Number and Structure of Participants in the Liquidation of the Consequences of the Chornobyl Nuclear Power Plant Accident (1986—2020)

Given the exceptional relevance of information on the number and structure of the population, which are the scientific basis for assessing the medical consequences of the Chornobyl disaster by the national and foreign community, the purpose of the study was to analyse the sources of information of the Ministry of Health of Ukraine for 1986—2020 regarding the number and structure of participants in the liquidation of the consequences of the Chornobyl NPP accident (PACL). Demographic, mathematical and statistical, graphical, comparison and generalisation methods were applied. For the first time, statistical data of the Ministry of Health of Ukraine on the number and structure of the PACL for 1986—2020 were collected, systematized and analysed, which showed an annual reduction in their number to 161.2 thousand people. The maximum number of the PACL was under monitoring in 1994—1996 (over 250 thousand people). The natural loss is the main reason for the reduction in the number. It was found that the cohort was formed during 1986—1990, when representatives of all regions of the country were involved in the liquidation of the consequences of the accident. It is characterised by gender asymmetry in favour of men and a certain disproportion in the age structure as a result of limited involvement in the activities of people under 25 years of age and over 60 years of age. It is shown that the age structure of the PACL differs from the country’s population of the corresponding age in the extremely high proportion of men; a disproportionately high proportion of men aged 35—39 (25.2 %) and women aged 60— 64 (20.5 %) in the first years after the accident; a significant proportion of people outside the working age range in recent years. The significant level of aging of the cohort (34.0 % of men and 51.5% of women have reached 65 years) requires maintaining the volume of medical care and increasing the need for medical and social services in the future. The study showed the limited possibility of using statistical sources of information from the Ministry of Health of Ukraine in scientific research on the number and structure of persons affected by the Chornobyl accident in the periods before 1993 and after 2019. It was found that as of today it is not possible to reliably assess the structure of the PACL due to the absence of an appropriate information base.