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Atmospherically-delivered 7Be, 210Po and 210Pb in bulk precipitation and air samples collected around the globe have provided valuable quantification on the rates of removal, as well as proportional mixing of attendant air masses; however, such studies during thunderstorm and typhoon events are limited. We report the first continuous time-series rainwater sampling and analysis of 7Be, 210Pb and 210Po from two typhoons and one thunderstorm during 2015 summer in Shanghai. The depositional fluxes within individual rain events of typhoons and thunderstorms varied by a factor of 10 for 7Be, 5.7 for 210Pb, 7.4 for 210Po, and 7.0 for 7Be/210Pb activity ratios (AR). Such large observed variations in the depositional fluxes of 7Be, 210Pb, 210Po and 7Be/210Pb activity ratios were attributed to air masses injected from surrounding high pressure system adjoining the typhoon to low pressure system within the typhoon. Based on 7Be/210Pb activity ratios, we estimated the variations in the fraction of maritime and continental air masses into the typhoon. Observed constancy in the 210Po/210Pb AR indicates that the residence times of air masses contributing to the typhoon during heavy rain are similar. From a synthesis of global fallout of 7Be and 210Pb during pulse events (precipitation≥50 mm from single rainout event), we quantify the importance of pulse events in the atmospheric fallout of these radionuclides. [ABSTRACT FROM AUTHOR]

This study monitored 210Pb levels of the atmospheric aerosol in Shanghai from January 2016 to February 2017. 210Pb levels were found to be low in non-haze weather events (1.46 ± 0.76 mBq/m3, n = 8) and high in moderate pollution weather events (2.34 ± 1.43 mBq/m3, n = 12). Similar to those of other East Asian regions, monthly averaged 210Pb concentration showed a U-shaped distribution pattern, indicating that the East Asian monsoon has an impact on atmospheric 210Pb. Particulate matters (PM) had a significant positive correlation with 210Pb, indicating that there might occur an intensified 210Pb scavenging processes. The linear correlation analysis revealed a clear link between 210Pb and some gaseous pollutants, strong positive correlation between CO and 210Pb (210Pb/CO, R = 0.63, P < 0.01), and weak correlation between 210Pb and O3 (R = − 0.35), NO2 (R = 0.42), and SO2 (R = 0.34). This phenomenon demonstrated that in haze weather, not only the general air pollutants concentrations have increased, but also the 210Pb concentration. Radiation dosimetry of daily inhalation of 210Pb through exposure to outdoor air is estimated to be relatively minor; children intake remains higher. [ABSTRACT FROM AUTHOR]

In complied data of atmospheric deposition of 210Pb and 7Be in the world, the data from China is of lack. In the present paper, atmospheric depositional fluxes of 7Be and 210Pb were simultaneously measured in semimonthly interval for 1 year (from November 2005 to October 2006) at Shanghai (31°13′39″N, 121°23′56″E), China, 50km from the coastal of East China Sea. The annual average flux of 210Pb and 7Be in 2006 is 4.79×102 and 2.07×103 Bqm−2 year−1, respectively. Compared with the published data, the highest flux of 210Pb in 2006 at Shanghai was clearly observed during studying periods. The possible reason for such high flux of 210Pb is discussed. Furthermore, deposition fluxes of both 210Pb and 7Be show varieties in seasons: highest flux of 210Pb in winter (November–August) and that of 7Be in spring (March–May). Moreover, the correlation between activity fluxes and precipitation are weak both for 7Be and 210Pb in whole of 2006; however, the high correlation are observed in autumn and spring for 7Be and that only in autumn for 210Pb. [Copyright &y& Elsevier]