Screening of Soil Amendment as a Potential Urban Garden Soil Lead Remediation Treatment

Abstract

Lead contamination in urban soils is a widespread problem caused by industry, leaded paint, and lead additives in gasoline up until the 1970’s. Methods are now being developed to treat the lead on site so that it no longer poses a health threat. One method that has proven effective is phosphate fertilizers, although results and rate requirements differ for each soil. The objective of this study was to evaluate the effectiveness of a commercial fertilizer-like product in immobilizing lead in contaminated soil intended for an urban garden. To do this, treatment was applied and allowed to incubate and was then analyzed for soil solution lead and relative bioavailability. While soil solution lead was significantly reduced, relative bioavailability was relatively unaffected. These results suggest the treatment would be effective for reducing the amount of lead that would be available to plants, but would not be effective in reducing exposure through direct soil ingestion.