Retention of estrogenic steroid hormones by selected New Zealand soils

Sorption of estrone and estrone‐3‐sulfate from CaCl2 solution and artificial urine in pastoral soils of New Zealand

“…In contrast, soils with a high SSA have been reported to exhibit limitless sorption potential for estrogens. For instance, Casey et al [33] [20] also observed limitless sorption of E2 in a similar soil from the Horotiu soil series and attributed that to the OC content and the presence of high allophane contents. In contrast to the Horotiu soil, the clay mineralogy of the Hamilton and Te Kowhai soils (Table 1) is dominated by kaolinite and halloysite, with major fractions of amorphous volcanic glass (Te Kowhai) and vermiculite (Hamilton).…”

“…The log K OC values for E1 as a metabolite of E1-3S in the three soils ranged similarly to values that were obtained when E1 sorption was performed as a parent compound. Isotherms for soil sorption of E1 as a metabolite have been reported before [19,20], but as a metabolite of E2, and both studies did not perform a separate batch experiment for E1 as a parent compound. Sarmah et al [20] reported an N value of 0.75 for E1 in a similar soil from Horotiu series from an isotherm constructed using measured sorbed-and solutionphase concentrations during equilibrium of E2 with the soil.…”

“…Sorption of estrogens has been extensively studied over the past decade, and most studies found the sorption potential of agricultural soils to be moderate to high [17][18][19][20] with soil organic matter being the major sorption domain for estrogens [19][20][21]. Sorption nonlinearity typical for organic contaminants [22,23] has also been substantiated for these hormones.…”

“…Although the number of investigated soils in the present study was too small to significantly identify the OC domain as the primary sorbent and E1-3S may exhibit sorption behavior that is not essentially governed by the OC domain, the concentration-dependent K OC data using the lowest equilibrium concentration of 0.25 mg/L are presented. Given the apparent nonlinearity observed in most soil-solute combinations in the present study, we calculated the concentration-dependent effective distribution coefficient (K eff d~K f C N{1 w ) values and the corresponding concentration-dependent OC-normalized partition coefficients (K OC , L/kg OC) for each soil and hormone [20]. In addition, a range of effective distribution coefficients has been calculated for each soil/compound/ mediator-solution combination to account for minimum and maximum exposure concentrations in a pasture environment.…”

“…Both types of information are, however, necessary to address risks associated with hormonal loading from grazed dairy systems. Therefore, batch-equilibration studies were conducted for E1-3S and E1 sorption to three agricultural soils from the Waikato, a major dairying region in New Zealand, using a solvent-extraction technique previously adopted by Lee et al [19] and Sarmah et al [20]. The common approach of employing 5 mM CaCl 2 as a mediator solution was complemented with an artificial cow urine solution.…”