Life Sciences Commons^™

Herbicide Toxicity To Non-Target Aquatic Organisms Does Not Increase In Mixtures With Surfactants, Courtney L. Telfort

Honors College Theses

Agricultural herbicides enter aquatic environments after rain events where they affect microscopic aquatic plants (phytoplankton) and animals (zooplankton) that form the base of aquatic food webs. Atrazine, an herbicide with low solubility in water, is often mixed with surfactants such as alkyl polyglucoside (APG) to improve effectiveness. Although APG has low-toxicity, a potential drawback to increased atrazine solubility is greater adverse effects on aquatic organisms. I hypothesized that atrazine and APG decrease phytoplankton abundance more than atrazine alone. Specifically, I predicted phytoplankton abundance should 1) decrease with increasing concentrations of the mixture compared to the same atrazine concentrations individually, and …