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Meet the team


Karl Jobst

Principal investigator (

Karl Jobst is an associate professor in the Department of Chemistry at Memorial University. His research interests focus on analytical and environmental chemistry. He teaches general chemistry (Chem 1050) and analytical method development (Chem 4156/6156).


Mahsa Aghaei

Mahsa obtained her M.Sc. at Isfahan University of Technology where she conducted research on polycyclic aromatic hydrocarbons in wastewater. Currently, she is interested in developing a method to characterize micro-/nanoplastics in water and air. 


Justine Bissonnette

Justine Bissonnette obtained her B.Sc. at the University of Waterloo, where she was introduced to ion mobility and mass spectrometry. Currently, she is developing a state-of-the-art method to detect micro-/nanoplastics in human blood using ion mobility-mass spectrometry.

Meera Bissram completed her undergraduate degree at the University of Toronto. She is interested in using advanced mass spectrometry techniques to characterize known and unknown environmental contaminants. Her hobbies include spending time at the beach and listening to soca music.


Emmanuel Tolefe

Emmanuel Tolefe studied Chemistry at Augustine University Ilara, where he conducted research on heavy metal contamination of soils. He is currently working on a novel three dimensional separation technique (GCxGCxIMS) that will aid in characterizing complex environmental mixtures.


Chloe Penney

Chloe Penney is a MUN alumnus whose undergraduate research focused on non-targeted screening of perfluoroalkyl substances in cosmetics and human plasma. Her current project focuses on plastics additives in biological samples.


Nikita Harvey

Nikita Harvey is a MUN alumnus with extensive experience on micro-/nanoplastics exposure experiments led by Dr. Cahill. Currently, she is quantifying plastics exposure in humans by characterizing placental tissue in a project co-supervised by Dr. Jobst.


Mikela Rowsell

Mikela Rowsell is a Chemistry undergraduate researcher who is interested in studying residential exposure to micro-/nanoplastics in indoor air. Currently, she is focused on expanding her methodology to capture more polymers and polymer additives in environmental and biological media.


Holly Burden

Holly Burden is currently an undergraduate researcher at MUN. She is interested in studying environmental pollutants using non-targeted mass spectrometry, and her project focuses on the identification of perfluoroalkyl substances in food packaging. 


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Xiaolei Li

Xiaolei Li obtained her B.Eng. from Ocean University of China. Since joining MUN, she has completed an M.Sc. degree focused on modelling the environmental fate of contaminants. Her research led to the development of a new way to find unknown contaminants, such as PFAS (perfluoroalkyl substances).


Roshanak Amiri

Roshanak Amiri obtained her B.Sc. from Shahid Beheshti University.  She is interested in using analytical and computational tools to identify environmental pollutants. She also loves hiking, reading and adventures in nature! She used computational chemistry and mass spectrometry experiments to understand an ion-molecule reaction that can distinguish toxic from non-toxic isomers.


Tannia Chevez

Tannia Chevez is enrolled in the Computational Chemistry program. She is keenly interested in solving challenging chemical and environmental problems using advanced computational methods and technology. She also loves nature and the stars. She used computational chemistry to help identify persistent organic pollutants in a highly complex mixture of (mixed) halogenated n-alkanes.

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Sarah Tiessen

Sarah Tiessen completed her undergraduate degree in Biochemistry at Memorial University. She is extremely interested in contributing to the overall health of our environment through examining bioaccumulation of chemical pollutants and what can be done to reduce them.


Jake Breen

Jake Breen is completing a Bachelor of Science with plans to do a joint honours in chemistry and applied mathematics.  He is interested in the forensic sciences and is currently working on an environmental "forensics" project to identify fingerprints of air pollution released from industry.  In his free time, Jake enjoys cooking and hiking.


Olivia Critch-Doran

Olivia Critch-Doran is a Physics major who is helping to develop new technology to identify small molecule pollutants in nanoplastics using collision-cross section measurements. She is interested in learning about Mass Spectrometry and she thinks it's neat how ions are affected by external electric and magnetic fields :). She likes knitting and reading in her free time.

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