Superfund Research Program
The NIEHS Superfund Research Program (SRP) hosted a seminar series that highlighted innovative analytical tools and methods developed and used by SRP grantees. The presenters featured the benefits of these new tools and methods compared to conventional methods. They also included information about how the technology has helped to facilitate ongoing SRP research.
We would like to thank the following members of the Risk e-Learning committee for their help in developing the "Analytical Tools and Methods" Risk e-Learning sessions: Michael Adam, Felicia Barnett, Steve Dyment, and John McKernan.
Session I - Field-Ready Biosensors to Assess Bioavailability and Toxicity
April 17, 2017 • 1:00 – 3:00 p.m. EDT
To view the archive, visit EPA's CLU-IN Training & Events webpage.
Treatment assessments and water quality monitoring that rely only on measuring the reduction of target contaminant concentrations are often insufficient because they do not consider the complex and broader risks that specific contaminants or mixtures and their transformation products pose to the environment and human health. Researchers described their tools to assess bioavailability/toxicity for more effective human and/or environmental monitoring.
Presenters:
- Michael Unger, Ph.D., Virginia Institute of Marine Science
- April Gu, Ph.D., Northeastern University SRP Center
- Natalia Vasylieva, Ph.D., and Bogdan Barnych, Ph.D., University of California, Davis SRP Center
Moderator:
- Stephen Dyment, U.S. Environmental Protection Agency
Michael Unger, Ph.D., Professor of Marine Science at the Virginia Institute of Marine Science, discussed his work on advances in biosensor technology that allows near real-time measurement of contaminants at sub parts-per-billion (ppb) concentrations in small volume (< 5 mL) aqueous samples. Polycyclic aromatic hydrocarbon (PAH) concentrations can be measured in the field within minutes after collection to map the spatial distribution of PAHs at contaminated sites and to assess the bioavailable or toxic fraction within sediments. Correlations between PAH concentrations measured by the biosensor and those measured by gas chromatography - mass spectrometry (GC-MS) were excellent, and the results are now being used to help evaluate sediment remediation strategies.
April Gu, Ph.D., Professor of Civil and Environmental Engineering at the Northeastern University SRP Center, discussed her work to develop a novel, feasible, and cost-effective quantitative toxicogenomics-based toxicity assessment platform for high-throughput and effective chemical hazardous identification and environmental toxicity monitoring. Gu also described how she and her team systematically optimized the assay platform, evaluated its robustness and performance, validated the assay output, and demonstrated its wide applications.
Natalia Vasylieva, Ph.D., and Bogdan Barnych, Ph.D., postdoctoral researchers at the University of California (UC) Davis SRP Center, discussed how they choose target analytes for immunoassay analysis. They also introduced nanobodies as novel and exciting reagents for immunoassay-based biosensors. The second part of the presentation focused on examples of immunoassay application for human and environmental monitoring, as well as their application in biosensors.
Session II - Techniques for Trace Analysis of Metals and Chemical Mixtures
May 22, 2017 • 1:00 - 3:00 p.m. EDT
To view the archive, visit EPA's CLU-IN Training & Events webpage.
During the second session of the series, speakers highlighted practical techniques to measure trace levels of potentially harmful materials including metals, PAHs, antimicrobials, flame retardants, and other chemical mixtures. They showed how techniques such as Elemental Mapping, Accelerator Mass Spectrometry, and High Resolution Mass Spectrometry can be used to better characterize our environment and quantify body burden.
Presenters:
- Tracy Punshon, Ph.D., Dartmouth College SRP Center
- Bruce Buchholz, Ph.D., Lawrence Livermore National Laboratory
- Lee Ferguson, Ph.D., Duke University SRP Center
Moderator:
- John McKernan, U.S. Environmental Protection Agency
Tracy Punshon, Ph.D., a research assistant professor at the Dartmouth College SRP Center, introduced and translated the technology of elemental mapping, or spatially resolved elemental analysis. She provided several examples of the instruments used to collect elemental maps, showed examples of how the technique is being applied in the biological and environmental sciences, and provided information on accessibility and support for those interested in using it in their research.
Bruce Buchholz, Ph.D., a research scientist at the Lawrence Livermore National Laboratory and member of the UC Davis SRP Center, described Accelerator Mass Spectrometry (AMS), a technique for measuring zeptomole to femtomole quantities of carbon-14 in sub milligram sized samples. The technique is used to quantify metabolism of chemicals at relevant exposures in animals and humans, such as dermal exposure to pesticides and ingestion of PAHs or antimicrobials. The metabolism studies have become more streamlined recently with the addition of an integrated HPLC-AMS-MS system and can identify dominant metabolites at relevant doses from which specific field assays can be developed without the use of the carbon-14 label. All tissues, blood, urine, saliva, or purified biomolecules (protein, DNA, RNA) are amenable to AMS analyses.
Lee Ferguson, Ph.D., an associate professor at the Duke University SRP Center, discussed high resolution mass spectrometry, which has advanced as a powerful tool for identification of targeted and non-targeted organic pollutants in complex mixtures. He highlighted applications of these technologies to assess human and ecological exposure to environmental pollutants associated with consumer products, indoor environments, and aquatic systems. Specific strategies and workflows for prioritization and structural identification of emerging contaminants were highlighted, and case studies were presented for pollutants in house dust, children's hand wipes, and wastewater-impacted environments.
Session III - Fate and Transport of Contaminants
June 12, 2017 • 1:00 - 3:00 p.m. EDT
To view the archive, visit EPA's CLU-IN Training & Events webpage.
During the third session of the series, speakers highlighted tools and methods to detect contaminants and measure their fate and transport in the environment. The speakers highlighted work related to polychlorinated biphenyls (PCBs), per- and polyfluoroalkyl substances (PFASs), chlorinated solvents, and other chemicals in the environment.
Presenters:
- Keri Hornbuckle, Ph.D., University of Iowa SRP Center
- Jennifer Guelfo, Ph.D., Brown University SRP Center
- Mark Brusseau, Ph.D., University of Arizona SRP Center
Moderator:
- Felicia Barnett, U.S. Environmental Protection Agency
Keri Hornbuckle, Ph.D., professor of civil and environmental engineering at the University of Iowa SRP Center, discussed advances in the measurement of PCBs in complex environmental matrices. Her laboratory developed methods for reproducible, accurate, and precise measurements of all 209 PCB congeners at sub-ppb levels in indoor and ambient air, water, soils, sediments, pore waters, plant tissues, and human blood serum. She discussed methods for sampling, pressurized solid extraction, automated concentration and purification, detection using triple quadrupole mass spectrometry, and quality control and assurance methods that deliver whole method quantification limits less than 1 ng of total PCBs /sample.
Jennifer Guelfo, Ph.D., a postdoctoral researcher and State Agencies Liaison at the Brown University SRP Center, provided background related to PFASs and discussed key challenges and knowledge gaps related to fate and transport. She also presented an overview of PFAS occurrence in large-scale drinking water systems across the United States using data from EPA's unregulated contaminant monitoring rule (UCMR)-3 collection effort. Lastly, she introduced a collaborative effort between the Brown SRP and state regulators that is targeted at providing a user-friendly geospatial framework for identification of potential PFAS source zones.
Mark Brusseau, Ph.D., professor in the School of Earth and Environmental Sciences at the University of Arizona SRP Center, described the Integrated Contaminant Elution and Tracer (ICET) test for improved characterization of mass transfer, attenuation, and mass removal. Extensive and persistent groundwater contaminant plumes are widespread at sites contaminated by compounds such as chlorinated solvents, 1,4-dioxane, Methyl Tertiary Butyl Ether, and perfluorinated chemicals. Improved characterization methods are needed to delineate and quantify the processes and factors that contribute to plume persistence. This presentation summarized the ICET test, with illustrative applications for characterizing constraints to mass removal.
to Top