Oral bioaccessibility of metals in an urban catchment, Newcastle upon Tyne

The metal content was determined in soils from a former, historic, contaminated land site and now a ‘green' public open space in N.E. England. Using a systematic sampling grid approach, 32 soil samples were taken from locations across the site and analyzed for six potentially toxic elements (Cd, Cr, Cu, Ni, Pb, and Zn). Initially, the pseudo-total metal content of the soils was determined using acid digestion followed by inductively coupled plasma mass spectrometry analysis. This data was evaluated against published soil guideline value (SGV) and generic assessment criteria (GAC) values; it was found that 21% (i.e., 41 samples) exceeded the stated lower values. The data was then compared to the oral bioaccessibility of the soils, which was assessed by an in-vitro gastrointestinal extraction procedure. The results, determined as the % BAF, indicated that overall bioaccessibility was low (