A Comparative Analysis of the Oral Bioaccessibility of Metals/Metalloids Determined Using the Unified Bioaccessibility Research Group of Europe Method and 0.07 M HCl Single Extraction Method

Metals and metalloids in consumer products can be ingested by humans and cause health problems. The unified Bioaccessibility Research Group of Europe (BARGE) method (UBM, i.e., ISO 17924), with complex digestive ingredients, and the 0.07 M HCl single extraction method, as a simplified means, have been widely used to assess oral bioaccessibility in vitro. Herein, the bioaccessible concentrations of metals and metalloids in 13 certified reference materials acting as surrogates for consumer products were determined using the UBM and the 0.07 M HCl single extraction method and compared. The bioaccessible concentrations of metals and metalloids evaluated using the UBM and the 0.07 M HCl single extraction method ranged from 0.002 to 17,449 mg/kg and from 0.003 to 20,283 mg/kg, respectively; their bioaccessibility ranged from 0.00002 to 26.9% and from 0.00002 to 36.6%, respectively. The 0.07 M HCl single extraction method showed higher concentrations, as the bioaccessible concentrations of metals and metalloids differed by 1.38 times (i.e., the slope of the linear regression), indicating its potential for conservative assessment. However, the Student’s t-test results for the 12 metals and metalloids showed no significant differences (p-value ≥ 0.05). It demonstrated that the relatively simple 0.07 M HCl single extraction method can be used as an in vitro test method to assess the oral bioaccessibility of metals and metalloids in various consumer products by replacing the UBM and/or through its use as a screening method prior to the application of the UBM, thereby moving towards green analytical chemistry.