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Title: Effects of Sorbate speciation on sorption of selected Sulfonamides in three loamy soils
Author (s): Kurwadkar, Sudarshan T.
Adams, Craig D.
Meyer, Michael T.
Kolpin, Dana W.
Department/Lab Affiliations: Civil, Architectural & Environmental Engineering
Environmental Research Center
Keywords: Antimicrobials
Soil pH
Soil sorption
Speciation
Sulfamethazine
Sulfathiazole
Sulfonamides
Issue Date: 2007
Publisher: American Chemical Society
Citation: Kurwadkar, S., Adams, C., Meyer, M., Kolpin, D. (2007) “Effects of Sorbate Speciation on Sorption of Selected Sulfonamides in Three Loamy Soils,” J. Agriculture and Food Chemistry, 55, 1370-1376.
Abstract: Sorption of sulfamethazine (SMN) and sulfathiazole (STZ) was investigated in three soils, a North Carolina loamy sand, an Iowa sandy loam, and a Missouri loam, under various pH conditions. A significant increase in the sorption coefficient (KD) was observed in all three soils, as the sulfonamides converted from an anionic form at higher pH to a neutral/cationic form at lower pH. Above pH 7.5, sulfonamides exist primarily in anionic form and have higher aqueous solubility and no cationic character, thereby consequently leading to lower sorption to soils. The effect of speciation on sorption is not the same for all sulfonamides; it is a function of the pH of the soil and the pKa of the sulfonamides. The results indicate that, for the soils under investigation, SMN has comparatively lower KD values than STZ. The pH-dependent sorption of sulfonamides was observed to be consistent in all three soils investigated. The KD values for each speciated form-cationic, neutral, and anionic-were calculated using an empirical model in which the species-specific sorption coefficients (KD0, KD1, and KD2) were weighted with their respective fractions present at any given pH.
Type: Article - Journal
text
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titleEffects of Sorbate speciation on sorption of selected Sulfonamides in three loamy soils
contributor.authorKurwadkar, Sudarshan T.
contributor.authorAdams, Craig D.
contributor.authorMeyer, Michael T.
contributor.authorKolpin, Dana W.
contributor.deptlabCivil, Architectural & Environmental Engineering
contributor.deptlabEnvironmental Research Center
contributor.sponsorGeological Survey
contributor.sponsorMissouri department of natural resources
subjectAntimicrobials
subjectSoil pH
subjectSoil sorption
subjectSpeciation
subjectSulfamethazine
subjectSulfathiazole
subjectSulfonamides
date.issued2007
publisherAmerican Chemical Society
identifier.citationKurwadkar, S., Adams, C., Meyer, M., Kolpin, D. (2007) “Effects of Sorbate Speciation on Sorption of Selected Sulfonamides in Three Loamy Soils,” J. Agriculture and Food Chemistry, 55, 1370-1376.
identifier.pub.URI
http://pubs.acs.org/cgi-bin/abstract.cgi/jafcau/2007/55/i04/abs/jf060612o.html
description.abstractSorption of sulfamethazine (SMN) and sulfathiazole (STZ) was investigated in three soils, a North Carolina loamy sand, an Iowa sandy loam, and a Missouri loam, under various pH conditions. A significant increase in the sorption coefficient (KD) was observed in all three soils, as the sulfonamides converted from an anionic form at higher pH to a neutral/cationic form at lower pH. Above pH 7.5, sulfonamides exist primarily in anionic form and have higher aqueous solubility and no cationic character, thereby consequently leading to lower sorption to soils. The effect of speciation on sorption is not the same for all sulfonamides; it is a function of the pH of the soil and the pKa of the sulfonamides. The results indicate that, for the soils under investigation, SMN has comparatively lower KD values than STZ. The pH-dependent sorption of sulfonamides was observed to be consistent in all three soils investigated. The KD values for each speciated form-cationic, neutral, and anionic-were calculated using an empirical model in which the species-specific sorption coefficients (KD0, KD1, and KD2) were weighted with their respective fractions present at any given pH.
typeArticle - Journal
type.DCMITypetext
type.statusFinal version
rightsThis material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.
rights.URI
http://pubs.acs.org/instruct/copyright.pdf
date.accessioned2007-04-11T17:00:48Z
date.available2007-10-01T15:51:03Z
identifier.persist.URI
http://scholarsmine.mst.edu/post_prints/EffectsOfSorbateSpeciationOnSorption2_09007dcc803f3c43.html