Grantee Research Project Results
2003 Progress Report: Saliva Bio-monitoring for Organophosphorus Pesticide Exposures in Children
EPA Grant Number: R828606Title: Saliva Bio-monitoring for Organophosphorus Pesticide Exposures in Children
Investigators: Fenske, Richard , Lu, Chun
Current Investigators: Fenske, Richard , Barr, Dana Boyd , Lu, Chensheng (Alex) , Rodriguez, Teresa
Institution: University of Washington
Current Institution: University of Washington , Centers for Disease Control and Prevention , Emory University , Universidad Nacional Autónoma de Nicaragua–León
EPA Project Officer: Hahn, Intaek
Project Period: September 1, 2000 through August 31, 2003 (Extended to August 31, 2005)
Project Period Covered by this Report: September 1, 2002 through August 31, 2003
Project Amount: $742,597
RFA: Biomarkers for the Assessment of Exposure and Toxicity in Children (2000) RFA Text | Recipients Lists
Research Category: Children's Health , Human Health
Objective:
The primary objective of this research project is to evaluate the feasibility of quantifying children's exposure to organophosphorus (OP) pesticides through saliva biomonitoring. This work is part of an ongoing effort to improve exposure assessment methods for children. Two OP pesticides—chlorpyrifos and diazinon—were proposed for use in this research project. These compounds are used widely in both agricultural and residential environments, and the resulting aggregate exposures for children are complex and therefore amenable to biological monitoring.
The specific objectives of this research project are to: (1) determine the pharmacokinetics of these pesticides in saliva and plasma in animals following dermal and oral dosing at variable exposure levels and salivary flow rates; (2) characterize the relationship of pesticide concentrations in saliva and plasma in animals, and evaluate the sensitivity and specificity of salivary excretion for these two compounds at low doses; (3) modify and validate enzyme linked immunosorbent assay methods for analyzing chlorpyrifos and diazinon in biological samples; (4) measure children's exposures to chlorpyrifos and diazinon in saliva and urine following the application of these compounds in nearby orchards or within residences; (5) develop a pharmacokinetic model for these pesticides in children using salivary and urinary measurements; and (6) compare total absorbed dose estimates for chlorpyrifos and diazinon in children using salivary measures of parent compounds, urinary dialkylphosphate metabolite measurements, and compound-specific urinary metabolite data.
Progress Summary:
We have finished the animal study component of this research project. Part of the diazinon data has been written into a manuscript, which was published at the end of 2003 (Lu, et al., 2003). Samples from chlorpryifos and permethrine studies are being analyzed at the University of Washington laboratory. We will have the results at the end of April 2004. Data will be analyzed using SAAM II for pharmacokinetic analysis, and will be written into a manuscript in June 2004.
We have completed the field study in Leon, Nicaragua, a major accomplishment in 2003. All of the specimen samples were shipped back to the University of Washington laboratory in October 2003. A total of 17 families (one adult and one child from each family) participated in this study. Farmers either sprayed diazinon in a banana plantation or chlorpyrifos in a corn field. Multiple daily urine, venous blood, and saliva samples were collected from adults, whereas only urine and saliva samples were collected from children. Both blood and saliva samples are being analyzed for chlorpyrifos and diazinon, and urine samples are being analyzed at the Centers for Disease Control and Prevention's National Center for Environmental Health. The collaboration with faculty and scientists at the National Autonomous University of Nicaragua was very successful, and more collaboration is anticipated in the future.
Future Activities:
We will continue to analyze the remaining samples collected from animal studies and human specimen samples from Nicaragua. Data from these studies will be analyzed using pharmacokinetic models. At least three manuscripts will be written based on the results.
On January 1, 2004, the State of Washington is launching a program in which farmers and farm workers who are in contact with OP pesticides for more than 40 hours per week are required to have their acetylcholinesterase activities monitored. In collaborating with the state in this program, we are proposing an add-on project in which farm workers' exposure also will be monitored using saliva biomonitoring. We have submitted a human subject application to the University of Washington Institutional Review Board for the approval of such activity. If the approval is granted, we anticipate conducting this study in May/June 2004.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
Other project views: | All 7 publications | 2 publications in selected types | All 2 journal articles |
---|
Type | Citation | ||
---|---|---|---|
|
Lu C, Irish R, Fenske R. Biological monitoring of diazinon exposure using saliva in an animal model. Journal of Toxicology and Environmental Health-Part A 2003;66(24):2315-2325. |
R828606 (2002) R828606 (2003) |
|
Supplemental Keywords:
toxic chemical, survey, epidemiology, health, toxics, children's health, health risk assessment, susceptibility, sensitive population, genetic susceptibility, pesticides, diazinon, air pollution, biological markers, children, children's vulnerability, chlorpyrifos, dermal contact, dietary exposure, environmental hazard exposures, exposure, exposure assessment, exposure pathways, infants, insecticides, organophosphorus pesticides, pesticide exposure, pesticide residues, saliva, biomarker, biomonitoring, permethrin, saliva, plasma, children., RFA, Health, Scientific Discipline, Toxics, Health Risk Assessment, Environmental Chemistry, pesticides, Susceptibility/Sensitive Population/Genetic Susceptibility, Biochemistry, Environmental Monitoring, Children's Health, genetic susceptability, pesticide exposure, sensitive populations, infants, dermal contact, chlorpyrifos, exposure, survey, air pollution, children, children's vulnerablity, insecticides, toxicity, pesticide residues, exposure pathways, saliva, biological markers, dietary exposure, exposure assessment, organophosphate pesticides, DiazinonRelevant Websites:
http://depts.washington.edu/pnash Exit Synthesis Report of Research from EPA’s Science to Achieve Results (STAR) Grant Program: Feasibility of Estimating Pesticide Exposure and Dose in Children Using Biological Measurements (PDF) (42 pp, 3.87 MB)
Progress and Final Reports:
Original AbstractThe 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.