HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Guenzi, W. D. Articles by Beard, W. E. Search for Related Content PubMed Articles by Guenzi, W. D. Articles by Beard, W. E. Agricola Articles by Guenzi, W. D. Articles by Beard, W. E.

The Effects of Temperature and Soil Water on Conversion of DDT to DDE in Soil¹

ABSTRACT

A laboratory study was conducted to determine the rates of DDT (1,1,1-trichloro-2,2-bis [p-chlorophenyl] ethane) degradation and DDE (1,1-dichloro-2,2-bis [p-chlorophenyl] ethylene) formation in soil. Degradation rates increased with higher temperatures and in the presence of water. Of the DDT mixed with Raber silty clay loam, 82.1, 74.5, 53.2, and 38.3% was recovered as DDT and 6.7, 12.5, 21.6, and 34.8% as DDE after 140 days incubation at 30, 40, 50, and 60C, respectively. A comparison of DDE formation in sterile and nonsterile soil showed that 84% of the conversion was due to a chemical process at 30C and 91% at 60C. In sterile systems at 30C, rates of DDE formation were similar in submerged soil and soil at 1/3 bar suction, and both were much higher than in air-dried soil.

Key Words: pesticide • insecticide • chemical degradation • persistence • decomposition • microbial degradation

¹ Contribution from U. S. Dep. of Agric., Agric. Res. Serv., Western Region, P. O. Box E, Fort Collins, CO 80522, in cooperation with Colorado State Univ. Exp. Stn., Sci. J. Ser. No. 2049.

² Soil Scientist and Chemist, USDA.

Received for publication June 2, 1975.