The temporal variations of 7Be, 210Pb and 210Po in air in England

We have conducted measurements of naturally occurring radionuclides 7Be, 210Pb and 210Po in air at ground level at Chilton, Oxfordshire, England. The sampling and analysis regime for the latter two isotopes has been optimised to minimise uncertainties in measurement due to decay of 210Po and in-growth of 210Pb during the sampling and analysis period. Analysis times were reduced by using Cerenkov counting to assay the 210Bi daughter of 210Pb. Monthly data collected over a four-year period are presented and discussed. 7Be activity concentrations appear to peak in spring. 210Pb activity concentrations also follow a seasonal trend reflecting different 222Rn emanation rates from soil during winter and summer. Data for 210Po show no such trend.