Radiation is found everywhere in the environment, occurring both naturally and through human activity. Generally, it doesn’t represent a risk to health, unless it is found in elevated levels.
Dr. Trevor Stocki, a Research Scientist in Health Canada’s Radiation Protection Bureau, studies how radioactive material moves in the environment and how it could affect humans.
Under usual conditions, natural levels of radiation, such as those that come from the cosmos, are safe for humans and the environment. However, certain sources of radiation could have a bigger impact. This type of radioactivity is closely monitored by researchers such as Trevor.
“We monitor the environment all the time, but also specifically following nuclear incidents, such as those that occurred in Chernobyl or Fukushima, to examine the impact in Canada,” says Trevor. “In those cases, we were not able to find any significant impact on our water, our food sources or the air we breathe.”
In contrast, parts of Scandinavia were exposed to higher levels of radioactive contamination following the Chernobyl accident in 1986. Because of the meteorological conditions in Europe following the accident, there was significant fallout of radioactive particles in that part of the world. This was noticed from local atmospheric monitoring programs and then studied through the area’s reindeer population. Since lichen readily absorbs these particles in the air, reindeer who like to eat it during the winter can become contaminated.
Since the reindeer are domesticated and herded by the Sámi people of Scandinavia as a food source, researchers used specialized detectors to determine whether the reindeer had ingested too much radioactive material to be safe for human consumption. If they had, they would feed them clean food in the form of pellets or grass until the radioactivity level had fallen below guideline levels.
Over on Canadian soil, caribou and beluga are traditional food sources for many of the Inuit living in our Northern territories. It was important for Trevor to determine if these animals had also been exposed to elevated levels of radiation following international nuclear accidents. If there were substantially elevated levels of radioactivity in these animals, then for the people eating a large quantity of this type of meat, there could be an increased risk of getting cancer.
“In Canada, our levels have never been that high,” explains Trevor. “We had measured in the 1960s before stopping. These measurements were resumed following the Chernobyl accident, and we found that levels of radioactivity in caribou were even lower than before! This demonstrates that Chernobyl had a very limited impact in Canada.”
Impact on marine creatures
Inuit beluga and caribou hunters from the Northwest Territories and Yukon approached the Northern Contaminants Program because they were concerned about their food sources. The hunters were wondering whether the Fukushima accident could have had an impact on the beluga and caribou that they hunt for food.
Trevor and his colleagues measured the radioactivity found in a variety of meat samples, and were able to confirm that radioactivity was so minimal it was hard to detect. Researchers believe that because of the sheer size of the ocean and the existing currents, even if levels had not been low, it would have taken a long time for any radioactivity released from the Fukushima accident to reach the Canadian arctic and have an impact on marine wildlife. Similar results were found with respect to the caribou samples.
“I was happy to be able to reassure the community and to confirm that the levels were very low and didn’t pose a concern,” says Trevor.
Monitoring radiation levels from a variety of sources in various places is part of the important, ongoing work Health Canada carries out to ensure we remain safe.