Researchers in chemistry at the University of Toronto have found in
the ambient air collected in Toronto pollution particles from
Quebec and even the Sahara thanks to the use of laser technology.
Greg Evans, Professor, Department of Chemical Engineering and Applied Chemistry
from the University of Toronto, and his team, have gathered thanks to their
device for the ambient air circulating in College Street along
the university. They found there pollutants from a forest fire that occurred
in Quebec, and, more surprisingly, particles from a storm of
sand in the Sahara. This is real detective work: having
learned of the existence of this fire in Quebec, researchers were able to
identify the particles, originating from the event. Likewise they could
retrace the periple of Saharan dust, crossing the Atlantic
to Mexico then up north to Toronto.
The equipment used for this research integrates a mass spectrometer
laser ablation. The device collects ambient air and particles
prisoners are accelerated. Two lasers with sensors detect them
as they shoot at the speed of a bullet. Once the speed
calculated, a third higher power laser is triggered for
spray the particle. The fragments describe an aerial tube. The
The lightest molecules take less time to cross this tube. They
are analyzed by the chemists and deliver the chemical signature of the
pollutant particle studied.
Greg Evans is now working on the development of a library
grouping the different signatures of potential pollutants. He will be
then now possible thanks to this process to directly identify the type
pollutant in the ambient air without knowing the source.
contacts:
- Greg Evans, Department of Chemical Engineering and Applied Chemistry - tel
: (+1) 416 978 1821 - Email: evansg@chem-eng.utoronto.ca
Sources: University of Toronto website, News @ UofT section, Article
“Globetrotting pollutants turn up on Toronto streets” publishes l19 / 10/2004,
Author: Nicolle Wahl, link:
http://www.news.utoronto.ca/bin6/041019-574.asp
Editor: Renaud Didelot TORONTO,
att-scientifique@consulfrance-toronto.org