Further validation of the HPCD-technique for the evaluation of PAH microbial availability in soil

• Published in: Environmental pollution (1987) 2006-11, Vol.144 (1), p.345-354
• Main Authors: Doick, Kieron J., Clasper, Paula J., Urmann, Karina, Semple, Kirk T.
• Format: Article
• Language: English
• Subjects: 2-Hydroxypropyl-beta-cyclodextrin; Adsorption; Analysis methods; analytical chemistry; Applied sciences; Bacteria - metabolism; beta-Cyclodextrins; Bioavailability; Biodegradation, Environmental; Biological and physicochemical properties of pollutants. Interaction in the soil; Co-contaminants; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Monitoring - methods; Exact sciences and technology; extraction; hydroxypropyl-beta-cyclodextrin; methodology; non-exhaustive extraction technique; phenanthrene; Phenanthrenes; Poaceae; Pollution; Pollution, environment geology; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Polycyclic Aromatic Hydrocarbons - metabolism; Pyrenes; Soil and sediments pollution; Soil Microbiology; soil microorganisms; Soil Pollutants - analysis; soil pollution; Sorption-desorption; Time; Trees; validity
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2005.10.054

There is currently considerable scientific interest in finding a chemical technique capable of predicting bioavailability; non-exhaustive extraction techniques (NEETs) offer such potential. Hydroxypropyl-beta-cyclodextrin (HPCD), a NEET, is further validated through the investigation of concentration ranges, differing soil types, and the presence of co-contaminants. This is the first study to demonstrate the utility of the HPCD-extraction technique to predict the microbial availability to phenanthrene across a wide concentration range and independent of soil-contaminant contact time (123d). The efficacy of the HPCD-extraction technique for the estimation of PAH microbial availability in soil is demonstrated in the presence of co-contaminants that have been aged for the duration of the experiment together in the soil. Desorption dynamics are compared in co-contaminant and single-PAH contaminated spiked soils to demonstrate the occurrence of competitive displacement. Overall, a single HPCD-extraction technique proved accurate and reproducible for the estimation of PAH bioavailability from soil. HPCD extractions can determine the microbial availability of PAHs in mixtures and over a range of concentrations.