Abstract: ²¹⁰Pb and ²¹⁰Po in atmosphere are mainly from the decay of radon in surface soil on the earth, which are the last two long-lived daughter radionuclides in uranium decay chain. A method for analysis of ²¹⁰Pb using ²⁰⁶Pb as carrier following the sample separation by ion exchange was developed to determine the activity concentrations of ²¹⁰Pb and ²¹⁰Po in atmosphere; and a method for the analysis of ²¹⁰Po employing ²⁰⁹Po as tracer and counted by α spectrometer was developed. The ²¹⁰Pb and ²¹⁰Po concentrations in atmospheric aerosol in Hangzhou were carried out. Continuous monitoring results in 2012 showed the average ²¹⁰Pb concentration was (1.31±0.69) mBq/m³, ranging from 0.12 to 2.74 mBq/m³. The average ²¹⁰Po concentration was (0.29±0.18) mBq/m³,ranging from 0.06 to 0.89 mBq/m³. The ²¹⁰Pb and ²¹⁰Po concentrations in Hangzhou were comparable with other cities in China, while one order of magnitude higher than the American and European cities. Public committed effective dose by inhalation from atmospheric ²¹⁰Pb and ²¹⁰Po was 1.53 to 13.78 μSv/y, with an average value of 7.00 μSv/y.

Key words: ²¹⁰Pb, ²¹⁰Po, activity concentration, public dose