The amount of radioactivity and radioactive substances in a person can be determined in a fifteen-minute measurement in STUK's mobile laboratory. Photo: STUK

Science and technology

In an ongoing effort to assess the radioactivity levels within the Finnish population, the Radiation and Nuclear Safety Authority (STUK) is set to conduct human radioactivity measurements in Rovaniemi. This initiative, which started in the 1960s, aims to understand the radioactive substances present in the human body and the amount of radiation emitted.

From April 8 to April 11, a specialized box truck stationed at the University of Lapland's Rovaniemi campus will serve as the measurement site.

Volunteers, including students and staff from the University of Lapland and the Lapland University of Applied Sciences, are slated to participate in this crucial research, with each session taking approximately fifteen minutes.

Similar assessments are also carried out in Helsinki and Tampere, forming a comprehensive study across key Finnish regions. Through these measurements, STUK seeks to calculate the radiation doses Finns are exposed to from radioactive substances within their bodies, distinguishing between naturally occurring and man-made sources.

The initial focus of such measurements targeted reindeer breeders in Northern Lapland, dating back to 1962. This group was particularly affected due to atmospheric nuclear weapons tests, which led to the deposition of radioactive materials through rain, especially in northern regions. Lichens, a primary food source for reindeer, absorbed this radioactivity, subsequently affecting the reindeer breeders due to their consumption of reindeer meat.

Since the cessation of nuclear weapons tests in the atmosphere in 1963, and the last known atmospheric nuclear explosion in 1980, the radioactivity levels in reindeer breeders have normalized to match those of the general population. Dietary diversification among the breeders has also played a role in this normalization.

Despite the historical presence of radioactive substances in Finnish nature from nuclear tests and the Chernobyl accident in 1986, STUK reassures that the current levels, particularly of caesium isotope 137, pose no significant health risk. These levels constitute less than one-thousandth of the total annual average radiation dose received from all sources, with the majority of radiation exposure to Finns coming from external sources like indoor radon gas, rather than internal radioactivity.