Assessing the oral bioaccessibility of potentially toxic elements in urban area of Belfast using an oven for sample incubation

Previous research work has shown elevated concentrations of potentially toxic elements (PTEs) in Belfast soils and in some cases, these exceed the Suitable 4 Use Levels. However, these measurements are total concentrations and... [ view full abstract ]

Previous research work has shown elevated concentrations of potentially toxic elements (PTEs) in Belfast soils and in some cases, these exceed the Suitable 4 Use Levels. However, these measurements are total concentrations and not all the PTEs present in soil are bioaccessible to humans. Applying the Unified Barge Method (UBM) to mimic the human gastrointestinal digestion, the current research aims to assess the risks posed to human health in the situation of soil ingestion. Geochemical datasets used for this study are provided by the Geological Survey of Northern Ireland (GSNI) which were sampled during the Tellus project. Firstly, this research proposes to set up the UBM using an oven for sample incubation. The efficiency of this low-cost device has been previously demonstrated in comparison with a heated water bath, both giving similar results. After installation, the validation of UBM will be assessed by replicating samples already extracted via a heated water bath, in a study conducted for the rural soils in Northern Ireland. Once, the configuration of the UBM is confirmed, oral bioaccessibility will be assessed for 100 soil samples retrieved from the GSNI. Selected samples will cover the urban area of Belfast with a representative range of rocks, different soil types and regions with sensitive receptors.
The outcomes of this study are expected to provide valuable information for local authorities concerning human health risk assessment and could be extrapolated to other regions which present similar geochemical properties.