MAP: The Troubling Spread of Radiation in Japan

Fight disinformation: Sign up for the free Mother Jones Daily newsletter and follow the news that matters.


A map of radiation levels in Japan released by the US Department of Energy on Tuesday evening indicates that potentially dangerous levels of radioactive contamination have spread beyond the 13-mile evacuation zone surrounding the Fukushima Daiichi nuclear plant. The data is sure to further undermine confidence in Japan’s response to the disaster. US authorities have recommended that Americans stay at least 50 miles from the Fukushima Daiichi plant. Here’s the map, which was generated from the DOE’s Aerial Monitoring System and ground sensors:

Spread of radiation for the Fukushima Daiichi nuclear plantSpread of radiation from the Fukushima Daiichi nuclear plant

To put these numbers in context, a typical chest X-ray produces 10 mRem. US EPA guidelines require government intervention if the public is exposed to more than 1000 mRem over four days. People near Fukushima could be exposed to that amount of radiation at least every 3.3 days in the red zone and anywhere from there to every 19 days in the orange zone above. Of course, it’s unclear from the chart to what degree radiation levels in the area fluctuate over time. “Measurements show an area of greater radiation extending northwest from the accident,” a DOE backgrounder notes, adding with dry understatement: “This area may be of interest to public safety officials and responders.”

A BETTER WAY TO DO THIS?

We have an ambitious $350,000 online fundraising goal this month and we can't afford to come up short. But when a reader recently asked how being a nonprofit makes Mother Jones different from other news organizations, we realized we needed to lay this out better: Because "in absolutely every way" is essentially the answer.

So we tried to explain why your year-end donations are so essential, and we'd like your help refining our pitch about what make Mother Jones valuable and worth reading to you.

We'd also like your support of our journalism with a year-end donation if you can right now—all online gifts will be doubled until we hit our $350,000 goal thanks to an incredibly generous donor's matching gift pledge.

payment methods

A BETTER WAY TO DO THIS?

We have an ambitious $350,000 online fundraising goal this month and we can't afford to come up short. But when a reader recently asked how being a nonprofit makes Mother Jones different from other news organizations, we realized we needed to lay this out better: Because "in absolutely every way" is essentially the answer.

So we tried to explain why your year-end donations are so essential, and we'd like your help refining our pitch about what make Mother Jones valuable and worth reading to you.

We'd also like your support of our journalism with a year-end donation if you can right now—all online gifts will be doubled until we hit our $350,000 goal thanks to an incredibly generous donor's matching gift pledge.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate