By Jay T. Cullen
Originally posted to Cancer Prevention Centre on Dec. 9, 2014
Public demand for information about the impact of the triple reactor meltdowns in March 2011 at the Fukushima-Daiichi nuclear power plant on the marine ecosystem and on the health of those residing on the Pacific coast of North America is considerable. After all, as a result of the devastating earthquake and tsunami, radioactive elements from the nuclear power plant, including but not limited to cesium, iodine, strontium, and plutonium, were released—and continue to be released—into the atmosphere and ocean. In the more than three years since the disaster, these elements have been distributed across the Pacific Ocean and around the globe.
Radioactive elements can pose significant direct hazards to human health–increasing risk for certain types of cancer, having negative impacts on ocean plants and animals, and posing indirect hazards (such as by consuming plants and animals that have been exposed to radiation). Over time, the hazards diminish as the elements decay. However, the half-life of the radioactive elements ranges from days to more than tens of thousands of years, depending on the element.
Models produced by oceanographers and atmospheric scientists disagree on the exact timing and concentrations of radioactive elements expected to arrive off the coast of British Columbia by way of ocean currents. In an effort to track the concentrations and what kind of risks they pose, I and my colleagues have established a new marine radioactivity monitoring network that is engaging scientists in Canada and the US, health experts, non-governmental organizations, and even citizen scientists along the British Columbia coast.
The InFORM Network—which stands for Integrated Fukushima Ocean Radionuclide Monitoring—includes about a dozen community sites along the British Columbia coast where volunteer citizen scientists are collecting water and seafood samples monthly or bimonthly for analysis. Those samples are supplementing measurements already being taken offshore by the Department of Fisheries and Oceans and an existing citizen scientist network along the Pacific Coast. In addition, we are collecting salmon to determine the extent of contamination accumulating in the fish during their time migrating and feeding in waters around Japan. The InFORM Network is funded by the Marine Environmental Observation Prediction and Response (MEOPAR) Network, a Canadian Centre for Excellence established by the Federal Government in 2012.
Scientific studies that have been completed so far, in conjunction with results from the InFORM Network and what we know about exposure levels, indicate that radioactivity from the Fukushima-Daiichi disaster poses no danger and is not expected to affect the health of those on the Pacific Coast of North America. In fact, the radioisotopes owing to human activities in seawater and marine organisms largely reflect legacy sources from atmospheric nuclear weapons testing in the 20th century.
The most recent results of Kelp Watch 2014, a program dedicated to monitoring for the presence of Fukushima sourced radionuclides off the Pacific Coast, show that no radioactive isotopes from Fukushima were detected in kelp growing at sampling sites spread across the eastern Pacific Coast. Recent tests for plutonium in the seawater and marine sediments off the coast from Fukushima showed negligible levels owing to the disaster itself against the background contamination from weapons testing. In another recently published study, a three-dimensional model for tracking the dispersion and fate of strontium in the waters and biota of the northwest Pacific Ocean was developed and showed that strontium levels are well below the maximum dose limits thought to be detrimental to public health. Furthermore, measurements made various species of fish caught off the west coast by Health Canada (data available for download here) have not detected isotopes of cesium from Fukushima as of August 2014. More than 100 sockeye salmon and steelhead from the 2014 summer and fall returns to BC rivers are currently being analysed as part of the InFORM project with first results released in December 2014.
While so far the measured levels are not a point of concern, we want to continue to monitor for Fukushima-derived contamination because even three years later these isotopes are still being released. Anyone who is interested in becoming a citizen scientist and contributing to the efforts of the InFORM Network is encouraged to contact us.