Changes in triazine and chloroacetanilide concentrations during natural and artificial treatment by bank filtration, ozonation, filtration, and chlorination were measured in water for the public water supply of Lincoln, Nebraska, U.S.A. The City's water supply is affected by induced infiltration and transport of herbicides from the Platte River in late spring and early summer. The objective of the study was to evaluate the effect of infiltration and treatment on the presence of triazines and chloroacetanilides in drinking water. Samples of river water, well water, and public-supply water at various stages of water treatment were collected during spring runoff from 1997 through 1999 when the presence of herbicides in the Platte River is largest. In 1999, parent herbicide compounds were reduced by 76% of the concentration present in river water. Metabolites of herbicides for which analytical techniques existed were reduced by 21%. However, increases in concentrations of specific metabolite compounds were identified after bank filtration and ozonation. Our findings suggest that ozonation of water in part can shift the risk to human health associated with the consumption of the water from the parent herbicide compounds to their degradation products. See water.usgs.gov/owq/dwi
Learning Objectives: At the conclusion of the session the participant will be able to describe the effect of riverbank filtration and chemical disinfection on concentrations of triazine herbicides in river water.
Keywords: Drinking Water Quality, Pesticide Contamination
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: U.S. Geological Survey
I have a significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.
Relationship: Employment