Two Toronto schools found to have high
readings for electromagnetic fields will be
undergoing further testing to ensure
students and staff aren't at risk, a Toronto
Public Health official says.
In what's believed to be a first in the
city, Toronto Public Health tested 31
schools this spring that are next to hydro
The tests found that two – Monsignor John
Corrigan elementary in Etobicoke, and JS
Woodsworth senior public school in
Scarborough – had the highest readings.
The Etobicoke Catholic school had a
snapshot reading of 69.9 milligauss (mG) and
the one in Scarborough showed 29 mG.
According to public health, background
levels of electromagnetic fields (EMF) in
urban areas are usually less than 1 mG.
Both tests were done outside, on school
property. Further testing is scheduled for
A test at Tamarisk Park, near the
Etobicoke school, had readings of between 33
and 81 mG.
Canada follows international
guidelines permitting short-term exposure at
no more than 833 mG, studies have shown the
risk of leukemia in children increases if
they're exposed to average levels,
year-round, above 3 or 4 mG.
Ronald Macfarlane, a supervisor in the
city's environmental health assessment
section, said short-term exposure to high
EMF levels won't significantly raise a
person's yearly average level. There's no
need for parents to be alarmed, he said.
"We're encouraging schools to take
practical measures to not unduly increase
exposure to EMF," Macfarlane said.
Still, public health is recommending the
schools come up with a "management plan" so
children at the two schools aren't exposed
too long to areas with high readings,
The Catholic board will notify parents in
The public board will wait for the
results from indoor testing, and if concerns
remain after those results are in, a meeting
will be scheduled with parents.
Electric and magnetic fields are
invisible lines of force, part of the
spectrum of electromagnetic radiation.
Aside from studying EMF levels beside
hydro corridors, public health has published
an extensive new report on EMF exposure in
general. In it, Dr. David McKeown, the
city's medical officer of health, calls for
housing developments, schools and
recreational facilities beside these
corridors to develop "management plans."
The goal is to
minimize yearly average
exposure, especially for children. Plans can
be as simple as locating areas of high child
activity away from EMF hot spots.