Accumulation Characteristics of Heavy Metals in American Ginseng (Panax quinquefolium L.) and Changes in Their Contents after Soaking the Plants

Abstract

Understanding the accumulation characteristics of heavy metals in the growth process of American ginseng can provide theoretical support for its safe production. In this study, the content of Cu, Mn, As, Pb, Cd, Cr, and Ni in American ginseng (annual, biennial, and triennial) and planting soil were determined using inductively coupled plasma mass spectrometry (LCP-MS). In addition, the change in the content of these heavy metals in American ginseng was evaluated after soaking the plant for various time periods. The results indicated that the content of some heavy metals in American ginseng was correlated with soil heavy metal contents. For example, Ni, Cd, and Mn content in American ginseng was significantly negatively correlated with Ni content in soil. American ginseng exhibited distinct heavy metal accumulation characteristics in different parts at different growth stages. For example, in annual American ginseng, Mn and As are mainly enriched in lateral roots and taproots, while in biennial and triennial American ginseng, they are mainly enriched in reed heads. When American ginseng plant was soaked for various time intervals, its heavy metal content changed to varying degrees. In general, after soaking American ginseng for 30 min, the content of most heavy metals decreased.