Chemicals Released into Our Air & Water that can Pose Risks to Our Health & the Health of Our Environment

Speaker: Heather MarshallWritten by: Esha & Sheena Jain



Toronto is an ever growing city, with some areas more exposed to carcinogens than others, as high rise buildings are being built near industrial areas. It is evident that many companies are not reporting toxic chemicals, which even in the smallest amounts can be harmful. As a result community member of Toronto have pushed “the rights to know bylaw” in order to gain more information regarding the toxins being used and released into the environment. The Toronto public health map website now discloses the top 25 toxic substances used as they are now required to share it with the public. Of the list of 25 toxic substances, Cadmium, Tetrachloroethylene, Polycyclic Aromatic Hydrocarbons are all cancer causing toxins.

Tetrachloroethylene also known as “Perc” is of particular interest as it is used quite a bit. It is important to know that Perc causes respiratory, nervous and reproductive system issues. It adds to air pollution and has a negative effect on aquatic environments, soil and groundwater contamination.  

Perc is used in dry cleaning and many still continue to use it despite the negative impact it has on public health. Dry cleaning is a misnomer as the clothing is actually soaked in the chemical solvent, then dried and pressed with specialized machinery. There is no such thing as “organic washing,”either,  therefore be aware of false advertising of such signs.  

With the assistance of the Toronto Environmental Alliance a scorecard was created to see what other chemical toxins are being used. This has allowed the public to compare the scores with other cleaners to see what they use, allowing them to choose a dry cleaner that they feel fit. Note that wet cleaning does not negatively impact one’s health or the environment. It is better on clothing and not linked to cancer, air or water pollution and there are no lingering chemical odors.

The Toronto Environmental Alliance has been successful and were able to pass a bylaw known as DineSafe or BodySafe, which is posted in the window of approved dry cleaners allowing the public to know it has been tested, scored and is risk free.

For more information regarding Toronto public health maps go to:

Discussion questions:

  1.       How does Tetrachloroethylene effect the environment (air, aquatics, soil) and what are the outcomes from the toxin exposure?

Air: When dry cleaners use Perc, it is released directly into the air. Perc can be transported long distances in the air as it breaks down slowly.

Perc can move into the air through vapors ending up in homes and apartments above dry cleaning shops.

Aquatics: The dry cleaning industry also produces liquid waste that contains Perc, which may end up at waste treatment facilities. Perc evaporates from water into the air, but some may remain in the water. It is slow to break down in water as well.

Soil: Perc may contaminate the soil when the waste leaks out from the waste treatment facilities. It can evaporate from the soil or end up into the ground water. It also breaks down slowly in the soil.

  1.      Are there any precautions that we as a population can take to reduce the amount of chemicals/toxins exposure?
  • The amount of exposure from Perc vapor intrusion into homes/apartments above dry cleaning facilities can be minimized by ensuring the area is well ventilated. This can be achieved  by increasing the air exchange rate between indoor and outdoor air.
  • If you are concerned that you live near a waste site or near contaminated groundwater or soil, be sure to prevent your children from playing in or ingesting the dirt.
  • Be sure to read product labels carefully and store products in outdoor sheds to reduce indoor air exposure.
  1.    What medical tests can be done to determine Perc exposure?

Perc can be measured in the breath and its breakdown products can be measured in the blood and urine. Detection does not predict the health effects that may develop from the exposure. Tests need to be done within days after exposure as the breakdown products of Perc leave the body rapidly.

  1.       What are the long term effects that Perc will have on the health of those exposed?

Long term exposure may cause neurological effects, including headaches, alteration in mood, memory, attention, reaction time, cognitive functioning or vision changes.

Higher exposure may damage the liver, kidney, immune system, have hematologic effects and impair reproductive development.

Pregnant mothers may face miscarriages, birth defects and slowed growth of fetus in utero after oral and inhalation exposure.

Long periods of exposure may lead to high risk of bladder cancer, multiple myeloma or non-hodgkin’s lymphoma; however, there is limited evidence for these specific cancers.  

Based on evidence, Perc is indeed considered to be carcinogenic by all routes of exposure. According to studies, rats and mice were exposed to Perc for 2 years via inhalation and stomach tube. The results demonstrated a development of  mononuclear cell leukemia in rats and hepatocellular carcinoma in mice.


ATSDR - Public Health Statement: Tetrachloroethylene (PERC). Atsdrcdcgov. 2016. Available at: June 3, 2016.


Tetrachloroethylene (Perchloroethylene) | Technology Transfer Network Air Toxics Web site | US EPA. www3epagov. 2016. Available at: Accessed June 3, 2016