title: Polycyclic Aromatic Acids Are Primary Metabolites of Alkyl-PAHs-A Case Study with Nereis diversicolor.
abstract: Although concentrations of alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) in oil-contaminated sediments are higher than those of unsubstituted PAHs, only little attention has been given to metabolism and ecotoxicity of alkyl-PAHs. In this study we demonstrated that metabolism of alkyl-PAHs primarily forms polycyclic aromatic acids (PAAs). We generalize this to other alkyl-PAHs, based on literature and the present study of the metabolism of 1-methylphenanthrene, 3,6-dimethylphenanthrene, and 1-, 2-, 3-, and 6-methylchrysene related to their unsubstituted parent PAHs. Also, we observed that body burdens and production of PAAs was related to the position of the methyl group, showing the same isomer specific preferences as for microbial degradation of alkyl-PAHs. We detected a high production of PAAs, and larger metabolism of alkyl-PAHs than their unsubstituted parent PAHs. We therefore propose that carboxylic acid metabolites of alkyl-PAHs have the potential of constituting a new class of contaminants in marine waters that needs attention in relation to ecological risk assessments.
authors.affiliation: †Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg, Denmark.|‡Department of Environmental, Social and Spatial Change, Roskilde University, Universitetsvej 1, P.O. Box 260, DK-4000 Roskilde, Denmark.
authors.forename: Linus M V
authors.initials: LM
authors.lastname: Malmquist
authors.affiliation: ‡Department of Environmental, Social and Spatial Change, Roskilde University, Universitetsvej 1, P.O. Box 260, DK-4000 Roskilde, Denmark.
authors.forename: Henriette
authors.initials: H
authors.lastname: Selck
authors.affiliation: §Faculty of Science and Technology, University of Stavanger, 4036 Stavanger, Norway.
authors.forename: Kåre B
authors.initials: KB
authors.lastname: Jørgensen
authors.affiliation: †Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg, Denmark.
authors.forename: Jan H
authors.initials: JH
authors.lastname: Christensen
mesh_terms: D000818:Animals; D002911:Chrysenes / Q000737:chemistry; D005453:Fluorescence; D007448:Invertebrates / Q000378:metabolism*; D055442:Metabolome; D010616:Phenanthrenes / Q000737:chemistry; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D014867:Water / Q000737:chemistry
chemical_list: D002911:Chrysenes; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D014867:Water; C031181:phenanthrene