Is it time to get real about radiation?

It's 1.23am, 26 April, 1986. The snow is melting, spring is emerging and in Ukraine this goes quickly. By the end of April, you can expect to be swimming in the river and barbecuing. Operators at the Chernobyl nuclear power plant thought they were coming to the end of a gruelling 24 hours of running tests.

In fact, Chernobyl was just entering a new phase in its existence and the future of nuclear engineering. In just four seconds, power surged to 100 times the reactor's capacity. The uranium fuel disintegrated, bursting through its cladding, coming into contact with cooling water. An enormous steam explosion smashed over 1,500 water pipes, throwing aside the reactor's cap, blowing through concrete walls and throwing burning blocks of graphite and fuel into the compound. Radioactive dust rose high into the atmosphere. The rest, as they say, is history.

In May 1987, an article in National Geographic Magazine said that Dr Richard E. Webb, a nuclear engineer, calculated 280,000 possible deaths as a result of the Chernobyl accident contaminating a European area as big as Texas with caesium. Scientists from the International Atomic Energy Agency (IAEA) said that contamination in western Europe was spotty but figures were still being compiled. Dr Morris Rosen, the IAEA's safety director, called Chernobyl "an unacceptable accident - but tolerable for society". He argued that smoking and radon gas in homes were more serious threats than nuclear accidents. Western experts, using the limited data available to them, estimated that 24,000 people among the 116,000 evacuated received serious radiation doses of about 500 millisieverts (mSv). In general, 10mSv is now considered acceptable for a nuclear-plant employee in one year. As of 2004, the total number of fatalities is 50 (IAEA Chernobyl Forum Report).

The Soviet Union did not acknowledge the disaster until two days after it happened, on 28 April. During this time in Europe, civil defence teams were called up in the midst of fear and panic caused by a lack of accurate information quickly communicated. The inability or unwillingness of the Soviet Union to 'own up' to the fact that this accident had happened, to quickly ascertain the facts and to disseminate information to the rest of the world led to speculation on a grand scale.

In 1989, the World Health Organisation (WHO) first raised concerns that local medical scientists had incorrectly attributed various biological and health effects to radiation exposure. An authoritative UN report in 2000 concluded that there was no scientific evidence of any significant radiation-related health effects to the majority of people exposed. The 2005 Chernobyl Forum study involved more than 100 scientists from eight specialist UN agencies and the governments of Ukraine, Belarus and Russia. Its results are in line with the United Nations Scientific Commission on the Effects of Atomic Radiation (UNSCEAR) 2000 report which said that "there is no scientific evidence of increases in overall cancer incidence or mortality or in non-malignant disorders that could be related to radiation exposure". Yet exaggerated figures continue to be published regarding the death toll attributable to the Chernobyl accident. One such publication from the UN Office for the Co- ordination !

of Humanitari an Affairs is entitled Chernobyl - a continuing catastrophe. The UNSCEAR chairman has made it clear that "this report is full of unsubstantiated statements that have no support in scientific assessment".

Misinformation continues to abound, fuelling misjudgements and misgivings when it comes to nuclear power plants.

Nuclear power is a clean source of energy with a dirty name due initially to the Soviet Union's unwillingness to wash its soiled linen in public. A fresh look at nuclear power can mean a fresh start for the nuclear industry. The UK's Department of Trade and Industry has actively supported the International Chernobyl Centre (ICC) for the last decade. Trevor Hayward, assistant director for the former Soviet Union nuclear programme, said: "We became involved under the Nuclear Safety Programme, establishing the ICC as a scientific research centre to examine and record the exact facts emerging from the accident in 1986. Over 140 projects have been implemented. We also introduced a programme to manage the social and economic consequences of nuclear power plant closure, a fact which is often overlooked."

Slavutych, the new town created following the evacuation of Pripyat and other villages in the region now known as the Exclusion Zone, is thriving with the help of international funds used to help implement such projects as the Business Development Agency, Community Development Centre and a Credit Union. Town Mayor Volodymyr Udovychenko is the driving force behind economic and social progress and can be justly proud of this town where unemployment is relatively low compared with other parts of the Ukraine and which is second only to Kiev in terms of per capita investment. Slavutych is not the only 'phoenix' to rise from the ashes of Chernobyl; the Exclusion Zone is becoming a haven for rare birds and flora and fauna are overtaking the scorched earth. Nature is resilient.

The pages of the Chernobyl story have been slowly turning over the last 20 years. It is a continuing story which we should all read before making up our minds. But remember, during a three-hour flight to our holiday destination, we will 'pick up' extra cosmic radiation. Sitting on a rocky beach, we receive more terrestrial radiation. Relaxing in front of the TV on our return, we can reflect that the additional natural radiation from our holiday may be equivalent to as much as 10% of our normal average dose of 2-4mSv per year. Let's put radiation where it belongs - in perspective.

• Mary Donovan is the editor of INSIGHT, the official journal of the International Chernobyl Centre.

Major analysis feature on the 1986 nuclear disaster at the Chernobyl power plant and the dispute over how to assess its long-term implications for the region and for Europe.