When the Chernobyl Nuclear Power Plant in Northern Ukraine exploded on April 26, 1986, the nuclear disaster threatened the whole of Europe. The nuclear disaster, triggered by a failed safety test, killed at last 30 people within three months of the blast and thousands more are believed to have suffered the effects of radiation. When the Chernobyl Reactor Four exploded at 1.23am local time on April 26, a raging fire pumped radioactive material into the atmosphere for 10 days straight. The World Nuclear Association estimates at least five percent of the reactor’s nuclear material leaked into the atmosphere.
What countries were affected by the Chernobyl disaster?
The Chernobyl reactor exploded a short distance away from the Soviet town of Pripyat in the Kiev Oblast, or region, near the border of Belarus.
The disaster produced the “largest uncontrolled radioactive release into the environment ever recorded” and mostly had an immediate impact on Ukraine, Belarus and West Russia.
Vast swathes of Belarus were contaminated by the explosion, rendering about a fifth of the country’s arable farmland unusable.
But the presence of strong winds in the atmosphere that night pushed radioactive fallout further into West Europe and Scandinavia.
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Just days after the nuclear incident occurred, raised levels of background radiation were being observed in places like Sweden.
The World Nuclear Association said: “Most of the released material was deposited close by as dust and debris, but the lighter material was carried by wind over Ukraine, Belarus, Russia, and to some extent over Scandinavia and Europe.”
According to the World Health Organization (WHO), approximately 7,722 square miles (20,000 square kilometres) of Europe were contaminated.
The exact impact of the contamination depended on whether it was raining when contaminated winds passed overhead.
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A lot of the radioactive strontium and plutonium particles released by Chernobyl, for instance, settled on the ground up to 62 miles (100km) from the exposed reactor.
Radioactive iodine, also released in the disaster, has a very short half-life and has decayed by now.
Some areas contaminated by radioactive strontium and caesium will remain a “concern for decades to come”.
The WHO said: “Although plutonium isotopes and americium 241 will persist perhaps for thousands of years, their contribution to human exposure is low.”
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A current concern remains in northern Europe and Scandinavia where herds of reindeer feeding on radioactive vegetation have left them inedible for humans.
These radioactive reindeer are found all across Sweden, Norway, Russia and Finland.
Experts have also found low-level radiation in lakes and rivers in Sweden and Germany but the radioactivity is mostly “not significant for humans”.
To date, Belarus, Ukraine and Russia suffered the worst effects of the nuclear disaster.
In 2005, the WHO estimated around five million people still lived in areas most contaminated by Chernobyl radionuclides.
About 100,000 of these people, lived in areas once deemed under “strict control”.
And since the Chernobyl disaster, experts have liked about 4,000 cases of thyroid cancer to the radioactive fallout,
A 19-mile-wide (30km) Exclusion Zone now surrounds the sheltered Chernobyl Power Plant.