Grantee Research Project Results

2005 Progress Report: Measurements and Models of Longitudinal Dietary Intake of Pyrethroid and Organophosphate Insecticides by Children

EPA Grant Number: R829396
Title: Measurements and Models of Longitudinal Dietary Intake of Pyrethroid and Organophosphate Insecticides by Children
Investigators: MacIntosh, David L. , Ryan, P. Barry , Kerr, William L. , Hassan, Sayed
Current Investigators: Ryan, P. Barry , Kerr, William L. , Hassan, Sayed
Institution: Emory University
Current Institution: Emory University , University of Georgia
EPA Project Officer: Aja, Hayley
Project Period: February 1, 2002 through March 31, 2010
Project Period Covered by this Report: February 1, 2004 through March 31, 2005
Project Amount: $659,764
RFA: Children's Vulnerability to Toxic Substances in the Environment (2001) RFA Text | Recipients Lists
Research Category: Children's Health , Human Health

Objective:

To measure longitudinal dietary exposure of selected insecticides for children, to evaluate the accuracy of children’s dietary exposure models, and to reduce model uncertainty. Our focus is on the validation of biomarkers in children. By measuring environmental media—air, soil, housedust, food—and modeling intake, we will make a direct comparison to biological marker concentrations.

Progress Summary:

Progress has been made on several fronts in this investigation. These may be categorized as Laboratory Methods Development, Children’s Study, Adult Study, and Other Activities. We present a brief synopsis of results in each of these areas.

Laboratory Methods Development

We have completed methods development for extraction and analysis of all environmental samples. Extraction efficiencies are between 75 and 100 percent for all target analytes from each medium. With regard to food, at the time of the report, methods were complete from nondairy beverages, fruits, and vegetables. Completion of other food groups, with the exception of fats and oils, is scheduled for completion by November 1, 2006. Several presentations have been made on the environmental extraction procedures. The first presentation on the food procedures is scheduled for the Southeastern Regional American Chemical Society Meeting in early November. A single, multimedia, multiclass extraction and analysis method for pesticides is a useful contribution to the scientific community.

Children’s Study

Progress on the Children’s Study stopped in March 2005 due to an U.S. Environmental Protection Agency (EPA)-initiated hold on all pesticide exposure studies involving children. This hold was released in August 2006, and final EPA Institutional Review Board (IRB) approval for the study was granted. We are currently in the replanning stage for this study.

Adult Study

In an effort to pilot our protocols for the Children’s Study, we undertook a study of adults working in our research facility. This study involved 11 individuals who kept 4-day duplicate diets, which were separated in nine food categories in accordance with our analysis protocol. Detailed dietary logs were kept as well and each food item was weighed. The adults were asked to fill out an activity questionnaire indicating any activities likely to result in exposure to pesticides. Finally, each adult was asked to supply first morning and last evening void urine samples, plus a last evening void before the duplicate diet, and a first morning void after the duplicate diet (a total of 10 samples) for pesticide metabolite analysis. Two full cycles of this monitoring were completed, and a third started during the reporting period. Analysis of soil and dust samples for Cycles 1 and 2 is scheduled for completion in mid-November. Cycle 1 urine samples have been analyzed by the Centers for Disease Control and Prevention (CDC). Organophosphate metabolite data for Cycle 1 has been forwarded to us for statistical analysis. We are awaiting pyrethroid data and all data from Cycle 2. Cycle 3 samples will be forwarded to CDC upon completion of that Cycle.

Other Activities

We have completed analysis and are preparing a draft manuscript in which data from the National Health and Nutrition Examination Survey 1999-2002 data collection effort focusing on pyrethroid metabolites in urine were analyzed with respect to dietary intake. We have found that certain foods and certain activities are associated with elevated levels of urinary 3-phenoxybenzoic acid, a metabolite of many pyrethroid pesticides.

Journal Articles:

No journal articles submitted with this report: View all 14 publications for this project

Supplemental Keywords:

exposure assessment, pesticides, pyrethroids, organophosphates, biomarkers, pesticide analysis, children,, Health, RFA, Scientific Discipline, Air, PHYSICAL ASPECTS, Toxics, Susceptibility/Sensitive Population/Genetic Susceptibility, Health Risk Assessment, Physical Processes, pesticides, Risk Assessments, genetic susceptability, Children's Health, Biochemistry, air toxics, dietary exposure, sensitive populations, urban air, environmental hazard exposures, biological markers, dust , age-related differences, human exposure, organophosphate pesticides, pesticide exposure, organophosphates, neurotixics, agricultural community, dermal contact, insecticides, monitoring, pesticide residues, longitudinal study, adolescents, children, exposure, rural communities, gender-related variability, multi-pathway study, environmental toxicant, human health risk

Progress and Final Reports:

Original Abstract

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.