Ingestion of Polonium (²¹⁰Po) via dietary sources in high background radiation areas of south India

Abstract

Purpose: To study the distribution of Polonium (²¹⁰Po) activity in dietary sources in the high background radiation zone of Puttetti in southern Tamil Nadu.

Materials and methods: ²¹⁰Po was analyzed in the food materials consumed by the male and female individual representatives living in the high background areas by 24-h Duplicate Diet Study (DDS) and Market Basket Study (MBS). The MBS was performed by collecting the food samples such as, cereals, fruits, leafy vegetables, roots and tubers, other vegetables, fish, meat and milk grown in the high background radiation zone of southern Tamil Nadu as a part of baseline study in this region. The DDS was done by collecting the food materials consumed including the beverages in 24 h from different age groups of male and female individuals living in the village of Puttetti. The intake and ingestion dose of the radionuclide ²¹⁰Po was estimated.

Results: The average concentration of ²¹⁰Po in DDS (n = 33) was found to be 74 mBq.kg^{− 1} of fresh weight. The MBS was collected based on food consumption representing more than 85–95% of annual supply, and were divided into eight food groups. The average concentration of ²¹⁰Po in the eight food groups namely leafy vegetables was 2176 mBq.kg^{− 1} (n = 3), vegetables 55 mBq.kg^{− 1} (n = 10), roots and tubers 251 mBq.kg^{− 1} (n = 4), fruits 65 mBq.kg^{− 1} (n = 5), fish 345 mBq.kg^{− 1} (n = 2), meat food 117 mBq.kg^{− 1} (n = 3), milk 20 mBq.kg^{− 1} (n = 1) and cereal 290 (n = 1) mBq.kg^{− 1} of fresh weight, respectively. The annual intake and ingestion dose due to ²¹⁰Po was estimated by DDS and MBS in adults, adolescents and children. The overall results showed that the MBS was moderately higher than the DDS in all age groups. Moreover, a DDS approach may even be more realistic, as cooked foodstuffs are used for dietary exposure assessment.

Conclusion: The study confirms that the current levels of ²¹⁰Po do not pose a significant radiological risk to the local inhabitants.

Keywords::

• Duplicate diet
• market basket
• ²¹⁰
• Po
• intake
• ingestion dose

Acknowledgements

The authors would like to thank Dr Vijayalakshmi Venkatesan from NIN for her valuable suggestions.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This work was supported by Board of Research in Nuclear Science (BRNS), Department of Atomic Energy (DAE), Govt. of India for the research funding (Grant No: 2008/36/58–BRNS) and SRM University.