The greatest radiation-ecological catastrophe in the world took place 26 April 1986 about 140 km. from Kyiv, the capital of Ukraine. An explosion and radiation accident on the fourth block of Chornobyl Atomic Electric Power Station caused the catastrophe.

Medical, radiation-biological and dosimetrical problems appeared as a result of the catastrophe can not be compared with others, known in the world accidents of mass radioactive irradiation of the people (Japan, USA, Brazil, Russia) in measure of victims, in measure of structure and complicacy of radiation sources and in measure of existing complex of the unfavourable attendant circumstances of non-radiation origin.

The most radiation-damaged persons were those taking part in the fire extinguishing and emergency repairs at the station. Following information data in 1986 year 238 persons fell ill with acute radiation sickness, 29 from them died in the first time after accident. Near 2,000 persons caught local radiation damages. 90,000 persons were obliged to evacuate themselves from cities Chornobyl, Pripyat and from villages situated in 30 km. around zone. 50,000 persons more were moved later from the polluted territory.

Total radiation pollution due to the catastrophe covered area greater than 42,500 sq.km. Drinking and irrigation water of the Dnieper river basin had been exposed to ionizing radiation. In this area dwell about 30 million of the Ukrainian population. In 12 regions of Ukraine zones with density pollution of caesium 137 more than 1 Ci/sq.km. and those of strontium 90 more than 0.1 Ci/sq.km. have been determined. After dosimetry investigation of 6447 populated areas 93 of them have been related to 2d zone of obligatory evacuation and 800 of them--to 3d zone of voluntary evacuation according to Ukrainian laws. More than 1 million persons inhabit there.

Chornobyl disaster victims are subdivided into several types--those engaged in disaster liquidation in industrial sites of station and in 30 km. Chornobyl area (more than 200,000 persons including 120,000 liquidators in 1986-1987 years), those residing at the territory subjected to radiation (approximately 1.5 million persons) and considering Kyiv city and south territories where soil density pollution of caesium 137 exceeds 1 Ci/sq.km. total group can reach to 4.5 million persons.

The first result of medical registration of suffered people allowed to make an approximate assessment of dose loading on the thyroid gland among population of Kyiv oblast (region), Zhitomir oblast, Cherkassy oblast and Vinnitza oblast.

Due to this 7 million of population have been attributed to the at-risk group including 1.5 million children. 60% of cancer thyroid diseases related to this group have had the adults which were children or adolescents during Chornobyl accident. Analysis of the cancer thyroid cases among children and adolescents of Ukraine operated in age before 18 years showed that this age group had 59 cancer thyroid cases before 5 years of disaster, but in 1986-1995 years total number of sick persons which were children and adolscents during disaster formed 669.

Rate of morbidity growth is the highest among children operated in age before 15 years. During 1981-1985 years 25 cancer cases among children of Ukraine were registered and during 1986-1995 years this figure increased to 256. The general deterioration of health among persons subjected to ionizing radiation as result of Chornobyl accident incites alarm as well.

Chornobyl aftermathes causes increased morbidity rate of children especially of such diseases as neoplasms, diseases of blood creating organs, congenital anomalies, organs of sense, digestion organs, neurological disorders. The high morbidity rate is registered on diseases of respiratory organs and of endocrine system. A number of children considered as practically healthy has decreased every year. The health of about 20,000 children those were born from the persons engaged directly in liquidation of Chornobyl accident has caused high anxiety.

Besides the children, the persons engaged directly in liquidation of the disaster need great attention on the side of medical workers. The Ukrainian National Register of victims comprises data of 474,095 persons, 36,000 persons more are counted in the Military Medical Register of the Ministry of International Affairs and of State Security Service.

The National Register contains information on the health level of 184,672 liquidators (175,439 of them are men and 9,233 are women).

195 persons engaged in liquidation of Chornobyl disaster and received in 1986 year diagnosis "acute radiation sickness" have dwelt in Ukraine. The repeated diagnosis confirmed 145 cases of the sickness among them.

The analysis of the morbidity dynamics among liquidators testifies to negative changes. The average morbidity per 1,000 persons increased from 581% in 1983 year to 1,409% in 1994 year.

The disability rate caused by Chornobyl accident forms 2.9% of the total disability of adult people. The main causes of liquidators disability are diseases of blood creating organs - 47%, of the nervous system - 8.9%, of digestion organs - 10.1%, of neoplasms - 4.5%.

The changes in health of communities residing at the territory contaminated with radionuclids are revealed. Due to medical examinations the healthy persons among them formed 56.8% in 1987 year and 24.2% in 1994 year.

Tendency toward health level deterioration is conditioned by rising or morbidity rates for the most types of diseases.

In the dynamics of investigation the general morbidity rate of adult people residing in controlled territories enhanced more than in three times.

Chornobyl disaster exerted influence upon the birth-rate. Number of complications during pregnancy and delivery have been augmented; figures of children mortality, of general morbidity, of congenital anomalies have been also increased.

In the morbidity structure of all victims cardiovascular diseases take the first place, the second place - in evacuated persons - have oncologic diseases, traumas, poisonings and accidents are usual among liquidators.

For the last five years important international projects as AIFEKA and Medical Problems of Chornobyl were carried out in Ukraine under the auspices of the World Health Organization.

Dispensary registration of the persons subjected to ionizing radiation is fulfilled in the Zhytomir oblast and Rivne oblast with the assistance of the international Red Cross (mobile diagnostic laboratories are used).

The French society Children of Chornobyl created in Kyiv a diagnostic centre providing help in the medical examination and treatment of children.

According an agreement between the Health Ministry of Ukraine and the Health Ministry of Cuba in 1990 year 14,600 children and 2,000 adults were sanitated in Cuba. In conformity to the order of the President of Ukraine dated 1 April 1996, the international centre "Eupatoria" destined to the children sanitation is opened in the city of Eupatoria.

The implementation of the programme "UNESCO-Chornobyl" contributed to the equipment of a children hematology centre.

A solid scientific programme is accomplished by the project of European Community. The humane help from Germany, Italy, France, Israel, Japan, USA and from other countries is very appreciated in Ukraine.

We are very much obliged to the help received from organizations and funds Children of Chornobyl (USA, Zenon and Nadiya Matkivsky), Ukrainian Fraternal Union in USA, from our brothers and sisters of Ukrainian community in Canada, etc.