title: Changes in hydrocarbon groups, soil ecotoxicity and microbiology along horizontal and vertical contamination gradients in an old landfarming field for oil refinery waste.
abstract: Horizontal and vertical contaminant gradients in an old landfarming field for oil refinery waste were characterised with the aim to assess parallel changes in hydrocarbon groups and general, microbiological and ecotoxicological soil characteristics. In the surface soil polar compounds were the most prevalent fraction of heptane-extractable hydrocarbons, superseding GC-FID-resolvable and high-molar-mass aliphatics and aromatics, but there was no indication of their relatively higher mobility or toxicity. The size of the polar fraction correlated poorly with soil physical, chemical and microbiological properties, which were better explained by the total heptane-extractable and total petroleum hydrocarbons (TPH). Deleterious effects on soil microbiology in situ were observed at surprisingly low TPH concentrations (0.3%). Due to the accumulation of polar and complexed degradation products, TPH seems an insufficient measure to assess the quality and monitor the remediation of soil with weathered hydrocarbon contamination.
authors.affiliation: Department of Food and Environmental Sciences, Division of Microbiology, University of Helsinki, Helsinki, Finland. anu.s.mikkonen@helsinki.fi
authors.forename: Anu
authors.initials: A
authors.lastname: Mikkonen
authors.forename: Kati P
authors.initials: KP
authors.lastname: Hakala
authors.forename: Kaisa
authors.initials: K
authors.lastname: Lappi
authors.forename: Elina
authors.initials: E
authors.lastname: Kondo
authors.forename: Anu
authors.initials: A
authors.lastname: Vaalama
authors.forename: Leena
authors.initials: L
authors.lastname: Suominen
mesh_terms: D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001673:Biodegradation, Environmental; D017753:Ecosystem; D006838:Hydrocarbons / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D007220:Industrial Waste / Q000032:analysis*; D007700:Kinetics; D010578:Petroleum / Q000032:analysis / Q000378:metabolism* / Q000633:toxicity; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity
chemical_list: D006838:Hydrocarbons; D007220:Industrial Waste; D010578:Petroleum; D012987:Soil; D012989:Soil Pollutants