150000 120000 90000 60000 30000 0
80000 60000 40000 20000 0 300
800
1300
1800
2300
150000 120000 90000 60000 30000 0
2800
300
800
1300
1800
2300
2800
300
800
1300
1800
2300
2800
1800
2300
2800
180000
100000 80000
180000
150000
150000
120000
120000
90000
90000
60000
60000
40000
30000
60000 30000 0
0
20000
300 300
800
1300
1800
300
800
1300
1800
2300
800
1300
2800
0 300
800
1300
1800
2300
2800 180000 150000
100000
120000
80000
90000
60000
60000 30000
40000
0 20000 0 300
800
1300
1800
2300
2800
2300
2800
25
Other applications of AF4-UV-ICPMS
Lina Du Poster 181345 Distribution of dissolved trace elements amongst colloidal species in soil solutions under different treatments
Andrew Nagel Poster 18214 Relating the distribution of trace elements amongst colloidal species to toxicity in aquatic systems (Daphnia magna)
Marjan Ghotbizadeh Poster 181871 Spatial variation in the speciation, composition and morphology of trace elements in the lower Athabasca River and its tributaries (with TEM-EDS of AF4 size fractions)
Current Members
Chad Cuss Postdoctoral Fellow
Melissa Dergousoff M.Sc. Candidate
Lina Du M.Sc. Candidate
Tracy Gartner Project Manager
Marjan Ghotbizadeh M.Sc. Candidate
Iain Grant-Weaver Technician
Muhammad Javed (Babar) Postdoctoral Fellow
Karen Lund Administrative Support
Acacia Markov Summer Research Assistant
Andrew Nagel M.Sc. Candidate
Tommy Noernberg Mechanical Engineering Technologist
Samantha Stachiw M.Sc. Candidate
William Shotyk Bocock Chair for Agriculture & the Environment
ACKNOWLEDGEMENTS
28
29
Thank you for your attention!
Additional slides: • Optimization: FFF theory and resolution + multi-element optimization • Visualization of AF4 separation • Routine QA/QC procedures for low LODs and high precision • AF4-UV-ICPMS component diagram • Precision of separation and fractogram deconvolution 30
First-order optimization: estimating ideal field strength for desired linear range Theoretical retention time-size relationship
Shaded box: theoretical linear range of size separation at FS = 0.5 mL min-1 Field strength (mL min-1)
Theoretical linear behaviour at FS = 1.0 mL min-1, to be verified using standards Modified from Von Der Kammer F, Legros S, Larsen EH, Loeschner K, Hofmann T (2011) Separation and characterization of nanoparticles in complex food and environmental samples by field-flow fractionation. Trends in Analytical Chemistry (30):425–436.
31
Multi-element optimization: balancing retention and resolution Field Strength: 1.0 mL min-1 Time: 5 min.
FS: 1.8 mL min-1 T: 5 min.
FS: 1.8 mL min-1 T: 10 min.
FS: 2.7 mL min-1 T: 5 min.
100
78.4% retained
80
DOM
57.3%
36.9%
45.0%
60
Signal (CPS for elements, A254 in mAU for DOM)
40 20 0
400 600
800 1000 1200 1400
400 600
800 1000 1200 1400 400 600
800 1000 1200 1400 400 600
800 1000 1200 1400
Retention time (seconds) 500000 Max ~ 900,000 CPS
400000
Fe
12.9%
21.9%
11.8%
10.5%
300000 200000 100000 0
400 600
800 1000 1200 1400
400 600
800 1000 1200 1400 400 600
800 1000 1200 1400 400 600
800 1000 1200 1400
Retention time (seconds) 120000 100000
0.3%
1.5%
9.1%
1.5%
80000
Mg 60000 40000 20000
Max ~ 900,000 CPS
0
400 600
800 1000 1200 1400
400 600
800 1000 1200 1400 400 600
800 1000 1200 1400 400 600
800 1000 1200 1400
Retention time (seconds) 32
Tip
Asymmetrical flow field-flow fractionation (AF4) step 1: Injection and focussing
Focus
To Detectors
Detector
Tip flow
Focussing flow
< 350–750 𝜇m
300 Da PES membrane Cross flow out (waste)
33
Tip
AF4 step 2: Elution
Focus
To Detectors
Detector
Focussing flow Tip flow
300 Da PES membrane Cross flow out (waste)
34
Routine QA/QC: standard procedures for low LODs, high precision AF4 (daily routine) DOM (SRNOM standard to condition) Blank Size calibration mixture Blank 1 % HNO3 upstream, in cleaning mode Blank Sample 1 Blank Sample 2 Blank . . .
Sample 10
Blank Size calibration mixture Blank
ICPMS (daily routine) • Daily: 5-point calibration using multielement standard (10 ppt to 100 ppb, downstream injection under same flow conditions) • Daily: 2 SRMs to assess recovery (NIST 1640a and SPS SW2, downstream injection, same flow conditions) • Daily: Whole-sample injections of samples to measure analyte recovery (downstream injections)
• Daily: LOD determination to account for changing background Blank Sample 1 Blank . . .
Sample 10 Blank 35
For DOM characterization: 200 ≤ λ ≤ 640 nm, every 0.4 s 0.004” ID PEEK tubing
PN5300 Autosampler (0.3 mL sample loop)
Postnova AF2000 (300-Da PES membrane, 500 µm spacer)
UV/Vis DAD (G4212, Agilent)
Downstream injection valve (high pressure with 0.3 mL sample loop, Rheodyne)
Quadrupole ICPMS (KED mode)
Micro-mixing tee (PEEK, IDEX M-540A)
Injection valve for total concentration analysis and standards Doubledistilled HNO3 to final conc. of 2% (w/w) + 5 𝜇g L-1 In
Absorbance (254 nm)
AF4-UV-ICPMS system diagram 80
60
40
20
0 400
500
600
700
800
900
Time (seconds)
Adjustments/changes • New membranes and system leached with 2% HNO3 (double-distilled) • Glass eluent reservoir and autosampler vials replaced with acidleached polypropylene
36
Triplicate analyses: high reproducibility with statistical fractogram deconvolution Counts per second
40000
56Fe
30000
Peak
Retention time (s)
% area
1
454
13.9
2
591
39.3
3
858
46.8
Retention time (s)
% area
20000
10000
0 400
600
800
1000
1200
1400
1600
1800
Retention time (s)
Counts per second
40000
Peak 30000
1
456
13.4
20000
2
593
38.3
10000
3
883
48.3
Mean ± 1 SD Peak
Retention time (s)
% area
1
455 ± 1
14 ± 0.3
2
593 ± 2
39 ± 0.6
3
872 ± 13
48 ± 0.8
0 400
600
800
1000
1200
1400
1600
1800
Retention time (s)
Counts per second
40000
Peak
Retention time (s)
% area
1
455
14.0
2
594
38.4
3
874
47.5
30000
20000
10000
0 400
600
800
1000
1200
1400
1600
1800
Retention time (s)
37
Triplicate analyses: high reproducibility with statistical fractogram deconvolution 208Pb
Counts per second
180 160
Peak
Retention time (s)
% area
1
454
8.4
2
601
29.4
3
914
62.1
140 120 100 80 60 40 20 0 400
600
800
1000
1200
1400
1600
1800
Retention time (s)
Counts per second
180
Peak
160
Retention time (s)
140 120 100 80 60 40
Mean ± 1 SD
% area
Retention time (s)
% area
1
463
4.2
Peak
2
624
18.4
1
459 ± 5
8 ± 3.3
3
922
77.4
2
611 ± 12
23 ± 5.7
3
906 ± 21
69 ± 7.7
20 0 400
600
800
1000
1200
1400
1600
1800
Retention time (s)
Counts per second
180 160
Peak
Retention time (s)
% area
1
461
10.8
2
608
21.1
3
883
68.1
140 120 100 80 60 40 20 0 400
600
800
1000
1200
1400
1600
1800
Retention time (s)
38
