Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Linking desorption kinetics to phenanthrene biodegradation in soil.
AU - Rhodes, Angela
AU - McAllister, Laura E.
AU - Semple, Kirk T.
PY - 2010/5
Y1 - 2010/5
N2 - The desorption of polycyclic aromatic hydrocarbons (PAHs) often exhibits a biphasic profile similar to that observed for biodegradation whereby an initial rapid phase of degradation or desorption is followed by a phase of much slower transformation or release. Most investigations to-date have utilised a polymeric sorbent, such as Tenax, to characterise desorption, which is methodologically unsuitable for the analysis of soil. In this study, desorption kinetics of 14C-phenanthrene were measured by consecutive extraction using aqueous solutions of hydroxypropyl-β-cyclodextrin (HPCD). The data indicate that the fraction extracted after 24 h generally approximated the linearly sorbed, rapidly desorbing fraction (Frap), calculated using a three-compartment model. A good linear correlation between phenanthrene mineralised and Frap was observed (r2 = 0.89; gradient = 0.85; intercept = 8.20). Hence HPCD extraction (24 h) and first-order three-compartment modelling appear to provide an operationally straightforward tool for estimating mass-transfer limited biodegradation in soil. Aqueous hydroxypropyl-β-cyclodextrin (HPCD) solutions can predict the rapidly desorbing and microbially degradable fractions of phenanthrene in soils.
AB - The desorption of polycyclic aromatic hydrocarbons (PAHs) often exhibits a biphasic profile similar to that observed for biodegradation whereby an initial rapid phase of degradation or desorption is followed by a phase of much slower transformation or release. Most investigations to-date have utilised a polymeric sorbent, such as Tenax, to characterise desorption, which is methodologically unsuitable for the analysis of soil. In this study, desorption kinetics of 14C-phenanthrene were measured by consecutive extraction using aqueous solutions of hydroxypropyl-β-cyclodextrin (HPCD). The data indicate that the fraction extracted after 24 h generally approximated the linearly sorbed, rapidly desorbing fraction (Frap), calculated using a three-compartment model. A good linear correlation between phenanthrene mineralised and Frap was observed (r2 = 0.89; gradient = 0.85; intercept = 8.20). Hence HPCD extraction (24 h) and first-order three-compartment modelling appear to provide an operationally straightforward tool for estimating mass-transfer limited biodegradation in soil. Aqueous hydroxypropyl-β-cyclodextrin (HPCD) solutions can predict the rapidly desorbing and microbially degradable fractions of phenanthrene in soils.
KW - PAHs
KW - Bioaccessibility
KW - Desorption kinetics
KW - Two and three-compartment models
KW - Rapidly desorbing fraction
U2 - 10.1016/j.envpol.2010.01.008
DO - 10.1016/j.envpol.2010.01.008
M3 - Journal article
VL - 158
SP - 1348
EP - 1353
JO - Environmental Pollution
JF - Environmental Pollution
SN - 0269-7491
IS - 5
ER -