Dr. Alexandra (Sandy) Steffen

Image Alexandra Steffen
Atmospheric Mercury Specialist

Lead mercury researcher for Atmospheric Processes Research Section specializing in environmental processes relating to the transport, transformation and deposition of mercury in and around the atmosphere.

Current research and/or projects

Lead mercury researcher for Atmospheric Processes Research (ARQP) Section specializing in environmental processes relating to the transport, transformation and deposition of mercury in and around the atmosphere.

  • Specialize in designing research to study the processes driving the transformation of mercury in and around the Canadian and Arctic atmospheres
  • Investigate spatial and temporal trends of atmospheric mercury on a national, regional and global scale
  • Atmospheric monitoring of mercury using passive and active sampling methods
  • Science advisor to the Canadian government for national policy including the Minamata Convention on Mercury
  • Unit lead for the ARQP Data Management Team

Professional activities / interests

  • Principle investigator for atmospheric mercury research for the Northern Contaminants Program (NCP), Crown-Indigenous Relations and Northern Affairs Canada (CIRNAC)  
  • Designated expert for Canada for the ad-hoc Mercury Experts Group for the Minamata Convention and the Arctic Monitoring and assessment Programme
  • Editor and lead for the Canadian Mercury Science Assessment
  • Canadian designate for the GEO-GOS4M Flagship program
  • Member of the United Nations Environmental Program Fate and Transport Partnership Program
  • Expert Scientific Witness for the Teck-Frontier environmental impact assessment hearing for the Government of Canada panel (October 2018)
  • Scientific Steering Committee Member for the International Conference on Mercury as a Global Pollutant (ICMGP) 2009-present
  • Guest Editor Elementa Atmospheric Science Domain

Education and awards

PhD Natural Sciences, Leuphana University Lüneberg, 2013

M.Sc. Environmental Analytical Chemistry, University of Waterloo, 1996

B.Sc. Hons. Chemistry, minor Environmental Studies, University of Waterloo, 1993

Awards:

  • Women in Science SciTech Award – Science and Technology Branch: Award for excellence in science leadership (2020)
  • Citation of Excellence - Environment and Climate Change Canada: Award for Exceptional Quality of work as part of the Tech Frontier Panel Review Team: (2019)
  • Instant Award – Environmental Protection Branch: Award for Excellent work on behalf of the government of Canada for work during the negotiations for the Intergovernmental Negotiating Committee for the Minamata Convention on Mercury (2016)

International experience and/or work

  • International expert on atmospheric mercury science for the Minamata Convention ad-hoc Mercury Expert Group to design
  • Member of the United Nations Environmental Program Fate and Transport Partnership Program
  • Scientific Steering Committee Member for the International Conference on Mercury as a Global Pollutant (ICMGP) 2009-present
  • Scientific input to the Arctic Monitoring and Assessment Program Mercury Assessments and the UNEP/AMAP Global Mercury Assessment
  • Initiated a Global Mercury Passive Sampling Project to address gaps in atmospheric mercury data around the world
  • Canadian delegate for the Asia Pacific Mercury Monitoring Network (APMMN)
  • Canadian designate for the GEO-GOS4M Flagship program
  • Participated and/or led international Arctic field research studies on mercury

Key publications

Published over 55 peer reviewed publications and have over 6300 science citations on peer reviewed publications. Google scholar h-index 39, i10-index 56.

Steffen, A. (editor) Steffen A., Morrison H., Kos G., Li Y.-F., Neimi D., O'Driscoll N., Pannu R., Siciliano S. D., Cole A., St Louis V. L., Graydon J. A., Mitchell C. P. J., Oswald C., Lehnherr I., Chetelat J., Lucotte M., Dastoor A., Durnford D., Harris R., Burgess N., Gamberg M., Depew D., Evans M., Scheuhammer A. M., Basu N., Curren M., Donaldson S., Gibson J., Leech T., Lye E. 2016. Canadian Mercury Science Assessment - Report. Gatineau, Canada: Environment and Climate Change Canada, 793 pp.

Steffen, A. (editor) Steffen A., Morrison H., Kos G., O'Driscoll N., Arp P., St Louis V. L., Chetelat J., Dastoor A., Burgess N., Gamberg M., Scheuhammer A. M., Leech T. 2016. Canadian Mercury Science Assessment - Summary of Key results. Gatineau, Canada: Environment and Climate Change Canada, 39 pp.

Global evaluation and calibration of a passive air sampler for gaseous mercury (2018). McLagan D. S., Mitchell C. P. J., Steffen A., Hung H., Shin C., Stupple G., Olson M. L., Luke W. T., Kelley P., Howard D., Edwards G. C., Nelson P. F., Xiao. H., Sheu G.-R., Dreyer A., Huang H., Hussain B. A., Lei Y. D., Tavshunsky H., Wania F. ACP,18: 5905-5919.

Atmospheric mercury speciation and mercury in snow over time at Alert, Canada (2014). Steffen, A., Bottenheim, J., Cole, A., Ebinghaus, R., Lawson, G. and Leaitch, W.R. ACP, 14: 2219-2231.

Convective forcing of mercury and ozone in the Arctic boundary layer induced by leads in sea ice (2014). Moore, C.W., Obrist, D., Steffen, A., Staebler, R., Douglas, T.A., Richter, A. and Nghiem, S.V. Nature. doi: 10.1038/nature12924

A comparison of data quality control protocols for atmospheric mercury speciation measurements (2012). Steffen, A., Scherz, T., Olson, M.L., Gay, D.A. and Blanchard, P. JEM, 14: 752-765. (cover feature)

Gas-particle partitioning of atmospheric Hg(II) and its effect on global mercury deposition. (2012) Amos, H.M., Jacob, D.J., Holmes, C.D., Fisher, J.D., Wang, Q., Corbitt, E.S., Galarneau, E., Rutter, A.P., Gustin, M.S., Steffen, A., Graydon, J.A., St. Louis, V., Talbot, R.W., Edgerton, E.S., Zhang, Y. and Sunderland, E.M.  ACP, 12: 591-603. (203 citations)

A synthesis of atmospheric mercury depletion event chemistry in the atmosphere and snow (2008). Steffen, A., Douglas, T., Amyot, M., Ariya, P., Aspmo, K., Berg, T., Bottenheim, J., Brooks, S., Cobbett, F., Dastoor, A., Dommergue, A., Ebinghaus, R., Ferrari, C., Gardfeldt, K., Goodsite, M.E., Lean, D., Poulain, A., Scherz, C., Skov, H., Sommar, J. and Temme, C. ACP, 8: 1445-1482. (289 citations)

Arctic springtime depletion of mercury. (1998) Schroeder, W.H., Anlauf, K.G., Barrie, L.A., Lu, J.Y., Steffen, A. and Schneeberger, D.R. Nature, 394:331-332. (549 citations)

Research facility

4905 Dufferin Street
Toronto, ON M3H 5T4
Canada

Affiliations

Adjunct Professor at the University of Toronto Scarborough, Department of Physical and Environmental Science, Toronto, Canada (2019-2022)

Language

English
French