Bioavailability of residual polycyclic aromatic hydrocarbons following enhanced natural attenuation of creosote-contaminated soil.
The impact of residual PAHs (2250 +/- 71 microg total PAHs g(-1)) following enhanced natural attenuation (ENA) of creosote-contaminated soil (7767 +/- 1286 microg total PAHs g(-1)) was assessed using a variety of ecological assays. Microtox results for aqueous soil extracts indicated that there was no significant difference in EC(50) values for uncontaminated, pre- and post-remediated soil. However, in studies conducted with Eisenia fetida, PAH bioaccumulation was reduced by up to 6.5-fold as a result of ENA. Similarly, Beta vulgaris L. biomass yields were increased 2.1-fold following ENA of creosote-contaminated soil. While earthworm and plant assays indicated that PAH bioavailability was reduced following ENA, the residual PAH fraction still exerted toxicological impacts on both receptors. Results from this study highlight that residual PAHs following ENA (presumably non-bioavailable to bioremediation) may still be bioavailable to important receptor organisms such as earthworms and plants.
Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095, Australia. albert.juhasz@unisa.edu.au
Albert L
AL
Juhasz
Euan
E
Smith
Natasha
N
Waller
Richard
R
Stewart
John
J
Weber
D048908:Aliivibrio fischeri / Q000187:drug effects; D000818:Animals; D027461:Beta vulgaris / Q000187:drug effects / Q000254:growth & development; D001673:Biodegradation, Environmental; D002849:Chromatography, Gas; D003407:Creosote / Q000032:analysis*; D009835:Oligochaeta / Q000378:metabolism*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000493:pharmacokinetics* / Q000633:toxicity; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis* / Q000633:toxicity; D013021:South Australia; D018675:Toxicity Tests
D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; D003407:Creosote