Abstract
It is well known that xenobiotics sorp to solid phases like soil and sediment, depending on their
inherent properties and environmental conditions. Traditionally it was accepted, that the hydrophobicity
of the chemical, i.e. the log KOW, as well as the solid’s content of organic carbon (OC)
were the parameters describing the extent of sorption. Realizing that ionizable chemicals like
weak acids and bases not always sorb according to their hydrophobicity, a correcting factor has
been suggested. Correcting the hydrophobic sorption according to the Henderson-Hasselbalch
equation has recently shown to improve the predicted sorption of weak acids significantly,
however, weak bases do still show discrepancies compared with experimental data. In this investigation
it was studied how a range of electrostatic parameters have influence on the sorption of
weak bases to solid phases. Besides log KOW, pH and OC content of the solids, this investigation
also included parameters like clay, silt and sand content, cation exchange capacity, zeta potential
and other properties of the solids, and the impact on the sorption of weak bases to solids. Weak
bases with pKa-values differing about half a unit in the range 4-9, resulting in ionization within
an environmental relevant pH range, are selected for the study. Literature is searched for data
on distribution coefficients (log KD) where also information about the experimental conditions
regarding electrostatic parameters was reported. Taking the above mentioned parameters into
consideration, predictions and regressions of the distribution to solids shall be improved.
Original language | English |
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Title of host publication | Ecosystem Protection in a Sustainable World: A Challenge for Science and Regulation : Abstract Book |
Number of pages | 109 |
Publisher | SETAC Europe |
Publication date | 2011 |
Publication status | Published - 2011 |
Event | SETAC Europe 21st Annual Meeting: Ecosystem Protection in a Sustainable World: A Challenge for Science and Regulation - Milano Convention Centre, Milano, Italy Duration: 15 May 2011 → 19 May 2011 Conference number: 21 http://milano.setac.eu/home/?contentid=291&pr_id=290 |
Conference
Conference | SETAC Europe 21st Annual Meeting |
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Number | 21 |
Location | Milano Convention Centre |
Country/Territory | Italy |
City | Milano |
Period | 15/05/2011 → 19/05/2011 |
Internet address |