Chernobyl as a diagnosis
Chernobyl as a diagnosis

Paraphrasing a well-known expression, we can claim: “Chernobyl has a beginning, Chernobyl has no end”. We still feel the consequences of the tragedy today. Moreover, even 34 years later, no one dares to insist that it will not mow down the next generations. Who are they? The victims of Chernobyl? Is their list growing and what are their prospects? Here’s what the experts say about it.

Dmitry Bazyka: Ukrainian medicine was not ready for such a large-scale catastrophe.

Director General of the National Scientific Center for Radiation Medicine, Doctor of Medical Sciences, Professor Dmitry Bazyka tells how today, 34 years after the Chernobyl disaster, Ukrainian doctors solve the problems of the “Chernobyl consequences”.

Where did Chernobyl hit hardest?

The consequences of the Chernobyl disaster on human health are multifaceted and are associated with both direct exposure to ionizing radiation and other negative factors of the accident. The generally recognized effect of radiation is cancer. Length of the latency period depends on the type of cancer and the radiation dose. For “early” oncological diseases, doctors include cancer of the thyroid and mammary glands, as well as leukemia.

The first recognized consequence of radiation exposure was an increased risk of developing thyroid cancer among the Ukrainian population affected by the Chernobyl disaster. A significant increase in its frequency among patients irradiated in childhood was recorded already 5 years after the accident. It is reliably associated with irradiation of the thyroid gland with iodine radionuclides.

More than 7,000 such patients under the age of 18 have been operated recently in Ukraine. At the time of the accident, 74% of them were in the age group under 14 years old. Joint research by the Institute of Endocrinology and Metabolism of the Academy of Medical Sciences of Ukraine and the National Cancer Institute of the United States established a causal relationship between the absorbed dose and the increase in the incidence of thyroid cancer among patients exposed to radiation in childhood and adolescence.

What are the statistics for the adult population?

The radiation risks of thyroid cancer in adults are still a matter of debate. There was an increased morbidity among liquidators and evacuees from the 30-kilometer zone. International pilot studies of this issue are ongoing.

Ukraine and other affected countries established an effective system of early diagnosis, treatment and rehabilitation. This helped to achieve significant successful results. However, the long-term results of treatment require further study. The quality of life of patients in the postoperative period decreases and such patients need long-term support.

Recently, international studies have established an increased risk of radiation-induced leukemia among Chernobyl liquidators. The identified risk levels were similar to those previously reported after the atomic bombing in Japan.

Also, the incidence of some types of solid cancers has increased among the liquidators and in certain groups of victims in recent years. For example, breast cancer among women liquidators in 1986-1987, as well as among women living in the most contaminated regions of Belarus and Ukraine. The results of studies of the affected population in Ukraine, Belarus and Russia indicate an increase in somatic mutations in the blood, in particular in children born to irradiated parents.

Evidence for the role of genomic instability, immunosuppression and other effects has increased. However, the scope of these studies is still insufficient. There is also some evidence of an increase in mortality from cardiovascular diseases among liquidators. However, their relationship with the radiation dose received is still a subject for further research.

Such a concept as “the complex of the victim of Chernobyl” has appeared. Is this condition amenable to medical correction?

The human psyche is closely related to the general state of the body. Therefore, constant psychological pressure can be one of the factors in the development of various stressful diseases. The population of our country has been under such pressure for many years. First, under conditions of uncertainty and lack of information. Then, due to the spread of information about the inevitability of severe consequences of radiation.

Such psychological pressure can lead to the formation of diseases and a “victim complex” even in the absence of radiation. Studies show that the population affected by the Chernobyl accident has long-term mental disorders, including depression, anxiety and post-traumatic stress disorder.

A whole complex of international studies is being carried out now to determine the relationship between impairments of cognitive function with the radiation dose and other negative factors of Chernobyl. Such factors as resettlement, restriction of production activities also negatively affected people’s health.

In addition, as a challenge of the time, it is worth accepting the fact that mortality among liquidators has increased, including from non-neoplastic diseases such as ischemic heart disease and associated pathologies, hematological diseases.

Can these challenges be resisted?

At the time of the Chernobyl disaster, Ukrainian medicine was unprepared to eliminate a nuclear catastrophe of this magnitude. But now, after 34 years of hard work to overcome its consequences, we can state a lot of positive developments:

  • a significant experience in radiation and hygienic control;
  • the creation of specialized dispensaries, departments and other specialized institutions in which experienced specialists work selflessly;
  • functioning of the State Register of Victims;
  • network of ultrasound, immunohematological diagnostics of victims.

As a result, the mortality rate from thyroid cancer does not exceed 1%, which indicates the high efficiency of its early diagnosis and treatment. The experience of Ukrainian doctors gained global significance when the accident at the Fukushima-1 nuclear power plant in Japan happened. Dozens of Japanese doctors and scientists came to study with us. They invited our professors to share their experience. To this day, methodological documents and monographs of our scientists are being translated into Japanese and are actively practiced Japanese colleagues.

We need to improve and develop medical assistance to victims of the Chernobyl accident.

As a doctor, I must emphasize that personal perception of the challenges of the time is also important. There are many of our compatriots who, despite the health problems associated with radiation, do not “enter” the disease, but they resist it with all their might.

Equally important is the creation of a group and individual psychological support service. This is quite unusual for our mentality, but effective in countering the consequences of Chernobyl. UNESCO and a few volunteer organizations have already organized such centers.

34 years behind

The radiation situation in Ukraine has changed somewhat for 34 years after the accident at the ChNPP. In particular, short-lived and medium-living radionuclides have disintegrated, and the amount of the main dose of the forming radionuclides has almost halved.

The main part of radioactive contamination is concentrated on the exclusion zone. Heterogeneity, a plurality of physicochemical forms of radioactive fallout, different long-term dynamics of bioavailability and migration capacity of radionuclides characterize the spatial distribution of radionuclides on the territory of the zone.

An exposure dose rate in some places of the exclusion zone, in particular on the northern and western traces of radioactive fallout, still exceeds the natural radiation background by hundreds of times.

The radiation situation changes in a wide range and even in certain areas within the zone. For example, it reaches a natural level of 16-23 microR / hour in the city of Chernobyl. Natural physical, chemical and biological migrations slowly change the general nature of environmental pollution due to the redistribution of radionuclides in it.

The consequences of the accident at the Chernobyl NPP became especially difficult for the population of the Polesie zone. The northern part of the Volyn, Zhitomir, Kiev, Rivne and Chernigov regions are the territories that have suffered from the greatest radioactive contamination.

Agriculture was the main sector of the regional economy in these regions. Natural landscapes such as meadows, pastures and forests provided a significant share of production. The consumption of locally produced food products formed the radiation dose to the population of these territories.

In recent years, these risk factors have persisted and become more complex against the backdrop of a nationwide economic decline. Now, the share of private farms in the total gross agricultural output is more than 75% in these regions.

At the same time, private households produce about 60% of meat and 75% of milk. Consumption of them causes the formation of up to 90% of the internal radiation dose of the population. The manufacturer uses these products and supplies to the consumer market of Ukraine.

The Zone is an open source of radioactivity

Today, the exclusion zone is an open source of radioactivity. The Zone has its own distribution structure, the presence of various forms and types of radioactive elements. As a result, the radiation factor continues to be one of the main factors in determining the potential danger, both for the population living in the territories adjacent to the zone, and for the population of Ukraine as a whole. And although the indicators of the radiation situation in the exclusion zone have changed significantly, almost 300 km2 of the territory within its limits will be unsuitable for human habitation for hundreds of years.

High levels of radioactive contamination of the territory will remain a long-term source of pollution of surface and ground waters due to surface washout and vertical migration.

Therefore, talking about the potential recovery of the population living on these lands is extremely thoughtless and unlikely, even from a theoretical point of view. Actually, practice shows that for most of these people, Chernobyl has become a congenital diagnosis, both literally and figuratively.