Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2017:2017:1930787.
doi: 10.1155/2017/1930787. Epub 2017 May 22.

Inhalation Dose and Source Term Studies in a Tribal Area of Wayanad, Kerala, India

Reshma Bhaskaran  1   2 , Ravikumar C Damodaran  2 , Visnuprasad Ashok Kumar  3 , Jojo Panakal John  3 , Danalakshmi Bangaru  4 , Chitra Natarajan  4 , Bala Sundar Sathiamurthy  4 , Jose Mundiyanikal Thomas  4 , Rosaline Mishra  5
Affiliations

Inhalation Dose and Source Term Studies in a Tribal Area of Wayanad, Kerala, India

Reshma Bhaskaran et al. J Environ Public Health. 2017.

Abstract

Among radiation exposure pathways to human beings, inhalation dose is the most prominent one. Radon, thoron, and their progeny contribute more than 50 per cent to the annual effective dose due to natural radioactivity. South west coast of India is classified as a High Natural Background Radioactivity Area and large scale data on natural radioactivity and dosimetry are available from these coastal regions including the Neendakara-Chavara belt in the south of Kerala. However, similar studies and reports from the northern part of Kerala are scarce. The present study involves the data collection and analysis of radon, thoron, and progeny concentration in the Wayanad district of Kerala. The radon concentration was found to be within a range of 12-378 Bq/m3. The thoron concentration varied from 15 to 621 Bq/m3. Progeny concentration of radon and thoron and the diurnal variation of radon were also studied. In order to assess source term, wall and floor exhalation studies have been done for the houses showing elevated concentration of radon and thoron. The average values of radon, thoron, and their progeny are found to be above the Indian average as well as the average values reported from the High Natural Background Radioactivity Areas of Kerala. Exhalation studies of the soil samples collected from the vicinity of the houses show that radon mass exhalation rate varied from below detectable limit (BDL) to a maximum of 80 mBq/kg/h. The thoron surface exhalation rate ranged from BDL to 17470 Bq/m2/h.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Distribution of radon concentration in phase 1 study.
Figure 2
Figure 2
Distribution of thoron concentration in phase 1 study.
Figure 3
Figure 3
Q-Q plot for radon concentration.
Figure 4
Figure 4
Q-Q plot for thoron concentration.
Figure 5
Figure 5
Inhalation dose to the residents of Bathery, Wayanad, Kerala.
Figure 6
Figure 6
Diurnal variation of radon in one house for 5 days.
Figure 7
Figure 7
Diurnal variation of radon in the house showing maximum radon concentration.
Figure 8
Figure 8
232Th versus thoron exhalation rate in soil.
Figure 9
Figure 9
Variation of indoor radon and thoron concentration with construction material.
Figure 10
Figure 10
Distribution of exposure to total radon concentration (radon concentration + equivalent radon concentration for thoron concentration).
See this image and copyright information in PMC

References

    1. UNSCEAR. Sources and effects of ionising radiation.united nations scientific committee on effect of atomic radiation. Report to the General Assembly. 2000
    1. SENES Consultants Limited for Canadian Nuclear Safety Commission, “Estimation of the Range of Radiation Dose for a Radon Progeny Working Level Due to Physical Parameters,” 2013.
    1. Wiegand J., Feige S. Thoron: ignored and underestimated in the big shadow of radon—an example from China. Geofisica Internacional. 2002;41(3):261–264.
    1. Shang B., Chen B., Gao Y., Wang Y., Cui H., Li Z. Thoron levels in traditional Chinese residential dwellings. Radiation and Environmental Biophysics. 2005;44(3):193–199. doi: 10.1007/s00411-005-0020-5. - DOI - PubMed
    1. Ramola R. C., Gusain G. S., Rautela B. S., et al. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha, India. Radiation Protection Dosimetry. 2012;152(1–3):62–65. doi: 10.1093/rpd/ncs188. - DOI - PubMed

LinkOut - more resources