2013 Progress Report: Pesticide Exposure Pathways

EPA Grant Number: R834514C002
Subproject: this is subproject number 002 , established and managed by the Center Director under grant R834514
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: University of Washington Center for Child Environmental Health Risks Research (2010)
Center Director: Faustman, Elaine
Title: Pesticide Exposure Pathways
Investigators: Faustman, Elaine
Institution: University of Washington
EPA Project Officer: Callan, Richard
Project Period: October 1, 2010 through September 24, 2016
Project Period Covered by this Report: September 25, 2012 through September 24,2013
RFA: Children's Environmental Health and Disease Prevention Research Centers (with NIEHS) (2009) RFA Text |  Recipients Lists
Research Category: Children's Health , Health

Objective:

Since 1998, researchers of the University of Washington Center for Child Environmental Health Risks Research (the Center) have been using a multi-disciplinary research approach working in the lab, in the field, and in the community to understand the mechanisms that define children’s susceptibility to pesticides, identify the implications of this susceptibility for development and learning, and partner with our communities to translate our findings into risk communication, risk management, and prevention strategies. The Center is jointly funded by the National Institute of Environmental Health Sciences (NIEHS) and the Environmental Protection Agency (EPA).
 
The Center is administratively housed within the Institute for Risk Analysis and Risk Communication, also directed by Center Director Dr. Elaine M. Faustman, which is in the University of Washington’s School of Public Health. The Center includes partnerships with the Fred Hutchinson Cancer Research Center and the Yakima Valley community, located in the agricultural center of Washington State, to jointly sponsor a Community Based Participatory Research (CBPR) Project aimed at reducing childhood pesticide exposure.
 
All Center efforts are highly integrated with two field-based research projects, two laboratory-based research projects, three facility cores, an Administrative Core, and Faculty Development Investigator.
 
The specific objectives of the two field-based projects—the CBPR project and the pesticide exposure pathways research project—are:
 
  1. To improve our understanding of critical pathways of potential pesticide exposure for children; and
  2. To apply culturally-appropriate interventions to reduce children’s exposure to pesticides.

The Pesticide Exposure Pathways Research Project’s overall aim is to develop a systematic understanding of residential pesticide exposure pathways arising from proximity to agricultural spraying in rural agricultural communities where children live. The proximity exposure pathway is due to transport of pesticides from applied fields to homes and other settings. The mechanisms of transport include spray drift, volatilization, re‐suspension and deposition of particles containing pesticides. The Pesticide Exposure Pathways Research Project studies both local pesticide application factors and human activity factors that contribute to childhood exposure to pesticides.

Progress Summary:

The highlights of this past year include air sampling to measure concentrations of airborne organophosphate pesticides (chlorpyrifos, azinphos-methyl) and oxon analogs at 20 participant homes. Chemical analysis using LC-MS-MS in the Environmental Health Laboratory was completed for ~150 samples. The data analysis for the initial results has been prepared for publication. Fieldworker observation and public land-use data were used to specify type of crop for proximal homes, emphasizing homes that were near tree fruit fields. This information will be used on the next stage of analysis for building exposure models.
 
These efforts address key aims of the current study by directly measuring exposures to OP pesticides inside and outside the participant homes and examining the potential contribution of the take-home and proximity pathways. PUF-PAS (polyurethane foam passive air sampling) disks have been developed and tested as a novel sampling device for studying pesticide exposures. PUF-PAS is highly effective for capturing airborne organophosphate pesticides while minimizing invasiveness to research participant families. Over 90% of the study participants that were approached participated in the air monitoring portion of the study, and only one passive sampling instrument had a failure. A paper has been submitted describing this new sampling method.
 
Our initial field results show that residences proximal (<250 m) to fields experience higher monthly outdoor levels of chlorpyrifos and azinphos-methyl than non-proximal homes (> 250 m). Farmworker homes also experienced higher levels of outdoor pesticide concentrations, but this may be attributable to a relationship between increased proximity to tree fruit orchards and increased outdoor pesticide concentrations. Many farmworker homes were located in agriculturally dense areas. This is the first major study to validate a passive sampling device for OP pesticides and their oxon analogs. Passive sampling provides average exposures estimates over the course of several days and will dramatically enhance our ability to survey more participants and to collect samples over the course of an entire season. Both proximity and take home routes contribute essentially independently to airborne OP pesticide exposures. This information will be a direct benefit for constructing exposure estimates for longer term epidemiological cohort studies in the future.

Future Activities:

The highlights above illustrate the high volume and quality of the Center'’s efforts aiming at reducing the adverse effects of environmental pesticide exposures in children. The Center continues to work to understand the mechanisms that define children’s susceptibility to pesticides, identify the implications of this susceptibility for health impacts on development and learning, and partner with our communities to translate our findings into risk communication, risk management, and prevention strategies. Center researchers continue to work in the lab, in the field, and in the community to bring a unique and successful approach to the study of children’s environmental health.

Journal Articles:

No journal articles submitted with this report: View all 33 publications for this subproject

Supplemental Keywords:

RFA, Scientific Discipline, Health, INTERNATIONAL COOPERATION, ENVIRONMENTAL MANAGEMENT, Biochemistry, Children's Health, Environmental Policy, Biology, Risk Assessment, pesticide exposure, age-related differences, pesticides, children's vulnerablity, biological markers, agricultural community

Relevant Websites:

http://depts.washington.edu/chc/ Exit

Progress and Final Reports:

Original Abstract
  • 2011 Progress Report
  • 2012
  • 2014
  • 2015 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R834514    University of Washington Center for Child Environmental Health Risks Research (2010)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R834514C001 Community-Based Participatory Research
    R834514C002 Pesticide Exposure Pathways
    R834514C003 Molecular Mechanisms
    R834514C004 Genetic Susceptibility