Dietary Exposure to Organophosphorus Pesticides and Neurobehavioral Effects in a Large Multi-City Cohort

EPA Grant Number: FP917129
Title: Dietary Exposure to Organophosphorus Pesticides and Neurobehavioral Effects in a Large Multi-City Cohort
Investigators: Curl, Cynthia Leigh
Institution: University of Washington
EPA Project Officer: Michaud, Jayne
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


Organophosphorus (OP) pesticide exposure in the general U.S. population is believed to be dominated by the dietary pathway. Although research suggests that long-term low-level exposure to OP pesticides may be associated with neurobehavioral changes in occupationally exposed groups or in children living in agricultural communities, no research to date has examined the health impacts of dietary exposure to OP pesticides within the general population. This research project will examine the relationship between chronic dietary exposures to OP pesticides and neurobehavioral outcomes in a multi-city, multi-ethnic cohort of approximately 5,500 non-occupationally exposed participants.


Americans spend more than $20 billion each year on organic foods (grown without most pesticides). Although low-level pesticide exposure had been associated with neurobehavioral changes in farmworkers and in children living in farming communities, little is known about the health impacts of dietary exposure to pesticides in the general population. This project examines the relationship between dietary pesticide exposure and neurobehavioral outcomes in over 5,000 people from six U.S. cities.


This project will build on the existing Multi-Ethnic Study of Atherosclerosis (MESA), an NHLBI-funded cardiovascular cohort study that includes participants recruited from 6 US cities. MESA began in 1999, and all participants completed a comprehensive baseline clinic exam that included, among many other components, a food frequency questionnaire (FFQ) and urine sample collection. Subsequent clinic exams have occurred approximately every two years, and in 2010-2011, participants will return for their fifth exam. Exam 5 will include a comprehensive suite of neurocognitive tests, urine sample collection, and a repeated FFQ, to which this research project adds questions about organic food consumption. This research project will then utilize the FFQ data from both Exams 1 and 5 to conduct an assessment of chronic dietary exposure to OP pesticides based on the foods reported, typical pesticide residue levels from the USDA’s Pesticide Data Program, and processing factors for the method of food preparation from the EPA’s OP Cumulative Risk Assessment of 2006. Urinary biomarkers of OP pesticides will be used to assess the reasonableness of these estimates. The association between dietary OP pesticide exposure and a specific set of neurobehavioral outcomes (including measures of attention, concentration, complex visual-motor processing and executive function, and short-term memory) will be examined.

Expected Results:

This project will be the first large-scale epidemiologic investigation of the health impacts of dietary exposures to OP pesticides. This large cohort is extremely well characterized, with available information on demographics and socioeconomics, employment history, residential history, health status, medication use, and other variables, each of which can be considered in the analysis. The dietary exposure assessment component of this study will incorporate data covering a ten-year period, and will be evaluated in comparison with the results of repeated urinary biomarker analyses. Finally, the neurobehavioral outcomes that are already being measured in MESA are consistent with those found to be relevant in previous occupational research. This project provides a unique opportunity to leverage existing data on dietary patterns and neurobehavioral outcomes, and to add to these data information on organic food consumption practices and urinary biomarker analyses.

Potential to Further Environmental/Human Health Protection:

The results of this project will help inform policy regarding the safety of current agricultural practices with respect to OP pesticides, and to inform the public about the degree to which reducing dietary exposures to pesticides can impact their health.

Supplemental Keywords:

organophosphorus pesticides, organic, dietary exposure, neurobehavioral changes, urinary metabolites,

Progress and Final Reports:

  • 2011
  • 2012
  • Final