Elevated radioxenon detected remotely following the Fukushima nuclear accident

We report on the first measurements of short-lived gaseous fission products detected outside of Japan following the Fukushima nuclear releases, which occurred after a 9.0 magnitude earthquake and tsunami on March 11, 2011. The measurements were conducted at the Pacific Northwest National Laboratory (PNNL), (46 degrees 16'47 '' N, 119 degrees 16'53 '' W) located more than 7000 km from the emission point in Fukushima Japan (37 degrees 25'17 '' N, 141 degrees 1'57 '' E). First detections of Xe-133 were made starting early March 16, only four days following the earthquake. Maximum concentrations of Xe-133 were in excess of 40 Bq/m(3), which is more than x40,000 the average concentration of this isotope is this part of the United States. (C) 2011 Published by Elsevier Ltd.