Pauline Gareau explains how to mitigate the effects of radiological contamination

The expansion of nuclear power in many countries, including many under construction in Asia, as well as permanent nuclear submarines, pose the risk of nuclear accident or terrorist attack, including the sabotage of a nuclear power plant with the intent to release radiation into the environment. Preparation to protect populations – especially infants, children and adolescents – is vital to mitigate the effects of radiological exposure

In addition to terrorist attack, preparations must also be made for a nuclear power plant (NPP) accident, which is a far higher risk. In both examples of exposure, significant supplies of antidotes and treatments are essential for immediate use.

Without stockpiling of these treatments, emergency services would be unable to rescue and protect populations from a nuclear release following a nuclear incident and it will be increasingly difficult to procure those life-saving medicines.

Today, each country must take on its own public health responsibilities when it comes to protecting their populations from the risks of nuclear contamination. Countries can be inspired by international communities’ guidelines and country-led initiatives. Examples are France’s regional strategy around nuclear plants, where the perimeter of potassium iodide distribution has been extended from 10 km to 20 km as well as the allocation of these same tablets to the public at large in Germany.

Multiple radioactive elements are often the source of radiological contamination. For example, following the Chernobyl and Fukushima disasters, cesium-137 and iodine-131 made up most of the harmful contaminants in the atmospheric dispersion and fallout.

Exposure is defined by an individual’s proximity to material emitting ionizing radiation, also defined as external contamination – for example, being in proximity to a nuclear plant explosion or being exposed through contaminated winds.

Health consequences
Ionizing radiation may interact directly with target tissues or indirectly through the production of free radicals. Actually touching, inhaling, or swallowing that material comprises contamination and is also defined as internal contamination. Internal contamination with radioactive material can expose patients to prolonged radiation, thus leading to short- and long-term clinical consequences.

Exposure may occur to the whole body – as external radiation from natural background exposures or radiation emergencies – or may involve partial body exposure, such as from medical radiography (X-rays) and most forms of radiotherapy.

Whether a person is exposed to external or internal radiation contamination, the body cells are affected identically throughout the ionizing radiation process. It is important to assess internal contamination levels to evaluate whether the patient has taken up hazardous amounts of the material delivering a significant dose of radiation to the body. Or to specific organs, such as the thyroid gland in the case of radioactive iodine. The clinical concern includes also long-term consequences, most notably, cancer – which may result from cumulative radiation doses over time.

Children are vulnerable
Children are likely to experience higher external and internal radiation exposure levels than adults because of their smaller body and organ size and other physiological characteristics. They are also more likely to pick up contaminated items and consume contaminated milk or foodstuffs.

Other types of cells (muscle, bone, and nerve cells) are less sensitive to the effects of ionizing radiation. DNA appears to be the principal target for biological effects of radiation, including cell death, mutation, and carcinogenesis. If the DNA repair is incorrect, it can result in cell death, chromosomal instability, mutation, or carcinogenesis.

Rapid treatment
Rapid initiation of treatment of contaminated patients is imperative after a radiological release event. Properly completed, rapid decontamination can reduce morbidity and mortality, limit the spread of contamination, and keep hospital emergency departments functioning for the treatment of other patients.

Internal decontamination can be achieved by several methods, including the blockade of enteral absorption, blockade of end-organ uptake, dilution, and chelation. Speed is of the essence because some isotopes can be incorporated by body organs within an hour of exposure and are very difficult to remove.

For example, as recommended by the WHO (Word Health Organization), provision of potassium iodide to people who are at risk of exposure to radioiodine should be implemented as an urgent protective action, within the framework of an optimised protection strategy. Therefore, having appropriate stocks at a national level, in hospitals, first-responders units and essentially, nearby NPPs – is the most important measure to prepare for widespread radiological exposure.

The optimal period to administer stable iodine is less than 24 hours prior to, and up to two hours after, the expected onset of exposure. This short open timeframe underlines the importance of having stocks of stable iodine at hand for immediate use.

SERB Specialty Pharmaceuticals has expanded its Emergency Care portfolio with the full market authorisation of 65 mg potassium iodide in the United States and European countries. Manufacturing is based in France with the essential capability to answer international needs.

ThyroSafe potassium iodide 65 mg is a FDA OTC (over-the-counter) and bid invitation product-approved thyroid blocker indicated as a vital treatment to prevent radioactive iodine from entering the thyroid gland during a nuclear radiation emergency. Tablets are quadrisected and comprise a full treatment compliance in infants and children and adults. Potassium iodide is used along with other emergency measures recommended by public officials.

Pauline Gareau is International Product Manager of the Emergency Care franchise at SERB. She joined the company in 2020 after working in several pharmaceutical industries as Brand Manager and Medical Science Liaison.

Image: A patient is tended by CBRN medical experts.