Biosolids compost amendment for reducing soil lead hazards: a pilot study of Orgro® amendment and grass seeding in urban yards

At 1-year post-treatment, grass cover was healthy and reductions in bioaccessible Pb concentrations compared to pre-tillage were 64% (from 1655 to 595 mg kg−1) and 67% (from 1381 to 453 mg kg−1) at the sampling lines closest to the houses. Little or no reduction in bioaccessible Pb concentration was observed at sampling lines more remote from the house that also had the lowest bioaccessible Pb concentrations at pre-tillage (620 and 436 mg kg−1, respectively). For the control soils, changes over time in total Pb and bioaccessible Pb concentrations and the bioaccessible Pb fraction were insignificant. This study confirms the viability of in situ remediation of soils in urban areas where children are at risk of high Pb exposure from lead in paint, dust and soil.