title: Hydrocarbons in sediments of a chronically contaminated bay: the challenge of source assignment.
abstract: Aliphatic hydrocarbons and 39 PAH (parental and alkylated homologs) determined in ca. 100 sediment samples from the Guanabara Bay, Rio de Janeiro, were evaluated for source discrimination using new approaches. Concentrations of total PAH were in the range of 96-135,000 μg kg(-1) similar to other coastal urbanized embayment. Traditional diagnostic ratios were not as efficient PAH source indicators, e.g. biomass combustion was assigned as the major source of the pyrolytic PAH although the hydrographic basin is highly industrialized and urbanized. It is proved petrogenic imprint cannot be detected if only the 16 USEPA PAH are determined. The high production in the eutrophic system is not apparent in the aliphatic fraction dominated by land derived n-alkanes due to the effectiveness of microbial degradation. The present work demonstrates the complexity of hydrocarbon forensics when applied to chronically contaminated environments.
authors.affiliation: Departamento de Química, Pontifícia Universidade Católica do Rio de Janeiro, 22453-900 Rio de Janeiro, Brazil. angela@puc-rio.br
authors.forename: Angela de L R
authors.initials: Ade L
authors.lastname: Wagener
authors.forename: Maria de Fátima G
authors.initials: Mde F
authors.lastname: Meniconi
authors.forename: Claudia
authors.initials: C
authors.lastname: Hamacher
authors.forename: Cassia O
authors.initials: CO
authors.lastname: Farias
authors.forename: Gilson C
authors.initials: GC
authors.lastname: da Silva
authors.forename: Irene T
authors.initials: IT
authors.lastname: Gabardo
authors.forename: Arthur de L
authors.initials: Ade L
authors.lastname: Scofield
mesh_terms: D061006:Bays; D001938:Brazil; D002244:Carbon / Q000032:analysis; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D006838:Hydrocarbons / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D006838:Hydrocarbons; D014874:Water Pollutants, Chemical; D002244:Carbon