title: Sorption-desorption behavior of polybrominated diphenyl ethers in soils.
abstract: Polybrominated diphenyl ethers (PBDEs) are flame retardants that are commonly found in commercial and household products. These compounds are considered persistent organic pollutants. In this study, we used 4,4'-dibromodiphenyl ether (BDE-15) as a model compound to elucidate the sorption and desorption behavior of PBDEs in soils. The organic carbon-normalized sorption coefficient (K(OC)) of BDE-15 was more than three times higher for humin than for bulk soils. However, pronounced desorption hysteresis was obtained mainly for bulk soils. For humin, increasing concentration of sorbed BDE-15 resulted in decreased desorption. Our data illustrate that BDE-15 and probably other PBDEs exhibit high sorption affinity to soils. Moreover, sorption is irreversible and thus PBDEs can potentially accumulate in the topsoil layer. We also suggest that although humin is probably a major sorbent for PBDEs in soils, other humic materials are also responsible for their sequestration.
authors.affiliation: Department of Soil and Water Sciences, The Robert H Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, PO Box 12, Rehovot 76100, Israel.
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Olshansky
authors.forename: Tamara
authors.initials: T
authors.lastname: Polubesova
authors.forename: Walter
authors.initials: W
authors.lastname: Vetter
authors.forename: Benny
authors.initials: B
authors.lastname: Chefetz
mesh_terms: D000327:Adsorption; D004784:Environmental Monitoring; D005411:Flame Retardants / Q000032:analysis; D055768:Halogenated Diphenyl Ethers / Q000032:analysis / Q000737:chemistry*; D008956:Models, Chemical; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*
chemical_list: D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D012987:Soil; D012989:Soil Pollutants