Natural radioactivity determination in samples of Peperomia pellucida commonly used as a medicinal herb

The concentration of 238U, 232Th, 230Th, 226Ra, 228Ra and 210Pb were determined in samples of Peperomia pellucida and in the surrounding soil, by alpha spectrometry and gross alpha and beta counting. The radionuclide activity concentrations ranged from 4.3 to 38 Bq kg−1, 1.7–124 Bq kg−1, 2.1–38 Bq kg−1, 8.5–37 Bq kg−1, 3.2–46 Bq kg−1, 39–93 Bq kg−1, respectively. In the plant extractions and infusions as used for consumption, the mean recoveries were from 23% to 60% in maceration and 24–75% in infusion.

► Natural radioactivity was studied in the medicinal plant Peperomia pellucida.
► The plant, soil and extraction in maceration and infusion were determined.
► The transfer factor soil-to-plant ratio was determined.
► Percentages above 50% of 226Ra and 228Ra were observed in the plant extracts.