title: Sorption to black carbon of organic compounds with varying polarity and planarity.
abstract: It is becoming increasingly clear that the products of incomplete combustion (soot and charcoal, collectively termed black carbon or BC) can be responsible for as much as 80 - 90% of the total sorption to sediments of aromatic, planar, and hydrophobic compounds such as polycyclic aromatic hydrocarbons or planar polychlorinated biphenyls. In the present study, it was investigated whether a nonpolar aliphatic compound (hexachloroethane) and three nonplanar bipolar compounds with different functional groups [free electron pairs but no aromatic ring (butylate) or free electron pairs and an aromatic ring (diuron, atrazine)] would also show strong and nonlinear sorption to a BC-enriched sediment. At a concentration of 1 ng/L, the extent of elevated BC sorption compared to total organic carbon (TOC) sorption increased in the order atrazine < hexachloroethane < butylate < diuron. Rationalization of the differences between the sorbates was attempted in terms of dispersive and steric effects. This study shows that the effects of strong BC sorption apply to a broader range of organic contaminants than previously thought, and the results will aid in a better understanding of BC sorption mechanisms and improved fate modeling of contaminants in the environment.
authors.affiliation: Department of Applied Environmental Science, Stockholm University, 10691 Stockholm, Sweden. gerard.cornelissen@ngi.no
authors.forename: Gerard
authors.initials: G
authors.lastname: Cornelissen
authors.forename: Joris
authors.initials: J
authors.lastname: Haftka
authors.forename: John
authors.initials: J
authors.lastname: Parsons
authors.forename: Orjan
authors.initials: O
authors.lastname: Gustafsson
mesh_terms: D000327:Adsorption; D001280:Atrazine / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D004237:Diuron / Q000737:chemistry*; D004980:Ethane / Q000031:analogs & derivatives* / Q000737:chemistry; D006540:Herbicides / Q000737:chemistry*; D006358:Hot Temperature; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D013859:Thiocarbamates / Q000737:chemistry*
chemical_list: D006540:Herbicides; D006843:Hydrocarbons, Chlorinated; D013859:Thiocarbamates; C023898:butylate; D002244:Carbon; D004237:Diuron; C010182:hexachloroethane; D004980:Ethane; D001280:Atrazine