In this video I explain the unit called a "becquerel" which is used to measuring radioactive contamination in water, food, and other things. I also discuss the Japanese government's "safety" limits.
Having lived in Japan for several years and speaking to non-native English speakers so much, I really noticed in this video how slowly I've come to speak. I apologize and will try to return to "native" speed for future videos.
Japanese Science Ministry (MEXT) radioactive contamination in tap water information:
(Japanese)
http://www.mext.go.jp/a_menu/saigaijohou/syousai/1303956.htm
(English)
http://www.mext.go.jp/english/incident/1304083.htm
I have not had time to thoroughly investigate it, so I didn't report on it, however, going through the .pdf archives of radioactive iodine and cesium in tapster I was unable to find any reference of 210 becquerels/liter which was a high that the Tokyo tapster hit as reported by many local and foreign news sources when it happened. Here is one of many mainstream western media references to it (http://www.msnbc.msn.com/id/42225380/ns/world_news-asia_pacific/t/radiation-fea­rs-spread-tokyo-drinking-water/)
Japanese Health, Labor, and Welfare Ministry March 17, 2011 document detailing new safety limits of radioactive contamination in food and water:
http://www.mhlw.go.jp/stf/houdou/2r9852000001558e-img/2r9852000001559v.pdf
WHO, Germany, and U.S. radioactive iodine and cesium permitted levels information source:
http://simplyinfo.org/group/?p=1897
(This site has some good information, and some information that I would prefer to verify with a second source. If I were making a presentation beyond the scope of this informative video, I would seek an additional source to verify these figures, however time has not permitted me to do so right now.)
Plutonium damage to ape lung image credit:
photo by Robert Del Tredici from his book
"At Work In The Fields Of The Bomb"
(Harper and Row, 1987)