Dr Louis Joseph Albert Tremblay

PhD University of Guelph

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Senior Lecturer

Research | Current

I am an ecotoxicologist with interests in the development of methodologies to characterise the effects of anthropogenic stressors on the receiving environment. A multitude of chemicals are developed and used for various roles in daily household, industrial, and agricultural activities. Following their use, these chemicals can enter the environment from a range of sources such as municipal sewage treatment plants and agricultural and urban storm water runoffs and potentially affect the health of exposed biota. The challenge is to characterise and manage the potential risks of these chemicals, and combinations of chemicals, to our unique ecosystems while maximising the intended positive outcomes of their use. My research involves assessment of the toxicity of contaminants and complex mixtures like sewage effluent using biological methodologies underpinned by analytical chemistry.


Special Interests

  • Characterisation the effects of micro-contaminants of their mechanisms of toxicity in key New Zealand species using methodologies based on different levels of biological organisation, from molecular to whole animal.
  • Development of bioindicators and biomarkers in New Zealand native species from different taxa.
  • Use a research approach based on the integration of the quadruple bottom line (environmental, economic, social and cultural) to develop acceptable environmental management options.
  • Risk characterisation and assessment of endocrine disrupting chemicals (EDCs) and remerging contaminants such as pharmaceuticals and personal care products (PPCPs).
  • Risk assessment of multiple stressors and complex mixtures.

Postgraduate supervision

Current post-graduate projects

  • Trace Organic Contaminants in Treated Wastewater discharges: Fate and assessment of risk to the receiving Environments in New Zealand - Jason Mark Strong, PhD, Chemistry Department of Waikato University.
  • Investigation of endocrine disruption in Australian aquatic environments - Philip Scott, PhD, Griffith University, Australia.
  • Toxicity assessment of marine dinoflagellates using echinoid fertilisation and fish embryo toxicity (FET) bioassays -Phoebe Argyle, MSc: Co-supervisors: Mary Sewell, Tim Harwood (Chemistry/Cawthron Institute), Lesley Rhodes (Cawthron Institute).
  • Use of biomarkers in fish bioindicators species to assess the effects of pollution on New Zealand estuaries. Diana Montenegro: Co-supervisor: Gavin Lear. PhD fellowship from Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT).


Past post-graduate projects

  • Evaluation of the ecological impacts of pollution on New Zealand estuaries using a New Zealand marine copepod - Tristan Stringer, PhD, School of Biological Sciences, Canterbury University. Graduated 2013.
  • Characterisation of the effects of multiple stressors using a larval sea urchin toxicity test. Maria Fernanda Hurtado-Roa, MSc. Co-supervisor Kevin Simon (SEnv). MSc fellowship from Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT). Graduated  December 2013.
  • Evaluation of an advanced tertiary sewage treatment plant to remove endocrine active chemicals -Lisa Hamilton, PhD, University of Technology, Sydney, Australia. Graduated 2011.
  • Occurrence of Estrogens in Dairy Effluent and their Fate in the Environment - Jennifer Gadd, PhD, University of Canterbury. Graduated 2009.
  • The ecotoxicology of endocrine disrupting chemicals in Sydney Olympic Park - Christopher Rawson, PhD, University of Technology, Sydney, Australia. Graduated 2009.
  • Development of bioindicators using meiofauna species to evaluate and monitor the health of estuarine environments - Lisa Hack, PhD, Lincoln University. Graduated 2008.
  • Fate and effects of endocrine disruptors from sewage effluent in coastal estuarine environments -Benjamin Tan, PhD, Griffith University, Australia. Graduated 2007.
  • Herbicides and their lethal and sub-lethal effects on the chemical communication system of Xenopus laevis- Kirsty Yuill Proctor, MSc, University of Canterbury. Graduated 2005.
  • Analysing for xenoestrogens in the common cockle (Austrovenus stutchburyi) to determine the risk for human consumption - Nicola Turner, MSc, Lincoln University. Graduated 2004.
  • Estrogenic and androgenic potential of municipal sewage in Australia and New Zealand - Fred Leusch, PhD, Lincoln University. Graduated 2004.
  • Marae-based restoration and management of Oruarangi Creek - Jaroz Adams, MSc. University of Auckland. Graduated 2003.

Areas of expertise

Ecotoxicologist
Ecology, Evolution and Behaviour

Selected publications and creative works (Research Outputs)

  • Tremblay, L. A., Champeau, O., Cahill, P. L., Pullan, S., Grainger, N., & Duggan, I. C. (2018). Assessment of chemical and physical treatments to selectively kill non-indigenous freshwater zooplankton species. New Zealand Journal of Marine and Freshwater Research, 1-16. 10.1080/00288330.2018.1485712
  • Cavanagh, J.-A. E., Trought, K., Mitchell, C., Northcott, G., & Tremblay, L. A. (2018). Assessment of endocrine disruption and oxidative potential of bisphenol-A, triclosan, nonylphenol, diethylhexyl phthalate, galaxolide, and carbamazepine, common contaminants of municipal biosolids. Toxicology in vitro : an international journal published in association with BIBRA, 48, 342-349. 10.1016/j.tiv.2018.02.003
  • Scott, P. D., Coleman, H. M., Khan, S., Lim, R., McDonald, J. A., Mondon, J., ... Warne, M. S. J. (2018). Histopathology, vitellogenin and chemical body burden in mosquitofish (Gambusia holbrooki) sampled from six river sites receiving a gradient of stressors. The Science of the total environment, 616-617, 1638-1648. 10.1016/j.scitotenv.2017.10.148
  • Laroche, O., Wood, S. A., Tremblay, L. A., Ellis, J. I., Lear, G., & Pochon, X. (2018). A cross-taxa study using environmental DNA/RNA metabarcoding to measure biological impacts of offshore oil and gas drilling and production operations. Marine pollution bulletin, 127, 97-107. 10.1016/j.marpolbul.2017.11.042
    Other University of Auckland co-authors: Gavin Lear, Xavier Pochon
  • Tremblay, L. A., Gadd, J. B., & Northcott, G. L. (2018). Steroid estrogens and estrogenic activity are ubiquitous in dairy farm watersheds regardless of effluent management practices. Agriculture, Ecosystems and Environment, 253, 48-54. 10.1016/j.agee.2017.10.012
  • Hawes, N. A., Tremblay, L. A., Pochon, X., Dunphy, B., Fidler, A. E., & Smith, K. F. (2018). Effects of temperature and salinity stress on DNA methylation in a highly invasive marine invertebrate, the colonial ascidian Didemnum vexillum. PeerJ, 610.7717/peerj.5003
    Other University of Auckland co-authors: Xavier Pochon
  • Charry, M. P., Keesing, V., Costello, M., & Tremblay, L. A. (2018). Assessment of the ecotoxicity of urban estuarine sediment using benthic and pelagic copepod bioassays. PeerJ, 610.7717/peerj.4936
    Other University of Auckland co-authors: Mark Costello
  • Tremblay, L. A., Clark, D., Sinner, J., & Ellis, J. I. (2017). Integration of community structure data reveals observable effects below sediment guideline thresholds in a large estuary. Environmental Science: Processes and Impacts, 19 (9), 1134-1141. 10.1039/c7em00073a

Contact details

Alternative contact

Phone: +64 03 539 3290
Email: louis.tremblay@cawthron.org.nz