A guide to natural and man-made sources of radiation in the environment post-Fukushima.(View the Chinese translation)
Thorium-234 is used as a natural radioactive tracer of biological processes in the ocean.
FAQ about the release of radiation from Fukushima to the Pacific.
Overview of events leading up to and subsequent to the release of radiation from Fukushima.
Special issue of Oceanus magazine highlighting what is known about the release of radiation from Fukushima and its impact on the ocean and human health.
Washington State Department of Health
Chart of dose, exposure time, and source from Information is Beautiful
U.S. Environmental Protection Agency web site devoted to a range of topics on radiation safety.