Supporting Information. Tracking the global distribution of Persistent Organic Pollutants accounting for e-waste exports to developing regions.

Transcription

1 Supporting Information for Tracking the global distribution of Persistent Organic Pollutants accounting for e-waste exports to developing regions. Knut Breivik 1,2, *, James M. Armitage 3,*, Frank Wania 3, Andrew J. Sweetman 4 and Kevin C. Jones 4 1 Norwegian Institute for Air Research, Box 100, NO-2027 Kjeller, Norway 2 Department of Chemistry, University of Oslo, Box 1033, NO-0315 Oslo, Norway 3 Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, Canada M1C 1A4 4 Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK Corresponding authors and addresses: Knut Breivik, Norwegian Institute for Air Research, Box 100, NO-2027 Kjeller, Norway, kbr@nilu.no, Phone: , Fax: James M. Armitage, Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, Canada M1C 1A4, james.armitage@utoronto.ca, Phone: , Fax: Total 8 pages: Additional information, Tables S1-S3, and Figures S1-S4. S1

2 Brief account of the global PCB emission mass balance model The global historical production of 22 selected PCB congeners was estimated on the basis of available data on the production of total PCBs and/or production of individual technical mixtures (e.g. Aroclors) as well as their congener compositions. 1, 2 Most PCBs were produced in the major industrial regions at that time, i.e. close to half of the historical production occurred in the USA with the reminder mostly in Europe (including Russia) and in Japan. 2 In a next step, the global historical usage pattern of PCBs was estimated for 114 individual countries and years (1930 until 1993) on the basis of data on national and regional PCB consumption and trade. As reliable data mainly existed for the top consuming countries, surrogate data (GDPs) were used to complement national consumption patterns. 1, 2 These estimates were in turn utilized as input to a dynamic global PCB emission mass balance model, 2, 3 which links production and formulation, consumption and consecutive stages of the chemical life-cycle with atmospheric emissions. In an attempt to quantify key uncertainties in the resulting estimates, three different emission scenarios (low, default, high) were presented. 1-3 Independent evaluations exploring these scenarios in the context of mass balance studies or as input to various environmental fate models 2 have suggested that the higher emission scenarios are likely to be the more accurate 4-13 and the higher emission scenario is therefore the only scenario further explored here. This also facilitates increased transparency as other input parameters, variable across the three original emissions scenarios (e.g., production rates of individual congeners), are kept constant, allowing us to focus on the potential implications of the export of wastes for emissions of PCBs alone which is comparable and consistent with past emission estimates. S2

3 Figure S1. The BETR Global model ( with zones identified by number. Selected zones discussed explicitly in the main manuscript are highlighted. These include both importing regions (e.g. West Africa [132, 133] and China [92, 116]) and exporting regions (Central Europe [61], US [79] and Japan [94]). Zone 93 includes parts of both China and Japan, in addition to North and South Korea. S3

4 Table S1. Examples of emissions via passive volatilization calculated by model zone, RIUOC and scenario, normalized to the Zone 61 MGEN scenario. See the main text for explanation of the derivation of these emission estimates. See Table S2 for physical-chemical properties of the four RIUOCs. Zone 61 MGEN MNET RIUOC-1 (PCB 28) RIUOC-2 (PCB 153) RIUOC-3 (BDE 47) RIUOC-4 (BDE 209) Zone 79 MGEN MNET Zone 116 MGEN MNET Zone 133 MGEN MNET S4

5 Table S2. Physical-chemical property values for the RIUOCs. Property RIUOC 1 (PCB 28) RIUOC 2 (PCB 153) RIUOC 3 (BDE 47) MW (g/mol) RIUOC 4 (BDE 209) Partitioning log KAW log KOW log KOA Temp-dep (J/mol) ΔUOA (-ΔUA)* ΔUOW Degradation t1/2 Air (h)** Vegetation (h) Freshwater (h) Ocean water (h) Soil (h) Sediment (h) Temp-dep of t1/2 (J/mol) ΔEA air ΔEA vegetation ΔEA freshwater ΔEA ocean water ΔEA soil ΔEA sediment * Assuming ΔUOA = ΔUO - ΔUA, assuming ΔUO = 0 ** Global average degradation half-life in air is adjusted by the model to account for spatial and temporal variability in OH radical concentrations. S5

6 Table S3. Physical-chemical property values for five additional PCBs (at 25 o C). 4, Property PCB 28 PCB 101 PCB 118 PCB 138 PCB 180 MW (g/mol) Partitioning log K AW log K OW log K OA Temp-dep (J/mol) ΔU OA ΔU OW Degradation t 1/2 Air (h)* Vegetation (h) Freshwater (h) Ocean water (h) Soil (h) Sediment (h) Temp-dep of t 1/2 (J/mol) ΔE A air ΔE A vegetation ΔE A freshwater ΔE A ocean water ΔE A soil ΔE A sediment * Global average degradation half-life in air is adjusted by the model to account for spatial and temporal variability in OH radical concentrations. S6

7 Figure S2. Aggregated emission estimates for PCB 153 in t/yr for different emission scenarios over the period Figure S3. Map of the globe displaying the higher global emission scenario for 7PCBs in 2005 with 1 x 1 resolution (in Kg year -1 grid cell -1 ). Figure S4. Modeled concentrations of i) PCB 28 and ii) PCB 153 in the atmospheric boundary layer of Zone 116 (China) under the three emission scenarios. S7

8 Literature Cited in the Supporting Information 1. Breivik, K.; Sweetman, A.; Pacyna, J. M.; Jones, K. C., Towards a global historical emission inventory for selected PCB congeners - a mass balance approach 1 Global production and consumption. Science of the Total Environment 2002, 290, (1-3), Breivik, K.; Sweetman, A.; Pacyna, J. M.; Jones, K. C., Towards a global historical emission inventory for selected PCB congeners - A mass balance approach 3 An update. Science of the Total Environment 2007, 377, (2-3), Breivik, K.; Sweetman, A.; Pacyna, J. M.; Jones, K. C., Towards a global historical emission inventory for selected PCB congeners - a mass balance approach 2 Emissions. Science of the Total Environment 2002, 290, (1-3), Wania, F.; Daly, G. L., Estimating the contribution of degradation in air and deposition to the deep sea to the global loss of PCBs. Atmospheric Environment 2002, 36, (36-37), Wania, F.; Su, Y. S., Quantifying the global fractionation of polychlorinated biphenyls. Ambio 2004, 33, (3), Malanichev, A.; Mantseva, E.; Shatalov, V.; Strukov, B.; Vulykh, N., Numerical evaluation of the PCBs transport over the Northern Hemisphere. Environ. Pollut. 2004, 128, (1-2), Macleod, M.; Riley, W. J.; McKone, T. E., Assessing the influence of climate variability on atmospheric concentrations of polychlorinated biphenyls using a global-scale mass balance model (BETR-global). Environ. Sci. Technol. 2005, 39, (17), Eckhardt, S.; Breivik, K.; Li, Y. F.; Manø, S.; Stohl, A., Source regions of some persistent organic pollutants measured in the atmosphere at Birkenes, Norway. Atmospheric Chemistry and Physics 2009, 9, (17), Hauck, M.; Huijbregts, M. A. J.; Hollander, A.; Hendriks, A. J.; van de Meent, D., Modeled and monitored variation in space and time of PCB-153 concentrations in air, sediment, soil and aquatic biota on a European scale. Science of The Total Environment 2010, 408, (18), Breivik, K.; Czub, G.; McLachlan, M. S.; Wania, F., Towards an understanding of the link between environmental emissions and human body burdens of PCBs using CoZMoMAN. Environ. Int. 2010, 36, Gong, S. L.; Huang, P.; Zhao, T. L.; Sahsuvar, L.; Barrie, L. A.; Kaminski, J. W.; Li, Y. F.; Niu, T., GEM/POPs: a global 3-D dynamic model for semi-volatile persistent organic pollutants - Part 1: Model description and evaluations of air concentrations. Atmospheric Chemistry and Physics 2007, 7, (15), Stemmler, I.; Lammel, G., Long-term trends of continental-scale PCB patterns studied using a global atmosphere-ocean general circulation model. Environmental Science and Pollution Research 2012, 19, (6), Lammel, G.; Stemmler, I., Fractionation and current time trends of PCB congeners: evolvement of distributions studied using a global atmosphere-ocean general circulation model. Atmospheric Chemistry and Physics 2012, 12, (15), Anderson, P. N.; Hites, R. A., OH radical reactions: The major removal pathway for polychlorinated biphenyls from the atmosphere. Environ. Sci. Technol. 1996, 30, (5), Schenker, U.; MacLeod, M.; Scheringer, M.; Hungerbuhler, K., Improving data quality for environmental fate models: A least-squares adjustment procedure for harmonizing physicochemical properties of organic compounds. Environ. Sci. Technol. 2005, 39, (21), Mackay, D., Multimedia Environmental Models: The Fugacity Approach. 2 ed.; CRC Press, Boca Raton, FL: 2001; p 272. S8