Human health risk from arsenical pesticide contaminated soils: A long-term greenhouse study

► Soil arsenic bioaccessibility is dependent on soil aging. ► Soil aging led to a decrease in cancer risk for arsenical pesticide amended soils. ► Organic arsenical changed to inorganic as a function of equilibration time. ► Excess cancer risk for 3 of the 4 soils was above USEPA's acceptable range.