Global cancer risk from Fukushima is low, says WHO

BMJ 2013; 346 doi: (Published 01 March 2013) Cite this as: BMJ 2013;346:f1390
  1. Anne Gulland
  1. 1London

The risk to the world’s population of developing cancer after the explosions at the Fukushima nuclear plant in Japan is low, and no observable increase in cancer incidence above the baseline is expected, the World Health Organization has said.

WHO looked at the risks to the general population in the Fukushima area, the rest of Japan, and the rest of the world and the risks to the power plant and emergency workers who entered the plant after the March 2011 incident.1 The disaster occurred when a tsunami, triggered by a huge undersea earthquake, smashed into the plant, damaging four of six reactors.

In the two areas closest to the nuclear power reactor, however, the risks of developing certain cancers were higher than baseline. Experts in epidemiology, radiation risk modelling, dosimetry, and public health concluded that the risks were increased by around 4% for all solid cancers in females exposed as infants (from a baseline lifetime (up to age 89 years) risk of 29%), around 6% for breast cancer in females exposed as infants (from a baseline of 5.5%), and around 7% for leukaemia in males exposed as infants (from a baseline of 0.6%).

The report calculated that the increased risk for developing thyroid cancer among females exposed as infants was 70%. But the report said that because of the low lifetime risk of thyroid cancer (0.75%), even a large relative increase represented a small absolute increase in risk.

Of the emergency workers who entered the power plant immediately after the incident two thirds were estimated to have cancer risks in line with the general population, while a third were estimated to have a raised risk.

Maria Neira, WHO’s director for public health and environment, said that the report underlined “the need for long term health monitoring of those who are at high risk.”

The report said that the levels of radioactive material released into the atmosphere after the accident were too low to affect fetal development or outcomes of pregnancy. No increases in spontaneous abortion, miscarriage, congenital defects, or cognitive impairment are anticipated, it said.

Richard Wakeford, visiting professor at Dalton Nuclear Institute at the University of Manchester and a contributor to WHO’s report, said that the doses of radiation received by the surrounding population were small, even in the most exposed communities.

He added, “These doses produce an extra risk of cancer over a lifetime of about 1% at most, in addition to background lifetime cancer risks from all other causes of, on average, 40% for men and 29% for women. The extra cancer risk is much lower than this outside the most exposed communities. Radiation exposure from the Fukushima accident has had only a small impact on the overall health of the nearby population, and much less outside the most affected areas.”


Cite this as: BMJ 2013;346:f1390