Herbicides and trace metals in urban waters in Melbourne, Australia (2011-12):

concentrations and potential impact

Supplementary Information

Mayumi Allinson 1, Pei Zhang 2, AnhDuyen Bui 2, Jackie Myers 1,

Vincent Pettigrove1, Gavin Rose 1,2, Scott A Salzman3,Robert Walters4,

Graeme Allinson5,6

1 Centre for Aquatic Pollution Identification and Management (CAPIM), The University of Melbourne, Parkville, Victoria 3010 Australia

2Agriculture Research and Development Division, Department of Economic Development, Jobs, Transport and Resources, Ernest Jones Drive, Macleod, Victoria 3085, Australia

3Department of Information Systems and Business Analytics, Deakin University, PO Box 423, Warrnambool, Victoria 3280 Australia

4Victoria University, Melbourne, Victoria 3011 Australia

5Department of Environment and Primary Industries, DEPI Queenscliff Centre, Queenscliff, Victoria 3225, Australia

6School of Science, RMIT University, Melbourne, Victoria 3001, Australia

SI1. Herbicides: preparation and summary of analytical methods

No one analytical method is appropriate for the measurement of all of the herbicides investigated in this study, so several different methods based on solid-phase extraction (SPE) were used; these SPE methodologies were validated and accredited by the National Association of Testing Authorities, Australia (NATA) to ISO 17025 standard.

Acid herbicides: The pH of water samples (100 mL) was adjusted to pH to 12 with 1M sodium hydroxide solution (NaOH). After being left for 30 minutes for hydrolysis of any ester adducts to the free carboxylate base, the sample was re-adjusted to pH 7 with 1M hydrochloric acid (HCl), before being loaded onto an SPE cartridge, (Oasis Max™ SPE is 500mg, 6mL; Waters Milford, MA, USA pre-conditioned with 10mL MeOH followed by 10mL water). Thereafter, the cartridge was washed with 10mL 50mM sodium acetate, 12mL MeOH, and 12mL dichloromethane (DCM; washes discarded), before target herbicides were eluted with 12mL 5% formic acid. The eluate was evaporated to dryness under nitrogen, before being reconstituted in 0.5mL MeOH/H2O (2:8).

Sulfonylurea herbicides: 250mL water sample was applied onto a C18 cartridge (Bond Elute Mega BE™-C18; 1g; 6mL; Agilent Technologies, Santa Clara, CA, USA; previously conditioned with 10mL MeOH followed by 10mL water). The cartridge was then washed with 10mL deionised water, and the chemicals of interest eluted using 10mL MeOH. The solution obtained was evaporated to dryness under nitrogen before being reconstituted in 0.5 mL MeOH/H2O (2:8).

‘Triazines’ (triazine, uracil, urea, chloroacetanilide and dinitroaniline herbicides): 100 mL of sample was applied to a solid phase extraction (SPE) cartridge (Bond Elute PPL™; 500 mg, 3 ml; from Agilent Technologies, Santa Clara, CA); previously conditioned with 10 mL methanol (MeOH) and 10 mL water), followed by elution with 5mL of acetonitrile. The acetonitrile solution was then in turn inverted into 0.5 mL of 50% water/methanol.

The final extracts from the SPE clean-ups were used in 3 different analysis programs:

  • ‘Triazines’ by liquid chromatography-tandem mass spectrometry (LC-MS/MS; Allinson et al. 2015): atrazine, cyanazine, hexazinone, metribuzin, prometryn, simazine, terbutryn, terbuthylazine, propazine, desisopropylatrazine ,desethylatrazine(also called desisopropyl-simazine and a derivative of the parent compound simazine). Other herbicides included in the triazine screen were bromacil, diuron, linuron, propazine, metolachlor, and pendimethalin.
  • Acid herbicides by LC-MS/MS (Zhang et al. 2014): 2,4-D, MCPA, MCPB, clopyralid, dicamba, fluroxypyr, picloram, triclopyr.
  • Sulfonylurea herbicides by LC-MS/MS (Zhang et al. 2014): bensulfuron-methyl, chlorsulfuron, metsulfuron-methyl, sulfometuron-methyl, triasulfuron, tribenuron-methyl.

SI1.1 Limit of Detection (LOD) and Limit of Reporting (LOR)

Limit of Detection (LOD) is the lowest concentration level of a pure standard that can be detected that is statistically different from a blank with 99% confidence. As part of our method validation, a 99% confidence LOD was calculated by dividing the instrumental response to the lowest standard concentration(effectively the measured area of the peak in the standard chromatogram) by the slope of the calibration curve and then multiplying the product by the ion ratio of the least abundant qualifier ion. Including the ion ratio factor guarantees that the qualifier ion can be detected with 99% confidence. The LOR (limits of reporting) is what can be detected and quantified with 99% confidence in an actual sample. In this case, the minimum area of an actual sample used for LOR calculation that was three times the area of the closest retention time peak in the blank sample.

The LORs for all the herbicides screened in this study are listed in Table SI1. Herbicide concentrations measured in stormwater are listed in Table SI2. Unless otherwise specified, chemical data is reported as g/L. The results were not corrected for recovery, which was determined by spiking randomly selected samples of each analytical batch of water and sediment samples (typically all the 5 sites) with each reported pesticide. Recovery and reproducibility data are listed in Tables 1b-1g.

Table SI1 Herbicides limits of reporting

Sulfonylurea screen * / Triazine herbicide screen
(g/L) / (g/L)
bensulfuron-methyl / 0.01 / atrazine / 0.003
chlorsulfuron / 0.01 / bromacil / 0.005
metsulfuron-methyl / 0.01 / cyanazine / 0.005
sulfometuron-methyl / 0.05 / DEA / 0.005
triasulfuron / 0.01 / DIA / 0.005
tribenuron-methyl / 0.01 / diuron / 0.01
hexazinone / 0.005
Acid herbicide screen / linuron / 0.005
(g/L) / metolachlor / 0.001
2,4-D / 0.005 / metribuzin / 0.01
clopyralid / 0.4 / pendimethalin / 0.005
dicamba / 0.4 / prometryn / 0.005
fluroxypyr / 0.01 / propachlor / 0.005
MCPA / 0.005 / propazine / 0.003
MCPB / 0.01 / simazine / 0.003
picloram / 0.8 / terbutryn / 0.003
triclopyr / 0.02 / terbuthylazine / 0.005

* Except P6 (March 2012) samples, where LOR triasulfuron 0.001; metsulfuron-methyl, 0.002; sulfometuron-methyl 0.002; chlorsulfuron 0.002; tribenuron-methyl 0.01; and bensulfuron-methyl 0.001 g/L

Table SI1b: Triazines screen recovery data
Analytes / Spiking Level (µg/L) / n / Average Recovery / RSD
Atrazine / 0.02 / 8 / 92% / 24%
Atrazine-desethyl / 0.02 / 8 / 64% / 18%
Atrazine-desispopropyl / 0.02 / 8 / 102% / 18%
Cyanazine / 0.02 / 8 / 78% / 26%
Hexazinone / 0.02 / 8 / 77% / 26%
Metribuzin / 0.02 / 8 / 52% / 30%
Prometryn / 0.02 / 8 / 71% / 24%
Simazine / 0.02 / 8 / 105% / 22%
Terbutryn / 0.02 / 8 / 66% / 22%
Bromacil / 0.02-0.5 / 6 / 75% / 15%
Propachlor / 0.02-0.5 / 6 / 69% / 18%
Diuron / 0.02-0.5 / 6 / 90% / 22%
Propazine / 0.02-0.5 / 6 / 81% / 24%
Terbuthylazine / 0.02-0.5 / 6 / 89% / 17%
Metolachlor / 0.02-0.5 / 6 / 81% / 20%
Pendimethalin / 0.02-0.5 / 6 / 80% / 23%
Linuron / 0.02-0.5 / 6 / 97% / 12%
n, number of recovery test; RSD, relative standard deviation of data
Table SI1c: Triazines screen reproducibility (duplicate analysis) results
Analytes / 1st / 2nd / Mean / Diff/Mean
Atrazine-desispopropyl / 0.277 / 0.213 / 0.245 / 13%
Atrazine-desethyl / 0.179 / 0.151 / 0.165 / 9%
Atrzine / 1.75 / 1.55 / 1.65 / 6%
Metribuzin / 1.01 / 0.966 / 0.988 / 2%
Simazine / 1.88 / 1.56 / 1.72 / 9%
Hexazinone / 0.015 / 0.014 / 0.015 / 3%
Terbutryn / 0.002 / 0.002 / 0.002 / 0%
Table SI1d: Sulfonyl urea herbicides recovery data
Analytes / Spiking Level (µg/L) / n / Average Recovery / RSD
Triasulfuron / 0.04-5.2 / 16 / 93% / 14%
Metsulfuron-methyl / 0.04-5.2 / 16 / 103% / 10%
Sulfometuron-methyl / 0.04-5.2 / 16 / 102% / 15%
Chlorsulfuron / 0.04-5.2 / 16 / 101% / 6%
Tribenuron-methyl / 0.04-5.2 / 6 / 77% / 18%
Bensulfuron-methyl / 0.04-5.2 / 15 / 84% / 14%
n, number of recovery test; RSD, relative standard deviation of data
Table SI1e: Sulfonyl urea herbicide screen reproducibility (duplicate analysis) results
Analytes / 1st / 2nd / Mean / Diff/Mean
Metsulfuron methyl / 1.55 / 1.65 / 1.60 / 6%
Chlorsulfuron / 2.40 / 2.79 / 2.60 / 15%
Metsulfuron methyl / 2.16 / 2.32 / 2.24 / 7%
Chlorsulfuron / 4.23 / 4.20 / 4.22 / 1%
Table SI1f: Phenoxy acid herbicide recovery data
Analytes / Spiking Level (µg/L) / n / Average Recovery / RSD
Clorpyralid / 0.02-0.16 / 34 / 82% / 17%
Picloram / 0.02-0.16 / 30 / 74% / 23%
Dicamba / 0.02-0.16 / 27 / 94% / 19%
Fluroxypyr / 0.02-0.16 / 34 / 84% / 15%
2,4-D / 0.02-0.16 / 32 / 90% / 15%
MCPA / 0.02-0.16 / 31 / 97% / 14%
Triclopyr / 0.02-0.16 / 25 / 83% / 18%
MCPB / 0.02-0.16 / 32 / 69% / 18%
n, number of recovery test; RSD, relative standard deviation of data
Table SI1g: Phenoxy acid herbicide screen reproducibility (duplicate analysis) results
Analytes / 1st / 2nd / Mean / Diff/Mean
Dicamba / 0.029 / 0.035 / 0.032 / 19%
2.4-D / 0.004 / 0.008 / 0.006 / 67%
MCPA / 0.059 / 0.053 / 0.056 / 11%
Triclopyr / 0.02 / 0.014 / 0.017 / 35%
Clopyralid / 0.012 / 0.013 / 0.013 / 8%
Dicamba / 0.031 / 0.035 / 0.033 / 12%
Fluroxypyr / 0.006 / 0.006 / 0.006 / 0%
2.4-D / 0.009 / 0.007 / 0.008 / 25%
MCPA / 0.001 / 0.001 / 0.001 / 0%
Triclopyr / 0.035 / 0.037 / 0.036 / 6%

Table SI 2 Herbicides data

October 2011: Triazine herbicide screen

Site # / DIA / DEA / Bro / Met / Sim / Hex / Cya / Prop / Atr / Diu / Pro / Ter / Meto / Prom / Terb / Pen / Lin
(µg/L)
34 / 0.009 / ND / ND / ND / 0.031 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
202 / ND / ND / ND / ND / 0.011 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
204 / 0.033 / ND / ND / ND / 0.12 / ND / ND / ND / 0.005 / 0.012 / ND / ND / ND / ND / 0.002 / ND / ND
205 / 0.011 / ND / ND / ND / 0.052 / ND / ND / ND / 0.008 / 0.021 / ND / ND / 0.001 / ND / ND / ND / ND
316 / 0.096 / 0.037 / ND / ND / 0.32 / 0.015 / ND / ND / 0.162 / 0.087 / 0.004 / ND / 0.289 / 0.011 / ND / ND / ND
LOR / 0.005 / 0.005 / 0.005 / 0.01 / 0.003 / 0.005 / 0.005 / 0.005 / 0.003 / 0.01 / 0.003 / 0.005 / 0.001 / 0.005 / 0.003 / 0.005 / 0.005

LOR, limit of reporting; ND, not detected; DIA, desisopropyl atrazine; DEA, desethyl atrazine; Bro, bromacil; Met, metribuzin; Sim, simazine, Hex, hexazinone; Cya, cyanazine; Prop, propachlor; Atr, atrazine; Diu, diuron; Pro, propazine; Ter, terbuthylazine; Meto, metolachlor, Prom, prometryn; Terb, terbutryn, Pen, pendimethalin; Lin, linuron.

October 2011: Acid herbicide screen

Site # / Clopyralid / Picloram / Dicamba / Fluroxypyr / 2,4-D / MCPA / MCPB / Triclopyr
(µg/L)
34 / ND / ND / ND / ND / 0.025 / 0.006 / ND / ND
202 / ND / ND / ND / ND / 0.010 / 0.007 / ND / ND
204 / ND / ND / ND / ND / 0.003 / 0.003 / ND / ND
205 / 0.40 / ND / ND / ND / 0.013 / 0.017 / ND / ND
316 / ND / ND / ND / ND / 0.008 / 0.002 / ND / 0.03
LOR / 0.4 / 0.8 / 0.4 / 0.01 / 0.005 / 0.005 / 0.01 / 0.02

LOR, limit of reporting; ND, not detected

Table SI 2 (continued)

October 2011: Sulfonyl urea herbicide screen

Site # / Triasulfuron / Metsulfuron-methyl / Sulfometuron-methyl / Chlorsulfuron / Tribenuron-methyl / Bensulfuron-methyl
(µg/L)
34 / ND / ND / ND / ND / ND / ND
202 / ND / ND / ND / ND / ND / ND
204 / ND / 0.01 / 0.07 / ND / ND / ND
205 / ND / ND / ND / ND / ND / ND
316 / ND / 0.01 / ND / ND / ND / ND
LOR / 0.02 / 0.02 / 0.05 / 0.02 / 0.02 / 0.02

LOR, limit of reporting; ND, not detected

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November 2011: Triazine herbicide screen

Site # / DIA / DEA / Bro / Met / Sim / Hex / Cya / Prop / Atr / Diu / Prom / Ter / Meto / Prom / Terb / Pen / Lin
(µg/L)
34 / 0.004 / ND / ND / ND / 0.014 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
202 / 0.026 / ND / ND / ND / 0.18 / ND / ND / ND / 0.004 / 0.042 / ND / ND / ND / ND / ND / ND / ND
204 / 0.064 / ND / ND / ND / 0.24 / ND / ND / ND / ND / 0.045 / ND / ND / 0.001 / ND / 0.012 / ND / ND
205 / 0.020 / ND / ND / ND / 0.11 / ND / ND / ND / 0.002 / 0.008 / ND / ND / ND / ND / ND / ND / ND
316 / 0.037 / 0.021 / ND / ND / 0.21 / 0.006 / ND / ND / 0.78 / 0.043 / 0.007 / ND / 0.23 / ND / 0.003 / ND / ND
LOR / 0.005 / 0.005 / 0.005 / 0.01 / 0.003 / 0.005 / 0.005 / 0.005 / 0.003 / 0.01 / 0.003 / 0.005 / 0.001 / 0.005 / 0.003 / 0.005 / 0.005

LOR, limit of reporting; ND, not detected; DIA, desisopropyl atrazine; DEA, desethyl atrazine; Bro, bromacil; Met, metribuzin; Sim, simazine, Hex, hexazinone; Cya, cyanazine; Prop, propachlor; Atr, atrazine; Diu, diuron; Pro, propazine; Ter, terbuthylazine; Meto, metolachlor, Prom, prometryn; Terb, terbutryn, Pen, pendimethalin; Lin, linuron.

Table SI 2 (continued)

November 2011: Acid herbicide screen

Site # / Clopyralid / Picloram / Dicamba / Fluroxypyr / 2,4-D / MCPA / MCPB / Triclopyr
(µg/L)
34 / ND / ND / ND / ND / 0.007 / ND / ND / ND
202 / ND / ND / ND / ND / 0.017 / 0.009 / ND / ND
204 / ND / ND / ND / ND / 0.016 / ND / ND / ND
205 / 0.15 / ND / ND / ND / 0.018 / 0.078 / ND / ND
316 / ND / ND / ND / ND / 0.12 / 0.039 / ND / 0.02
LOR / 0.4 / 0.8 / 0.4 / 0.01 / 0.005 / 0.005 / 0.01 / 0.02

LOR, limit of reporting; ND, not detected

November 2011: Sulfonyl urea herbicide screen ()

Site # / Triasulfuron / Metsulfuron-methyl / Sulfometuron-methyl / Chlorsulfuron / Tribenuron-methyl / Bensulfuron-methyl
(µg/L)
34 / ND / ND / ND / ND / ND / ND
202 / ND / ND / ND / ND / ND / ND
204 / ND / 0.02 / ND / ND / ND / ND
205 / ND / ND / ND / ND / ND / ND
316 / ND / ND / ND / ND / ND / ND
LOR / 0.02 / 0.02 / 0.05 / 0.02 / 0.02 / 0.02

LOR, limit of reporting; ND, not detected

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Table SI 2 (continued)

December 2011: Triazine herbicide screen

Site # / DIA / DEA / Bro / Met / Sim / Hex / Cya / Prop / Atr / Diu / Prom / Ter / Meto / Prom / Terb / Pen / Lin
(µg/L)
34 / 0.007 / 0.002 / ND / ND / 0.011 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
202 / 0.005 / ND / ND / ND / 0.017 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
204 / 0.002 / ND / ND / ND / 0.005 / ND / ND / ND / ND / ND / ND / ND / ND / ND / 0.033 / ND / ND
205 / ND / ND / ND / ND / 0.002 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
316 / 0.002 / ND / ND / ND / 0.004 / 0.009 / ND / ND / 0.010 / ND / ND / ND / 0.002 / ND / ND / ND / ND
LOR / 0.005 / 0.005 / 0.005 / 0.01 / 0.003 / 0.005 / 0.005 / 0.005 / 0.003 / 0.01 / 0.003 / 0.005 / 0.001 / 0.005 / 0.003 / 0.005 / 0.005

LOR, limit of reporting; ND, not detected; DIA, desisopropyl atrazine; DEA, desethyl atrazine; Bro, bromacil; Met, metribuzin; Sim, simazine, Hex, hexazinone; Cya, cyanazine; Prop, propachlor; Atr, atrazine; Diu, diuron; Pro, propazine; Ter, terbuthylazine; Meto, metolachlor, Prom, prometryn; Terb, terbutryn, Pen, pendimethalin; Lin, linuron.

December 2011: Acid herbicide screen

Site # / Clopyralid / Picloram / Dicamba / Fluroxypyr / 2,4-D / MCPA / MCPB / Triclopyr
(µg/L)
34 / ND / ND / ND / ND / 0.005 / 0.269 / ND / ND
205 / ND / ND / ND / ND / 0.024 / 0.148 / ND / ND
202 / ND / ND / ND / ND / 0.010 / 0.010 / ND / ND
204 / ND / ND / ND / ND / 0.011 / 0.008 / ND / ND
316 / ND / ND / ND / ND / 0.37 / 0.059 / ND / 0.062
LOR / 0.4 / 0.8 / 0.4 / 0.01 / 0.005 / 0.005 / 0.01 / 0.02

LOR, limit of reporting; ND, not detected

Table SI 2 (continued)

December 2011: Sulfonyl urea herbicide screen

Site # / Triasulfuron / Metsulfuron-methyl / Sulfometuron-methyl / Chlorsulfuron / Tribenuron-methyl / Bensulfuron-methyl
(µg/L)
34 / ND / ND / ND / ND / ND / ND
202 / ND / 0.01 / ND / ND / ND / ND
204 / ND / 0.02 / ND / ND / ND / ND
205 / ND / ND / ND / ND / ND / ND
316 / ND / 0.02 / 0.05 / ND / ND / ND
LOR / 0.01 / 0.01 / 0.05 / 0.01 / 0.01 / 0.01

LOR, limit of reporting; ND, not detected

************************************

January 2012: Triazine herbicide screen

Site # / DIA / DEA / Bro / Met / Sim / Hex / Cya / Prop / Atr / Diu / Prom / Ter / Meto / Prom / Terb / Pen / Lin
(µg/L)
34 / 0.032 / ND / ND / ND / 0.098 / ND / ND / ND / 0.002 / 0.008 / ND / ND / ND / ND / ND / ND / ND
202 / 0.002 / ND / ND / ND / 0.007 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
204 / 0.010 / ND / ND / ND / 0.038 / ND / ND / ND / 0.006 / 0.017 / ND / ND / 0.002 / ND / 0.024 / ND / ND
205 / 0.022 / ND / ND / ND / 0.11 / ND / ND / ND / 0.004 / 0.025 / ND / ND / 0.001 / ND / ND / ND / ND
316 / 0.019 / ND / ND / 0.01 / 0.098 / ND / ND / ND / 0.047 / 0.009 / ND / ND / 0.014 / ND / ND / ND / ND
LOR / 0.005 / 0.005 / 0.005 / 0.01 / 0.003 / 0.005 / 0.005 / 0.005 / 0.003 / 0.01 / 0.003 / 0.005 / 0.001 / 0.005 / 0.003 / 0.005 / 0.005

LOR, limit of reporting; ND, not detected; DIA, desisopropyl atrazine; DEA, desethyl atrazine; Bro, bromacil; Met, metribuzin; Sim, simazine, Hex, hexazinone; Cya, cyanazine; Prop, propachlor; Atr, atrazine; Diu, diuron; Pro, propazine; Ter, terbuthylazine; Meto, metolachlor, Prom, prometryn; Terb, terbutryn, Pen, pendimethalin; Lin, linuron.

Table SI 2 (continued)

January 2012: Acid herbicide screen

Site # / Clopyralid / Picloram / Dicamba / Fluroxypyr / 2,4-D / MCPA / MCPB / Triclopyr
(µg/L)
34 / ND / ND / ND / ND / 0.061 / ND / ND / ND
202 / ND / ND / ND / ND / 0.027 / 0.005 / ND / ND
204 / ND / ND / ND / ND / 0.040 / 0.004 / ND / ND
205 / ND / 1.3 / ND / ND / 0.052 / 0.13 / ND / 1.4
316 / ND / ND / ND / ND / 0.089 / 0.006 / ND / ND
LOR / 0.4 / 0.8 / 0.4 / 0.01 / 0.005 / 0.005 / 0.01 / 0.02

LOR, limit of reporting; ND, not detected

January 2012: Sulfonyl urea herbicide screen

Site # / Triasulfuron / Metsulfuron-methyl / Sulfometuron-methyl / Chlorsulfuron / Tribenuron-methyl / Bensulfuron-methyl
(µg/L)
34 / ND / ND / ND / ND / ND / ND
202 / ND / ND / ND / ND / ND / ND
204 / ND / 0.031 / ND / ND / ND / ND
205 / ND / ND / ND / ND / ND / ND
316 / ND / 0.005 / ND / ND / ND / ND
LOR / 0.01 / 0.01 / 0.05 / 0.01 / 0.01 / 0.01

LOR, limit of reporting; ND, not detected

************************************

Table SI 2 (continued)

February 2012: Triazine herbicide screen

Site # / DIA / DEA / Bro / Met / Sim / Hex / Cya / Prop / Atr / Diu / Prom / Ter / Meto / Prom / Terb / Pen / Lin
(µg/L)
34 / 0.17 / ND / ND / ND / 2.2 / ND / ND / ND / 0.007 / 0.02 / ND / ND / ND / ND / ND / ND / ND
202 / 0.008 / ND / ND / ND / 0.065 / ND / ND / ND / 0.004 / 0.06 / ND / ND / ND / ND / 0.003 / ND / ND
204 / 0.011 / ND / ND / ND / 0.070 / ND / ND / ND / ND / 0.05 / ND / ND / ND / ND / 0.017 / ND / ND
205 / 0.55 / ND / ND / ND / 4.0 / ND / ND / ND / 0.008 / 0.03 / ND / ND / ND / ND / 0.004 / ND / ND
316 / 0.13 / 0.04 / ND / ND / 1.4 / 0.014 / ND / ND / 0.21 / 0.04 / 0.004 / ND / 0.34 / ND / ND / ND / ND
LOR / 0.005 / 0.005 / 0.005 / 0.01 / 0.003 / 0.005 / 0.005 / 0.005 / 0.003 / 0.01 / 0.003 / 0.005 / 0.001 / 0.005 / 0.003 / 0.005 / 0.005

LOR, limit of reporting; ND, not detected; DIA, desisopropyl atrazine; DEA, desethyl atrazine; Bro, bromacil; Met, metribuzin; Sim, simazine, Hex, hexazinone; Cya, cyanazine; Prop, propachlor; Atr, atrazine; Diu, diuron; Pro, propazine; Ter, terbuthylazine; Meto, metolachlor, Prom, prometryn; Terb, terbutryn, Pen, pendimethalin; Lin, linuron.

February 2012: Acid herbicide screen

Site # / Clopyralid / Picloram / Dicamba / Fluroxypyr / 2,4-D / MCPA / MCPB / Triclopyr
(µg/L)
34 / ND / ND / ND / ND / 0.102 / 0.009 / ND / ND
202 / ND / ND / ND / ND / 0.032 / 0.009 / ND / ND
204 / ND / ND / ND / ND / 0.039 / 0.008 / ND / ND
205 / ND / ND / ND / ND / 0.20 / 0.044 / ND / 0.12
316 / ND / ND / ND / ND / 2.3 / 0.154 / ND / 0.14
LOR / 0.4 / 0.8 / 0.4 / 0.01 / 0.005 / 0.005 / 0.01 / 0.02

LOR, limit of reporting; ND, not detected

Table SI 2 (continued)

February 2012: Sulfonyl urea herbicide screen

Site # / Triasulfuron / Metsulfuron-methyl / Sulfometuron-methyl / Chlorsulfuron / Tribenuron-methyl / Bensulfuron-methyl
(µg/L)
34 / ND / ND / ND / ND / ND / ND
202 / ND / ND / ND / ND / ND / ND
204 / ND / 0.02 / ND / ND / ND / ND
205 / ND / ND / ND / ND / ND / ND
316 / ND / ND / ND / ND / ND / ND
LOR / 0.01 / 0.01 / 0.05 / 0.01 / 0.01 / 0.01

LOR, limit of reporting; ND, not detected

************************************

March 2012: Triazine herbicide screen

Site # / DIA / DEA / Bro / Met / Sim / Hex / Cya / Pro / Atr / Diu / Prop / Ter / Meto / Prom / Terb / Pen / Lin
(µg/L)
34 / 0.032 / ND / ND / ND / 0.050 / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND / ND
202 / 0.17 / ND / ND / ND / 4.4 / ND / ND / ND / ND / 0.083 / ND / ND / ND / ND / ND / ND / ND
204 / 0.062 / ND / ND / ND / 0.24 / ND / ND / ND / ND / 0.007 / ND / ND / ND / ND / 0.31 / ND / ND
205 / 0.069 / ND / ND / ND / 0.40 / ND / ND / ND / ND / 0.016 / ND / ND / ND / ND / ND / ND / ND
316 / 0.25 / ND / ND / ND / 0.74 / 0.030 / ND / ND / 0.12 / 0.029 / ND / ND / 0.30 / ND / ND / ND / ND
LOR / 0.005 / 0.005 / 0.005 / 0.01 / 0.003 / 0.005 / 0.005 / 0.005 / 0.003 / 0.01 / 0.003 / 0.005 / 0.001 / 0.005 / 0.003 / 0.005 / 0.005

LOR, limit of reporting; ND, not detected; DIA, desisopropyl atrazine; DEA, desethyl atrazine; Bro, bromacil; Met, metribuzin; Sim, simazine, Hex, hexazinone; Cya, cyanazine; Prop, propachlor; Atr, atrazine; Diu, diuron; Pro, propazine; Ter, terbuthylazine; Meto, metolachlor, Prom, prometryn; Terb, terbutryn, Pen, pendimethalin; Lin, linuron.

Table SI 2 (continued)

March 2012: Acid herbicide screen

Site # / Clopyralid / Picloram / Dicamba / Fluroxypyr / 2,4-D / MCPA / MCPB / Triclopyr
(µg/L)
34 / ND / ND / ND / ND / 0.005 / ND / ND / 0.023
202 / ND / ND / ND / ND / 0.006 / 0.013 / ND / 0.035
204 / ND / ND / ND / ND / ND / ND / ND / ND
205 / ND / ND / ND / ND / ND / 0.009 / ND / 0.11
316 / ND / ND / ND / ND / 0.072 / 0.015 / ND / 0.039
LOR / 0.4 / 0.8 / 0.4 / 0.01 / 0.005 / 0.005 / 0.01 / 0.02

LOR, limit of reporting; ND, not detected

March 2012: Sulfonyl urea herbicide screen

Site # / Triasulfuron / Metsulfuron-methyl / Sulfometuron-methyl / Chlorsulfuron / Tribenuron-methyl / Bensulfuron-methyl
34 / ND / ND / ND / ND / ND / ND
202 / ND / ND / 0.073 / ND / ND / ND
204 / ND / 0.032 / 0.005 / ND / ND / ND
205 / ND / ND / ND / ND / ND / ND
316 / 0.001 / 0.014 / 0.006 / ND / ND / ND

LOR, limit of reporting; ND, not detected

SI3.1Triazines LC-MS/MS Screen in Water

LC-MS/MS conditions

Triple Quadrupole System: / Waters Micromass Quattro Micro
Source Temp: / Electrospray Ionisation, 120˚C
Desolvation Temp: / 250˚C
Gas Flow: / Desolvation: 500L/hr, Cone: 50L/hr
Capillary (kv): / 3.2
Cone (v): / 25
Collision Energy: / Optimized for each compound
HPLC Column: / Kinetex 2.6µ C18 100A, 50 x 2.10mm
Mobile Phase A: / 20% Methanol in 5 mM ammonium acetate
Mobile Phase B: / 90% Methanol in 5 mM ammonium acetate

Mobile Phase Gradient

Time (min.) / %A / %B / Flow (mL/min.)
0.0 / 90.0 / 10.0 / 0.2
6.0 / 0.0 / 100.0 / 0.2
11.0 / 0.0 / 100.0 / 0.2
12.0 / 90.0 / 10.0 / 0.2
14.0 / 90.0 / 10.0 / 0.2

Triazine Screen Components and Mass Transitions

Compound / Mode / Transitions / Dwell (s) / Cone (V) / Collision Energy (V) / Delay (s) / Retention time (min)
Atrazine- desisopropyl / P / 174.0>68.0 / 0.1 / 28 / 24 / 0.02 / 2.67
174.0>104.0 / 0.1 / 28 / 24 / 0.02
Atrazine- desethyl / P / 188.0>104.0 / 0.1 / 28 / 24 / 0.02 / 4.33
188.0>146.0 / 0.1 / 28 / 24 / 0.02
Atrazine- 2-hydroxy / P / 198.0>86.0 / 0.1 / 28 / 24 / 0.02 / 5.23
198.0>156.0 / 0.1 / 28 / 24 / 0.02
Cyanazine / P / 241.0>96.0 / 0.1 / 28 / 24 / 0.02 / 6.01
241.0>214.0 / 0.1 / 28 / 24 / 0.02
Metribuzin / P / 215.0>84.0 / 0.1 / 28 / 24 / 0.02 / 6.02
215.0>187.0 / 0.1 / 28 / 24 / 0.02
Compound / Mode / Transitions / Dwell (s) / Cone (V) / Collision Energy (V) / Delay (s) / Retention time (min)
Simazine / P / 202.0>96.0 / 0.1 / 28 / 24 / 0.02 / 6.23
202.0>104.0 / 0.1 / 28 / 24 / 0.02
Hexazinone / P / 253.0>71.0 / 0.2 / 22 / 18 / 0.02 / 6.24
253.0>171.0 / 0.1 / 22 / 18 / 0.02
Atrazine / P / 216.0>96.0 / 0.1 / 28 / 24 / 0.02 / 7.02
216.0>174.0 / 0.1 / 28 / 24 / 0.02
Prometryn / P / 242.07>158.47 / 0.1 / 34 / 24 / 0.02 / 8.41
242.07>200.61 / 0.1 / 34 / 18 / 0.02
Terbutryn / P / 242.07>71.14 / 0.1 / 28 / 30 / 0.02 / 8.57
242.07>186.56 / 0.1 / 28 / 18 / 0.02
Bromacil / P / 260.76>188.14 / 0.1 / 22 / 30 / 0.02 / 6.17
260.76>205.30 / 0.1 / 22 / 12 / 0.02
Propachlor / P / 211.87>94.16 / 0.1 / 28 / 24 / 0.02 / 7.13
211.87>170.32 / 0.1 / 28 / 12 / 0.02
Diuron / P / 232.82>72.06 / 0.1 / 28 / 18 / 0.02 / 7.36
232.82>160.29 / 0.1 / 28 / 24 / 0.02
Liuron / P / 248.75>160.28 / 0.1 / 22 / 18 / 0.02 / 7.93
248.75>182.33 / 0.1 / 22 / 12 / 0.02
Propazine / P / 229.88>146.31 / 0.1 / 28 / 24 / 0.02 / 7.77
229.88>188.44 / 0.1 / 28 / 18 / 0.02
Terbuthylaine / P / 229.88>96.16 / 0.1 / 28 / 24 / 0.02 / 7.95
229.88>174.38 / 0.1 / 28 / 18 / 0.02
Metolachlor / P / 283.88>176.45 / 0.1 / 22 / 24 / 0.02 / 8.47
283.88>252.51 / 0.1 / 22 / 12 / 0.02
Pendimethalin / P / 281.99>194.45 / 0.1 / 16 / 18 / 0.02 / 10.06
281.99>212.43 / 0.1 / 16 / 12 / 0.02

SI3.2 Acid herbicides

LC-MS/MS Conditions

Triple Quadrapole System: / Varian 1200L or equivalent
Ionisation: / Electrospray Ionisation
Collision Gas: / Argon at 1.5mTorr
Collision Energy: / Optimised for each compound
Dry Gas/Temperature: / 300oC
Needle Voltage: / 5000V
Shield Voltage: / 600V
HPLC Column: / Varian Polaris 5µ C18, 150x 2.0mm
Guard Column: / Phenomenex C18
Mobile phase: / A:20%MeOH/80%0.1%Formic acid (with addition of 0.32g ammonium formate per liter)
B:90%MeOH/10%0.1%Formic acid (with addition of 0.32g ammonium formate per liter)

Mobile Phase Gradient

Time / %A / %B / Flow rate
0:00 / 70 / 30 / 0.2
1:00 / 70 / 30 / 0.2
5:00 / 0 / 100 / 0.2
10:00 / 0 / 100 / 0.2
10.06 / 70 / 30 / 0.2
15:00 / 70 / 30 / 0.2

MS Scan Method

Ion Source:ESI

Scan Mode:Centroid

SIM Width:0.700 amu

Components and Mass Transitions

Compound / Mode / Transitions / Capillary CID / Collision Energy (V) / Retention time
(min)
Clopyralid / Negative / 190.3>146.0 / 35 / 8 / 3.01
192.8>148.0 / 35 / 8
Picloram / Negative / 239.5>195.0 / 30 / 10 / 3.30
241.7>197.0 / 30 / 9
Dicamba / Negative / 219.3>175.0 / 20 / 6.5 / 5.91
221.8>177.0 / 20 / 6.5
Fluroxypr / Negative / 253.3>195.0 / 40 / 11.5 / 7.03
255.7>197.0 / 40 / 12
2,4-D / Negative / 219.4>161.0 / 40 / 12 / 8.18
221.7>163.0 / 40 / 12
MCPA / Negative / 199.4>141.0 / 40 / 13.5 / 8.31
201.7>143.0 / 40 / 13
Triclopyr / Negative / 254.5>196.0 / 30 / 10.5 / 8.48
254.5>218.0 / 30 / 6
MCPB / Negative / 227.3>141.0 / 20 / 9 / 9.29
229.2>143.0 / 20 / 10

SI3.3Sulfonylureas LC-MS/MS Screen in Water

LC-MS/MS Conditions

Triple Quadrapole System: / Varian 1200L or equivalent
Ionisation: / Electrospray Ionisation
Collision Gas: / Argon at 1.5mTorr
Collision Energy: / Optimised for each compound
Dry Gas/Temperature: / 250oC
Needle Voltage: / 5000V
Shield Voltage: / 600V
HPLC Column: / Varian Polaris 5µ C18, 150x 2.0mm
Guard Column: / Phenomenex C18
Mobile phase: / A:20%MeOH/80%0.1%Formic acid (with addition of 0.32g ammonium formate per liter)
B:90%MeOH/10%0.1%Formic acid (with addition of 0.32g ammonium formate per liter)

Mobile Phase Gradient

Time

/

%A

/

%B

/

Flow rate

0:00

/

100.0

/

0.0

/

0.2

5:00

/

68:0

/

32.0

/

0.2

19:00

/

68:0

/

32.0

/

0.2

23:00

/

15.0

/

85.0

/

0.2

28:00

/

15.0

/

85.0

/

0.2

28:06

/

0.0

/

100.0

/

0.2

32:00

/

0.0

/

100.0

/

0.2

32:01

/

100.0

/

0.0

/

0.2

39:00

/

100.0

/

0.0

/

0.2

MS Scan Method

Ion Source:ESI

Scan Mode:Centroid

SIM Width:0.700 amu

Components and Mass Transitions

COMPOUND

/

CAPILLARY VOLTAGE

/

MODE

/

TRANSITIONS

/

COLLISION ENERGY

/

TRANSITIONS

/

COLLISION ENERGY

Sulfometuron Methyl

/

40

/

-Ve

/

363.6>122.0

/

21.5

/

363.6>182.0

/

13.0

Metsulfuron Methyl

/

40

/

- Ve

/

380.1>139.0

/

16.0

/

380.1>214.0

/

9.0

Triasulfuron

/

35

/

- Ve

/

400.7>139.0

/

17.0

/

400.7>198.0

/

9.5

Chlorsulfuron

/

40

/

- Ve

/

356.5>138.0

/

15.5

/

356.5>189.0

/

10.5

Tribenuron Methyl

/

25

/

+ Ve

/

396.7>155.0

/

11.0

/

396.7>181.0

/

20.5

Bensulfuron Methyl

/

40

/

+ Ve

/

411.7>149.0

/

17.5

/

411.7>182.0

/

17.5

Table SI4Physico-chemical and nutrients data

October 2011

Site # / Analyte
T / pH / EC / NH3 / NO2/3- / TKN / TN / TP / SS / HO-alk / CO32- / HCO3- / Alk
(°C) / S/cm) / (mg/L)
34 / 12.3 / 7.3 / 1074 / - / 0.43 / ND / 0.4 / 0.05 / - / - / - / - / -
202 / 21.2 / 8.5 / 94 / - / 0.07 / 0.3 / 0.4 / 0.09 / - / - / - / - / -
204 / 14.4 / 7.6 / 308 / - / 0.74 / ND / 0.7 / 0.6 / - / - / - / - / -
205 / 14.4 / 6.6 / 227 / - / ND / 0.5 / 0.5 / 0.19 / - / - / - / - / -
316 / 19.8 / 7.4 / 557 / - / 0.25 / 0.6 / 0.8 / 0.46 / - / - / - / - / -
LOR / 0.01 / 0.01 / 0.1 / 0.1 / 0.01 / 5 / 1 / 1 / 1 / 1

LOR, limit of reporting; ND, not detected (< LOR); -, not measured; T, temperature; EC, electrical conductivity; NH3, Ammonia Nitrogen; NO2/3-, Nitrite + Nitrate as N; TKN, Total Kjeldahl Nitrogen as N; TN, Total Nitrogen as N; TP, Total Phosphorus as P; SS, suspended solids; HO-alk, hydroxide alkalinity as CaCO3; CO32-, carbonate alkalinity as CaCO3; HCO3-, bicarbonate alkalinity as CaCO3; Alk, total alkalinity as CaCO3.

November 2011

Site # / Analyte
T / pH / EC / NH3 / NO2/3- / TKN / TN / TP / SS / HO-alk / CO32- / HCO3- / Alk
(°C) / S/cm) / (mg/L)
34 / 18.5 / 7.2 / 409 / 0.03 / 0.29 / 0.3 / 0.6 / ND / 14 / ND / ND / 93 / 93
202 / 23.5 / 6.6 / 83 / 0.43 / 0.22 / 0.8 / 1 / 0.16 / ND / ND / ND / 42 / 42
204 / 18.1 / 7.9 / 364 / 0.09 / 1.27 / 0.7 / 2 / 0.81 / 16 / ND / ND / 146 / 146
205 / 17.8 / 6.8 / 166 / 0.29 / 0.3 / 1.1 / 1.4 / 0.09 / 37 / ND / ND / ND / ND
316 / 17.2 / 6.9 / 160 / 0.16 / 0.86 / 0.9 / 1.8 / 0.43 / 30 / ND / ND / 51 / 51
LOR / 0.01 / 0.01 / 0.1 / 0.1 / 0.01 / 5 / 1 / 1 / 1 / 1

LOR, limit of reporting; ND, not detected (< LOR); -, not measured; T, temperature; EC, electrical conductivity; NH3, Ammonia Nitrogen; NO2/3-, Nitrite + Nitrate as N; TKN, Total Kjeldahl Nitrogen as N; TN, Total Nitrogen as N; TP, Total Phosphorus as P; SS, suspended solids; HO-alk, hydroxide alkalinity as CaCO3; CO32-, carbonate alkalinity as CaCO3; HCO3-, bicarbonate alkalinity as CaCO3; Alk, total alkalinity as CaCO3.

Table SI 4(continued)

December 2011

Site # / Analyte
T / pH / EC / NH3 / NO2/3- / TKN / TN / TP / SS / HO-alk / CO32- / HCO3- / Alk
(°C) / S/cm) / (mg/L)
34 / 18.9 / 7.3 / 654 / 0.06 / 0.19 / 0.9 / 1.1 / 0.2 / 14 / <1 / 15 / 120 / 135
202 / 22.4 / 6.6 / 86 / 0.1 / 0.11 / 1.1 / 1.2 / 0.2 / <5 / <1 / <1 / 43 / 43
204 / 18.9 / 9.0 / 595 / 0.1 / 1.75 / 0.9 / 2.6 / 0.73 / 21 / <1 / 19 / 158 / 177
205 / 20.2 / 7.2 / 110 / 0.33 / 0.78 / 0.7 / 1.5 / 0.11 / 66 / <1 / 43 / 16 / 59
316 / 17.4 / 7.8 / 334 / 0.21 / 0.79 / 1 / 1.8 / 0.25 / 38 / <1 / <1 / 95 / 95
LOR / 0.01 / 0.01 / 0.1 / 0.1 / 0.01 / 5 / 1 / 1 / 1 / 1

LOR, limit of reporting; ND, not detected (< LOR); -, not measured; T, temperature; EC, electrical conductivity; NH3, Ammonia Nitrogen; NO2/3-, Nitrite + Nitrate as N; TKN, Total Kjeldahl Nitrogen as N; TN, Total Nitrogen as N; TP, Total Phosphorus as P; SS, suspended solids; HO-alk, hydroxide alkalinity as CaCO3; CO32-, carbonate alkalinity as CaCO3; HCO3-, bicarbonate alkalinity as CaCO3; Alk, total alkalinity as CaCO3

January 2012

Site # / Analyte
T / pH / EC / NH3 / NO2/3- / TKN / TN / TP / SS / HO-alk / CO32- / HCO3- / Alk
(°C) / S/cm) / (mg/L)
34 / 18.6 / 7.2 / 822 / 0.04 / 0.07 / 0.5 / 0.6 / 0.08 / 576 / ND / ND / 114 / 114
202 / 22.3 / 6.5 / 110 / 0.51 / 0.04 / 1.6 / 1.6 / 0.41 / 92 / ND / ND / 47 / 47
204 / 19.6 / 7.4 / 262 / 0.7 / 0.93 / 1.4 / 2.3 / 0.33 / 196 / ND / ND / 78 / 78
205 / 23.9 / 7.1 / 146 / 0.03 / 0.27 / 0.8 / 1.1 / 0.12 / 124 / ND / ND / 46 / 46
316 / 18.6 / 6.9 / 268 / 0.24 / 0.16 / 1.3 / 1.5 / 0.51 / 200 / ND / ND / 69 / 69
LOR / 0.01 / 0.01 / 0.1 / 0.1 / 0.01 / 5 / 1 / 1 / 1 / 1

LOR, limit of reporting; ND, not detected (< LOR); -, not measured; T, temperature; EC, electrical conductivity; NH3, Ammonia Nitrogen; NO2/3-, Nitrite + Nitrate as N; TKN, Total Kjeldahl Nitrogen as N; TN, Total Nitrogen as N; TP, Total Phosphorus as P; SS, suspended solids; HO-alk, hydroxide alkalinity as CaCO3; CO32-, carbonate alkalinity as CaCO3; HCO3-, bicarbonate alkalinity as CaCO3; Alk, total alkalinity as CaCO3

Table SI 4(continued)

February 2012

Site # / Analyte
T / pH / EC / NH3 / NO2/3- / TKN / TN / TP / SS / HO-alk / CO32- / HCO3- / Alk
(°C) / S/cm) / (mg/L)
34 / 17.1 / 7.0 / 885 / 0.03 / 0.15 / 0.4 / 0.6 / 0.19 / 12 / ND / ND / 101 / 101
202 / 21.1 / 6.8 / 140 / 0.55 / 0.07 / 1.5 / 1.6 / 0.46 / 5 / ND / ND / 58 / 58
204 / 17.7 / 6.9 / 243 / ND / 0.71 / 1.2 / 1.9 / 1.89 / 21 / ND / ND / 103 / 103
205 / 22.2 / 7.1 / 167 / 0.07 / 0.27 / 1.3 / 1.6 / 0.13 / 28 / ND / ND / 51 / 51
316 / 18.5 / 7.3 / 667 / 0.19 / 0.07 / 1.3 / 1.4 / 2.4 / 47 / ND / ND / 97 / 97
LOR / 0.01 / 0.01 / 0.1 / 0.1 / 0.01 / 5 / 1 / 1 / 1 / 1

LOR, limit of reporting; ND, not detected (< LOR); -, not measured; T, temperature; EC, electrical conductivity; NH3, Ammonia Nitrogen; NO2/3-, Nitrite + Nitrate as N; TKN, Total Kjeldahl Nitrogen as N; TN, Total Nitrogen as N; TP, Total Phosphorus as P; SS, suspended solids; HO-alk, hydroxide alkalinity as CaCO3; CO32-, carbonate alkalinity as CaCO3; HCO3-, bicarbonate alkalinity as CaCO3; Alk, total alkalinity as CaCO3

March 2012

Site # / Analyte
T / pH / EC / NH3 / NO2/3- / TKN / TN / TP / SS / HO-alk / CO32- / HCO3- / Alk
(°C) / S/cm) / (mg/L)
34 / 18.8 / 7.2 / 549 / 0.04 / 0.62 / 0.1 / 0.7 / 0.06 / 10 / ND / ND / 119 / 119
202 / 20.9 / 6.8 / 75 / 0.5 / 0.32 / 0.6 / 0.9 / 0.12 / 14 / ND / ND / 39 / 39
204 / 19.6 / 9.9 / 539 / 0.1 / 1.61 / 0.1 / 1.7 / 0.88 / 12 / ND / 20 / 190 / 210
205 / 22.0 / 7.5 / 124 / 0.1 / 0.73 / 0.1 / 0.8 / 0.15 / 96 / ND / ND / 47 / 47
316 / 19.0 / 6.8 / 224 / 0.13 / 0.52 / 0.2 / 0.7 / 0.44 / 41 / ND / ND / 74 / 74
LOR / 0.01 / 0.01 / 0.1 / 0.1 / 0.01 / 5 / 1 / 1 / 1 / 1

LOR, limit of reporting; ND, not detected (< LOR); -, not measured; T, temperature; EC, electrical conductivity; NH3, Ammonia Nitrogen; NO2/3-, Nitrite + Nitrate as N; TKN, Total Kjeldahl Nitrogen as N; TN, Total Nitrogen as N; TP, Total Phosphorus as P; SS, suspended solids; HO-alk, hydroxide alkalinity as CaCO3; CO32-, carbonate alkalinity as CaCO3; HCO3-, bicarbonate alkalinity as CaCO3; Alk, total alkalinity as CaCO3

SI 5Dissolved metals data

Metals: The filtered water samples were sent to a commercial laboratory in Melbourne (ALS Environmental) for analysis of dissolved arsenic (As), barium (Ba), beryllium (Be), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn) by inductively coupled plasma mass spectrometry (ICP-MS). Dissolved mercury (Hg) was determined by a cold vapour flow injection mercury system (CV/FIMS). Nutrient concentrations (Ammonia (NH3 as N), nitrite (NO2-) and nitrate (NO3-) as NOx, Total Kjeldahl Nitrogen (TKN), Total Nitrogen (TN as TKN + NOx) and Total Phosphorus (TP) were determined by Discrete Analyser.

Other parameters screened were suspended solids (SS), hydroxide alkalinity (as CaCO3), Carbonate Alkalinity (as CaCO3), Bicarbonate Alkalinity (as CaCO3) and Total Alkalinity (as CaCO3).

Table SI 5October 2011

Site # / Element
As / Ba / Be / Cd / Co / Cr / Cu / Fe / Hg / Mn / Ni / Pb / V / Zn
(mg/L)
34 / ND / 0.065 / ND / ND / ND / ND / 0.004 / ND / ND / 0.052 / 0.003 / ND / ND / 0.062
202 / 0.004 / 0.024 / ND / ND / ND / ND / 0.002 / 0.18 / ND / 0.028 / 0.001 / 0.002 / ND / ND
204 / ND / 0.024 / ND / ND / 0.001 / ND / 0.012 / 0.07 / ND / 0.027 / 0.004 / 0.001 / ND / 0.12
205 / 0.002 / 0.025 / ND / ND / ND / ND / ND / 0.29 / ND / 0.068 / 0.002 / 0.005 / ND / ND
316 / 0.002 / 0.049 / ND / ND / ND / ND / 0.005 / 0.33 / ND / 0.02 / 0.005 / ND / ND / 0.013
LOR / 0.001 / 0.001 / 0.001 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.05 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.01 / 0.005

LOR, limit of reporting; ND, not detected;

Table SI 5November 2011

Site # / Element
As / Ba / Be / Cd / Co / Cr / Cu / Fe / Hg / Mn / Ni / Pb / V / Zn
(mg/L)
34 / 0.001 / 0.031 / ND / 0.0001 / ND / ND / 0.004 / 0.13 / ND / 0.032 / 0.002 / ND / ND / 0.121
202 / 0.008 / 0.02 / ND / ND / ND / ND / 0.002 / 0.49 / ND / 0.061 / 0.001 / 0.003 / ND / 0.048
204 / 0.002 / 0.034 / ND / 0.0004 / ND / ND / 0.012 / ND / ND / 0.034 / ND / ND / 0.176 / 0.1
205 / 0.002 / 0.024 / ND / ND / ND / ND / 0.001 / 0.24 / ND / 0.041 / 0.002 / ND / ND / 0.009
316 / 0.001 / 0.022 / ND / ND / ND / ND / 0.003 / 0.12 / ND / 0.027 / 0.002 / ND / ND / 0.034
LOR / 0.001 / 0.001 / 0.001 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.05 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.01 / 0.005

LOR, limit of reporting; ND, not detected.

Table SI 5(continued)

December 2011

Site # / Element
As / Ba / Be / Cd / Co / Cr / Cu / Fe / Hg / Mn / Ni / Pb / V / Zn
(mg/L)
34 / 0.001 / 0.052 / ND / ND / ND / 0.002 / 0.007 / 0.75 / ND / 0.038 / 0.006 / ND / 0.01 / 0.073
202 / 0.005 / 0.018 / ND / ND / ND / 0.001 / 0.003 / 0.2 / ND / 0.034 / 0.001 / 0.001 / ND / 0.036
204 / 0.001 / 0.038 / ND / 0.0001 / 0.002 / 0.01 / 0.011 / 0.09 / ND / 0.021 / 0.005 / ND / 0.01 / 0.136
205 / 0.003 / 0.011 / ND / ND / ND / 0.003 / 0.003 / 0.51 / ND / 0.014 / 0.001 / ND / 0.01 / 0.036
316 / ND / 0.041 / ND / ND / ND / ND / 0.004 / 0.1 / ND / 0.048 / 0.004 / ND / 0.01 / 0.023
LOR / <0.001 / <0.001 / <0.001 / <0.0001 / <0.001 / <0.001 / <0.001 / <0.05 / <0.0001 / <0.001 / <0.001 / <0.001 / <0.01 / <0.005

LOR, limit of reporting; ND, not detected.

.

January 2012

Site # / Element
As / Ba / Be / Cd / Co / Cr / Cu / Fe / Hg / Mn / Ni / Pb / V / Zn
(mg/L)
34 / ND / 0.058 / ND / ND / ND / ND / 0.002 / 0.1 / ND / 0.256 / 0.002 / ND / ND / 0.036
202 / 0.006 / 0.027 / ND / 0.0003 / ND / ND / 0.002 / 1.06 / ND / 0.275 / 0.001 / 0.003 / ND / 0.015
204 / ND / 0.023 / ND / ND / ND / ND / 0.009 / 0.08 / ND / 0.125 / 0.002 / 0.005 / ND / 0.156
205 / 0.001 / 0.007 / ND / ND / ND / ND / ND / 0.31 / ND / 0.048 / ND / ND / ND / ND
316 / 0.001 / 0.031 / ND / ND / ND / ND / 0.001 / ND / ND / 0.126 / 0.002 / ND / ND / ND
LOR / 0.001 / 0.001 / 0.001 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.05 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.01 / 0.005

LOR, limit of reporting; ND, not detected.

Table SI 5(continued)

February 2012

Site # / Element
As / Ba / Be / Cd / Co / Cr / Cu / Fe / Hg / Mn / Ni / Pb / V / Zn
(mg/L)
34 / ND / 0.058 / ND / ND / ND / 0.002 / 0.005 / 0.12 / ND / 0.1 / 0.002 / ND / ND / 0.067
202 / 0.01 / 0.037 / ND / ND / ND / 0.002 / 0.002 / 1.1 / ND / 0.113 / 0.002 / 0.007 / ND / 0.017
204 / 0.001 / 0.02 / ND / 0.0004 / 0.005 / 0.002 / 0.015 / 0.16 / ND / 0.041 / 0.005 / 0.002 / ND / 0.179
205 / 0.002 / 0.02 / ND / ND / ND / 0.001 / 0.002 / 0.18 / ND / 0.02 / ND / ND / ND / 0.012
316 / 0.004 / 0.035 / ND / ND / ND / ND / 0.002 / ND / ND / 0.077 / 0.008 / ND / ND / 0.014
LOR / 0.001 / 0.001 / 0.001 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.05 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.01 / 0.005

LOR, limit of reporting; ND, not detected.

March 2012

Site # / Element
As / Ba / Be / Cd / Co / Cr / Cu / Fe / Hg / Mn / Ni / Pb / V / Zn
(mg/L)
34 / ND / 0.06 / ND / ND / ND / ND / 0.006 / 0.11 / ND / 0.024 / 0.004 / ND / ND / 0.039
202 / 0.004 / 0.021 / ND / ND / ND / ND / 0.002 / 0.2 / ND / 0.034 / 0.001 / 0.003 / ND / 0.019
204 / 0.002 / 0.035 / ND / ND / ND / 0.008 / 0.011 / ND / ND / 0.012 / 0.005 / 0.008 / ND / 0.035
205 / 0.003 / 0.008 / ND / ND / ND / ND / 0.002 / 0.28 / ND / ND / 0.001 / ND / ND / 0.013
316 / 0.002 / 0.034 / ND / ND / ND / ND / 0.003 / ND / ND / 0.033 / 0.003 / ND / ND / 0.017
LOR / 0.001 / 0.001 / 0.001 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.05 / 0.0001 / 0.001 / 0.001 / 0.001 / 0.01 / 0.005

LOR, limit of reporting; ND, not detected.

SI6: Risk Assessment methods - herbicides

SI6.1 Risk Quotient (RQ) Method

This method to evaluate the potential risk to aquatic organisms and ecosystems is a deterministic method in which the risk ratio is expressed as measured environmental concentrations (MECs) divided by predicted no-effect concentration (PNEC)or reported no effect concentrations (NOEC), and is calculated using: