Keynote address at the International Conference 25 Years After the Chernobyl Accident: Safety for the Future

Mr President,
Excellencies,
Dear colleagues,
Ladies and gentlemen,

For me it is a great honour to be here today to represent WHO Director-General Margaret Chan and to convey to you her greetings and message.

Twenty-five years ago, the Chernobyl accident, the most severe civilian nuclear accident in human history, hit the heart of Europe, causing alarm and concern in the whole continent for its health, environmental and social consequences.

The magnitude of the effects of the accident, and particularly the health effects, has been subjected to extensive debate and controversy in the scientific and decision-making community.

Indeed, the uncertainty surrounding the health effects has contributed to increase the alarm in the affected communities as well as the sense of hopelessness towards a threat to health that was perceived as uncontrollable, threatening present and future generations. In many cases, Chernobyl has become the “explanation” for several problems, indeed attributable to broad public health causes and aggravated by the difficult political, economic and social transition the affected countries have experienced in recent years.

WHO has worked with many partners at the national and international levels to build a solid and shared evidence base on the health effects of the accident. The data are summarized in two landmark reports published by the United Nations Chernobyl Forum in 2006 and recently by the United Nations Scientific Committee on the Effects of Atomic Radiation, which reviewed the latest available information. These two reviews are essentially consistent and emerge from comprehensive assessment of the existing scientific evidence based on national and international studies. We should thank here today the thousands of scientists and public authorities in the countries as well as international organizations that have made these assessments possible over the years through their daily efforts: gathering data, treating patients and accumulating the knowledge that is necessary to move away from myths and perceptions.

In summary, in the most severely affected countries, about 6000 people who were children and adolescents in April 1986 have been diagnosed with thyroid cancer so far. New thyroid cancer cases are expected in the coming decades among those exposed in 1986, although the magnitude of the risks and the number of future cases are difficult to quantify.

The likely excess number of cancer deaths due to the Chernobyl accident occurring in the lifetime of clean-up workers, evacuees and residents of the highly contaminated and less severely contaminated regions in Belarus, the Russian Federation and Ukraine (about 6 million people) has been estimated to be as many as 9000, about 1% cancer deaths more than the number (about 1 million) expected in these populations. Of these 9000, 4000 excess cancer death cases are expected among the 600 000 most severely exposed people, corresponding to a 3.5% increase over the background cancer mortality rate.

It has been argued during recent years and even very recently that these numbers are much lower than those predicted earlier. This is true, and a few considerations need to be made. First, our assessment of the magnitude of the effects is based on solid scientific evidence generated by well-designed, well-conducted and well-analysed studies. In addition, we also believe that some of the effects of the accident may have been mitigated by the prompt action of the liquidators, the rapid evacuation of people in the affected areas and the distribution of stable iodine tablets, which substantially reduced the uptake of radioactive iodine in some areas. However, these numbers do not mean that the health effects of Chernobyl have been mild or acceptable. Thousands of cancer cases caused by the accident are an unacceptable price paid by the affected communities in the attempts to achieve economic development. An environmental catastrophe of this dimension does not become more acceptable if, instead of hundreds of thousands, thousands of people develop a disease or die.

On top of these deaths and illnesses, the largest quantitative health effect of the Chernobyl accident in terms of the number of people affected is on mental health. The exposed populations have anxiety levels that were twice as high as controls, and they were 3–4 times more likely to report multiple unexplained physical symptoms and subjective poor health than were unaffected control groups. These effects have been attributed mostly to a lack of accurate information at the time of the accident and afterwards.

This level of psychosocial impact was indeed unexpected. The Chernobyl accident has been perhaps the first case showing this clearly the importance of public communication on public health risk management not only for ethical and political reasons but also as an instrument to prevent public concerns, health effects and expensive long-term studies. This lesson should be kept in mind by those who are facing the crisis in Japan and the release of radioactivity from the Fukushima Nuclear Power Plant: information, transparency and accountability are the keywords in this and other similar situations.

Twenty-five years after the accident, the national and international communities are moving the policy agenda from the Chernobyl-related needs towards a more holistic view of the requirements of the individuals and populations concerned. This is enabling the affected communities to be more empowered in the transition towards more proactive development.

Within this overall framework, WHO has actively contributed to the International Chernobyl Research and Information Network (ICRIN). ICRIN has drawn on the findings of the United Nations Chernobyl Forum to disseminate scientific information in language that non-specialists can understand, and several projects and activities have been geared towards supporting the affected communities to take control of their lives and put the accident behind them. Putting the radiation risks in proper perspective would allow public health authorities and citizens to direct resources towards the more pressing public health problems of these communities.

However, the specific health needs of the affected populations will continue to require attention and follow-up, such as health care for the workers who recovered from acute radiation syndrome and other highly exposed emergency workers. Population subgroups known to be particularly sensitive (such as children exposed to significant amounts of radioiodine or who resided in 1986 in the areas with radioactive fallout) should be considered for screening of specific outcomes, such as thyroid cancer, keeping in mind the cost and benefit of each programme. Population health should continue to be monitored through cancer registries and follow-up studies to describe trends and address priorities.

Mr President, ladies and gentlemen,

The effects of the Chernobyl accident on health have been dramatic and different than expected in some important aspects. The accident has posed a tremendous health, social and economic burden on the affected countries.

We are confident that the United Nations System and the Member States will continue their efforts to ensure that all stakeholders undertake action towards reconstruction, development and better health. WHO continues to be ready and willing to support these efforts.