Contract No. 68-02-3688; prepared for U.S. Environmental Protection Agency. Bibliography p. 33-34. "Draft." "Project Officer: David C. Sanchez."--T.p.

Various combinations of glyphosate production wastestreams were subjected to biological treatment following lime-pretreatment to reduce high levels of glyphosate. Bench scale biological treatment demonstrated that glyphosate did not appear to interfere with the bilogical degradation process at concentrations up to 105 mg/L. On the other hand, glyphosate itself showed only partial reduction with biological treatment (28 to 45 percent). The mechanism of this removal is not fully understood but may include sorption on sludge. No evidence for metabolism of glyphosate was generated in oxygen uptake studies. While the test does not provide any evidence for metabolic uptake of glyphosate, it is also interesting to note that fairly high concentrations of the compound do not inhibit other microbial processes in acclimated sludge. Bilogical treatment significantly reduced the toxicity of these effluents to algae (Selenastrum capricarnutum) and invertebrates (Daphnia magna). Additional treatment options were investigated in an attempt to reduce glyphosate concentrations in the bilogically treated effluents. These options included ozonation, adsorption, and ion exhange[sic]. These treatment options provided only marginal reduction of glyphosate concentrations in biologically treated effluents.