WRRCSR No. 7.1:85 Desorption and Leachability of Residual DBCP and EDB from Soils and Saprolite
Year: 1985
Type: report
Abstract: Pesticides applied to pineapple fields in central O'ahu to control nematode populations have been detected in groundwater drawn from the underlying aquifer. These nematicides have persisted in surface soils and deep saprolite despite their discontinued use. The leachability of these pesticide residues from soil and their subsequent movement will determine whether or not they constitute a continued threat to groundwater quality. In this study, leachability is assessed by sorption-desorption measurements and is characterized by distribution coefficients and the kinetics of release of sorbed residues. Two methods for characterizing sorption-desorption processes have been developed that exploit the tendency of these fumigant pesticides to vaporize. Both methods analyze the vapor phase of a soil-pesticide system. The indirect sorption method results in a determination of distribution coefficients and the purge system results in a characterization of the kinetics of desorption. Experiments using the indirect sorption method to determine distribution coefficients for a surface soil obtained from central O'ahu have been initiated. Preliminary work using the purge system is also underway. The new sorption-desorption methods will be used to determine the leachability of DBCP and EDB residues in soil and saprolite obtained from central O'ahu.
Authors: Richard E. Green, Frank L. Peterson, Donna S. Buxton
Language: English
Subfield: Pollution
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2297887357