The conflicted World Health Organization (WHO) - which cannot pronounce on things nuclear without ceding to the nuclear-promoting International Atomic Energy Agency (IAEA) - predictably downplayed the likely health impacts resulting from the Fukusima nuclear disaster. The Japanese government went even further, suggesting the WHO over-stated the likely impacts. Fundamentally, the WHO found, after a two-year study, that "the risk for certain types of cancers had increased slightly among children exposed to the highest doses of radioactivity, but that there would most likely be no observable increase in cancer rates in the wider Japanese population." However, the agency was at least forced to admit that "their assessment was based on limited scientific knowledge; much of the scientific data on health effects from radiation is based on acute exposures like those that followed the bombing of Hiroshima and Nagasaki and not chronic, low-level exposure." Almost all the health effects from Fukushima will result from prolonged exposure to so-called "low levels" of radiation. Read more.
(To understand the limitations imposed on the WHO by the IAEA, read here.)