Radioactive isotopes in atmospheric aerosols over Russia and the Sea of Japan following nuclear accident at Fukushima Nr. 1 Daiichi Nuclear Power Station in March 2011

Abstract

Artificial radionuclides, such as iodine-131 ((131)I), cesium-134 ((134)Cs), and cesium-137 ((137)Cs), as well as natural isotopes of beryllium-7 ((7)Be) and potassium-40 ((40)K) have been registered in atmospheric aerosols over Vladivostok selected from 11 March to 17 June 2011. Additionally, (134)Cs and (137)Cs were detected in atmospheric aerosols over Tomsk selected from 16 March to 17 June 2011. Artificial radionuclides were also discovered in atmospheric wet depositions sampled in Vladivostok from 3 to 17 May 2011. Moreover, these radionuclides have been registered in atmospheric aerosols over the sea surface of the Sea of Japan selected from 3 to 31 May 2011 during an expedition of the "Nadezhda" sailing ship. From 18 March to 15 April, an increase in concentrations of atmospheric aerosols over Vladivostok from 108.8 to 321.5 μg/m(3) has been registered. It was accompanied by increased activity concentrations of (134)Cs, (137)Cs, and the (131)I. During the period from 18 March to 15 April, activity concentrations of (137)Cs and (134)Cs in atmospheric aerosols increased 100 times compared with the minimum detectable concentration (MDC) level and peaked in the weekly sample gathered from 8 to 15 April (145.0 and 105.3 μBq/m(3), respectively). Variability of concentrations of natural isotopes of (7)Be and (40)K was not greater than 1 order of magnitude throughout the sampling period. Maximal values of (137)Cs and (134)Cs concentrations (1,281.5 ± 141 and 384.4 ± 42.3 μBq/m(3), respectively) in Tomsk were reached in samples taken from 1 to 2 April. For the atmospheric aerosol samples from the Sea of Japan, the largest concentration of (131)I (392.3 ± 215.7 μBq/m(3)) was detected from 13 to 19 May, while all other samples had much lower concentration values. Synoptic analysis of back trajectories movement of air masses showed that the radioactive cloud came to Vladivostok from the regions of Siberia and northeastern part of China. Synoptic analysis for Tomsk showed that during the period of maximal activity concentrations (1-9 April), air masses were arriving from the European part of Russia and north of Kazakhstan.

Szennyezőanyagok légköri koncentrációját előrejelző modellrendszer fejlesztése és alkalmazása

“…Ennek során bizonyos időszakokban, elsősorban március 17-20. között a radioizotópok nem a Csendes-óceán felé, hanem délnyugati irányba terjedtek, ezért Délkelet-Ázsiában már március 23-27. között történtek észlelések (Huh et al, 2012;Long et al, 2012). A Japánhoz közel eső Kelet-Oroszországban, Koreában, Kínában és Tajvanon a kelet felől érkező közvetlen szennyezés, valamint a nyugatról érkező hemiszférikus transzport egyaránt kimutatható volt (Hong et al, 2012;Huh et al, 2012;Neroda et al, 2014;Wan et al, 2014).…”

“…Az elmúlt években számos Lagrange-i modellezésen alapuló eredmény született a fukushimai kibocsátás vizsgálatára, amelyek operatív alkalmazását a WMO koordinálta . Gyakori alkalmazás volt a forrásbecslés és egy adott helyen detektált radioizotóp érkezési irányának meghatározása (Stohl et al, 2012;Terada et al, 2012;Neroda et al, 2014;Wan et al, 2014). Vizsgálták a terjedési modell eredményeinek érzékenységét a bemenő meteorológiai adatokra (Arnold et al, 2015) és a nedves ülepedés parametrizációjának beállításaira (Leadbetter et al, 2015).…”

Design of a mono-disperse aerosol generator for efficiency testing of HEPA filter

“…The radioactive aerosols formed by suspension of radioactive materials in the air are one of the most important pollutant sources in the workplace environment, such as nuclear technology applications, nuclear facilities, and nuclear and radiation terrorist incidents [7,15,18,19]. The radioactive aerosols can invade into the human body through the human breathing, skin absorption and other means, which is one of the main ways to cause the internal irradiation hazards in the human body, [1,9,12,13]. The high efficiency particle air (HEPA) filter is usually used in nuclear facility air purification system to remove the radioactive aerosol.…”