Unusual Nuclide Concentrations in Air after the 1986 Chernobyl Event

Abstract

Concentrations of 1.0-year 106 Ru, 2.8-year 125 Sb, 2.1-year 134 Cs, and 30-year 137 Cs were measured for a total of 39 air filter samples collected at Chico, California, and Reno, Nevada, during the month of May 1986. Radioactive debris in which 106 Ru, 125 Sb, and 134 Cs were enriched relative to 137 Cs reached the west coast of the United States during the first week of May 1986. The air mass that carried this debris seems to have circled the world and reached the west coast for the second time 3 weeks later during the last week of May 1986. Results obtained in this study indicate that the initial release of nuclear debris from the Chernobyl reactor took place in a manner similar to the atmospheric injection of radionuclides from a nuclear weapon's test.

Chernobyl Radioactivity in Surface Air over Washington D.C.

“…Levels of Chernobyl radioactivity in surface air at stations in the western United States have been reported previously [4,5,6]. In this study we present the results of the analysis of air filter samples collected for total suspended particulate matter in the Washington D.C. area during the months following the Chernobyl accident, and attempt to relate the longer-lived radionuclide concentrations to earlier observations.…”

“…This trend has some similarity to changes observed in stations in western North America. Surface air particulate samples taken in Chico, California, and Reno, Nevada [6] were reported to have very high initial 106 Ru/ 137 Cs values when slight radioactivity was first observed in early May. These were attributed to material ejected in the original explosion at the reactor.…”