Development of Engineered Natural Organic Sorbents for Environmental Applications: 3. Reducing PAH Mobility and Bioavailability in Contaminated Soil and Sediment Systems

摘要

The effects of engineered natural organic amendments on two measures of the environmental "availability" of polycyclic aromatic hydrocarbons (PAHs) associated with soil and sediment samples are assessed. Two soils spiked with pyrene alone and a sediment spiked with a mixture of 4 PAH compounds were amended with raw or superheated-water processed peat or soybean stalks, then aged for periods of either 62 or 105 days. The aged soils were then examined with respect to bioaccumulation of spiked pyrene by earthworms (Eisenia foetida), and to its human bioaccessibility as measured by extraction with simulated gastrointestinal fluid. Additions of processed amendments reduced both measures of availability by factors ranging from 7.6 to 27.0 for earthworm bioaccumulation and from 2.3 to 8.8 for gastrointestinal extractability. All PAH compounds spiked to the sediment were reduced to varying extents in their availabilities to £ foetida and leachabilities by water by both processed and raw organic amendments.