Biography: Linda S. Lee is a Purdue University Professor in the Department of Agronomy; Program Head for the Ecological Sciences & Engineering Interdisciplinary Graduate Program; and Courtesy Faculty in Environmental Ecological Engineering. She joined the Purdue faculty in 1993 with degrees in chemistry (BS), environmental engineering (MS), and soil chemistry/contaminant hydrology (PhD) from the University of Florida. Her group researches environmental fate processes and contaminant remediation in various media for use in mitigating contamination and management decision tools in industrial and agricultural settings. She is well-published in top-tier environmental journals and has served on national and international advisory groups addressing water quality issues, fair land-applied biosolid policies, and predicting chemical risk. Her research over the past 15 years has focused primarily on poly-and perfluoroalkyl substances and organic endocrine-disrupting chemicals of emerging concern.
PFAS Characteristics, Fate and Challenges in Waste Management
Abstract: Per/polyfluoroalkyl substances (PFAS) have been widely used in commercial and industrial products with the number of different compounds identified as PFAS approaching 5000. Those most frequently monitored and studied include several perfluoroalkyl acids (PFAAs), which have been found coming from multiple sources are being found in groundwater, surface water, and potable waters. PFAS sources leading to water contamination range from fire-fighting activities, industrial spills and dumping, leaky landfills, wastewater effluent discharge, land-applied biosolids, and storm runoff. The increased awareness of potential adverse effects of PFAS and their frequent occurrence in water resources and biota have prompted state and federal agencies to re-examine PFAS risk assessments and establish aggressive health advisory levels. Concerns of PFAS contributions from land-applied biosolids are leading some states to limit the land application of biosolids and composts to only those meeting a set of PFAS screening levels and others to consider completely banning the practice, which is also problematic. Many PFAAs are terminal products of microbial degradation of precursor PFAS present in commercial products and wastewater influent; therefore, limiting mitigation or reduction of PFAS in the water and wastewater treatment process to abiotic technologies.PFAS occurrence in and leachability from biosolids-based and municipal compost-based soil amendments will be presented along with the challenges in estimating actual PFAS loads in waste-based materials and waste management and potential PFAS mitigation and treatment options.
Biography: Daniel L. Villeneuve is a research toxicologist with the United States Environmental Protection Agency’s Office of Research and Development (ORD). He received a BS in Water Resources and Zoology from the University of Wisconsin-Stevens Point and a Ph.D. in Zoology and Environmental Toxicology from Michigan State University. He has over 20 years of experience conducting freshwater ecotoxicology research. His present research is focused on the use of new approach methods to characterize and evaluate hazards organic contaminants pose to fish and wildlife. This has included the use of biological effects-based tools to monitor contaminants of emerging concern in the Great Lakes and other freshwater systems. Dr. Villeneuve has published over 180 peer-reviewed papers in the field of ecotoxicology and his work has been recognized with over 20 US EPA Scientific and Technical Achievement awards.
Risk-based Screening of Emerging Contaminants in the Great Lakes Basin
Abstract: With steady advances in analytical chemistry methods and instrumentation, increasing numbers of chemicals associated with human activities are being detected in the environment. The ability to discriminate safe from hazardous concentrations of those chemicals relies on the availability of regulatory benchmark concentrations and/or toxicity data for individual chemicals. However, conventional animal toxicity testing has not kept pace with the manufacture of new chemicals and their subsequent release and detection in the environment. Dr. Villeneuve will provide an overview of a 10-year, multi-agency research effort focused on surveillance and monitoring of emerging contaminants in the Great Lakes. As part of the research, contaminant concentrations detected in surface water and other media were compared with both traditional toxicity benchmarks and data from new approach methodologies (NAMs) to provide triage with respect to potential for adverse effects on Great Lakes ecosystems. Additionally, strategies for considering the cumulative impacts of mixtures of contaminants for site prioritization and/or site-based assessments will also be discussed. While no “smoking guns” associating adverse ecological impacts with contaminant occurrence were revealed, the research illustrates how multiple lines of evidence helped to identify contaminants, sites, or hazards of greatest concern and inform efficient use of available monitoring and management resources. The data and approaches developed inform ongoing research and monitoring in the Great Lakes basin and can be applied to other systems as well.