Use of Phytoremediation to Mitigate Mercury Pollution Caused by Artisanal Gold Mining

1. Use of Phytoremediation to Mitigate Mercury Pollution Caused by Artisanal Gold Mining Daren Many & Natalie Gordon BZ 572

2. The World’s Worst Pollution Problems – The Top Ten of the Toxic Twenty (2008) • Indoor Air Pollution • Urban Air Quality • Untreated Sewage • Groundwater Contamination • Contaminated Surface Water • Artisanal Gold Mining • Industrial Mining Activities • Metals smelting and processing • Radioactive Waste and Uranium Mining • Used Lead Acid Battery Recycling Source: BlacksmithInstitute.org

3. Artisanal Mining Process– Mercury Amalgamation Amalgamation Separation Decomposition Gold Melting Photo credit: David Cleary

4. Potential for Mercury Pollution Amalgamation Spillage Separation Residual Hg Discharge Decomposition Release of vapors Gold Melting Release of vapors

5. What is Mercury (Hg) Three forms: • Elemental mercury (Hg(0)) – liquid or vapor form • Ionic Salts – mercurous (I) or mercuric (II) states • Organometallic compound - methylmercury

6. Why is Hg Dangerous? Elemental Hg converted to Methyl Mercury through oxidation and methylation.

7. Artisanal Mining Pollution Biggest challenge with small-scale mining: Mercury in the atmosphere and Mercury poisoning Entire families can inhale the gaseous mercury Skin rash caused by handling inorganic mercury Photo credit: Blacksmith Institute

8. Map of World Gold Mining Activities – Artisanal Mining

9. Current Mercury Pollution Remediation Practices Worldwide there are no real mercury pollution cleanups occurring due to a lack of funding and/or interest.

10. Phytoremediation of Mercury

11. Phytovolatization Arabidopsis thaliana Nicotiana tabacum Liriodendron tulipifera

12. Phytovolatization Mercury transformed into less toxic form Genetic Engineering Volatized mercury will eventually be recycled

13. Phytominingfor Gold Studies being done to phytomine gold and extract Hg simultaneously using Canola. Adjuvants used to increase gold solubility and uptake

14. Phytomining Offsets expense of remediation Returns land to agriculture Adjuvants may mobilize elements into groundwater

15. Will phytoremediation actually work?

16. Responses to Point Source Mercury Contamination Hinton et al., 2001

17. What’s The Best Solution? A hybrid approach: Phytoremediation to volatilize mercury already in soil/water Introduction of cleaner gold mining methods, including use of retorts Education of miners on the proper use and handling of mercury and on better extraction options

18. Citations: Anderson, Chris, Meech, John A.. (2002). Growing Gold: Using Metal Accumulating Plants to Produce Gold. Available: http://www.mining.ubc.ca/cerm3/growing%20metals.html. Blacksmith Institute. http://www.blacksmithinstitute.org/artisanal-gold-mining.html Blue, Lisa Y., Van Aelstyn, Mike A., Matlock, Matthew and Atwood, David A. 2008. Low-level mercury removal from groundwater using a synthetic chelating ligand. Water Research 42(8- 9):2025-2028. Davila, J. 2009. Mercury reduction by bacteria isolated from informal mining zones. Advanced Materials Research 71-73():637-640. Ebbs, Stephen D., Kolev, Spas D., Piccinin, Robert C.R., Woodrow, Ian E., Baker, Alan J.M.. (2010). Solubilization of heavy metals from gold ore by adjuvants used during gold phytomining. Minerals Engineering. 23 , p. 819-822. Elena Rodrigueza; Jason G. Parsonsb; Jose R. Peralta-Videab; Gustavo Cruz-Jimenezc; Jaime Romero-Gonzalezc; Blanca E. Sanchez-Salcidob; Geoffrey B. Saupeb; Maria Duarte-Gardead; Jorge L. Gardea-Torres. (2007). Potential of ChilopsisLinearis for Gold Phytomining: Using Xas to Determine Gold Reduction and Nanoparticle Formation Within Plant Tissues . International Journal of Phytoremediation. 9 (2), p.133-147. Henry, Jeanna R.. (2000). An Overview of the Phytoremediation of Lead and Mercury. National Network of Environmental Management Studies, p. 1-55. Jadia, Chhotu D., Fulekar, M.H. 2008. Phytoremediation of heavy metals: Recent techniques. African Journal of Biotechnology 8(6):921-928.

19. Citations cont’d: Lone,MohammadIqbal, He, Zhen-li, Stoffella, Peter J., Yang, Xiao-e. (2008). Phytoremediation of heavy metal polluted soils and water: Progresses and perspectives. Journal of Zhejiang University. 9 (3), p. 210-220. Moreno, Fabio N., Anderson, Christopher W.N., Stewart, Robert B., Robinson, Brett H. 2007. Phytofiltration of mercury-contaminated water: volatilzation and plant-accumulation aspects. Environmental and Experimental Biology 62:78-85. Mulligan, C.N., Yong, R.N. and Gibbs, B.F. 2001. Remediation technologies for metal-contaminated soils and groundwater: an evaluation. Engineering Geology 60(1-4):193-207. Padmavathiamma, P. 2007. Phytoremediation technology: hyper-accumulation metals in plants. Water, Air and Soil Pollution 184(1-4):105-126. Renault, S., Szczerski, C., Sailerova, E., Fedikow, M.A.F.. (2004). Phytoremediation and revegetation of mine tailings and bio-ore production: progress report on plant growth in amended tailings and metal accumulation in seedlings planted at Central Manitoba minesite.. Report of Activities. 1 (1), p257-261. Rugh, C., Meagher, R.B.. (2003). Phytoremediation Technologies. Available: http://rydberg.biology.colostate.edu/Phytoremediation/2003/Amy/phytoremediationtechnologies.html. Speigel, S. 2010. International guidelines on mercury management in small-scale gold mining. Journal of Cleaner Production 18(4):375-385. Veiga, Marcello M. and Hinton, Jennifer J. 2002. Abandoned artisanal gold mines in the Brazilian Amazon: a legacy of mercurypollution. Natural Resources Forum 26:15-26.