Slight increase in cancer cases since the Chernobyl accident
The nuclear accident in Chernobyl in 1986 led to the spread of radioactivity across Sweden and Europe. In a long-term study, now published in Environmental Epidemiology, researchers use new, more specific calculation methods to show links between radiation dose and certain types of cancer.
Martin Tondel, researcher in occupational and environmental medicine.
The current study is a long-term follow-up covering all the inhabitants - 2.2 million - living in nine counties (Norrbotten, Dalarna, Södermanland, Jämtland, Västmanland, Gävleborg, Västerbotten, Uppsala and Västernorrland) in 1986. In these counties there are people with different levels of radiation dose from the Chernobyl fallout caused both by ingestion of contaminated food and from the landfill, who have been followed in the national cancer registry until 31 December 2020.
Previous monitoring in Sweden, most recently in 2010, has shown a slight increase in all cancers combined, linked to the landfill.
"The big difference from these studies is that we have now developed and used a dose calculation programme to calculate the radiation doses to the body's various organs from soil and food," says Martin Tondel, researcher in occupational and environmental medicine at the Department of Medical Sciences, Uppsala University and Uppsala University Hospital.
In the study, the researchers compared the estimated radiation doses from soil and different foods to different body organs with the incidence of different cancers. They have also adjusted for potentially influential factors such as underlying cancer prevalence in the counties before the Chernobyl accident, living in urban/rural areas, level of education, age and gender.
The results show a slight increase in colon, pancreatic and gastric cancer in men and a slight increase in lymph node cancer in women. However, the risk increases are small and do not affect the assessment of risk at the individual level, the researchers say, stressing that it is important to interpret epidemiological results with caution.
"Demonstrated associations do not mean that we can say with certainty that radiation is also the cause. But studies after nuclear accidents are very important for gaining more knowledge about radiation and cancer and for developing research methods. For example, we have identified that the lifestyle of a hunter may have played a role in our results, which means that we will be able to reach even more reliable conclusions in future studies," says Martin Tondel.
Publication:
Tondel, Martin et al.; Dose–response analysis of protracted absorbed organ dose and site-specific cancer incidence in Sweden after the Chernobyl nuclear power plant accident. Environmental Epidemiology 7(6):p e277, December 2023. | DOI: 10.1097/EE9.0000000000000277, https://journals.lww.com/environepidem/fulltext/2023/12000/dose_response_analysis_of_protracted_absorbed.6.aspx
For more information:
Martin Tondel, researcher in occupational and environmental medicine, Department of Medical Sciences, Uppsala University, and Uppsala University Hospital, e-mail: martin.tondel@medsci.uu.se, telephone: 018-611 36 57, 072-450 18 57.
The study is a collaboration between Uppsala University, Uppsala University Hospital, Lund University and the University of Gothenburg, and has been financed with state ALF funds.
https://www.vr.se/uppdrag/klinisk-forskning/klinisk-forskning-i-alf-regionerna.html