A Study on Radon Absorption Efficiencies of Edible Oils Produced in India

Abstract

A study on absorption of radon by different edible oils of plant origins produced and used in India was conducted in order to identify efficient radon-absorbing oils. A comparative study of radon absorption by edible oils of India with that of olive oil, which is known as a good absorber of radon, was also carried out. The study was performed by bubbling known concentrations of radon through the oil contained in a bottle and then evaluating the bubbled oil by gamma-ray spectrometry using an HPGe detector. The results show that oils such as coconut oil, gingelly oil (till oil), ground nut oil, mustard oil, sunflower oil, and saffola kardi oil are also good absorbers for radon, and among them coconut oil and gingelly oils are better absorbers than olive oil. The Henry's equilibrium constant (or the concentration factor), an indicator for the solubility of gas in liquids, was also measured for different types of oil by saturating a known volume of the oil with radon. The Henry's equilibrium constant varied in the range 7.32-8.22 for the Indian vegetable oils, and for olive oil it was found to be 7.88. The details of the experimental technique employed and results obtained are presented and discussed in this paper.

A periodic pumping technique of soil gas for 222Rn stabilization in large calibration chambers: part 2—theoretical formulation and experimental validation

“…Advantages of soil gas 222 Rn over the conventional sources are instantaneous natural availability, zero regeneration time required, zero cost, and excellent source stability. These features of soil gas 222 Rn are well described in the previous publications 10,14,18 . Through the semi-dynamic mode of operation, it was shown that the 222 Rn concentration could be maintained with a deviation of ± 20% from the desired value using soil gas.…”

“…In our previous publications, we demonstrated the harvesting of soil gas as a highly efficient secondary source of 222 Rn for calibration experiments 13 – 16 as well as a substitute for 226 Ra source in research studies 17 , 18 . Advantages of soil gas 222 Rn over the conventional sources are instantaneous natural availability, zero regeneration time required, zero cost, and excellent source stability.…”

Development of a “222Rn incremented method” for the rapid determination of air exchange rate using soil gas

“…The 222 Rn detection range of the scintillation cell-based monitor was 8 Bq m −3 to 50 MBq m −3 , while the ionization chamber-based monitor was 2 Bq m −3 to 20 MBq m −3 . The detailed specification of these instruments was published previously ( Al-Azmi and Karunakara, 2007 ; Karunakara and Al-Azmi, 2010 ; Karunakara et al, 2015 ; Sudeep et al, 2017 ; Sahoo et al, 2017 ; Shetty et al, 2019 ).…”

An innovative technique of harvesting soil gas as a highly efficient source of 222Rn for calibration applications in a walk-in type chamber: part-1

“…The detection range of ionization chamber based reference monitor is 2 Bq m -3 to 2000 kBq m -3 , while that of scintillation cell-based monitor is 8 Bq m -3 to 50,000 kBq m -3 . The details of these instruments were published earlier 1 , 14 , 16 – 19 . The primary calibration of the ionization chamber-based monitors was initially carried out under a Physikalisch Technische Bundesanstalt (PTB) reference atmosphere and that of scintillation cell-based monitors at BARC, Mumbai.…”

“…Soil gas was also used as a source of high 222 Rn and 220 Rn concentrations in studies aimed at developing techniques for mitigation of these gases in workplaces 16 – 18 . It was also used as a source of 222 Rn for studying the 222 Rn absorption capacity of edible oils 19 . But its use as a source for 222 Rn in calibration and exposure experiments in walk-in kind of chambers has not been reported earlier, and the present work is first of its kind.…”