Impact/Purpose:

The primary study objectives are:

1) Develop and validate tools such as the spray booth and environmental chambers for use in ongoing fate and transport studies.

2) Provide measurements (air and surface concentrations) for select residential use pesticides to evaluate their translocation following an application in the U.S. EPA Indoor Air Quality Research House.

3) Develop a fundamental background for further research aimed at understanding more complex interactions such as fate and behavior of pesticide mixtures based on physical and chemical properties following applications in the residential environment, as well as the potential for human exposure associated with pesticide mixtures.

Description:

The Food Quality Protection Act (FQPA) of 1996 mandates consideration of aggregate exposures from food and non-occupational sources as part of EPA's pesticide evaluation process. In its implementation plan, EPA states that "EPA must develop new data and exposure models to estimate specific pesticide exposures from non-food sources" in order to rigorously consider aggregate exposure. Since many people spend close to 90% of their time indoors, it is especially important to understand non-food and non-occupational exposures that occur in the indoor environment.

The potential for indoor exposures to pesticides can't be fully understood without clarification of the behavior of pesticides applied indoors. This includes understanding of: the sources and sinks for pesticides indoors, the penetration of pesticides from the outdoors into the indoors, the transport of pesticides indoors, the partitioning of pesticides between air, indoor dust and surfaces, and their degradation. The proposed research is designed to provide the data inputs to develop models to understand the behavior of pesticides indoors based on their physical and chemical properties, inert constituents of the formulation, and the type of application.

As part of this task, special tools are under development. A spray deposition booth designed to apply pesticide deposits and residues onto surfaces is currently under evaluation. This device will allow different pesticides and formulations to be applied to common residential surfaces in order to establish decay rates, partitioning, and emissions factors. The system will also be used to generate treated surfaces that can be used to evaluate surface wipe methods commonly employed in field measurement studies. A second tool under development is the small environmental chamber method for studying pesticide fate and transport. Chambers will be used to hold the treated surfaces to determine decay rates and emissions from different surfaces for residential use pesticides. In addition to the small chamber tests, a study will be conducted in the U.S. EPA Indoor Air Quality Research House to examine the spatial and temporal distribution of multiple current-use residential insecticides in air and on surfaces within the house.

Research findings will ultimately be incorporated into an indoor environment model for the analysis of indoor exposure to pesticides (such as SHEDS).

Record Details:

Record Type:PROJECT

Start Date:10/01/2003

Projected Completion Date:09/01/2006

Record ID: 56115

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Project Information:

Progress :FY03

A workshop was held to discuss human exposure models, data required as inputs to the models, and potential study designs to collect data needed for the models. As a result of the workshop it was determined that the first phase of work on this task should be tests examining the feasibility of using environmental chambers and the development of standard sources for select pesticides were required.

FY04

-Instrumentation, including a gas chromatograph/mass spectrometer (GC/MS) and liquid chromatograph/MS/MS (LC/MS/MS), were acquired and the essential laboratory modifications were performed to carry out the chemical analysis required under this task. Analytical methods were developed for the insecticides diazinon, chlorpyrifos, cyfluthrin and permethrin and methods for selected matrices were examined in preparation for the in-house laboratory chemical analysis of all samples generated under this task.

-A pesticide deposition spray booth has been developed to homogeneously place pesticide deposits and residues onto substrates representing common residential surfaces. The spray booth has undergone rudimentary evaluation using water applied to filter dishes to gravimetrically define operating parameters.

-A work plan and quality assurance project plan (QAPP) for the experimental work to be conducted in collaboration with NRMRL and their in-house contractor (ARCADIS) were developed.

Relevance :Work to be performed under this task will directly support the NERL human exposure measurements program by developing sampling and analysis methods for emerging pesticides and current use residential pesticides and by developing a fundamental background for understanding more complex interactions of pesticide mixtures in the residential environment. Specifically this task will utilize and extend particle deposition methodology developed by Sharon Harper in MDAB under the task 9577 to include pesticides. The work directly links to Task 7040, "Longitudinal Study of Young Children's Exposures in their Homes to Selected Pesticides, Phthalates, Brominated Flame Retardants, and Perfluorinated Chemicals (A Children's Environmental Exposure Research Study - CHEERS)" by improving base knowledge on the distribution of pesticides following applications in residences and task 15651 "Method Development, Evaluation, Refinement, and Analysis for Field Studies and Development of LC/MS/MS Methods for Current-use and Emerging Pesticides and Other Environmental Contaminants." Data generated from the field measurement studies will be used both as inputs and for the evaluation of multimedia, multi-pathway human exposure models that are currently under development as described under Task 3948 for SHEDS models (Valerie Zartarian, Ed Furtaw and Debbie Bennett). The outputs of this task are linked with the core human exposure research being conducted in NERL and will contribute to the collection and analysis of samples for aggregate exposure assessments for children. The results of studies performed under this task contribute to the goals of the Office of Pesticide Programs and the pesticide registrants by providing data that can be used to upgrade the risk assessment procedures and reduce uncertainties pertaining to cumulative and aggregate risk. Findings will be delivered to clients as QA/QC reviewed data packages and published as proceedings and journal articles in peer reviewed forums.

Clients :EPA: NERL (MDAB: Sharon Harper; Mark Stryner), (Ed Furtaw), (EMRB: Valerie Zartarian), NRMRL (Mark Mason, Zhishi Guo) , OPP (Jeffery Evans), EPA NCEA (Jackie Moya), Scientific Community

Project IDs:

ID Code :15565

Project type :OMIS