Image credit: Sakucae, Flickr

Over 110,000 people were moved from their homes following the Fukushima nuclear disaster in Japan in March 2011. Another 50,000 left of their own will, and 85,000 had still not returned four-and-a-half years later.

While this might seem like an obvious way of keeping people safe, my colleagues and I have just completed research that shows this kind of mass evacuation is unnecessary, and can even do more harm than good. We calculated that the Fukushima evacuation extended the population’s average life expectancy by less than three months.

To do this, we had to estimate how such a nuclear meltdown could affect the average remaining life expectancy of a population from the date of the event. The radiation would cause some people to get cancer and so die younger than they otherwise would have (other health effects are very unlikely because the radiation exposure is so limited). This brings down the average life expectancy of the whole group.

But the average radiation cancer victim will still live into their 60s or 70s. The loss of life expectancy from a radiation cancer will always be less than from an immediately fatal accident such as a train or car crash. These victims have their lives cut short by an average of 40 years, double the 20 years that the average sufferer of cancer caused by radiation exposure. So if you could choose your way of dying from the two, radiation exposure and cancer would on average leave you with a much longer lifespan. Continue reading →