Assessment of health risks linked to natural radionuclides contained in vegetables from ex-mining, and non-mining land

Agriculture in former tin mining areas can increase the absorption of radionuclides, thus posing potential health risks. This study measured Ra-226, Th-232, and K-40 in eleven vegetable species from former mining sites and thirteen from non-mining sites using HPGe gamma spectrometry. The concentrations ranged from 0.18 to 12.76 Bq/kg (Ra-226), 0.19–16.05 Bq/kg (Th-232), and 37.85–494.67 Bq/kg (K-40), while in non-mining areas they ranged from 0.63 to 4.53 Bq/kg, 0.19–16.05, and 186.29–494.67 Bq/kg, respectively. The activity concentration has exceeded the UNSCEAR reference value, with water-rich vegetables (yellow velvetleaf, water spinach) showing higher absorption. The estimated annual effective dose was 95.54 × 10⁻⁶ Sv/year in former mining areas, and 86.55 × 10⁻⁶ Sv/year in non-mining areas, well below the ICRP limit (1 mSv/year). The cancer risks were 32.11 × 10⁻⁶ and 12.10 × 10⁻⁶, also below the ICRP threshold. This first comparative assessment in Indonesia highlights crop-specific uptake but does not include soil data. Although the risk remains low, the results underscore the need for monitoring and guidance on land use to support food security and reclamation in Southeast Asia, and Africa.