Grantee Research Project Results

2005 Progress Report: Pesticide Exposures of Preschool Children Over Time

EPA Grant Number: R829363
Title: Pesticide Exposures of Preschool Children Over Time
Investigators: Wilson, Nancy K. , Chuang, Jane C. , Strauss, Warren J. , Lyu, Christopher
Institution: Battelle Memorial Institute
EPA Project Officer: Aja, Hayley
Project Period: October 1, 2001 through September 30, 2005
Project Period Covered by this Report: October 1, 2004 through September 30, 2005
Project Amount: $1,340,414
RFA: Aggregate Exposure Assessment for Pesticides: Longitudinal Case Studies (2001) RFA Text |  Recipients Lists
Research Category: Pesticides , Human Health , Safer Chemicals

Objective:

The effects on children’s exposures of recent changes in pesticide uses, such as those resulting from the federally mandated phase-outs of residential use of chlorpyrifos and diazinon and the increased use of alternative pesticides, are not established. Thus, the main objective of this research project is to estimate the longitudinal changes in aggregate exposures to targeted pesticides for selected preschool children in the same age group over 4 years.

The variability among preschool children’s exposures in similar microenvironments and among those in different microenvironments is also not well known. Thus, a second objective of this research is to estimate the interpersonal variability of these exposures among preschool children living in different homes and among preschool children living in the same home.

Progress Summary:

The research study, Pesticide Exposures of Preschool Children Over Time (PEPCOT), began in June 2002. The progress and accomplishments of PEPCOT in Year 4 of the project, from June 1, 2005, through May 31, 2006, are summarized below.

Human Subjects Research Protection

Continuation approval by the Battelle Institutional Review Board (IRB), which is required annually, was obtained for Year 4 of the project in October 2005.

Recruitment

In Year 1 of the project, the PEPCOT team successfully met the original recruitment goal of 50 households with 101 participating children. Participant recruitment and retention through the Years 2 through 4 continued to be successful. Two participating households dropped out of the study (a 4% attrition rate), and two were not able to participate (but wanted to stay in the study) in the second year of sampling, because of parents’ busy schedules and lack of time for participation. No households dropped out in the third sampling year. However, two households could not be sampled in the third sampling year, one because of hospitalization of the mother and the other because of a family move to a new residence, with resultant scheduling problems. Forty-eight households completed the study, giving a 96 percent retention rate, and 44 of these (88%) completed all 3 years of sampling. The participating children in these households comprised 50 boys and 47 girls, including five sets of twins and one set of triplets.

Field Sampling

The 50 participating households were each assigned to one of three groups for spring, summer, or fall sampling. Participants in each group were sampled once in each of the 3 years, at approximately the same time of year. In Year 4 of the project, all field sampling was completed. Field activities ended on October 18, 2005.

Samples were collected over a 24-hour period. Microenvironmental sample types included: indoor and outdoor air, indoor floor dust, food preparation surface wipes, and floor surface wipes. Personal samples included children’s liquid and solid food, hand wipes, and first morning urine. For those children still in diapers, overnight diapers were collected. For those children being breast-fed, samples of breast milk were requested, although not always possible to obtain.

Ancillary, interpretive information was collected through use of computer-assisted personal interviewing (CAPI) programs, except for the child activity diaries, which were in a booklet to be filled out by the parents. The CAPI forms included the House/Building Characteristics Observation Survey, the Premonitoring Questionnaire, and the Postmonitoring Questionnaire.

All computer-assisted telephone interviewing and CAPI programs performed automatic quality control (QC) checks during data entry. These checks included range checks, consistency checks, and skip pattern checks.

Laboratory Analysis of Samples

On receipt of multimedia samples, the solid food samples were weighed and homogenized. The volumes of the liquid food samples were measured, the gels from the diaper samples were removed for storage, and the dust samples were sieved to collect the fine (< 150 μm) fractions. All of the collected samples were stored in freezers at temperatures below -10°C pending target chemical analysis.

Chemical analysis is in progress, with more than 20 compounds being measured in different sample matrices. These compounds include 2 organophosphate (OP) pesticides, 2 OP metabolites, 14 pyrethroid pesticides, 4 pyrethroid metabolites, 2 acid herbicides, and 1 phenol.

All indoor and outdoor air, dust, hand wipe, hard-floor surface wipe, food-preparation wipe, and urine samples collected in Sampling Years 1, 2, and 3 have been prepared and analyzed by gas chromatography/mass spectrometry (GC/MS) for the target pollutants/ metabolites. Sample preparation and analysis of the solid food samples for acidic pollutants has been completed. Data for Sampling Years 1 and 2 were imported into the PEPCOT database. The QA/QC checks of the PEPCOT imported data are in progress. Analyses of the remaining samples will be completed in the Year 5 of the project.

A 32-page information booklet for PEPCOT participants, “The PEPCOT Study: Pesticide Exposures of Preschool Children Over Time,” was prepared, reviewed and approved by the Battelle IRB, and sent to each participating household. Each booklet included a chart of the PEPCOT pesticide measurements for the individual household, the range of results for PEPCOT as well as for two other studies of children’s pesticide exposures (The Children’s Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants Study Final Report, EPA/600/R-04/193; Third National Report on Human Exposure to Environmental Chemicals, Centers for Disease Control and Prevention, 2005), and supplementary material on ways to reduce children’s exposures to pesticides in and around their homes.

Future Activities:

In Year 5 of the project, laboratory analysis of the remaining collected samples, statistical analysis of the data, and manuscript preparation for journal publication of PEPCOT results will be completed.

Journal Articles:

No journal articles submitted with this report: View all 8 publications for this project

Supplemental Keywords:

multimedia, herbicides, insecticides, age dependent response, age-related differences, air pollution, assessment of exposure, biomedical research, body burden, children, children’s vulnerablity, cumulative exposure, cumulative pesticide exposure, dermal contact, dermal exposure reduction model, dietary exposure, environmental hazard exposures, exposure, exposure assessment, exposure pathways, health effects, human exposure, human health, human health risk, insecticides, long-term exposure, long-term exposure, multi-pathway study, pesticide exposure, pesticide residues, sensitive populations,, Health, RFA, Scientific Discipline, ENVIRONMENTAL MANAGEMENT, Toxics, Susceptibility/Sensitive Population/Genetic Susceptibility, Health Risk Assessment, pesticides, Risk Assessments, genetic susceptability, Environmental Chemistry, Molecular Biology/Genetics, Children's Health, Disease & Cumulative Effects, Risk Assessment, dietary exposure, health effects, Human Health Risk Assessment, sensitive populations, human health, urban air, environmental hazard exposures, cumulative exposure, age dependent response, dermal exposure reduction model, age-related differences, human exposure, pesticide exposure, long term exposure, body burden, dermal contact, insecticides, pesticide residues, children, exposure, biomedical research, multi-pathway study, children's vulnerablity, cumulative pesticide exposure, air pollution, human health risk, assessment of exposure, exposure assessment, exposure pathways

Progress and Final Reports:

Original Abstract

2002 Progress Report

2003 Progress Report

2004 Progress Report

Final