Pesticide soil sorption parameters: theory, measurement, uses, limitations and reliability.
The soil sorption coefficient Kd and the soil organic carbon sorption coefficient KOC of pesticides are basic parameters used by environmental scientists and regulatory agencies worldwide in describing the environmental fate and behavior of pesticides. They are a measure of the strength of sorption of pesticides to soils and other geosorbent surfaces at the water/solid interface, and are thus directly related to both environmental mobility and persistence. KOC is regarded as a 'universal' parameter related to the hydrophobicity of the pesticide molecule, which applies to a given pesticide in all soils. This assumption is known to be inexact, but it is used in this way in modeling and estimating risk for pesticide leaching and runoff. In this report we examine the theory, uses, measurement or estimation, limitations and reliability of these parameters and provide some 'rules of thumb' for the use of these parameters in describing the behavior and fate of pesticides in the environment, especially in analysis by modeling.
Wauchope
R Don
RD
US Department of Agriculture-Agricultural Research Service, PO Box 748, Tifton, GA 31794, USA. don@tifton.cpes.peachnet.edu
Yeh
Simon
S
Linders
Jan B H J
JB
Kloskowski
Regina
R
Tanaka
Keiji
K
Rubin
Baruch
B
Katayama
Arata
A
Kördel
Werner
W
Gerstl
Zev
Z
Lane
Michael
M
Unsworth
John B
JB
D000327:Adsorption; D000465:Algorithms; D001578:Benzopyrans / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D002855:Chromatography, Thin Layer / Q000379:methods; D006812:Humic Substances / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008954:Models, Biological; D010575:Pesticides / Q000378:metabolism*; D015203:Reproducibility of Results; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000378:metabolism*; D014867:Water / Q000378:metabolism; D014872:Water Movements
D001578:Benzopyrans; D006812:Humic Substances; D010575:Pesticides; D012987:Soil; D012989:Soil Pollutants; D014867:Water; D002244:Carbon; C005023:fulvic acid