Award: OCE-1136693

The triple disaster of the March 11, 2011, earthquake, tsunami, and subsequent radiation releases at Fukushima Dai-ichi were unprecedented events for the oceans, including being the largest accidental release of man-made radionuclides to the oceans in history. This study was designed to establish a baseline for the levels of key radionuclide contaminants in the Atlantic and Pacific oceans, and to collect aerosol samples in Woods Hole Massachusetts. For the ocean baseline, we had several groups collect seawater samples (20 Liters) in March and April for analysis of cesium isotopes. From the ratio of cesium-134 to cesium-137, we can uniquely determine if the contamination came from Fukushima or other sources (such as prior fallout from atmospheric nuclear testing in the 1960Æs). Samples were collected (East to West) from Bermuda, Woods Hole, Santa Barbara, Hawaii, Mid-Way and Guam. Analysis thus far show only slight evidence of Fukushima cesium in samples collected off Santa Barbara in March, 2011 (analyses of Hawaii, Guam and Mid-Way are being conducted under separate funding by H. Dulaiova, U. Hawaii). This fits with our understanding of the release of these contaminants, which was low in the "far field" as concentrations in the atmosphere- as measured with the arrival of air born Fukushima cesium 134, cesium 137 and iodine-131 after March 21 in Woods Hole- were too low to cause wide spread ocean increases in Fukushima contaminants. This project also led to development of a new method for measuring cesium isotopes in the ocean, which allowed for a more complete sampling of cesium in the ocean in the "near field" during a research cruise off Japan in June 2011 (the cruise was funded by the Gordon and Betty Moore Foundation). During that cruise, we detected Fukushima radionuclides, in particular cesium isotopes, in waters 20-400 miles off shore. We addressed risks to public health and marine biota by showing that while Cs isotopes were elevated 10-1000 times over prior levels in waters off Japan, radiation risks due to these radionuclides are below those generally considered harmful to marine animals and human consumers, and even below those from naturally occurring radionuclides. Data are available on an open data management web site: http://osprey.bco-dmo.org/project.cfm?flag=viewd&id=186&sortby=project . Results from these studies have also been widely shared with public audiences and the media. A selection of the more than 50 interviews and media reports can be found at: http://www.whoi.edu/page.do?pid=69136 . Also listed below are several articles written by our group in response to the public interest in marine radioactivity in general, and Fukushima contaminants in particular. Buesseler, K. O. March 2012 What the Fukushima accident did to the ocean. CNN op-ed Fisher, N. S. and Buesseler, K. O. (2011). Tracking Fukushima radionuclides: A research cruise in Japanese waters. Bulletin of the Atomic Scientists, July 19. Japan 2011. WHOI web site with links, articles, video. Buesseler, Ken (April 26, 2011). Japan's irradiated waters: How worried should we be? CNN Opinion on-line. Last Modified: 05/08/2012 Submitted by: Ken O Buesseler