EN-Virtual Seminar

The Environmental Division (EN) of Chemical Institute Canada brings together members in the field of environmental sciences and engineering. Together with the Environmental Chemistry program in the Department of Chemistry at the University of Toronto, we are pleased to introduce a new series of virtual talks covering a wide range of topics in environmental chemistry, including in the atmospheric, terrestrial, freshwater, marine and Arctic environments.
We are particularly thrilled to showcase new and exciting work by early career researchers in the division. Whether you want to learn about the latest developments in environmental science and engineering, or stay connected with the broader community in these fields, join us in this series.
We look forward to “seeing” you!
How to join:
- Once you have registered for the symposium series, you will receive a unique link to access the webinar. Please do not distribute this link.
- Registration will be confirmed for upcoming sessions between September 22, 2020 to July 7, 2021. Should the series be extended you will be notified by email.
Upcoming Events & Speakers
Wednesday, January 13, 2021, 4:00 PM ET
Host by Cora Young, York University

Atmospheric Chemistry and Water - From Cloudwater Chemistry to Household Humidifiers
Ran Zhao
University of Alberta
Atmospheric Chemistry and Water - From Cloudwater Chemistry to Household Humidifiers
Speaker: Ran Zhao, Assistant Professor, Department of Chemistry, University of Alberta
Abstract:
According to the World Health Organization (WHO), air pollution is responsible for 7 million deaths worldwide. Air pollutants are present both outdoor and indoors. The indoor air quality is more important than ever during the pandemic, as people are forced to stay home for a prolonged period. Atmospheric chemistry plays a vital role in the formation, evolution, and fate of air pollutants. Fundamental laboratory experiments have been an essential aspect of atmospheric research to provide kinetic and mechanistic information. The theme of this talk is related to the role of water in the outdoor and indoor air. The aqueous-phase is the largest condensed phase in the context of atmospheric chemistry, and water plays a convoluted role in the reactivity and partitioning of air pollutants. In this talk, I will be giving an overview of two projects conducted by my research group. The first project is the investigation of the pH-dependence of cloudwater photochemistry. The interplay between acid-base chemistry and photochemistry is a unique yet unexplored aspect of aqueous-phase atmospheric chemistry. In the second project, the potential contributions of ultrasonic humidifiers to indoor air pollutants are discussed. Household humidifiers are commonly employed to combat dry indoor air, which is particularly relevant to cold and dry Canadian Winter. Our study shows that ultrasonic humidifiers are giving rise to very high concentrations of particulate matter in a household. Emissions from humidifiers may induce previously unrecognized chemical processes in the indoor environment.
Wednesday, January 27, 2021, 4:00 PM ET
Polycyclic aromatic compounds in Canada: Translating environmental chemistry for changemakers
Elisabeth Galarneau Environment and Climate Change Canada
Wednesday, February 10, 2021 4:00 PM ET
TBD
Samar Moussa Environment and Climate Change Canada
February 24, 2021 04:00 PM ET
TBD
Melissa McKinney McGill University
Additional Dates:
- March 10, 2021 04:00 PM ET
- March 24, 2021 04:00 PM ET
- April 7, 2021 04:00 PM ET
- April 21, 2021 04:00 PM ET
- May 5, 2021 04:00 PM ET
- May 19, 2021 04:00 PM ET
- June 9, 2021 04:00 PM ET
- June 16, 2021 04:00 PM ET
- July 7, 2021 04:00 PM ET
Past Events
Wednesday, December 16,2020, 4:00 PM ET

Permafrost and Hydrological change as drivers of Arctic freshwater biogeochemistry
Melissa Lafreniere Queen's University
Permafrost and Hydrological change as drivers of Arctic freshwater biogeochemistry
Speaker: Melissa Lafreniere, Queen's University (@permafrostDOC)
Abstract:
Changing climate has direct effects on both the land, through permafrost thaw, and on the hydrologic cycle, via the amount and timing of seasonal inputs of snow and rainfall. Deeper thaw and degradation of permafrost alters surface and subsurface hydraulic properties, which can allow water to infiltrate and circulate more deeply, pool in new depressions, and flow through new pathways on altered surface topography. These changes in permafrost and hydrology are leading to changes in the mobilization and transport of carbon, nutrients, and metal contaminants within surface waters. There is a great need to better understand the mobilization, and especially the fate, of permafrost derived materials, as these are altering aquatic ecosystems and water quality in culturally important waterways, and have the potential to feedback on the atmospheric CO2 budget and therefore global climate change.
Research at the Cape Bounty Arctic Watershed Observatory in the Canadian High Arctic has been examining climate driven permafrost and hydrological changes and their impacts on surface water biogeochemistry for more than fifteen years. This seminar will review studies from Cape Bounty and other High Arctic sites that illustrate how changes in permafrost hydrology are driving changes in the nature of dissolved organic matter and nutrient fluxes, the relative importance of dissolved vs particulate fluxes, and the total fluxes of mercury in these watersheds.
This body of research highlights that improving our ability to project and model the biogeochemical response of permafrost watersheds to future warming, and the fate of permafrost derived carbon, nutrients and contaminant fluxes requires a better understanding of the spatial variability of the permafrost characteristics. Specifically, we need to be able to identify and model the permafrost characteristics that 1) determine the source and likely nature of the material reservoirs (i.e. how does the composition and distribution of organic matter, nutrients and contaminants vary in permafrost); and those characteristics that 2) dictate the potential for hydrological connectivity with these material reservoirs to be established (e.g. the abundance and distribution of ice in the upper permafrost, and the intensity and seasonality of surface water inputs).
Wednesday, November 18, 2020, 4:00 PM ET

Analysis of Drinking Water Disinfection Byproducts: from Individual Compounds to Complex Mixtures
Xing-Fang Li
University of Alberta
Analysis of Drinking Water Disinfection Byproducts: from Individual Compounds to Complex Mixtures
Speaker: Xing-Fang Li, Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta
Abstract:
Drinking water disinfection is the most effective means for preventing waterborne diseases. However, the very disinfection processes that kill microorganisms also produce a variety of disinfection by-products (DBPs) from reactions between the disinfectants (e.g., chlorine) and the natural organic matter in water. Epidemiological studies have consistently shown an increased risk of bladder cancer associated with consumption of chlorinated drinking water. Analytical limitations prevented these earlier studies from measuring or identifying the actual DBPs in drinking water. Thus, the exact DBPs in the disinfected water that contribute to the increased bladder cancer risk are unclear. To date, we know approximately 700 DBPs; however, the majority of DBPs produced in disinfected water remain unidentified. Faced with tremendous challenges and knowledge gaps, regulatory agencies can only regulate a few DBPs that are easy to measure. To find the real culprit(s) from the unknowns, we have focused on the development of ultra-sensitive analytical techniques to discover new DBPs of health importance. These techniques take advantage of specific pre-concentration, efficient chromatographic separation, and highly sensitive mass spectrometry detection. Our current development of analytical technologies aims at the discovery of highly toxic individual DBPs (e.g. nitrosamines and haloquinones) and comprehensive characterization of all DBPs in disinfected drinking water and their precursors in source water.
Wednesday, October 21, 4:00 PM ET

Biological nitrogen fixation: Trace metals matter!
Jean-Philippe Bellenger
Université de Sherbrooke
Biological nitrogen fixation: Trace metals matter
Speaker: Dr. Jean-Philippe Bellenger, Université de Sherbrooke
Abstract: Nitrogen is, with phosphorus, the primary limiting nutrient on earth. Biological nitrogen fixation (BNF) is an important source of new reactive N in unmanaged ecosystems; contributes up to 50% of new N in high-latitude ecosystems. Factors controlling BNF thus critically affect ecosystems function and their response to global climate change. The role of environmental factors such as atmospheric N deposition, temperature, humidity, on BNF is well known and have been the subject of countless studies. Here, I will summarize findings that revealed that trace metal availability also plays a critical role.
Three isoforms of the enzyme nitrogenase have been described; the canonical molybdenum (Mo) nitrogenase which requires Mo in its active site and two alternative nitrogenases, the vanadium and iron-only nitrogenases. For almost a century, BNF has been considered to primarily rely on the Mo-based isoform. Over the last 20 years we revealed that (i) the low bioavailability of Mo on land limits BNF in many ecosystems from the tropical forest to the arctic tundra, (ii) alternative nitrogenase are more common than previously believed, (iii) the use of alternative nitrogenases to cope with Mo limitation is widespread, and (iv) alternative nitrogenases contribute up to 50% of BNF in boreal ecosystems.
These results reveal a strong link between the biogeochemical cycle of macro- and micronutrients in terrestrial ecosystems, question the reliability of current BNF estimates, which have likely been largely underestimated in many ecosystems and call for additional consideration of alternative nitrogenases in experimental and modelling studies of terrestrial biogeochemistry.
Wednesday, September 23, 4:00 PM ET
Cryospheric chemistry across the ocean-sea ice-atmosphere interface
Feiyue (Fei) Wang
University of Manitoba
Cryospheric chemistry across the ocean-sea ice-atmosphere interface
Speaker: Dr. Feiyue (Fei) Wang
Centre for Earth Observation Science, University of Manitoba, Winnipeg, Canada; feiyue.wang@umanitoba.ca
Abstract: Cryo-reactions (chemical reactions at freezing temperatures) are well known to play a major role in atmospheric chemistry. Evidence is mounting that the Earth’s surface cryosphere is also a much more chemically and biogeochemically active environment than previously thought. This presentation will provide a synopsis of cryo-reactions in the Arctic marine cryosphere, highlighting their role in the cycling of CO2, mercury, and oil spills across the ocean-sea ice-atmosphere interface in a changing climate. New research initiatives and collaborative opportunities at the Sea-ice Environmental Research Facility and Churchill Marine Observatory will also be discussed.
Dr. Fei Wang is Professor and Canada Research Chair (Tier 1) in Arctic Environmental Chemistry at the University of Manitoba. He directs the Ultra-Clean Trace Elements Laboratory (UCTEL), leads the Sea-ice Environmental Research Facility (SERF), and is Chief Scientist of the Ocean-and-Sea-Ice Mesocosm (OSIM) of the Churchill Marine Observatory (CMO).
Take your place in Canada’s thriving chemical science, engineering, and technology community. Join Now
Contact the Organizer
Dr. Jennifer G. Murphy
Department of Chemistry
University of Toronto
sites.chem.utoronto.ca/murphygroup/
jen.murphy@utoronto.ca