Agroclimatic variation in mineral and heavy metal levels of Raphanus sativus L. Microgreens grown in West Bengal

Microgreens have emerged as potent ‘functional foods’ or ‘superfoods’ because of their rich nutritional profile. This research aims to perform Flame Atomic Absorption Spectroscopy based estimation of minerals, heavy metals, and associated health risks of Raphanus sativus L. microgreens grown in different agroclimatic zones of West Bengal, India. The radish microgreens were cultivated in soils collected from different districts (as confirmed by soil analysis), and the mineral content (Ca, Mn, Zn, Se) and heavy metals (Cr, Cd, Pb) were analysed using a Flame Atomic Absorption Spectrometer. Significant variations (p<0.05) in mineral profiles were found in radish microgreens grown in soils of different districts. Major elements determined were Calcium (1091.43±21.87 to 1481.17±12.58 mg/kg); Zinc (44.21±1.54 to 158.92±1.21 mg/kg); Manganese (66.21±8.73 to 83.47±6.43 mg/kg); and Selenium (0.32±0.13 to 1.01±0.22 mg/kg). South 24 Parganas recorded exceptionally high zinc content in the grown microgreens. Chromium concentration was below toxic limits. Lead and cadmium were found in negligible amounts (1.57±0.63 to 11.21±2.02 μg/kg). The hazard index of microgreens grown in all districts was less than 1. A positive correlation between heavy metals indicates that their source and route of uptake are similar. Almost all investigated microgreens were good sources of minerals, with the best mineral profile and high germination rate rich alluvial soils, indicating that fertile soils are best for growth. Based on the obtained results, these microgreens might be further assessed for any seasonal variation in mineral content and in vivo bioavailability studies of minerals needs to be analyzed.