Water, Air, and Soil Pollution

, Volume 87, Issue 1, pp 231–243

Fate of sludge-applied silicones in agricultural soil microcosms


  • R. G. Lehmann
    • Health and Environmental SciencesDow Corning Corporation
  • C. L. Frye
    • Health and Environmental SciencesDow Corning Corporation
  • D. A. Tolle
  • T. C. Zwick

DOI: 10.1007/BF00696839

Cite this article as:
Lehmann, R.G., Frye, C.L., Tolle, D.A. et al. Water Air Soil Pollut (1996) 87: 231. doi:10.1007/BF00696839


Our previous publications showed that silicone (polydimethylsiloxane, or PDMS) polymers degrade to monomeric silanols and eventually to C02 in laboratory soil incubations. In this study, 200 cs14C-PDMS was added to soil microcosms (Tuscola sandy loam and Fargo silty clay) in anaerobically digested sludge. Soybeans followed by wheat were grown for 7 months during which microcosms were subjected to 3 leaching events. Recoveries of14C in the microcosms ranged from 47 to 90%. The recovered14C was almost completely in the soils, with trace amounts in leachate and ≤ 2% of the total in plant shoots. Extraction of soils coupled with HPLC-GPC showed that the majority of soill4C was still polymeric, but with lower molecular weight than the original PDMS. From 1 to 5% of the remaining14C was probably small silanols. Results thus confirm laboratory studies and show that PDMS degradation occurs under conditions similar to the field.

Download to read the full article text

Copyright information

© Kluwer Academic Publishers 1996