Chernobyl - 20 years after

Chernobyl nuclear power plant after the explosion
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For days after the explosion at the Chernobyl nuclear power station, on April 30th, 1986, Czechoslovak Radio announced that the situation at the power plant was improving. Precisely at that time the radioactive cloud had reached Czechoslovakia.

It is one of those occasions where everyone remembers what they were doing when the news broke. At least I do. Together with hundreds of thousands of people across Czechoslovakia I was at a compulsory May 1st demonstration - standing outside in the rain which was bringing down radioactive iodine as the cloud had just hit this country.

Dana Kuchtova is an anti-nuclear activist and now a deputy chairwoman of the Green Party.

"The Czechoslovak authorities did not warn the citizens. As late as April 30, the state news agency issued a report that no increase in radiation had been monitored. Five days later another report said the 'non-existent' radiation level was falling. Unlike in neighbouring countries, people were not recommended to stay indoors, especially while it was raining."

Irena Malatova is from the National Radiation Protection Institute which has concrete data on radiation levels in Czechoslovakia following the Chernobyl disaster.

"It was measurable. However, the impact was just minor. The doses were relatively quite low, so it was not necessary to introduce any countermeasures for the protection of population. In spite of this some countermeasures were introduced but they were of such features that they did not influence the normal life of people. For example, it was recommended that dairy cows be kept in their sheds and not put out to pasture. Then, the production of baby formula was transferred from one factory to another one because the first one was surrounded by pastures with higher contamination. So the activity of Caesium 137 and 134 was higher in this place."

It was not only caesium that was monitored on Czechoslovak territory.

"The most important, of course, was iodine 131, then Caesium 137 and 134, also tellurium 132 and iodine 132 was measurable. We could also measure ruthenium 103 in the environment and people. There were some other radionuclides which we were able to measure in aerosols or in deposits on the ground but their significance from the point of view of the doses to people was less than, for example, of iodine and caesium."

It is iodine 131 that has been blamed for the loss of several hundred male babies in Czechoslovakia. Dr Miroslav Peterka from the Institute of Experimental Medicine in Prague believes they were miscarried after their mothers were exposed to radioactive fallout during a specific period of pregnancy in which foetuses are particularly vulnerable to radiation exposure.

"We think that the most critical period for radiation exposure is the third month of pregnancy. Our data about the third month of pregnancy being a critical period correlates with the results of Japanese studies after Nagasaki and Hiroshima."

Chernobyl nuclear power plant today,  photo: CTK
During unrelated research Dr Peterka discovered a singular irregularity in the newborn sex ratio which occurred in November 1986, seven months after the disaster. In that month fewer boys were born than girls, which had never occurred in the 50 years that records have been kept. Male foetuses are generally more vulnerable, and Dr Peterka believes their loss can be blamed on the post-Chernobyl radiation.

However, this hypothesis is disputed by some other experts who say no similar findings have been made elsewhere after Chernobyl and also the doses here, some 1,100 kilometres away from Chernobyl, were very small compared to even natural radiation that everyone is exposed to in the environment.

Today, there are two nuclear power plants in the Czech Republic, at Dukovany, which was built in the late 1980s, and at Temelin. Both not far from the border with fiercely anti-nuclear Austria. It is the Temelin plant that has received most publicity, mainly because opponents to nuclear power say it is potentially unsafe, combining Soviet design and western operating technologies. Dana Drabova is the chairwoman of the State Office for Nuclear Safety.

"First of all you have to have in mind that the Temelin reactors are of a very different design from the Chernobyl ones. There is no graphite to be burnt in the event of an accident. There is a pressure vessel containing the core of the reactor - there is no pressure vessel in reality in Chernobyl-type reactors. And what concerns the combination of technologies, I can see it even as a benefit because the original Soviet design of, say, the mechanical or machinery parts of the power plants, like the pressure vessel and so on, was very robust, with very high safety margins. And what was added is really state-of-the-art instrumentation and a control system. And to combine it is no problem, in my opinion, because if you know the algorithm and you can tell the system what to do, there is really no problem."

Mother of firefighter Vasily Ignatenko,  whose crew was the first to fight the fire at the Chernobyl nuclear plant when it's Reactor No. 4 exploded on April 26,  1986,  photo: CTK
It's been twenty years since the worst nuclear disaster in history. Dana Drabova of the State Office for Nuclear Safety says that however tragic the accident was, humankind has learnt its lesson from Chernobyl. And, she says, it is all the more true for the international nuclear community.

"There are quite a lot of different lessons. We can mention a lesson concerning the design of nuclear power plants, the design of reactors, the safety features of reactors but what is, in my personal view, the most important lesson, is the crucial role of the so-called 'human factor' and the reliability and role of the operators of such utilities as nuclear power plants. And the attention towards the training, towards the education, towards the responsibility of these people taking care of safe operation is now much, much better than it was before Chernobyl."