The group has done a lot of research in Canada and around the world to examine processes leading to the formation and degradation of methylmercury, especially in wetlands. Methylmercury is produced by microbes, largely in anoxic environments and is important because it is the primary form of mercury that accumulates in organisms and through diet, in humans. Research approaches are varied and include a mixture of fieldwork, laboratory experimentation and modelling.
For an idea of this kind of work, below are a few selected papers published by our group about methylmercury in wetlands:
Tang, W.; Bai, X.; Zhou, Y.; Sonne, C.; Wu, M.; Shiung Lam, S.; Hintelmann, H.; Mitchell, C.P.J.; Johs, A.; Gu, B.; Nunes, L.; Liu, C.; Feng, N.; Yang, Y.; Rinklebe, J.; Lin, Y.; Chen, L.; Zhang, Y.; Wang, J.; Li, S.; Wu, Q.; Sik Ok, Y.; Xu, D.; Li, H.; Zhang, X.; Ren, H.; Jiang, G.; Chai, Z.; Gao, Y.; Zhao, J.; Zhong, H. (2024) A hidden demethylation pathway removes mercury from rice plants and mitigates mercury flux to food chains. Nature Food, 5, 72-82.
Zhong, H.; Zhou, H.; Li, Y.; Li, C.; Tsui, M.T.-K.; Mitchell, C.P.J.; Zhou, Y.; Yang, Y.; Chen, L.; Ren, H.; Tang, W. (2024) Methylmercury photodegradation in paddy water: An overlooked process mitigating mercury risks. Water Research, 253, 121332.
McCarter, C.P.R.; Sebestyen, S.D.; Coleman Wasik, J.K.; Engstrom, D.R.; Kolka, R.K.; Jeremiason, J.D.; Swain, E.B.; Monson, B.A.; Branfireun, B.A.; Balogh, S.J.; Nater, E.A.; Eggert, S.L.; Ning, P.; Mitchell, C.P.J. (2022) Long-term experimental manipulation of atmospheric sulfate deposition to a peatland: response of methylmercury and related solute export in streamwater. Environmental Science & Technology, 56(24), 17615-17625.
Haynes, K.H.; Kane, E.; Potvin, L.; Lilleskov, E.; Kolka, R.K.; Mitchell, C.P.J. (2017) Mobility and transport of mercury and methylmercury in peat as a function of changes in water table regime and plant community. Global Biogeochemical Cycles, 31, 233-244.
Strickman, R.J.; Mitchell, C.P.J. (2017) Methylmercury production and accumulation in urban stormwater ponds and habitat wetlands. Environmental Pollution, 221, 326-334.
Johnson, N.; Mitchell, C.P.J.; Engstrom, D.R.; Bailey, L.; Coleman Wasik, J.K.; Berndt, M.E. (2016) Methylmercury production in a chronically sulfate-impacted sub-boreal wetland. Environmental Science: Process and Impacts, 18, 725-734.
Hoggarth, C.G.J.; Hall, B.D.; Mitchell, C.P.J. (2015) Mercury methylation in high and low-sulphate impacted wetland ponds within the Prairie Pothole Region of North America. Environmental Pollution, 205, 269-277.
Mitchell, C.P.J. and Gilmour, C.C. (2008) Methylmercury production in a Chesapeake Bay salt marsh. Journal of Geophysical Research – Biogeosciences, 113, G00C04.
Mitchell, C.P.J., Branfireun, B.A. and Kolka, R.K. (2008) Spatial characteristics of net methylmercury production hot spots in peatlands. Environmental Science & Technology, 42(4): 1010-1016.
