Safety of gardening on lead- and arsenic-contaminated urban brownfields

Elevated levels of lead (Pb) and arsenic (As) are not uncommon for urban soils. Test plots were established at urban gardens in Tacoma and Seattle, WA. The Tacoma site was contaminated with Pb (51-312 mg kg) and As (39-146 mg kg), and the Seattle site had high Pb soil concentrations ranging from 506 to 2022 mg kg and As concentrations of carrot > tomato. Food-chain transfer of Pb and As in vegetables grown in contaminated urban soils were reduced by laboratory cleaning.Phillip P. Defoe, Ganga M. Hettiarachchi, Christopher Benedict, and Sabine Marti