The Chernobyl accident in Ukraine, 30 years after
The 26th of April 2016 marks the 30th anniversary of the accident in Unit 4 of the Chernobyl nuclear power plant in Ukraine, which resulted in a very large release of radionuclides which were deposited over a very wide area in the Northern Hemisphere, particularly in Europe and, most particularly, in Belarus, Northern Ukraine and part of Western Russia.
Much work has been conducted immediately after the accident and in the 30 years since in order to secure the area, limit the exposure of the population, provide support and medical follow-up to those affected and study the health consequences of the accident.
Several international conferences and meetings are being organised to draw lessons from 30 years of follow-up, including:
- A conference in Kiev, Ukraine, “Health effects of the Chornobyl Accident – 30 years aftermath” was held on 18 to 19 April 2016, organised by the Ukrainian National Research Centre for Radiation Medicine. It gathered leading experts in the fields of radiation biology and medicine, health care professionals, decision makers, as well as experts in radiation emergency and medical preparedness to analyse the 30-year experience of Chornobyl studies with the special attention to the effects of low dose ionizing radiation;
- A UN sponsored conference “Chernobyl 30 years on. From the accident to recovery and sustainable social and economic development of the affected areas” will be held on 25-26 April 2016 in Minsk, Belarus. Participants will review the progress made during the UN Decade of Recovery and Sustainable Development of the Affected Regions (2006-2016);
- A special meeting of the 70th session of the UN General Assembly on 26th April 2016 in New York commemorating the 30th anniversary of the Chernobyl Disaster.
- An International Conference "Health Effects of Chernobyl: Prediction and Actual Data 30 years after the Accident", will be held on May 17-19, 2016,in Obninsk, Russia, also focusing on lessons learned about health effects of ionizing radiation, particularly in terms of radiation biology and ecology, radiation epidemiology and dosimetry, radiation protection and safety, as well as matters pertaining to radiation emergency medicine and public health.
- An international “Scientific Symposium - Chernobyl: 30 years after” will be held at the WHO International Agency for Research on Cancer, in Lyon, France on 11 June 2016, to review current knowledge about the long-term health consequences of the accident and to discuss future research directions to improve our understanding about low-dose radiation effects on human health.
What have we learned in 30 years
The Chernobyl accident resulted in many millions of persons being exposed to ionising radiation in the most contaminated areas of Belarus, Russia and Ukraine. Some populations have undeniably sustained health impacts from the radiological consequences of accidents, in particular early emergency workers in Chernobyl who suffered acute radiation syndrome and young people who developed thyroid cancer as a result of fallout from that accident. Increases in leukaemia and thyroid cancer risk, as well as in the incidence of cataracts, have also been observed, but to a lesser extent, among those who participated in the clean-up of the accident, the so-called “Chernobyl liquidators” and there are suggestions of increased risk of breast cancer in young women in the most contaminated areas and of cardiovascular and cerebrovascular diseases among the liquidators. There have also been numerous reports of other health effects but lack of appropriate dosimetry and methodological limitations prevent their interpretation at this point.
Many others, however, have suffered serious consequences that were not directly related to the biological effects of radiation, but rather induced by the event itself, the presence of radioactive contamination and consequent emergency and remediation measures taken, and/or uncertainties about radiation levels and health effects. These include liquidators who developed anxiety, depression, post-traumatic stress disorders and suicide ideation; and evacuees and residents of contaminated areas whose lives were affected by emergency and/or remediation actions taken, and who continue to experience social and economic disturbances resulting from raised levels of radioactivity in the environment.
Apart from the direct and indirect health effects of Chernobyl, a very important aspect is the enormous socio-economic cost of the accident and of its remediation, in particular the cost of decontamination and containment. While a “sarcophagus” was built around the damaged reactor in 1986, it was built as a temporary containment measure, for a period of approximately 30 years. For years now, workers toil to reinforce walls and patch holes to prevent radioactive dust from escaping, while the construction of the new Safe Confinement – at an estimated cost of 1.5 billion euros (Wikipedia – 22/04/2016) –, the construction of which was initially announced shortly after the 10th anniversary, is yet to be completed.
Health effects - the future:
For decades now, the international research community has been recommending the establishment of a secure and coordinated funding and organizational mechanism for research on the health consequences of the accident. Through it is 30 years since the accident, there are a number of reasons why this is still needed:
- Health effects from this European accident continue and future effects are uncertain.
- Past knowledge of radiation effects is largely based on atomic bomb studies, but Chernobyl involved a very different type of exposure.
- Assumptions on the risk of low dose exposure have been challenged by recent advances in radiobiology.
- Estimates of deaths due to the Chernobyl accident vary widely.
In 2011, the EC funded ARCH project, coordinated by the WHO International Agency for Researh on Cancer, published its strategic research agenda for long term research on health effects of Chernobyl (1, 2). This included the establishment of a virtual Chernobyl Health Effects Research Foundation, similar to the Radiation Effects Research Foundation set-up in Hiroshima and Nagasaki some years after the atomic bomb exposures in Japan, together with a series of individual studies covering the main health consequences. These include the ongoing thyroid cancer problem, the reported rise in breast cancer, inherited molecular-genetic alterations, and various cancers, cataracts and other non-cancer diseases in liquidators and in the general exposed population. Long-term studies of already existing groups with known radiation doses would provide invaluable information on the life-time risks of both external and internal exposure.
As concluded by ARCH: “Unless such coordinated studies are set up, together with a mechanism to ensure long-term funding, the long-term consequences of a nuclear accident involving the exposure of many millions of people to radiation will not be properly studied, speculation will flourish, and knowledge essential to assessing the risks of radiation exposure will be lost”.