Temporal changes in the extractability, bioaccessibility and biodegradation of target hydrocarbons in soils from former refinery facilities

Abstract This study investigated the extractability, bioaccessibility and biodegradation of 14C-phenanthrene 14C-octacosane in two soils from former oil refinery facilities over 341 days. The impact biostimulation bioaugmentation treatments was also evaluated. At 0, 31, 62, 124 days, loss extractability (using dichloromethane, methanol:water hydroxypropyl-?-cyclodextrin (HPCD)) 14C-hydrocarbons were measured. Further at each time point, mineralisation measured respirometrically under different conditions. In general, extractions with methanol: water HPCD similar for both hydrocarbons treatments; however, these values less that those DCM. Overall, significantly higher (p ? 0.05) amounts lost, readily extracted mineralised soils, having little upon degradation this hydrocarbon Conversely, increased residues sustained after 31 Surprisingly, under-predicted extent to which contaminants degraded point. Determining likelihood effective by stimulation indigenous microorganisms or through needs be assessed chemical biological measurements bioaccessibility, rather than just is totally extractable soil. However, have high loadings organic matter and/or may prevent accurate assessment contaminant as HPCD.