Distribution Characteristics of Nutritional Elements and Combined Health Risk of Heavy Metals in Medicinal Tea from Genuine Producing Area of China

The development of the medicinal tea (MT) system has promoted the health awareness in the whole world, and the nutritional elements are also an important resource of health care delivery except for the medicinal components. Among various medicinal teas, Astragalus membranaceus (AM), Zingiberaceae rhizome (ZR), and Lonicera japonica (LJ) were the most popular ingredients in China. However, except for the nutrition value, MT was inevitably contaminated with heavy metals due to the special planting environment and processing system. This study was aimed to investigate the distribution characteristics of nutrition elements and combined health risk of heavy metals in MT sample, referring to the maximum residue limit (MRL), estimated daily intake (EDI), total target hazard quotients (TTHQs), and lifetime cancer risk (LCR). Furthermore, the bioaccessibility of gastrointestinal phase and bioavailability of human colon adeno carcinoma cell line were selected for elaborating the exact damage degree to human digestive system. The results showed that, the nutritional elements of Na, Se, K, Ca, and Mn were very rich in MT, but a total of 50% of MT were contaminated by Cr, Hg, and Cd in raw material. Although the cumulative lifetime cancer risk can be accepted under the bioaccessibility (26.62–99.27%), the heavy metals of Cr, As, Hg, and Fe in AM and LJ posed a slight threaten of non-carcinogenic risk to consumers. This study will give an exactly assessment of multiple elements in digestive system, thus further to predict the potential health risk under the consumption of MT products.