Widespread atmospheric Tellurium contamination in industrial and remote regions of Canada

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1 Supporting Information For Widespread atmospheric Tellurium contamination in industrial and remote regions of Canada Authors: Johan A. Wiklund 1*, Jane L. Kirk 1*, Derek C.G. Muir 1, Jacques Carrier 2, Amber Gleason 1, Fan Yang 1, Marlene Evans 3, Jonathan Keating 3. 1 Aquatic Contaminants Research Division, Environment Canada, Burlington, ON Canada, L7R 4A6 2 National Laboratory of Environmental Testing, Environment Canada, Burlington, ON Canada, L7R 4A6 3 Aquatic Contaminants Research Division, Environment Canada, Saskatoon, SK Canada, S7N 3H5 *Corresponding Authors: jane.kirk@canada.ca, johan.wiklund@canada.ca Description of Supporting Information Number of pages: 13 Number of tables: 4 Number of figures: 6 References S1

2 SI Methods Sediment core dating Measurement of 21 Pb activity and subsequent dating of sediment cores was carried as previously described for sediment records from the ELA ON and Flin Flon MB 1, or for Plastic Lake ON 2. The additional cores were similarly dated at the Canada Centre for Inland Waters, Burlington using alpha and/or gamma ray spectrometry. Separate determinations of 226 Ra activity (which is equal to the quantity of supported 21 Pb activity) were performed on all cores. The excess or unsupported 21 Pb which is supplied from atmospheric fallout 3-5 was calculated as: 21 Pb ex = 21 Pb total - 21 Pb supported and the distribution of the 21 Pb ex inventory with respect to the cumulative dry sediment mass was used for sediment age model calculations. The Constant Rate of Supply (CRS) age model was used to calculate 21 Pb-based ages and sedimentation rates 3-5. The reference accumulation rate approach was utilized (see Eq ) ensuring a complete integration of the unsupported 21 Pb inventory. For cores analyzed via gamma ray spectrometry, 137 Cs activity profiles were also used to help validate the 21 Pb age model. As 137 Cs is an artificial radionuclide produced from the fission of heavy isotopes (U and Pu), the period of peak 137 Cs activity in the sediment record was expected to correspond to 1963, the period of peak nuclear weapons fallout in North America 4. Extrapolation of sediment ages below the horizon applicable to 21 Pb dating was done assuming an equivalent dry mass accumulation rate occurred below the 21 Pb datable portion of the sediment record as seen within the 21 Pb datable portion of the record. Resulting 21 Pb, 226 Ra and 137 Cs activity profiles and age depth model results are shown in SI Fig. 1. S2

3 Greenland (Denmark) Alaska (USA) Yukon North West Territories Central Alberta (Rural) British Columbia USA Northern Alberta (Oil sands mining & upgrading) Alberta Estevan Saskatchewan (Coal Mining & Combustion) Nunavut Thompson Manitoba (Ni Smelter) Manitoba Saskatchewan Ontario Flin Flon Manitoba (Cu/Zn Smelter) ELA (Remote natural area) KP SB Quebec Dorset / Plastic L. (Remote natural area) USA Kejimkujik Nova Scotia (Remote natural area) KP (Former Cu) and SB (Current Cu/Ni) Major Mining andsmelting Figure S1. Locations of lake sediment cores collected across Canada and discussed for Tellurium concentration profiles and deposition history. Also note is the presence of major industrial activity or classification of rural or remote natural areas in the absence of local significant point sources of emissions to air. While lake sediment cores were not analyzed from near Sudbury ON (SB) or Keweenaw Peninsula (KP) MI USA for Te, it is expected they were/are some of the larger Te emissions sources in the Laurentian Great Lakes region, although others (smelters + coal plants) exist. Map modified from Natural Resources Canada 21, Atlas of Canada ( S3

4 a) Battle Activity (Bq g -1 ) b) Pigeon Activity (Bq g -1 ) c) AirPort Pond Activity (Bq g -1 ) Depth (cm) Depth (cm) Ra Activity 21 Pb Activity d) TM-1A Activity (Bq g -1 ) CRS dates Extrapolated dates e) TM-3A Activity (Bq g -1 ) f) TM-4A Activity (Bq g -1 ) Depth (cm) Depth (cm) g) TM-9A Activity (Bq g -1 ) h) Peskowest Activity (Bq g -1 ) i) Cobrielle Activity (Bq g -1 ) Depth (cm) Ra Activity 21 Pb Activity 137 Cs Activity CRS dates Extrapolated dates Cs peak Depth (cm) Figure S2. Sediment core 21 Pb, 137 Cs and 226 Ra activity profiles and CRS age model results for sediment records from a-b) rural central Alberta, c) Estevan Saskatchewan, d-g) Thompson Manitoba and h-i) Kejimkujik Nova Scotia shown in Fig. 1 and S1, and not previously published elsewhere 1,2. S4

5 Figure S3 Cumulative inventory of anthropogenic Te for Flin Flon area lakes (Douglas, Nekik and Loucks) vs distance from the smelter with the lake specific inventory weighted by wind source direction 1. From this relation, we estimated that 72.2 t (metric ton) of anthropogenic sourced Te was deposited within 5 km of the smelter between For comparison, within an equivalent area, 8.2 t of anthropogenic sourced has Te been deposited near the ELA (186-21). S5

6 Figure S4 Mean (± 95% C.I.) anthropogenic Tellurium deposition at the Experimental Lakes Area (ELA ON) reconstructed from five lake sediment cores as presented in Fig. 3, accompanied by similarly calculated anthropogenic Te fluxes from other regions where pre-industrial sediment data MDL exists (pre-18 for Cobrielle (NS) and Plastic Lake (ON), and pre-19 for Pigeon (AB)) or as described below (Thompson T1 and Airport Pond). The Plastic Lake (Dorset ON) record greatly resembles the ELA ON record until after the completion of the 38 m Sudbury smelter super stack (2 nd tallest in the world) after which Te deposition increases greatly. At Thompson MB, anthropogenic Te deposition was initially low in lake T1 but increased sharply after the start of mining (1959) and Ni refining (1961) in Thompson 6 (M-STEM-#573). Pre-19, (n=8) data was used for Thompson T1A core pre-anthropogenic baseline even though the determined values (mean =.1 ±.5 (1 SD) mg kg -1 ) was below the MDL (.2 mg kg -1 ). While individually these 8 data points are below nominal MDL, the aggregate and relatively consistent result of these 8 data points justifies their use in describing the local natural baseline. For Airport Pond SK, all pre-191 sediment samples were below the MDL (.2 mg kg -1 ), thus, for this lake we chose a more conservative approach using the pre-coal mining (n=2) Te (MDL value) / Al mass ratio to infer the pre-coal mining (pre-188s) and coal power plant (pre-191) baseline, and thus the flux values must be considered tentative. As Te concentrations in the Airport Pond record are all low, the high flux values for this site are driven primarily by the high sedimentation rates of this site. Not shown here are the anthropogenic Te fluxes from lakes near Flin Flon, where the maximum observed fluxes at Douglas, Nekik and Loucks lakes were 11, 3, and 25 µg Te m -2 yr -1 respectively, located 5, 43 and 75 km from the Flin Flon Cu smelter. S6

7 Figure S5 Plastic Lake (Dorset ON) sediment core metal concentrations increase greatly after the 197s, likely reflecting enhanced long-range dispersion of emissions from Sudbury after the INCO superstack (38 m) in Sudbury began operation in Sudbury which is a major Cu, Ni, Ag, Pd, Rh, and Te producer. Note that Rh was below method detection limit of.2 mg kg -1 prior to 195. S7

8 Figure S6 Lake sediment inventories of A) total and B) anthropogenic Te in relation to relative drainage area (CA/LA = lake terrestrial catchment area / lake area). As reported previously 7, high order lakes show a departure due to many upstream, lower order lakes receiving, storing, processing, and exporting some portion of atmospheric contributions to the downstream higher order receiving lake (i.e. ELA 377). Further investigation (Fig. 4) thus concentrates only on the low order ELA lakes. Linear regression ±95% C.I. shown. S8

9 Table S1 Coring locations, depth, total unsupported 21 Pb inventory, focusing factor (FF) terms and, downwind direction and distance from local significant point sources. Depth 21 Pb ex Direction from and km Lake Latitude N Longitude W (m) (Bq cm -2 ) FF to local point source Rural Alberta Region, Battle S 38 Pigeon S 42 Northern Alberta, Oil Sands Region SW SW 26 NE NE Y6A W 112 RAMP SE 88 Estevan, Saskatchewan Area Airport Pond S Thompson, Manitoba Area 1A E A ENE A SW A W 48.6 Flin Flon, Manitoba Area Douglas SW 5. Nekik NE 43.7 Loucks E 75. ELA, Ontario Area NA NA NA NA NA Dorset, Ontario* Plastic Lake NA Kejimkujik National Park, Nova Scotia Cobrielle NA Peskowesk NA a Genesse Coal Generating station (Coal; 1286 MW). b Distance to AR6 (~center of Oil Sands production region 8 ). c Boundary Dam Generating Station (Coal; 672 MW) and Shand Generating Station (Coal; 276 MW). d Thompson Manitoba Nickel smelter. e Flin Flon Manitoba Copper/Zinc smelter. * 225km from Sudbury Cu/Ni smelter, 16 km from the Greater Toronto Area) NA = Not Applicable. a b c d e S9

10 Table S2. ELA lake catchment, hydrologic properties and sediment Te inventories. Lake LA CA Water Areal** Anthropogenic Te Lake Catchment Max Mean Lake Lake Lake* renewal Discharge Total Te Area Area Depth depth Volume Order Discharge time (τ) qs Inventory Inventory Retention ha ha m m m 3 m 3 yr -1 yr m yr -1 mg m -2 mg m -2 R*** LAKE LAKE LAKE LAKE LAKE *Lake Input or Output assumes steady state and is calculated using lake and catchment areas using assumed annual precipitation, evapotranspiration and evaporation values 9 Water renewal time = water volume / total discharge **Areal Discharge = Annual discharge / lake area Post-186 inventory. ***R assumes maximum anthropogenic Te post-186 input = 1.53 ±.24 mg m -2 S1

11 Table S3. Method detection limits (MDL*), % recovery and % precision of elemental analysis of Standard Reference Materials (SRMs ) determined via ICPMS after hot-block aqua regia digest of sediment. NRC MESS-3 NIST RM 874 LKSD-3 Mean Element MDL* Recovery Precision Recovery Precision Recovery Precision precision (mg kg -1 ) (%)** (%)*** (%)** (%)*** (%)** (%)*** (%) Ag Al As B Ba Be Bi Ca Ce Cd Co Cr Cs Cu Fe Ga Ge K La Li Mg Mn Mo Na Nb Ni P Pb Pd Pt Rb Rh S Sb Sc Se Sn Sr Te Ti Tl U V W Y Zn Zr ** % recovery of certified value of SRM (certified value not available for all elements). *** Mean precision of multiple QA runs of SRMs. S11

12 Table S4. Methods comparison between Standard Operational Procedures (SOPs) for total recoverable metals by: A) microwave digestion and B) hot-block digestion of a range of SRMs (NRC-MESS-3 (B), NRC-MESS-2 (A), NIST-874 (A,B), LKSD-3 (A,B), PACS (A), WQB1 (A), WQB3 (A), TH2 (A), HR1 (A), SUD1 (A), BCSS (A) ). Superscript denotes SRMs analyzed by each method. SOP # A) Total Recoverable Micro-Wave B) = Total Recoverable Hot Block % Recovery % Recovery Ag 19.4 Al As Au.1 B 16.8 Ba Be Ca Cd Ce 58.5 Co Cr Cs 34.3 Cu Fe K La 81. Li Mg Mn Mo Na Nb 19.5 Ni P 92. Pb Rb 3.4 S 12.1 Sb Sc 33.5 Se Sn 13.4 Sr Ti Tl 13.3 U V Y 59.2 Zn Note Te data is not available for SRMS, though experiments with blanks, spikes and possible interferences find the data free of bias (see Methods). S12

13 SI References 1. Wiklund, J. A., Kirk, J. L., Muir, D. C. G., Evans, M., Fan, F., Keating J. and Parsons, M. T. Anthropogenic mercury deposition in Flin Flon Manitoba and the Experimental Lakes Area Ontario (Canada): A multi-lake sediment core reconstruction. Sci. Total Environ. 217, 586, Muir, D. C. G., Wang, X., Fan, F., Nguyen, N., Jackson, T. A., Evans, M. S., Douglas, M., Köck, G., Lamoureux, S., Pientz, R., Smol, J. P. Vincent, W. F. and Dastoor, A. A. Spatial trends and historical deposition of mercury in Eastern and Northern Canada inferred from lake sediment cores. Environ. Sci. Technol. 29, 43, Robbins, J. A. Geochemical and geophysical applications of radioactive lead isotopes. In Biochemistry of Lead; Nriagu, J. O., Ed.; Elsevier: Amsterdam, 1978; pp Appleby, P. G. Chronostratigraphic techniques in recent sediments. In: Tracking environmental change using lake sediments: Basin analysis, coring, and chronological techniques; Last, W. M.; Smol, J. P., Eds.; Kluwer Academic Publishers: Dordrecht 21; pp Sanchez-Cabeza, J. A.; Ruiz-Fernández, A. C. 21 Pb sediment radiochronology: An integrated formulation and classification of dating models. Geochim. Cosmochim. Ac. 212, 82, M-STEM (Manitoba Science, Technology, Energy and Mines. Mineral Inventory File #573, Thompson Mine, Blais, J. M. and Kalff, J. Atmospheric loading of Zn, Cu, Ni, Cr, and Pb to lake sediments: The role of catchment, lake morphometry, and physico-chemical properties of the elements. Biogeochemistry 1993, 23, Kelly, E. N. Schindler, D. W., Hodson, P. V., Short, J. W., Radmanovich, R. and Nielsen, C. C. Oil sands development contributes elements toxic at low concentrations to the Athabasca River and its tributaries. PNAS, 21, 17 (37), Curtis, P. J. and Schindler, D. W. Hydrologic control of dissolved organic matter in low-order Precambrian shield lakes Biogeochemistry 1997, 36, S13

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