Combined Toxicity of Pesticides in Drinking Water: A Sustainable Optimization of Current Drinking Water Treatment Oxidation and Carbon Filtration Methods

EPA Grant Number: FP917149
Title: Combined Toxicity of Pesticides in Drinking Water: A Sustainable Optimization of Current Drinking Water Treatment Oxidation and Carbon Filtration Methods
Investigators: Saylor, Greg L
Institution: University of Cincinnati
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2010 through August 31, 2013
Project Amount: $111,000
RFA: STAR Graduate Fellowships (2010) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Pesticides and Toxic Substances


The purpose of this project is to address the toxic mixtures that are created in drinking water by pesticides and their degradates that have the potential of expressing greater toxicities when mixed. In addition, traditional oxidation practices used in drinking water treatment may worsen the situation through the creation of more toxic by-products. This project will explore the effects of chemical disinfection processes on pesticides present in drinking water.


This project will consider the effects of drinking water treatment processes on the toxicity of pesticides that can be present in contaminated water sources. Water will be tested before and after treatment to understand how toxicity changes. One of the key aspects of this work will be studying the toxicity of mixtures. Understanding these mixtures will allow drinking water utilities to identify best management practices for producing the safest drinking water possible.


The primary objective of this project is to learn more about the complex interactions of toxic substances in mixtures. The project will be completed in three phases. First, toxicity data will be obtained through testing single pesticides as well as controlled mixtures. Second, a laboratory treatment system will be used to determine the optimum operating conditions to minimize effluent toxicity with synthetic influent spiked with pesticides. The system will consist of two batch reactors: pre-disinfection using potassium permanganate, and post-disinfection using chlorine. A granular activated carbon (GAC) filter will be applied to simulate processes employed by a local, currently impacted drinking water treatment plant. This leads to the third phase, where the same system will be utilized to treat pesticide-impacted lake water samples.

Expected Results:

There are two major expected results of this study. First, this study will provide a better understanding of the toxicity of commonly used pesticides, both individually and in mixtures. This information will be very important in assessing the toxic effect of multiple pesticides present in water samples. Second, this study will provide more information about the effect of drinking water treatment processes on pesticides that may be present in the influent. Understanding the effects of the treatment processes combined with the toxicity information will allow for the determination of an optimal treatment system/configuration that will minimize the toxicity of the finished drinking water.

Potential to Further Environmental/Human Health Protection:

This project directly relates to the safety of drinking water from pesticide-impacted sources. Many pesticides persist in soil and water and have been linked with both environmental and human health concerns. Understanding synergism, antagonism, and the impact of conventional oxidation practices on mixtures of pesticides will help regulators and water utilities produce the safest drinking water possible.

Supplemental Keywords:

pesticides, drinking water, toxicity, disinfection, oxidation, microtox,

Progress and Final Reports:

  • 2011
  • 2012
  • Final