Japan's Nuclear Crisis: Radiation and Health Risks

Americans continue to snap up the potassium iodide pills that can prevent radiation-related thyroid cancers. That's despite reassurances from public health officials that, for now, radioactive fallout from Japan's worsening nuclear crisis will have a negligible impact on U.S. shores.

Meanwhile, in Japan, the health risks of radiation from the crippled nuclear reactors at the Fukushima Daiichi nuclear plant are very serious, but still uncertain. The U.S. military is not allowing its forces within 50 miles of the Fukushima plant and is giving preventive potassium iodide pills to some of its pilots.

Here's more from a Reporting on Health look at recent coverage on the impacts of radiation on health as well as some reporting resources: 

As Shari Roan of the Los Angeles Times wrote:

Authorities have evacuated more than 170,000 people within 12 miles of the plant and have warned those within 20 miles to stay indoors and close off ventilation systems. They have also issued iodine tablets to those who have remained in the area and those at evacuation centers. At least 200 people have been exposed to radiation. Here's a look at the potential radiation exposures and effects on human health.

I especially like Roan's clear Q&A about the health risks from radiation, which points out the differences between ionizing radiation (dangerous, can cause cancer) and non-ionizing radiation (not dangerous, does not cause cancer). She also covers how the biological effects of ionizing radiation are measured (in sieverts), the difference between cesium-137 and iodine-131, and the long-term health consequences of the Chernobyl and Three Mile Island nuclear disasters.

Reuters offers a useful timeline of the unfolding nuclear crisis that includes measurements of microsieverts at the Fukushima plant.

Alice Park also provides a welcome Q&A about the health risks from radiation specifically in Japan, noting that Fukushima nuclear plant workers obviously are greater risk than others, but places that risk in context:

In the U.S., the Nuclear Regulatory Commission restricts workers to 50 millisieverts of radiation exposure per year. At the Fukushima plant's No. 2 reactor, radiation levels had hovered at about 73 microsieverts (0.073 millisieverts), before a blast sent the amount soaring to 11,900 microsieverts (11.9 millisieverts) three hours later.

Reporting Resources:

Guide to Ionizing Radiation Doses
U.S. Nuclear Regulatory Commission
U.S. Centers for Disease Control: Radiation Emergencies
Environmental Protection Agency: Radiation Protection
Radiation Effects Research Foundation
CDC: Acute Radiation Syndrome Fact Sheet

Photo credit: daveeza via Flickr