Environmental Pollutants


The cancer effects of radiation such as X-rays and ultra-violet (UV) radiation are well known. Less certain are the potential health effects of low levels of electromagnetic fields from power lines or radio frequencies from the use of cell phones.

What is radiation?

Radiation is energy that travels as waves or particles through space. People come in contact with radiation in both their living and work environments.

Visit Health Canada: Environmental Radiation for more information on radiation.

Update November 2013: Prudent Avoidance Policy

Board of Health Decision (Nov. 4, 2013)

This report responds to a motion by the Board of Health (BOH) to review the City of Toronto's Prudent Avoidance (PA) policy related to radiofrequencies (RFs) emitted from cell phone towers and to provide an update on evidence regarding public health impacts from exposure to cell tower RFs. 

Industry Canada letter to MOH on RFs in Toronto

Industry Canada completed an original study in 2002 which confirmed that all of the measured sites in the City of Toronto were substantially less than the reconmended limits specified in Health Canada’s Safety Code 6 guidelines.

Radiation and Health


Cell Phone and Wifi

Radiofrequencies (RFs) are all around us. They are produced by telecommunication devices, like radio and television broadcasting, cell phones, cell phone towers, and Wi-Fi. Some devices that you may not think of as a telecommunication device, like water meters, smart meters, baby monitors and wireless routers also emit RFs.


Power Lines and Electromagnetic Fields

Extremely low frequencies (ELFs) are a type of electric and magnetic fields (EMFs) that occur where electricity is generated, transmitted or distributed in power lines or cables, or used in electrical devices such as appliances.



Radon is a colourless, odourless gas that is widely present in the earth's surface. It comes from the radioactive breakdown of uranium. Uranium occurs naturally and can be found in small amounts in the soil, water and air.

Tritium and Public Health

The documents below represent Toronto Public Health's position on Tritium in water.

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