Nuclear risk: iodine, what for?

The European Commission is helping Ukraine following a request for help to build up a stockpile of potassium iodide tablets. 5.5 million tablets, of which 5 million come from European strategic reserves (rescEU reserves) and 500,000 from Austria have therefore been collected. Why, in such cases, is it recommended to take iodine? Is it effective? Should we store it at home or are distributions planned if necessary in France?

Iodine, a prevention against the occurrence of thyroid cancer

When a nuclear reactor malfunctions, as unfortunately seems to be the case since March 11 in Japan, it can emit radioactivity (leak at the containment level, explosion, etc.). This radioactivity is in particular in the form of radioactive iodine, which will reach people near the contamination zone. This iodine tends to settle on the thyroid, which considerably increases the risk of thyroid nodules, cancer of this same gland or occurrence of hypothyroidism. The rapid ingestion of iodine tablets reduces this risk: the iodine ingested will bind to the thyroid and saturate its receptors, which will prevent the bad (radioactive) iodine from binding.

How much iodine should I take?

Preventive iodine is available in the form of potassium iodide tablets, to be taken all at once as quickly as possible. To bring about a reduction of more than 90% in the fixation of radioactive iodine, the necessary doses are: – in the region where the dietary iodine intake is “normal“: 1 dose greater than or equal to 30 mg of iodine , – in regions where there is a relative deficiency in dietary iodine (case of France): 50 to 100 mg of iodine. In practice, a single dose of 130 mg is recommended, i.e. 2 tablets, to be dissolved in a glass of water (1 tablet for children under 12 years old, ½ tablet for infants from 1 to 36 months, a quarter of a tablet for newborns less than 1 month).

When should these tablets be taken?

Ideally, these tablets should of course be taken as soon as the alert has been given to obtain an effectiveness close to 100%. In the so-called “iodine-rich” regions, 2 hours after the onset of contamination, the effectiveness of protection is still 80%, and 40% 8 hours later. In “iodine-poor” regions, the protection is 65% and 15% respectively.

In France, how to get such tablets if you live near a nuclear power plant?

The large number of nuclear power plants in France, which are often aging, poses a threat to our country, as environmentalists have been reminding us for decades, particularly in the event of an accident, tsunami, a major earthquake or a terrorist attack. Faced with these risks, admittedly minimal but impossible to deny or neglect, the Nuclear Safety Authority and the public authorities regularly organize campaigns to distribute iodine tablets to the populations and communities residing near a power plant, with the financial support from EDF. Thus, the persons concerned could, if the warning sirens of a power plant sound, take the tablets immediately.

How does this distribution work in practice?

This distribution is intended for families and communities (schools, town halls, companies, hotels, etc.) located within a perimeter of 10 km around each French nuclear power plant, i.e. approximately 400,000 households and 2,600 establishments open to the public spread over 500 municipalities. . The people concerned receive a voucher and are invited to collect their tablets from the pharmacy. The last campaign of this type took place in 2009, with only partial success, according to distribution-iode.com : only 22.5% of managers of companies and communities located within a perimeter of 10 km around a nuclear power plant went to a pharmacy to collect their tablets, compared to 51.9% for individuals.

Summary of this information and additional details on these tablets and how to take them by Dr Doré, pharmacist :

Mr. Dore. Pharmacist by demonstration-video

The information leaflet of the Nuclear Safety Authority :

Nuclear Safety Authority IODE_depliant2009

In addition to this prevention by iodine, which will probably be reinforced following the Japanese tragedy, the main way of reducing the risks is evacuation within a perimeter of 10 to 20 km from the plant, which has moreover been made quickly in Japan, despite the difficulties linked to the damage to the infrastructure. Beyond the prevention of the immediate and delayed risks of the current overheating of the reactors, this dramatic episode risks having a lasting impact on the perception of nuclear energy, so far often qualified as “sustainable”, even “ecological”. by its promoters, in particular French… Jean-Philippe Rivière

Sources:
– The information site distribution-iode.com, published by the ASN (Nuclear Safety Authority). – POTASSIUM IODIDE PCA tablets page on Doctissimo

Photo :
The level of radioactivity checked on a child evacuated from the area surrounding the Fukushima power plants, March 13, 2011, © Wally Santana/AP/SIPA