title: Characterization of non-extractable ¹⁴C- and ¹³C-sulfadiazine residues in soil including simultaneous amendment of pig manure.
abstract: Recently, we reported on soil fate of SDZ residues amended with pig manure treated with ¹⁴C-labeled sulfadiazine ¹⁴C-SDZ). The first objective of the present study was to determine whether this strategy can be substituted by application of ¹⁴C-SDZ to soil. The second objective was to characterize non-extractable SDZ residues by fractionation, size exclusion chromatography (SEC) and solid state ¹³C-NMR. The fate of ¹⁴C-SDZ was examined for 28 d, using two soils with and without amendment of pig manure. Mineralization of ¹⁴C-SDZ was low; extractable residues decreased to 7-30%. Compared to the previous study, results were similar. ¹⁴C-SDZ derived bound radioactivity was found in HCl-washings, fulvic, humic acids and humin. According to SEC, one bound ¹⁴C portion (70%) co-eluted with fulvic acids (above 910 g mol⁻¹); the other consisted of adsorbed/entrapped ¹⁴C-SDZ. The ¹³C-SDZ study was performed for 30 d; humic acids were examined by ¹³C-NMR. A signal (100-150 ppm) was referred to ¹³C-SDZ. SEC and ¹³C-NMR demonstrated rapid integration of SDZ into humics.
authors.affiliation: Institute of Environmental Research, RWTH Aachen University, Aachen, Germany. thorsten.junge@bio5.rwth-aachen.de
authors.forename: Thorsten
authors.initials: T
authors.lastname: Junge
authors.forename: Katrin Charlot
authors.initials: KC
authors.lastname: Meyer
authors.forename: Katrin
authors.initials: K
authors.lastname: Ciecielski
authors.forename: Alina
authors.initials: A
authors.lastname: Adams
authors.forename: Andreas
authors.initials: A
authors.lastname: Schaffer
authors.forename: Burkhard
authors.initials: B
authors.lastname: Schmidt
mesh_terms: D000327:Adsorption; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification; D002247:Carbon Isotopes / Q000032:analysis; D004350:Drug Residues / Q000737:chemistry* / Q000302:isolation & purification; D006812:Humic Substances / Q000032:analysis; D007700:Kinetics; D008372:Manure / Q000032:analysis*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000737:chemistry* / Q000302:isolation & purification; D013411:Sulfadiazine / Q000737:chemistry* / Q000302:isolation & purification; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents; D002247:Carbon Isotopes; D006812:Humic Substances; D008372:Manure; D012987:Soil; D012989:Soil Pollutants; D013411:Sulfadiazine