The bioaccessibility to the human gastrointestinal (GI) system of Pb and Cd in ingested soil was
measured using the modified physiologically based extraction test (PBST) procedure [24]. 0.5g soil was
shaken (30rpm) with syntentic gastric solution (50ml 0.4 mol/L glycine, pH 2±0.5) for 1h at 37ć. When
extraction was complete, the solution was immediately passed through at 0.22-μm pore-site Millipore
filter and measured using ICP-MS. Pb and Cd bioaccessibility were expressed as percentage of metal
mass extracted by PBET with respect to the metal mass in soil.