Dr. Patricia L. Gillis

Research Scientist - Freshwater Invertebrate Ecotoxicology and Immunotoxicology

Current research and/or projects

Contributing to Environment Canada’s mandate to conduct research on the impacts of contaminants on aquatic ecosystems

  • Investigate the toxicity of waterborne contaminants (metals, chloride, municipal wastewater effluents) to freshwater mussels
  • Assess the role that water quality and waterborne contaminants have in the recovery of endangered freshwater mussels
  • Examine links between immunotoxicity and disease resistance in bivalves
  • Employ various tools to assess the bioavailability of metals to invertebrates (including the biotic ligand model and biomarkers such as metallothioenein)

Professional activities / interests

Co-supervises graduate and undergraduate thesis students (McMaster University)

Member of Graduate Student Advisory Committees (McMaster University and Wilfrid Laurier University)

Member of the Ontario Freshwater Mussel Recovery Team

Member of the Canadian Inter-Governmental Environmental Toxicity Group

Education and awards

Post-doctoral Fellow: University of Guelph and McMaster University

Ph.D.  University of Waterloo, M.Sc. and Hon. B.Sc. University of Guelph

Recipient of Best Student Paper Award in the journal Environmental Toxicology and Chemistry, the Davis Scholarship in Ecology (University of Waterloo), and an Ontario Graduate Scholarship

Key publications

Gillis P.L., 2011. Assessing the toxicity of sodium chloride to the glochidia of freshwater mussels: Implications for salinization of surface waters.  Environmental Pollution. 159:1702-1708.

Gillis P.L., McGeer, J.C., Wilkie W.P., Mackie G.L., Ackerman J.D.   2010.  The effect of natural dissolved organic carbon on the sensitivity of larval freshwater mussels (glochidia) to acute copper exposure.  Environmental Toxicology and Chemistry 29:2519–2528.

Gillis, P.L., R.J. Mitchell, A.N. Schwalb, K.A. McNichols, G.L. Mackie, C.M. Wood and J.D. Ackerman.  2008. Sensitivity of the glochidia of freshwater mussels to copper: assessing the effect of water hardness and dissolved organic carbon on the sensitivity of endangered species.  Aquatic Toxicology. 88:137-145.

Gillis P.L. and C.M. Wood. 2008.  Investigating a potential mechanism of Cd resistance in Chironomus riparius larvae using kinetic analysis of calcium and cadmium uptake.  Aquatic Toxicology 89: 180–187.

Béchard K.M., Gillis P.L., Wood C.M. 2008.  Trophic transfer of Cd from larval chironomids (Chironomus riparius) exposed via sediment or waterborne routes, to zebrafish (Danio rerio): tissue-specific and subcellular comparisons.  Aquatic Toxicology 90:310–321.

Gillis, P.L., P. Chow-Fraser, J.F. Ranville, P.E. Ross and C.M. Wood. 2005. Daphnia need to be gut cleared too: the effect of exposure to and ingestion of metal-contaminated sediment on whole-body metal concentrations and the gut clearance patterns in D. magna. Aquatic Toxicology 71: 143-154.

Gillis, P.L., D.G. Dixon, U. Borgmann and T.B. Reynoldson. 2004. Uptake and depuration of cadmium, nickel, and lead in laboratory exposed Tubifex tubifex and corresponding changes in the concentration of a metallothionein-like protein. Environmental Toxicology and Chemistry 23: 76-85.

Gillis, P.L., L.C. Diener, T.B. Reynoldson and D.G. Dixon. 2002. Cadmium induced production of a metallothionein-like protein in Tubifex tubifex (Oligochaeta) and Chironomus riparius (Diptera): correlation with whole body (reproduction and growth) endpoints of toxicity. Environmental Toxicology and Chemistry 21: 1836-1844.

Gillis, P.L. and G.L. Mackie. 1994. Impact of the zebra mussel, Dreissena polymorpha, on populations of Unionidae in Lake St. Clair. Canadian Journal of Zoology 72: 1260-1271.

Research facility

867 Lakeshore Rd.
Burlington, ON L7S 1A1


Adjunct Associate Professor, Department of Biology, McMaster University

Faculty of Graduate Studies, Wilfrid Laurier University

Member, Society of Environmental Toxicology and Chemistry (1995-present)