Prospective cohort study of residents near the Semipalatinsk nuclear test site - feasibility

The former Soviet Union's Semipalatinsk nuclear test site (STS) is located in the present East-Kazakhstan oblast of Kazakhstan, an area that previously belonged to the Semipalatinskii oblast region. The test site is named after the city of Semipalatinsk (in Kazakh: Semey) situated approximately 150 km east of it. The test site covers an area of 18,500 km² or 7,143 square-miles. The STS was the major site for nuclear weapons testing by the former USSR, and it was the place where the former Soviet Union conducted their first nuclear test on August 29, 1949. During the following 40 years, 456 nuclear explosions were carried out between 1949 and 1962, including 111 atmospheric events (86 events in air and 25 surface events) between 1949 and 1962. There are reports on epidemiological studies on health effects of exposures to fallout from Soviet nuclear weapons testing for the residents living near by Semipalatinsk Nuclear Test Site (SNTS) in Kazakhstan conducted in two cohorts collected separately by the Kazakh Scientific Institute for Radiation Medicine and Ecology (KSIRME) and National Nuclear Center (NNC) with different funding resources and contradicting results. However, both cohorts have high potential to address the question of the effects on human health of low and moderate levels of radiation both as a result of external exposure in the early years of activities at SNTS and following long time intake of radionuclides from the fallout. The SEMI-NUC project on health effects from radiation exposure of people living near SNTS in Kazakhstan has started in May 2013 to assess the feasibility of establishing a long term prospective cohort to study health effects considering both "Historical cohort" (HC) and "New cohort" (NC). NRPA is involved all Work Packages (WP) with main involvement into WP3 (Task leader-Tamara Zhunussova), WP5-6 (Alicja Jaworska) The WP3 is on "Identification of sources and mechanisms in determination of health effects for prospective studies among the residents living near the Semipalatinsk Nuclear Test Site". Since the start of the SEMINUC project we had 3 meetings/workshops. 1. Kick off meeting (Lyon, France)-May 6, 2013 with the main objective to investigate the feasibility of setting up a unified cohort of residents around the Semipalatinsk Nuclear Test Site (SNTS) which will include preparation for prospective follow-up of populations exposed to fall-out from STNS for various long term health effects and establishing an international multidisciplinary research team, if the feasibility is demonstrated. 2. Second meeting (Semipalatinsk, Kazakhstan)-September 17-20. Participants from KSIRME have presented the construction of the cohort of the population exposed to fall-out which is a challenge and requires verification using several available sources. 268,763 persons registered now: 95,608 of them died; 19,661 - are members of the historical cohort. Afterwards, all participants took a tour of the facilities. This included viewing documentation of patient records in the archives that were extracted for the establishment of the historical cohort. In addition, participants visited the facilities in which biological samples are stored and analyzed. WBC, DNA samples from families (up to 3 generations) are stored here. Sampling is done at the time of medical check-ups. 3. Third meeting (midterm) was held in Munich, Germany with the aim to overview the status of the project. WP leaders presented the work done during the given period. NRPA was presented on this meeting by Tamara Zhunussova (leader of WP3) and Alicja Jaworska (participant in WP5 and WP6) So far the results are satisfactory except for WP5-6 where some delays have occurred. Tamara Zhunussova had presented results of WP3: For the WP3 "Identification of sources and mechanisms in determination of health effects for prospective studies among the residents living near the Semipalatinsk Nuclear Test Site" the progress has been demonstrated and the preliminary results as following: For identification of mechanisms and sources for case ascertainment (both cancer and non-cancer diseases) the following sources of information have been used: household book, birth certificate, death certificate issued by ZAGS (based on the post-mortem or forensic autopsy protocol), reason of death, marriage certificate, interviews, registration card with names, date of birth, nationality, residential history including the period and place of residence in the contaminated areas, vital status, education, occupation, and so called "polygon license" and many other detailed information from the Diagnostic Center in Semipalatinsk and medical hospital record from KSIRME.

The health effects of exposures to fallout from Soviet nuclear weapons testing for the residents living near by the Semipalatinsk nuclear test site in Kazakhstan are not well investigated. There are reports with contradicting results coming from the studi es conducted on two independent cohorts: "historical" and "new". Both use different control groups and dosimetric methods. The two cohorts have a high probability of including the same individuals. There is a need to investigate possibilities to merge the m in order to avoid duplication of efforts and resources for future studies of the health effects in these populations. The main objectives of our feasibility study include: developing and testing mechanisms for identifying members in the two cohorts; ide ntification and testing of data linkage mechanisms; characterization and validation of dose assessment methods; determination of the outcomes to be studied; identification of case ascertainment mechanisms and sources, depending on the outcome; investigate the feasibility to collect data on confounding factors; setting up and testing procedures for follow-up; development of a proposal for a full epidemiological study; setting up mechanisms for collaboration and coordination of future activities. The proj ect will bring together scientists from Europe, Kazakhstan and Japan with the aim of conducting a feasibility to set up a unique cohort to address the dose-effect relationship for both cancer and non-cancer effects from low to moderate chronic doses (exte rnal and internal). Other populations exposed to low to moderate dose radiation like in Fukushima or elsewhere can benefit from the outcomes of studying the unique Semipalatinsk cohort and the results will contribute to a better understanding and quantifi cation of radiation risks for low to moderate chronic doses. The proposed project is in line with the Strategic Research Agenda of MELODI.