Prediction and experimental evaluation of soil sorption by natural hormones and hormone mimics.
Surface runoff from manure-fertilized fields is a significant source of endocrine-disrupting compounds (EDCs) in the environment. Sorption by soils may play a major role in the environmental fate of manure-borne EDCs, including 17α- and 17β-estradiol (17α-E2 and 17β-E2), estrone (E1), melengestrol acetate (MGA), 17α- and 17β-trenbolone (17α-TB and 17β-TB), trendione (TND), and zeranol (α-ZAL). As a measure of sorption behavior, the organic carbon-normalized partition coefficients (K(OC)) of 17β-E2, E1, MGA, and α-ZAL were experimentally determined for three agricultural soils with initial EDC concentrations spanning from ∼0.01 to >1 μM. Sorption isotherms were linear for most solute-soil combinations. Measured K(OC) values were compared to those predicted using a suite of single-parameter and polyparameter linear free energy relationships (sp- and pp-LFERs). Sp-LFER models were based on experimentally determined octanol-water partition coefficients (K(OW)), whereas pp-LFER solute descriptors were calculated indirectly from experimentally determined solvent-water partition coefficients or the program ABSOLV. Log K(OC) predictions by sp-LFERs were closest to the experimentally determined values, whereas pp-LFER predictions varied considerably due to uncertainties in both solute and sorbent descriptors determined by ABSOLV or estimates using the partition coefficient approach.
Environmental Science Graduate Program, The Ohio State University, 125 South Oval Mall, Columbus, Ohio 43210, USA.
Marcella L
ML
Card
Yu-Ping
YP
Chin
Linda S
LS
Lee
Bushra
B
Khan
D000327:Adsorption; D052244:Endocrine Disruptors / Q000737:chemistry*; D004958:Estradiol / Q000737:chemistry; D004970:Estrone / Q000737:chemistry; D005308:Fertilizers; D006728:Hormones / Q000737:chemistry*; D008372:Manure; D012987:Soil / Q000737:chemistry*; D015029:Zeranol / Q000031:analogs & derivatives / Q000737:chemistry
D052244:Endocrine Disruptors; D005308:Fertilizers; D006728:Hormones; D008372:Manure; D012987:Soil; C029659:zearalenol; D004970:Estrone; D004958:Estradiol; D015029:Zeranol