Insoluble Jarosite Immobilization Technology for Lead and Arsenic Co-Contaminated Soils
Kirk Scheckel (NRMRL, PI), Ranju Karna (NRMRL ORISE fellow), Matt Noerpel (NRMRL ORISE fellow), Karen Bradham (NERL), David Thomas (NHEERL), and Todd Luxton (NRMRL)
Summary: Recently, ORD received soil samples from Region 8. Despite the elevated level of lead (Pb) in the samples, blood lead levels (BLL) and bioaccessibility were incredibly low. ORD investigation of the soils identified plumbojarosite (PbFe3+6(OH)12(AsO4SO4)4) as the principle Pb species, which demonstrates extremely low solubility. ORD started preliminary testing to investigate if plumbojarosite formation can be induced from other lead phases as a means to immobilize soil Pb. The results show remarkable promise that soil contaminated with lead can be transformed to plumbojarosite to reduce bioavailability and reduce the need for costly soil removal.
In vivo Bioremediation of PFAS in Zebrafish
Tamara Tal (NHEERL, PI), Mark Maddaloni (Region 2), Erin Hines (NCEA), Adam Swank (NHEERL), and Mark Strynar (NERL)
Summary: U.S. citizens are ubiquitously exposed to Per- and Polyfluorylalkyl Substances (PFAS) and these exposures have been associated with hypercholesterolemia, cancer and developmental effects including developmental neurotoxicity. In select communities in Region 2, the recorded PFOA concentrations in blood serum are higher than mean CDC National Health and Nutrition Examination Survey (NHANES) concentrations, which assess the health and nutritional status of adults and children in the United States including determining levels of select chemicals in blood and urine. The recorded mean serum PFOA concentrations are roughly 60 µg/L in areas surrounding the Hoosick Falls Superfund Site. In Newberg, NY, mean human PFOS levels are approximately 20 µg/L. These are 30 and 4 times higher than PFOA and PFOS serum levels reported in the NHANES survey, respectively. The body burden of PFAS like PFOA and PFOS are markedly influenced by their half-lives (3-5 years in humans). In addition to preventing future exposure to toxic PFAS, methods are needed to reduce the amount of time the chemical stays in the body in affected individuals living in contaminated regions. Cholestyramine is a common and well-tolerated drug used to treat high cholesterol. It is hypothesized that cholestyramine, an anion-exchange resin, may promote the binding of PFAS in the gut and aid in its elimination via feces. Limited evidence suggests that cholestyramine may reduce serum PFAS levels in humans and rats (1-3). This PIP proposal will determine whether cholestyramine can reduce PFAS tissue concentrations and reverse related neurotoxicity outcomes in zebrafish exposed to PFAS compounds commonly detected in humans.
How Does Flooding Impact Superfund Sites Now and in the Future?
Chunling Tang (NERL, co-PI), Pai-Yei Whung (NERL, co-PI), and Valeria Garcia (NERL, co-PI)
Summary: Superfund sites represent some of the most contaminated environments in the US and typically require long-term cleanup lasting decades. Out of 1330 Superfund sites in the US, over three hundred are in danger of flooding, potentially placing millions of Americans living near these sites at additional risk. In recent years, the frequency and severity of extreme flooding has increased, and over 50% of historical extreme floods have occurred outside of FEMA-designated flood zones. In this project, we will evaluate the effect and risk of flooding at Superfund sites vulnerable to flooding beyond what has previously been done by FEMA and other institutions. Our capability to dynamically model extreme flooding events will fill-in needed information on the extent of extreme floods, the volume and velocity of water flow, the frequency and duration of the floods, and impacted communities that live within and outside of associated flood plains. The data and maps delivered as part of this project will provide key screening level information to communities, developers, local governments, and other potential site users that was not previously available.
Bypassing the Brain Barriers: Serum microRNAs as Biomarkers of Developmental Neurotoxicity
Mary Gilbert (NHEERL, PI) and Katherine O’Shaughnessy (NHEERL ORISE fellow)
Summary: Evaluating the neurodevelopmental effects of thyroid disrupting chemicals (TDCs, e.g., flame retardants, perfluorinated compounds, pesticides) is challenging. While current regulatory tests attempt to identify how TDCs may affect the developing rodent brain, these tests are costly, time consuming, and lack a simple brain-based metric of developmental neurotoxicity (DNT). Additionally, how do we accurately monitor the health effects of TDCs in humans? In address these challenges, we hypothesize that serum microRNAs will be reflective of DNT, and these molecular biomarkers can serve as a direct readout of an adverse chemical effect in rats and humans. Identification of such serum biomarkers can be used to (i) strengthen current regulatory testing in rodents, and (ii) monitor the health effects of TDCs in children by a rapid, noninvasive method (Figure 1).
Process Intensified Method for the Removal of Perfluorinated Compounds (PFCs) from Source Waters
Michael Gonzalez (NRMRL, PI)
Summary: Perfluorinated compounds (PFCs) have been employed for the past 60 years in numerous consumer products and industrial formulations. Their unique physicochemical properties offer high chemical and thermal stability and olephobic–hydrophobic properties, which offer advantages in product formulation. However, PFCs are bio-accumulative, resistant to oxidation, and are inert to many chemical and biological degradation pathways. As such, they are identified as an emerging contaminant of concern. The chemical inertness of PFCs is attributed to the high C-F bond strength (∼413 kJ mol−1 for the C-F bond in F3C-CF3). In this project, we will develop and design a continuous flow degradation process for PFC removal from source waters by utilizing an in-situ generated high shear force coupled with oxidation strategies.
Rapid Detection of Somatic Coliphage in Water
Michael Ware (NERL, co-PI), Jerry Stelma (NERL, co-PI), and Al DuFour (NERL, co-PI)
Summary: Viruses are a major cause of waterborne disease and are more persistent than bacterial indicators (E. coli). Their detection is a critical need in risk assessment. EPA Method 1615 detects viral pathogens but is very expensive and not rapid. Non-pathogenic somatic coliphages have been used a surrogate for viral pathogens and are they are easily detected by EPA Methods 1601 and 1602, but both methods require overnight incubations to form plaques in a bacterial lawn. This proposal will further optimize and refine a test assay developed in house which provides a somatic coliphage Most Probable Number (MPN) in ≤3 hours. This test assay is based upon the release of E. coli enzymes after lysis by somatic coliphage and is inexpensive, easy to perform, and requires no expensive laboratory equipment. If this method proves to be robust and the MPN results correlate with plaque and bacterial indicator results, then a rapid test assay would be available to indicate viral exposure risk prior going to the beach.
Using Encrypted Confidential Business Information to Build Toxicological Models
Grace Patlewicz (NCCT, PI), Prachi Pradeep (NCCT ORISE fellow), and Jeremy Fitzpatrick (NCCT)
Summary: Approximately 40,000 of the substances listed on the current TSCA inventory have associated confidential business information (CBI). The associated CBI ranges from physical chemical properties to animal test results for a number of different toxicological endpoints. Currently access to this data is possible but extremely restricted, making it difficult even for researchers within EPA to use. We propose using recently developed techniques in homomorphic encryption to allow greater access to the data for in silico toxicological model development. Homomorphic encryption (HE) is a privacy preserving method which allows for transforming raw data into an encrypted format that can be used for computational model development without compromising the CBI. The HE data can be used to develop predictive models using suitable machine learning techniques in such a way that the encrypted predictions can be decrypted to provide the same result as a model developed on original unencrypted data (CBI). Such an effort will allow easy access to CBI for further research and innovation in science.
Treatment of PFOA using an innovative technology of UV-vis/Zn0.8Cu0.2Fe2O4/Oxalic Acid
Mallikarjuna Nadagouda (NRMRL, co-PI) and Endalkachew Sahle-Demessie (NRMRL, co-PI)
Summary: Our approach is to modify iron oxide particles with MnO2, Cu, and Ag, so that the media can oxidize As (III) to As(V) in drinking water treatment systems, simultaneously adsorb arsenic, and eliminate bacterial growth on the media.