Airborne gamma-ray emitters from Fukushima detected in New York State

An air-sampling network that operates continuously as part of New York State’s environmental surveillance program collected radionuclides emitted as a result of the Fukushima nuclear accident. Samples were collected, typically for 7 days each, by drawing ~600 m³ of air through a particulate-collecting filter followed in series by a canister containing activated charcoal. Additional air sampling was implemented at ~3-day intervals at two locations. Gamma-ray spectroscopy was used to confirm the detection of ¹³¹I, ¹³⁷Cs, ¹³⁴Cs, and ⁷Be in the particulate phase at all sites, with maximum concentrations near 1,260, 160, 160, and 5,200 μBq/m³, respectively. Gas-phase ¹³¹I, collected on activated charcoal, exhibited a maximum concentration of 3,400 μBq/m³ at the sites. Assessment of radionuclide levels in the air samples suggests that there were minimal health impacts from the airborne radionuclides as the activities contributed an insignificant amount to the annual human dose.