title: Interactions of triclosan, gemfibrozil and galaxolide with biosolid-amended soils: Effects of the level and nature of soil organic matter.
abstract: Triclosan, gemfibrozil and galaxolide, representing acidic and non-ionized hydrophobic organic compounds, are biologically active and can be accumulated during wastewater treatment in sewage sludge. The interactions of these substances with the soils amended by sewage sludge-originating biosolids may control their environmental fate. Therefore, the sorption of three organic compounds was studied in dune sand, loess soil, clay soil and mixtures of these media with three different sewage sludge-originating biosolids that were incubated under aerobic conditions for 6 months. For each compound, 15 sorption isotherms were produced at pH 7.8-8.0. The sorption of triclosan and gemfibrozil on sand-containing sorbents was examined also under acidic conditions. In some soil series, the compound's Freundlich constants (KF) are linearly related to the soil organic carbon (OC) content. Notably, for a given OC content, the sand-containing sorbents tend to demonstrate enhanced interactions with triclosan and galaxolide. This may be related with more hydrophobic and/or less rigid soil organic matter (SOM) as compared with the clay-containing soils, implying indirect effects of minerals. Generally the OC-normalized KF vary among different soil-biosolid combinations which is explained by the differences in the composition and properties of SOM, and is also contributed by the non-zero intercepts of the linear KF upon soil OC dependencies. The negative intercepts suggest that below a certain OC level no considerable organic compound-soil interactions would occur. Interactions of molecular and anionic forms of triclosan with a sand-containing sorbent may be comparable, but interactions involving gemfibrozil molecules could be stronger than interactions involving its anion.
authors.affiliation: Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel; Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel. Electronic address: alla.usyskin@mail.huji.ac.il.
authors.forename: Alla
authors.initials: A
authors.lastname: Usyskin
authors.affiliation: Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel. Electronic address: nadia@volcani.agri.gov.il.
authors.forename: Nadezhda
authors.initials: N
authors.lastname: Bukhanovsky
authors.affiliation: Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel. Electronic address: vwmichel@volcani.agri.gov.il.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Borisover
mesh_terms: D000327:Adsorption; D000332:Aerobiosis; D000538:Aluminum Silicates / Q000737:chemistry; D001578:Benzopyrans / Q000737:chemistry*; D000077215:Clay; D015248:Gemfibrozil / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D012722:Sewage / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D014260:Triclosan / Q000737:chemistry*
chemical_list: D000538:Aluminum Silicates; D001578:Benzopyrans; D012722:Sewage; D012987:Soil; D012989:Soil Pollutants; C033119:galaxolide; D014260:Triclosan; D015248:Gemfibrozil; D000077215:Clay
keywords: K(FOC); Organic matter; PPCP; Sewage sludge; Soil; Sorption