Table 1: Results from a literature search on studies of heavy metal(loid) tolerance in the field. The ISI database was queried1) for works that evaluated alterations in ‘Membrane transport’, ‘Rhizosphere’, ‘Root architecture’ or metal ‘Chelation/Sequestration’ in actual field trials. Searches were done separately for As, Cd, Hg and Zn spanning 2008 to 2021.