SUPPLEMENTARY INFORMATION

Co-occurrence Profiles of Trace Elements in Potable Water Systems: A Case Study

Andra S.S.1, K.C. Makris*1, P. Charisiadis1, C.N. Costa2

1 Water and Health Laboratory, Cyprus International Institute for Environmental and Public Health in association with Harvard School of Public Health, Cyprus University of Technology, Limassol, Cyprus

2 Department of Environmental Science and Technology, Cyprus University of Technology, Limassol, Cyprus

* Assistant Professor of Environmental Health, Water and Health Laboratory, Cyprus International Institute for Environmental and Public Health in association with the Harvard School of Public Health, Cyprus University of Technology, Irenes 95, Limassol 3041, Cyprus.

Fax: +357-25002676; Tel: +357-25002398; E-mail:

A1 / B1
A2 / B2
A3 / B3

Figure SI-1. Principal component analysis (PCA) of trace elements in potable waters of Macedonia region in Greece (left panel) and comparison with a US study (right panel). Scores and loadings of PCA for Greece water samples are presented in A1, A2, and A3 representing a combination of three major components (PC 1, 2 and 3) corresponding to a variance of 27.9%, 17.9% and 13.8% from each PC, respectively. Similar representation stands for the US study depicted on the right panel.

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A /
B

Figure SI-2. Relations between median values of trace elements of interest: arsenic in comparison with manganese and copper (A); and manganese in comparison with nickel and copper (B) in the tested Macedonian potable water samples. Concentrations were normalized to percent total for visualizing extent of correlations, and median values were represented.

Table SI-1. Data on selected elemental composition of interest from distribution pipe systems water and pipe solids presented in a US study (Friedman et al. 2010). Data for water samples is presented as is, while average values were used for pipe solids that make a matched-pair with respective utility. Values below method detection limits, and not-available/non-mentioned data were removed and indicated as blank cells in the table.

Distribution System Water / Distribution Pipe Specimen Solids
Utility / Associated / As / Cd / Cr / Ni / Sb / Se / V / Mn / Zn / pH / Sample / As-Mean / Cd-Mean / Cr-Mean / Ni-Mean / Sb-Mean / Se-Mean / V-Mean
Identifier / Samples / (μg/L) / (μg/L) / (μg/L) / (μg/L) / (μg/L) / (μg/L) / (μg/L) / (μg/L) / (μg/L) / Identifier / (μg/g) / (μg/g) / (μg/g) / (μg/g) / (μg/g) / (μg/g) / (μg/g)
W / A-H / 0.19 / 0.58 / 3.65 / 0.43 / 0.23 / 0.04 / 3.1 / 7.7 / W-A / 4.9 / 0.1 / 3.8 / 3.1 / 0.1 / 0.2 / 2.8
W-B
W-C
CL / A, B / 0.35 / 0.005 / 0.18 / 1.66 / 0.33 / 0.64 / 0.06 / 2.4 / 8.2 / CL-A / 12.3 / 0.41 / 3.345 / 5.42 / 0.21 / 0.075 / 22.55
CL-B
CL / C / 1.7 / 0.02 / 0.38 / 0.17 / 0.011 / 0.23 / 0.65 / 0.03 / 28.1 / 8.5 / CL-C / 38.0 / 0.2 / 3.2 / 3.4 / 0.1 / 0.2 / 14.1
CL / D, E / CL-D / 11.5 / 0.4 / 1.5 / 7.4 / 0.1 / 0.1 / 7.0
CL-E
CL / F / 1.4 / 0.005 / 0.58 / 0.28 / 0.035 / 0.34 / 0.72 / 0.4 / 8.3 / CL-F
CL / G / 0.53 / 0.005 / 0.18 / 1.88 / 0.01 / 0.79 / 0.68 / 0.1 / 11.1 / 7.9 / CL-G
SA / A / 5.18 / 0.003 / 0.36 / 0.022 / 0.12 / 0.89 / 23 / 8.1 / SA-A
SA / B, C / 0.75 / 0.013 / 1 / 0.48 / 0.028 / 0.23 / 1.35 / 0.1 / 9.8 / 7.4 / SA-B / 1.7 / 0.1 / 1.5 / 19.4 / 0.1 / 0.1 / 52.3
SA-C
SA / D / 4.95 / 0.008 / 0.49 / 0.37 / 0.535 / 0.14 / 2.02 / 1.2 / 8 / SA-D
SA / E / 4.66 / 0.007 / 0.73 / 0.34 / 0.025 / 0.65 / 0.3 / 8.1 / SA-E
CH / A / 0.61 / 0.012 / 0.25 / 0.23 / 0.122 / 0.18 / 0.95 / 0.3 / 3.6 / 8 / CH-A / 46.8 / 0.1 / 12.5 / 39.1 / 0.21 / 0.19 / 37.4
RW / A, B / 2.2 / 0.007 / 0.39 / 0.049 / 0.35 / 3.42 / 0.5 / 3.9 / 7.1 / RW-A / 138.9 / 1.5 / 78.7 / 83.7 / 0.5 / 0.1 / 422.5
RW-B
IN / A-D / 1.45 / 0.023 / 1.05 / 1.09 / 0.087 / 0.45 / 6.6 / 2.3 / 7.4 / IN-A / 237.5 / 0.4 / 5.1 / 8.5 / 0.1 / 0.1 / 14.5
IN-B
IN-C
IN-D
CC / A-F / 0.5 / 0.004 / 0.57 / 0.36 / 0.012 / 0.64 / 3.9 / 1.6 / 7.6 / CC-A / 258.6 / 5.8 / 57.9 / 189.9 / 0.2 / 3.1 / 85.3
CC-B
CC-C
CC-D
CC-E
CC-F
DN / A-B / 7.8 / DN-A / 11.3 / 1.6 / 3.6 / 3.3 / 0.1 / 1.0 / 11.8
DN-B
CA / A-B / 0.12 / 0.31 / 0.7 / 1.35 / 0.015 / 0.83 / 0.2 / 127 / 7.3 / CA-A / 18.1 / 1.4 / 63.7 / 92.8 / 0.7 / 0.1 / 48.3
CA-B
PC / A-B / 4.24 / 0.306 / 1.11 / 0.91 / 4.21 / 1.72 / 0.23 / 0.02 / 97.3 / 7.6 / PC-A / 870.0 / 19.8 / 139.5 / 421.5 / 5.0 / 0.6 / 33.7
PC-B
WDB / A / 0.7 / 1.1 / 50 / 10 / 7.6 / WDB-A / 46.9 / 34.1 / 0.82 / 330 / 0.2 / 1.25 / 137
WA / A-D / 0.64 / 0.19 / 0.24 / 0.12 / 11.1 / 6 / 7.2 / WA-A / 2.9 / 0.1 / 5.9 / 1.7 / 0.1 / 0.8 / 4.1
WA-B
WA-C
WA-D
B / A, B, D / 1.43 / 0.024 / 0.58 / 0.24 / 0.065 / 0.81 / 0.69 / 0.1 / 1 / 8.1 / B-A / 24.9 / 0.6 / 7.2 / 7.2 / 0.1 / 0.8 / 39.7
B-B
B-D
B / C / 1.61 / 0.036 / 0.6 / 0.39 / 0.129 / 1.03 / 1.65 / 0.8 / 22.3 / 7.8 / B-C
G / A / 0.7 / 0.62 / 0.36 / 0.23 / 0.88 / 0.2 / 7.9 / G-A
G / B / 1.6 / 0.77 / 0.07 / 0.27 / 1.01 / 0.1 / G-B
AZ / A / 0.89 / 0.019 / 4.53 / 4.38 / 0.051 / 1.09 / 1.21 / 29.9 / 4.4 / 7.3 / AZ-A / NM / NM / NM / NM / NM / NM / NM
BC / A, B / 3.6 / 0.023 / 4.24 / 1.45 / 0.072 / 8.32 / 1.21 / 0.1 / 47.2 / 7.2 / BC-A
BC-B
J / A-D, G-J / 2 / 0.54 / 0.12 / 4.5 / 0.08 / 55.4 / 18 / 7.6 / J-(A-D, G-J)
J / E, F / 2 / 1 / 1.2 / 9.1 / 0.08 / 7.8 / 7.6 / J-E,F
NC / A / 1.1 / 0.91 / 0.35 / 0.01 / 0.19 / 0.85 / 30 / 7.2 / NC,A
ST / A / 0.35 / 0.005 / 3.31 / 0.68 / 0.015 / 0.63 / 0.64 / 7.4 / ST-A / 127 / 0.36 / 19.8 / 37.1 / 0.32 / 0.07 / 84.4
ST / B / 0.13 / 0.014 / 2.69 / 1.03 / 0.007 / 0.12 / 0.62 / 7.4 / ST-B
ST / C / 0.06 / 2.43 / 0.86 / 0.006 / 0.13 / 0.44 / 7.5 / ST-C
ST / D / 0.2 / 0.004 / 0.36 / 1.49 / 0.107 / 0.2 / 0.91 / 1.9 / 7.4 / ST-D
K / A-D / 9 / 8 / K-A / 21.6 / 0.1 / 4.4 / 3.1 / 0.1 / 0.3 / 11.8
K-B

Values below method detection limits and those not-available or not-mentioned in Friedman et al (2010) were removed and indicated as blank cells

Table SI-2. Details on the ICP-MS based analytical method performance measures and quality controls§ for the selected trace elements analyses of Greece water samples.

# / Analyte / a) LOD (µg L-1) / QA/QC
b) LOQ (µg L-1)
c) Linearity (µg L-1)
d) Correlation Coefficient (R2)
Spiked Concentration / Standard Reference Material (SRM)
0.5 µg L-1 spike / 1.0 µg L-1 spike / 2.5 µg L-1 spike / 5.0 µg L-1 spike / 10.0 µg L-1 spike / NIST1643e-10x* / NIST1643e-100x**
Mean ± SD
(Recovery%, RSD%)
[n=3] / Mean ± SD
(Recovery%, RSD%)
[n=4] / Mean ± SD
(Recovery%, RSD%)
[n=2] / Mean ± SD
(Recovery%, RSD%)
[n=3] / Mean ± SD
(Recovery, RSD %)
[n=2] / Mean ± SD
(Recovery%, RSD%)
[n=5] / Mean ± SD
(Recovery%, RSD%)
[n=5]
1 / Vanadium (V) / a) 0.005
b) 0.01
c) 0.01-10
d) 0.9999 / 0.52 ± 0.02
(103%, 4%) / 1.04 ± 0.04
(104%, 4%) / 2.63 ± 0.10
(105%, 4%) / 4.86 ± 0.24
(97%, 5%) / 10.4 ± 0.23
(104%, 2%) / 4.24 ± 0.18
(112%, 4%) / 0.45 ± 0.03
(120%, 6%)
2 / Chromium (Cr) / a) 0.005
b) 0.01
c) 0.01-10
d) 0.9999 / 0.45 ± 0.01
(90%, 1%) / 0.99 ± 0.02
(99%, 2%) / 2.57 ± 0.09
(103%, 4%) / 4.92 ± 0.22
(98%, 4%) / 10.2 ± 0.13
(102%, 1%) / 2.29 ± 0.17
(112%, 8%) / 0.29 ± 0.08
(142%, 27%)
3 / Manganese (Mn) / a) 0.02
b) 0.025
c) 0.025-25
d) 0.9999 / 0.44 ± 0.004
(88%, 1%) / 1.01 ± 0.03
(101%, 1%) / 2.65 ± 0.11
(106%, 4%) / 5.10 ± 0.25
(102%, 5%) / 10.4 ± 0.17
(104%, 2%) / 4.16 ± 0.18
(107%, 4%) / 0.44 ± 0.08
(113%, 19%)
4 / Nickel (Ni) / a) 0.005
b) 0.01
c) 0.01-25
d) 0.9997 / 0.36 ± 0.02
(72%, 6%) / 0.86 ± 0.01
(86%, 1%) / 2.57 ± 0.13
(103%, 5%) / 5.17 ± 0.47
(103%, 9%) / 9.11 ± 0.11
(91%, 1%) / 6.38 ± 0.31
(102%, 5%) / 1.34 ± 0.52
(215%, 39%)
5 / Cobalt (Co) / a) 0.005
b) 0.01
c) 0.01-10
d) 0.9999 / 0.49 ± 0.02
(98, 4%) / 0.98 ± 0.02
(98, 2%) / 2.40 ± 0.07
(96, 3%) / 4.67 ± 0.24
(93, 5%) / 9.57 ± 0.02
(96, 0.3%) / 2.88 ± 0.15
(106, 5%) / 0.28 ± 0.02
(102, 6%)
6 / Copper (Cu) / a) 0.025
b) 2.5
c) 2.5-25
d) 0.9931 / ¥ / ¥ / 3.31 ± 0.25
(132%, 10%) / 11.6 ± 0.09
(116%, 1%) / 8.91 ± 0.02
(89%, 0.2%) / ¥ / ¥
7 / Zinc (Zn) / a) 0.025
b) 10
c) 10-1000
d) 0.9999 / ¥ / ¥ / ¥ / ¥ / 11.6 ± 0.09
(116%, 1%) / ¥ / ¥
8 / Arsenic (As) / a) 0.025
b) 0.05
c) 0.05-25
d) 0.9999 / 0.45 ± 0.02
(89%, 3%) / 0.97 ± 0.01
(97%, 1%) / 2.36 ± 0.17
(94%, 7%) / 4.69 ± 0.11
(94%, 2%) / 9.67 ± 0.13
(97%, 1%) / 7.40 ± 0.27
(122%, 4%) / 0.75 ± 0.35
(123%, 46%)
9 / Selenium (Se) / a) 0.025
b) 0.25
c) 0.25-25
d) 0.9999 / 0.35 ± 0.04
(69%, 3%) / 0.89 ± 0.12
(89%, 13%) / 2.19 ± 0.06
(88%, 3%) / 5.50 ± 1.05
(110%, 19%) / 9.57 ± 0.03
(96%, 0.3%) / 1.34 ± 0.12
(112%, 10%) / ¥
10 / Strontium (Sr) / a) 0.005
b) 0.05
c) 0.05-25
d) 0.9998 / 0.58 ± 0.04
(116%, 8%) / 1.07 ± 0.03
(107%, 3%) / 2.79 ± 0.03
(112%, 1%) / 5.06 ± 0.12
(101%, 2%) / 9.52 ± 0.21
(95%, 2%) / 33.4 ± 1.14
(103%, 3%) / 3.42 ± 0.17
(106%, 5%)
11 / Molybdenum (Mo) / a) 0.005
b) 0.01
c) 0.01-25
d) 0.9999 / 0.58 ± 0.04
(116%, 8%) / 0.99 ± 0.02
(99%, 3%) / 2.40 ± 0.02
(96%, 1%) / 4.80 ± 0.03
(96%, 1%) / 9.49 ± 0.35
(95%, 4%) / 12.3 ± 0.20
(102%, 2%) / 1.21 ± 0.02
(100%, 1%)
12 / Cadmium (Cd) / a) 0.01
b) 0.01
c) 0.01-25
d) 0.9999 / 0.50 ± 0.01
(100%, 1%) / 1.03 ± 0.01
(103%, 1%) / 2.54 ± 0.03
(101%, 1%) / 5.00 ± 0.11
(100%, 2%) / 10.0 ± 0.04
(100%, 0.4%) / 0.67 ± 0.01
(103%, 1%) / 0.10 ± 0.05
(147%, 56%)
13 / Antimony (Sb) / a) 0.01
b) 0.01
c) 0.01-25
d) 0.9999 / 0.49 ± 0.01
(98%, 1%) / 1.03 ± 0.02
(103%, 2%) / 2.65 ± 0.02
(106%, 1%) / 5.26 ± 0.30
(105%, 5%) / 10.4 ± 0.13
(104%, 1%) / 6.95 ± 0.21
(119%, 3%) / 0.67 ± 0.03
(115%, 4%)

§ 80-120% range of recovery from QC samples for the study trace elements was considered acceptable. The highlighted recoveries in yellow indicate those few elements that fell out of these criteria from a particular QC; however, we still considered keeping the QC for presentation since it met the criteria for the other elements. In addition, we had other QC samples analyzed in a batch and those that met the acceptance criteria for any given element at all the times indicating the integrity and validity of both method and instrument performance.

* NIST 1643e-10x represents a 10 times dilution of SRM to yield V at 3.786 µg L-1, Cr at 2.04 µg L-1, Mn at 3.897 µg L-1, Ni at 6.241 µg L-1, Co at 2.706 µg L-1, Cu at 2.276 µg L-1, Zn at 7.85 µg L-1, As at 6.045 µg L-1, Se at 1.197 µg L-1, Sr at 32.31 µg L-1, Mo at 12.14 µg L-1, Cd at 0.6568 µg L-1, and Sb at 5.83 µg L-1; concentrations for testing.

** NIST 1643e-100x represents a 100 times dilution of SRM to yield V at 0.3786 µg L-1, Cr at 0.204 µg L-1, Mn at 0.3897 µg L-1, Ni at 0.6241 µg L-1, Co at 0.2706 µg L-1, Cu at 0.2276 µg L-1, Zn at 0.785 µg L-1, As at 0.6045 µg L-1, Se at 0.1197 µg L-1, Sr at 3.231 µg L-1, Mo at 1.214 µg L-1, Cd at 0.06568 µg L-1, and Sb at 0.583 µg L-1; concentrations for testing.

¥ symbol represents concentration of the tested quality controls were below the limit of quantification (or the lower limit of the calibration curve) for the respective analyte, and hence not appropriate for data presentation and further interpretation.

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Table SI-3. Co-presence frequency of trace elements in potable water samples from Macedonia region in Greece.

# / Arsenic pair with a trace Element / Frequency of co-presence (%)*
1 / As + Mo / 99
2 / As + Sr / 99
3 / As + V / 96
4 / As + Sb / 66
5 / As + Se / 27
6 / As + Cr / 27
7 / As + Zn / 32
8 / As + Mn / 14
9 / As + Cu / 12
10 / As + Ni / 11
11 / As + Co / 3

* Frequency of co-presence was calculated based on percent number of water samples (n=74) with concentrations greater than LOQ for any selected trace element par.

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Table SI-4. Correlation coefficients between trace elements of interest analyzed in potable water samples collected from the Macedonia region in Greece, and compared with statistical analysis outcome using raw data from a similar study in US (Friedman et al. 2010).

Macedonia Region, Greece (this Study) / United States (Water Research Foundation; Friedman et al., 2010)
Variable / By variable / Correlation / Count / Significant P / Correlation / Count / Significant P
Cr / V / 0.73 / 74 / <0.00001 / 0.02 / 30 / 0.9230
Mn / V / -0.08 / 74 / 0.5219 / -0.17 / 30 / 0.3713