Bioavailability and Bioaccessibility of Cd in Low and High Cd Uptake Affinity Cultivars of Brassica rapa ssp. Chinensis L. (Pakchoi) using an In vitro Gastrointestinal and Physiologically-based Extraction Test

In vitro oral bioaccessibility of Cadmium (Cd) in two low (XGSJ), (SHQI) and two high (CGBC), (SIYM) Cd-accumulating affinity cultivars of Brassica rapa ssp. chinensis L. (pak choi) grown on Cd-contaminated Alfisol soil was assessed. In this study, physiologically based extraction test (PBET) and in vitro gastrointestinal (IVG) were chosen to assess the bioaccessibility for Cd by stimulating human digestion of plant material. The pak choi cultivars were grown on Cd-contaminated soil with six different Cd concentrations (0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mg kg(-1)). The phytoavailability of Cd in soils was also measured through Mehlich-3 extraction and sequential extraction method. Plants were harvested and analyzed for their total Cd content and afterward extracted using PBET and IVG to provide the estimate of oral bioaccessibility for the human health risks of metal contamination in pak choi.