Processes controlling geogenic arsenic distribution in soils formed from iron-rich sedimentary rocks.

Soils formed from Fe-rich sedimentary rocks can contain elevated As contents. Although the geogenic origin of As in these soils is recognized, the processes controlling its distribution within soil profiles and its mobility in topsoils are still unclear, limiting effective prediction of soils with potentially hazardous As contents for human health/ecosystems. We investigated 10 soil profiles (0-85 cm) formed from the As- and Fe-rich Aubange Formation in Belgian Lorraine.

Environmental bioavailability of arsenic, nickel and chromium in soils impacted by high geogenic and anthropogenic background contents.

High arsenic, chromium and nickel in soils can pose a hazard to the ecosystem and/or human health. Large areas can be affected by elevated potentially toxic elements (PTE) background contents, entailing a significant effort for managing the potential risk. Assessing the environmental hazard associated to PTE-contaminated soils requires the determination of soil PTE environmental bioavailability, which reflects the capacity of these elements to be transferred to living organisms.