Transfer and bioaccumulation of ²¹⁰Po from soil to water spinach (Ipomoea aquatica Forrsk.) in Vietnam

Highlights

• ²¹⁰Po concentration in water spinach is high compared to other vegetables.

• Annual effective doses between 292 and 1704 μSv.year-1 for the edible parts.

• Flooded and unflooded variety has similar ²¹⁰Po concentration in the leaf and stem.

• Flooded variety has higher activity concentration in the roots.

• Growing environment influences transfer factors.

Abstract

The water spinach (Ipomoea aquatica Forrsk.) is a common vegetable and a part of the staple diet in Vietnam. It has a well-known tendency for the high absorption of lead, including the radioactive isotope ²¹⁰Pb. ²¹⁰ Pb day to ²¹⁰Po, which is one of the most toxic radioactive isotopes when ingested. Currently, there are few data available on the activity concentration or transfer parameters of water spinach grown in Vietnam. To provide this data, in this study, the ²¹⁰Po activity concentrations in the soil, water and the roots, stems, and leaves of two types of spinach (grown in soil flooded with water and grown in normal soil) in Hanoi, Vietnam were determined by alpha spectrometry. The order of activity concentrations for water spinach grown in unflooded was C_stem < C_leaf < C_root, while for flooded C_stem ≈ C_root < C_leaf. The transfer factors followed a similar pattern.