Order Your Supply of Potassium Iodide (KI) Pills

The Canadian Nuclear Safety Commission (CNSC) — the federal agency that monitors the safe operation of nuclear stations — now requires that all homes and businesses within 10 km of a nuclear power station receive a supply of potassium iodide (KI) pills. The City of Toronto, the Region of Durham and Ontario Power Generation are providing you with access to their project website. To order potassium iodide (KI) pills for your home or business, please complete the form at https://preparetobesafe.ca/order Depending on your postal code, order pills even beyond 10 km zone.

The distribution of KI pills

Order your supply of potassium iodide (KI) pills

(the chemical name for potassium iodide) is a salt of stable (not radioactive) iodine. It is an essential nutrient needed in small quantities for the thyroid gland to function properly. KI comes in tablet form and can be easily  swallowed. The effectiveness of KI as a specific blocker of thyroid radioiodine uptake is well established. When taken in the recommended dose and at the right time, KI is effective in reducing the risk of thyroid cancer in individuals or populations at risk of inhalation or ingestion of radioiodines. KI fills up the thyroid with non-radioactive iodine and prevents the uptake of the radioactive molecules. KI does not protect against other types of radiation.

In the event of an emergency that results in a release of radiation to the public, the Chief Medical Officer of Health for Ontario will provide instructions through radio, TV, Internet and other available channels on where, when, how, and by whom KI should be taken. It is important to wait for this notification. Do not take the pills unless instructed to do so. You would only need to take the pills for a short period of time, likely 1 – 2 days. 

Pregnant or breastfeeding women       2 tablets (1 single dose only)
Adults 18+ 2 tablets every 24 hours
Children 3 – 18 1 tablet every 24 hours
Children 1 month – 3 years ½ tablet daily crushed in food or fluids
Children under 1 month ¼ tablet dissolved in fluids (1 single dose only)


If necessary, and for younger children, tablets can be crushed in food or dissolved in fluids. In case of overdose, get medical help or call the Ontario Poison Centre immediately at 1‑800‑268‑9017 or 416‑813‑5900. The risk of side effects from taking a dose of KI is extremely low for all age groups who have normal thyroid function. The overall benefit during a nuclear emergency outweighs the risks of side effects. There is an increased risk of side effects for people with thyroid disorders i.e., auto-immune thyroiditis, Graves’ disease, iodine deficiency and nodular goiter. These disorders are more common in adults and the elderly, and are rare in children. Rare side effects in other parts of the body, such as gastrointestinal effects or hypersensitivity reaction, may occur but are generally mild. People who are sensitive to iodine, who have an existing or previous thyroid disorder, or have any other concerns, should consult their doctor or nurse practitioner prior to taking KI.

When stored in a dry location between 15 and 30 degrees Celsius, the KI pills are effective for up to 12 years. KI pills are available to children at schools in the 10 km zone, and select institutions in the 10 km zone such as health care facilities. KI tablets will also be available to the public at evacuation reception centres, and other locations designated by emergency officials. If you want to know more about the KI distribution program in Durham Region, please call 1‑888‑777‑9613; in Toronto you may call 311. If you have any health questions related to KI pills, please discuss it with your health provider or you can contact Telehealth Ontario at 1‑866‑797‑0000. Share this poster will all your neighbours (click here: KIposter).

Emergency Management Branch, Ministry of Health and Long-Term Care (2014). Potassium Iodide (KI) Guidelines provides more useful information.

The Pickering Nuclear Generating Station is located on the shores of Lake Ontario just east of Toronto. This is one of the world’s largest nuclear generating facilities. Darlington Nuclear Generating Station is located in the Municipality of Clarington in Durham Region, 70 km east of downtown Toronto.

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