Mac The Vinh1,2, Truong Ngoc Minh4 and Nguyen Thi Minh Tu1,3
1 School of Chemistry and Life Sciences, Hanoi University of Science and Technology, Vietnam
2 Hanoi University of Industry, Vietnam
3 New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai, Miyagi, Japan
4 Center for High Technology Research and Development – Vietnam Academy of Science and Technology, Vietnam
Mac, Th. V., Truong, N. M. & Nguyen, Th. M. T. (2026). Ultra-trace alkali metals and geographic origin of Pak choi growing in the Northern Vietnam. Bulg. J. Agric. Sci., 32(3), 546–558
Metal content in soils of pak choi (Brassica rapa L. ssp. chinensis) from four different districts in Northern Vietnam (Me Linh, Long Bien, Dan Phuong, and Chuong My district) was investigated for 26 metals (Li, B, Mg, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Nb, Mo, Ag, Cd, Sb, Cs, Ba, Hg, Tl, Pb, Bi), using inductively coupled plasma mass spectrometry (ICP-MS). Samples were collected during six consecutive planting periods from September 2022 to December 2022, and from January 2023 to April 2023. The obtained data were processed with discriminant analysis, demonstrating the ability to identify the geographic origin of pak choi based on ultra-trace alkali metals (UTAM) (including Lithium (Li), Cesium (Cs) and Rubidium (Rb).
Ultra-trace alkali metals content in pak choi and soils of the three main cultivated areas in two different districts of Northern Vietnam (Me Linh and Dan Phuong District) was investigated using the ICP-MS method during three consecutive planting periods from January 2023 to April 2023. The obtained data were processed with MANOVA (multivariate analysis of variance), and described by graphs. The results showed relationships between UTAM levels in pak choi edible parts (stems and leaves), inedible parts (roots), and soil, with Rb appearing to play a significant role in pak choi growth. Among the three metals of UTAM, Rb has the potential to become a biomarker for tracing geographic origin of pak choi.