title: Combining Leaching and Passive Sampling To Measure the Mobility and Distribution between Porewater, DOC, and Colloids of Native Oxy-PAHs, N-PACs, and PAHs in Historically Contaminated Soil.
abstract: Different methods to quantify soil porewater concentrations of contaminants will provide different types of information. Passive sampling measurements give freely dissolved porewater concentrations (Cpw,free), while leaching tests provide information on the mobile concentration (Cpw,leach), including contaminants associated with dissolved organic carbon (DOC) and particles/colloids in the porewater. This study presents a novel combination of these two measurements, to study the sorption and mobility of polycyclic aromatic compounds (PACs) to DOC and particulate organic carbon (POC) in 10 historically contaminated soils. The PACs investigated were polycyclic aromatic hydrocarbons (PAHs), oxygenated-PAHs, and nitrogen containing heterocyclic PACs. Observed Cpw,leachwas up to 5 orders of magnitude higher than Cpw,free; implying large biases when Cpw,leachis used to assess bioavailability or soil partitioning. Sorption of PACs to DOC and POC was important for the mobility of compounds with log KOW> 4. Average DOC/water-partitioning coefficients (KDOC) correlated well with KOW(log KDOC= 0.89 × log KOW+1.03 (r2= 0.89)). This relationship is likely more accurate for historically contaminated soils than previously published data, which suffer from artifacts caused by problems in measuring Cpw,freecorrectly or not using historically contaminated soils. POC/water-partitioning coefficients (KPOC) were orders of magnitude larger than corresponding KDOC,suggesting sorption to mobile particles/colloids is the dominant mechanism for PAC mobility.
authors.affiliation: Swedish Geotechnical Institute (SGI), SE-581 93 Linköping, Sweden.
authors.forename: Anja
authors.initials: A
authors.lastname: Enell
authors.affiliation: Department of Chemistry, Umeå University , SE 901 87 Umeå, Sweden.
authors.forename: Staffan
authors.initials: S
authors.lastname: Lundstedt
authors.affiliation: Norwegian Geotechnical Institute (NGI), P.O. Box 3930, Ullevål Stadion, N-0806 Oslo, Norway.
authors.forename: Hans Peter H
authors.initials: HP
authors.lastname: Arp
authors.affiliation: Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences , Box 7050, SE-75007 Uppsala, Sweden.|Geological Survey of Sweden (SGU), Box 670, SE-751 28 Uppsala, Sweden.
authors.forename: Sarah
authors.initials: S
authors.lastname: Josefsson
authors.affiliation: Norwegian Geotechnical Institute (NGI), P.O. Box 3930, Ullevål Stadion, N-0806 Oslo, Norway.|Department of Analytical Chemistry and Environmental Sciences (ACES), Stockholm University , SE-10691 Stockholm, Sweden.|Institute of Environmental Sciences (IMV), Norwegian University of Life Sciences (NMBU) , P.O. Box 5003, NO-1432 Ås, Norway.
authors.forename: Gerard
authors.initials: G
authors.lastname: Cornelissen
authors.affiliation: Swedish Geotechnical Institute (SGI), SE-581 93 Linköping, Sweden.
authors.forename: Ola
authors.initials: O
authors.lastname: Wik
authors.affiliation: Swedish Geotechnical Institute (SGI), SE-581 93 Linköping, Sweden.|Department of Soil and Environment, Swedish University of Agricultural Sciences , Box 7014, SE-750 07 Uppsala, Sweden.
authors.forename: Dan
authors.initials: D
authors.lastname: Berggren Kleja
mesh_terms: D002244:Carbon; D003102:Colloids; D011084:Polycyclic Aromatic Hydrocarbons; D011083:Polycyclic Compounds; D012987:Soil; D014874:Water Pollutants, Chemical
chemical_list: D003102:Colloids; D011084:Polycyclic Aromatic Hydrocarbons; D011083:Polycyclic Compounds; D012987:Soil; D014874:Water Pollutants, Chemical; D002244:Carbon