About EPA

About the National Exposure Research Laboratory (NERL)

What We Do

EPA’s National Exposure Research Laboratory (NERL) supports EPA’s mission to protect human health and the environment by developing and applying innovations in exposure science. Exposure science sets the context for understanding and solving real-world problems, and is used to help answer three fundamental questions:

  • Is there a risk?
  • If so, how do we reduce/mitigate/prevent the risk?
  • Have our actions been successful in reducing risk?

Headquartered in Research Triangle Park (RTP), N.C., NERL has an in-house workforce of more than 310 scientists, engineers and staff across three divisions in four locations: RTP, North Carolina; Cincinnati, Ohio; Athens, Georgia; and Las Vegas, Nevada.

NERL is internationally recognized as the leader in environmental exposure science. Our multidisciplinary expertise enables the laboratory to bring cutting-edge research and technology to the field of exposure science to address the Agency’s priority environmental problems.

NERL’s Niches

Below are NERL’s scientific capabilities (i.e., our niches):

  • Analytical/Monitoring Methods Development: Research conducted in either the laboratory or field that is used to develop, refine or evaluate tools to quantify, measure, or sample stressors in the environment or in receptors.
  • Indicators/Indices of Exposure: Research conducted to determine how to combine measurements, data and/or models in a way that succinctly describes or characterizes the state or change of exposure.
  • Exposure/Dose Process Characterization: Research including field and laboratory studies and data analysis conducted to better understand and gain knowledge about fate and transport, exposure and dose in real world instances. This research is primarily hypothesis driven, and includes collection of data to elucidate the important processes in models, inputs to models, and data to evaluate models. This research is applied to both human and ecological systems.
  • Decision Support Tools: Research activities to assemble data, analytical and predictive tools and knowledge into a useable format for analysts and decision makers.
  • Predictive Modeling: Research to develop, evaluate, and apply first principle, statistical, or stochastic models. This includes models for environmental characterization, personal exposure and dose, and mechanistic elucidation but does not include source apportionment models.
  • Source Apportionment/Environmental Forensics: Research where source apportionment or environmental forensics tools are developed and applied in real world instances to identify important sources and pathways for exposure.

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Location:Research Triangle Park, N.C.; Cincinnati, Ohio; Athens, Ga.; Las Vegas, Nev.

Director:Jennifer Orme-Zavaleta, Ph.D.

Deputy Director: Timothy Watkins

  • Phone: 919-541-2106

Organization chart

NERL is anchored by three science divisions:

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Exposure Methods & Measurement Division (EMMD)

Director: Timothy Buckley; Research Triangle Park, North Carolina

Phone: 919-541-2454

EMMD provides the science that underlies the measurement of environmental stressors and their interaction with biological systems. This science includes method development, evaluation, and field and laboratory testing. These measurement methods are foundational to the Agency’s regulatory programs and stakeholder needs in protecting public health and the environment. EMMD scientists:

  • Develop methods for measuring stressors (positive or negative) in environmental and biological media
    • Stressors include chemical, biological, physical, and psychosocial
  • Design and conduct measurement-based studies (field and laboratory) to identify sources (forensics), inform fate and transport processes, and estimate exposure and dose for ecological and human receptors
  • Are critical collaborators in providing measurements for:
    • Exposure classification in epidemiologic studies
    • Exposure in the context of risk assessment
    • Dose estimation for environmentally relevant toxicological studies
    • EPA Program and Regional Offices, who serve public and stakeholder needs

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Computational Exposure Division (CED)

Position Opening: Director, Computational Exposure Division

Deputy Director: Gerald Brunson; Athens, Georgia

Phone: 706-355-8005

CED develops & evaluations data, decision-support tools & models to be applied to media-specific or receptor-specific problem areas. Scientists use modeling-based approaches to characterize exposures, evaluate fate & transport, & support environmental diagnostics/forensics with input from multiple data sources. CED scientists:

  • Develop modeling tools needed to support implementation of the Clean Air, Clean Water, Safe Drinking Water, & Endangered Species Acts;
  • Evaluate the accuracy & reliability of modeling tools that characterize changes in meteorology, air quality, pollutant deposition, and watershed biogeochemistry, as well as ecological and human exposures in response to changes in land use and climate change;
  • Support environmental diagnostics & forensics with input from multiple data sources;
  • Develop receptor-specific models, process models & decision support tools; and
  • Develop, apply & evaluate models that estimate human exposure to environmental contaminants & the resulting internal dose.

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Systems Exposure Division (SED)

Director: Jay Garland; Cincinnati, Ohio

Phone:  513-569-7334

SED integrates exposure data, tools, methods & models to assess cumulative exposures to humans and ecosystems. This assessment uses systems-based approaches to organize current knowledge, simulate potential futures & synthesize results. SED translates information into decision-making frameworks that integrate human & ecological, multimedia, socio-economic & cumulative risk considerations to improve human well-being and the sustainability of the built and natural environment. The holistic view on exposure science and its linkage to sustainable solutions emphasizes cross-divisional and laboratory integration. SED scientists:

  • Incorporate exposure science data into broader sustainability assessment tools to inform decisions that can mitigate or prevent adverse health & ecological impacts;
  • Measure & model ecological exposures at various scales to describe & mitigate adverse impacts on key ecosystem components & processes;
  • Address ecological exposure questions & systems management problems influenced by human-driven factors like climate change & landscape modification;
  • Design tools & approaches to simulate the dynamics of natural systems & built infrastructure in future scenarios; and
  • Address modeling problems that cross media, involve interacting exposure pathways, or affect multiple receptors

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