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The ITU’s postponement of its Yokohama race led athletes to question its safety.
This article was originally published in the Jan/Feb 2012 issue of Inside Triathlon magazine.
On Sept. 19, 2011, the city of Yokohama was home to Japan’s first international sporting event since the earthquake, tsunami and ensuing Fukushima Daiichi nuclear disaster that occurred six months earlier. The Dextro Energy ITU World Championship Series Triathlon that took place on that day was originally scheduled to be the second stop on the WCS tour in 2011, on May 14, but the ITU postponed it due to concerns about radioactivity in Yokohama’s air and water.
Most athletes were grateful that safety was made a top priority, although there was some public whining about lost travel costs and WCS point reallocations.
But the ITU made the right call by postponing the race.
One of the reasons radiation is so insidious is that, unlike air pollution in Beijing, for example, it’s extrasensory. We can’t smell it, taste it, see it or feel it. Caution must be exercised.
What makes the radioactivity from nuclear disasters so dangerous to human and animal life is that it is ionizing, which means that the radioactive particles break chemical bonds and thereby cause cancers. By contrast, non-ionizing radiation from cell phones, microwaves and the like do not break chemical bonds.
Cancer risk from ionizing radiation is directly related to exposure, which is cumulative. In some cases exposure can be mitigated. For example, iodine-131, one of the radioactive isotopes that Fukushima emitted in large quantities, can cause thyroid cancer. But preemptive doses of regular iodine pills will bond with the thyroid and prevent the iodine isotopes from wreaking havoc.
Harmful effects of cesium-134 and cesium-137—the other primary isotopes released by the disaster—are harder to counteract, however, and exposure must be monitored. Exposure is measured in Sieverts and reported along metric scales. For example, there are 1 million micro-Sieverts in one Sievert and 1,000 milli-Sieverts in one Sievert.
How many Sieverts before you get cancer? It varies. Nuclear power plant workers in the U.S. are allowed a maximum annual exposure of 50 milli-Sieverts of radiation per year, the equivalent of 6 micro-Sieverts per hour for an entire year. Recommendations for the general public are much lower, around 1 or 2 milli-Sieverts per year, depending on conditions. Some scientists argue that 100 milli-Sieverts in a year is still a safe level. With the 1986 Chernobyl disaster in Ukraine being the only previous test-case for this kind of radiation exposure at this magnitude, threshold imprecision is understandable.
Fukushima is the modern world’s most devastating disaster to date in terms of cost, and it has been categorized a highest possible 7 on the International Nuclear Events Scale, alongside Chernobyl. In terms of exposure, it’s released about 10 percent of the ionizing radiation that Chernobyl did (which itself produced 400 times the ionizing radiation of Hiroshima, so still seriously lethal numbers).
How much of that radiation hit Yokohama? The city is 180 miles from Fukushima and well outside the 20K exclusion zone set up around the plant. But it’s still close enough to receive airborne radioactive particles as well as those released into the ocean when seawater was used to try to prevent a meltdown.
In March and April 2011, between the accident and the time when the ITU decided to postpone the race, isotope levels in Yokohama ranged between 0.1 and 0.4 micro-Sieverts per hour. This is well within a safe range. Yet in the midst of uncertainty, prolonged earthquake aftershocks and Japan’s overwhelming need to focus on disaster recovery (rather than athletics), the race’s postponement was clearly the safest choice.
In the week of the Sept. 19 triathlon, radiation readings did not detect any of the three radioactive isotopes in the waters of Yokohama’s swim venue. Good news indeed. Atmospheric radiation registered at levels between 0.06 and 0.11 micro-Sieverts per hour for each of the isotopes, even lower than the already safe levels of April.
Figuring that athletes spend about one week at a race venue, their total radiation exposure at the September event would have been around 30 to 55 micro-Sieverts, or about 1/1000th the annual dosage for nuclear industry professionals.
Considering that radiation exposure from flying at 35,000 feet is about 6 micro-Sieverts per hour, athletes probably absorbed more ionizing radiation from their flights to and from the race than they did at the race itself!
This is especially true if they ate only imported foods and specifically did not eat any Yokohama school lunches. (Statistics about food safety are difficult to pinpoint compared to the publicly available water and atmospheric readings, but there has been recent controversy about contaminated beef from Fukushima being fed to Yokohama’s schoolchildren.)
While athletes were at low risk of radiation sickness in Yokohama over the WCS race weekend, some countries still chose to withdraw their athletes from the original start list, including France and Germany, which chose to skip the race even though they’re still fighting for Olympic country spots. These decisions could have been precipitated by the World Health Organization’s hands-off approach to the disaster, saying people should travel at their own risk.
Despite the absence of some of the ITU’s brightest stars, the rescheduled race was a successful return to the international sporting stage. Athletes complimented the race and venue, especially in comparison to those of the WCS finale in Beijing the week prior. And in light of the World Triathlon Corporation’s recent eleventh-hour cancellation of a fourth 5i50 series race this year due to “low registration” numbers, that the ITU held a safe and successful Yokohama event in a country so recently disaster-struck is even more commendable.