title: Polar metabolites of polycyclic aromatic compounds from fungi are potential soil and groundwater contaminants.
abstract: This study investigated the sorption to soil of water-soluble metabolites from polycyclic aromatic compounds (PACs). The soil fungus Cunninghamella elegans was used to produce PAC metabolites from two un-substituted PACs (phenanthrene, pyrene), three alkyl-substituted PACs (2-methylnaphthalene, 1-methylphenanthrene, 1-methylpyrene), and one sulfur-containing heterocyclic PAC (dibenzothiophene). Fifty-eight metabolites were tentatively identified; metabolites from the un-substituted PACs were hydroxylated and sulfate conjugated, whereas metabolites from alkyl-substituted PACs were sulfate conjugated and either hydroxylated or oxidized to carboxylic acids at the methyl group. The metabolism of the sulfur-containing heterocyclic PAC resulted in sulfate conjugates. The sorption of the PAC metabolites to three soils was determined using a batch equilibrium method, and partition coefficients (Kd's) were calculated for fourteen representative metabolites. Sulfate conjugated metabolites displayed Kd's below 70 whereas the metabolites with both a sulfate and a carboxylic acid group had Kd's below 2.8. The low Kd's of water-soluble PAC metabolites indicate high mobility in soil and a potential for leaching to surface- and groundwaters.
authors.affiliation: University of Copenhagen, Faculty of Science, Plant and Environmental Sciences, Analytical Chemistry Group, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark. Electronic address: eboll@life.ku.dk.
authors.forename: Esther S
authors.initials: ES
authors.lastname: Boll
authors.affiliation: Geological Survey of Denmark and Greenland (GEUS), Department of Geochemistry, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark.
authors.forename: Anders R
authors.initials: AR
authors.lastname: Johnsen
authors.affiliation: University of Copenhagen, Faculty of Science, Plant and Environmental Sciences, Analytical Chemistry Group, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
authors.forename: Jan H
authors.initials: JH
authors.lastname: Christensen
mesh_terms: D000327:Adsorption; D020093:Cunninghamella / Q000378:metabolism*; D060587:Groundwater; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry* / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000378:metabolism
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical
keywords: Cunninghamella elegans; K(d) coefficients; Metabolites; Polycyclic aromatic compounds; Soil sorption