The Canadian Nuclear Safety Commission has recommended that the government issue potassium iodide pills to all people living within 10 km (6 miles) of nuclear power plants, to use in case of a nuclear accident, such as the one suffered by Japan's Fukushima Daiichi plant in 2011.
Following the Fukushima disaster, the Canadian Nuclear Safety Commission was directed to draft a report to help Canada make a plan for how it should respond in the case of a similar disaster at one of its own nuclear plants.
Current measures failing
If taken immediately after a nuclear disaster, potassium iodide tablets flood the thyroid gland with iodine, preventing the gland from absorbing radioactive iodine. Those who do not immediately take the pills are likely to absorb large amounts of radioactive iodine from the air, the water and food in the days following a nuclear disaster, dramatically increasing their risk of thyroid cancer. The thyroid glands of young children are particularly vulnerable.
The new Canadian recommendations are in line with policies in many other nuclear-powered nations, which directly distribute potassium iodide tablets to people living near nuclear power plants. Residents then store the tablets in their homes to use in case of disaster.
In contrast, Canada's current policy merely makes the tablets available at local pharmacies, with additional supplies stockpiled at schools. However, according to a 2013 survey by Ontario Power Generation of residents living near the Darlington and Pickering nuclear plants, "almost no one had obtained free pills that have been advertised in regional communications or pamphlets."
The nuclear commission is recommending that, instead, tablets be directly distributed to all residents living within 10 km of a nuclear plant. The nuclear industry has pushed back against such recommendations, in part because they would include roughly a quarter of a million people in the Greater Toronto area.
The decision was welcomed by environmental and nuclear watchdog groups, however, which have noted that the aftermath of a major nuclear disaster would not be a good time to efficiently distribute any type of medication and that the current policy is clearly not getting pills into people's hands.
"Our response is that we've had 30-plus years of making the pills available ... for people to pick up at pharmacies, and there's very low awareness by people that they should do so and that it matters to their health," said Theresa McClenaghan of the Canadian Environmental Law Association.
"Instead the messaging that people have had is that the plants are safe and there's nothing to worry about."
Current U.S. policy is even weaker than Canada's policy, with individual states merely "encouraged" to maintain potassium iodide stockpiles.
Only a half-measure
In terms of protection from radioactive fallout, however, potassium iodide is only a half-measure. It protects the thyroid gland from radioactive iodine isotopes only for as long as it is being taken regularly. Since I-131 has a radioactive half-life of only eight days, potassium iodide is considered a feasible protection against this isotope.
A recent study in Geochemical Journal, however, found that the Fukushima meltdowns actually released 31.6 times as much I-129 as I-131. I-129 has a radioactive half-life of 15.7 million years.
In addition, potassium iodide would offer no protection against cesium-137, the major radioactive isotope released from the Fukushima disaster. While not nearly as long-lived as I-129, cesium-137 has a half-life of 30 years.
According to a recent study, 50% more cesium-137 was actually released from the Fukushima plant than had previously been reported by plant operator Tokyo Electric Power Company (TEPCO). The study estimates that about 15,000 terabecquerels were ejected directly into the atmosphere, with another 3,500 flowing directly into the ocean. Up to 400 terabecquerels fell to land in North America. A terabecquerel is one trillion becquerels.
Following the Fukushima disaster, the Canadian Nuclear Safety Commission was directed to draft a report to help Canada make a plan for how it should respond in the case of a similar disaster at one of its own nuclear plants.
Current measures failing
If taken immediately after a nuclear disaster, potassium iodide tablets flood the thyroid gland with iodine, preventing the gland from absorbing radioactive iodine. Those who do not immediately take the pills are likely to absorb large amounts of radioactive iodine from the air, the water and food in the days following a nuclear disaster, dramatically increasing their risk of thyroid cancer. The thyroid glands of young children are particularly vulnerable.
The new Canadian recommendations are in line with policies in many other nuclear-powered nations, which directly distribute potassium iodide tablets to people living near nuclear power plants. Residents then store the tablets in their homes to use in case of disaster.
In contrast, Canada's current policy merely makes the tablets available at local pharmacies, with additional supplies stockpiled at schools. However, according to a 2013 survey by Ontario Power Generation of residents living near the Darlington and Pickering nuclear plants, "almost no one had obtained free pills that have been advertised in regional communications or pamphlets."
The nuclear commission is recommending that, instead, tablets be directly distributed to all residents living within 10 km of a nuclear plant. The nuclear industry has pushed back against such recommendations, in part because they would include roughly a quarter of a million people in the Greater Toronto area.
The decision was welcomed by environmental and nuclear watchdog groups, however, which have noted that the aftermath of a major nuclear disaster would not be a good time to efficiently distribute any type of medication and that the current policy is clearly not getting pills into people's hands.
"Our response is that we've had 30-plus years of making the pills available ... for people to pick up at pharmacies, and there's very low awareness by people that they should do so and that it matters to their health," said Theresa McClenaghan of the Canadian Environmental Law Association.
"Instead the messaging that people have had is that the plants are safe and there's nothing to worry about."
Current U.S. policy is even weaker than Canada's policy, with individual states merely "encouraged" to maintain potassium iodide stockpiles.
Only a half-measure
In terms of protection from radioactive fallout, however, potassium iodide is only a half-measure. It protects the thyroid gland from radioactive iodine isotopes only for as long as it is being taken regularly. Since I-131 has a radioactive half-life of only eight days, potassium iodide is considered a feasible protection against this isotope.
A recent study in Geochemical Journal, however, found that the Fukushima meltdowns actually released 31.6 times as much I-129 as I-131. I-129 has a radioactive half-life of 15.7 million years.
In addition, potassium iodide would offer no protection against cesium-137, the major radioactive isotope released from the Fukushima disaster. While not nearly as long-lived as I-129, cesium-137 has a half-life of 30 years.
According to a recent study, 50% more cesium-137 was actually released from the Fukushima plant than had previously been reported by plant operator Tokyo Electric Power Company (TEPCO). The study estimates that about 15,000 terabecquerels were ejected directly into the atmosphere, with another 3,500 flowing directly into the ocean. Up to 400 terabecquerels fell to land in North America. A terabecquerel is one trillion becquerels.
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