|Lentz, Rodrick - Rick|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract only
Publication Acceptance Date: 8/16/2004
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Water-soluble polyacrylamide (PAM) used to reduce erosion in furrow irrigated fields and other agriculture applications contains, less than 0.05% Acrylamide monomer (AMD). The AMD is a potent neurotoxicant and suspected carcinogen, and is readily dissolved and transported in flowing water. Deep percolation beneath furrow-irrigated fields ranges from 7 to 325 mm per crop season. Thus, AMD may leach into the vadose zone beneath PAM-treated fields. We measured the AMD in water leached below the crop root zone in a furrow-irrigated Portneuf silt loam. Vacuum operated percolation samplers were used to monitor soil water flux, and collect leachate water. The samplers were placed at 1.2 m depths at 30 m and 150 m across a 180-m-long corn field that was furrow irrigated using PAM (10 mg/L during furrow advance). Percolation water and furrow inflows were monitored for AMD during and after three furrow irrigations. The samples were analyzed for AMD using Gas Chromatography and an electron detector. Furrow inflows contained an average AMD concentration of 5.5 ug/L. The AMD in percolation water samples never exceeded the minimum detection limit, i.e. less than 0.5 ug/L. The risk that groundwater beneath these PAM-treated furrow irrigated soils will be contaminated with AMD appears minimal.