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Assessing the risk of PFAS from land applied biosolids vs. other common exposure pathways


Oct 24, 2023





PFAS are a hot topic.  Learn more during this in-depth session!

In response to reports of potential or reported PFAS contamination, many communities across the country quickly implicate land-applied biosolids as the cause, often calling for outright prohibition. Whereas banning land application of biosolids may make people feel safer, the reality is that this action will, in practically all instances, have minimal impact on exposure to PFAS. Long standing regulations prohibit land application of biosolids near drinking water wells and other environmentally sensitive areas.

To provide some context, a recent study comparing PFAS in biosolids to other commonly available products was completed. PFAS concentrations in biosolids (50-250 parts per billion (ppb) were found to be many thousands of times lower than in food packaging materials (867,000 ppb); hundreds of times lower than in products like ketchup (58,000 ppb), organic tomato sauce (21,000 ppb), and cosmetics (10,500 ppb); and more than two times lower than the levels measured in common household dust (525 ppb).

Banning land application of biosolids would require utilities across the country to invest billions of dollars in infrastructure. The farming community will also be deprived by the loss of an affordable, renewable fertilizer source. Costs that will inevitably be passed onto the rate payer and consumer. With the understanding that land application bans will do little to reduce our day-to-day exposure to PFAS, communities need to fully appreciate the costs vs. benefits of such actions.

This presentation will examine these issues in more depth in an effort to inform people of the benefits of land applied biosolids vs. the consequences of ineffectual land application bans in the name of reducing PFAS exposure.


This informational webinar is presented in conjunction with the Mid-Atlantic Biosolids Association (MABA). 


This complimentary GoToWebinar session is scheduled to begin promptly at 12 noon, eastern time, on Tuesday, October 24.  Registrants must have both a computer and audio/phone in order to participate.

A confirmation with log in instructions will be emailed to each registrant immediately upon registering and a reminder email will be sent one day and one hour prior to the session.

Register here





October 24, 2023
12:00 pm - 1:00 pm
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Pennsylvania NewsMedia Association Foundation



William “Bill” Toffey, Effluential Synergies, LLC

Bill has 40 years’ experience in municipal wastewater, environmental and energy management.   He is the principal of Effluential Synergies LLC, a sustainable residuals consultancy, and for a decade through to 2021 served as Executive Director of the Mid Atlantic Biosolids Association. For 20 years prior to this position, he managed biosolids operations for the Philadelphia Water Department. During his career he has authored over 70 papers and presentations to a range of local, national, and international technical audiences, including operator training manuals and programs. He also authored 120 monthly biosolids technical reports to MABA members. Bill graduated from the College of Agriculture and Life Sciences at Cornell University and has a Masters of Regional Planning degree from the University of Pennsylvania. He is active in national and international professional organizations.

Erica McKenzie, PhD, Associate Professor in the Department of Civil and Environmental Engineering at Temple University

Dr. Erica McKenzie, Associate Professor in the Department of Civil and Environmental Engineering at Temple University (Philadelphia, PA), studies chemical contaminant fate and transport in natural and engineered systems.  Dr. McKenzie has been conducting research on PFAS for more than 10 years, with PFAS projects spanning removal and degradation-based treatments, uptake into foodwebs, and sorption/desorption from solids.  The McKenzie research group has investigated PFAS in sewage solids to assess factors that impact sorption capacity and approaches to immobilize PFAS in biosolids.

Ian Pepper, Professor of Environmental Microbiology, University of Arizona

Dr. Pepper is a Regents Professor at the University of Arizona, where he has taught and conducted research since 1977.  He is also Director of the University of Arizona Water & Environmental Technology Center (WET), and Director of the Water and Energy Sustainable Technology Center known as WEST. Dr. Pepper is an environmental microbiologist whose research has focused on soil land water quality and land application of biosolids. His expertise has been recognized by membership on 6 National Academy of Science Committees. Dr. Pepper is a Fellow of the American Association for the Advancement of Science, the American Academy of Microbiology, the Soil Science Society of America, and the American Society of Agronomy. He is also a Board Certified Environmental Scientist within the American Academy of Environmental Engineers and Scientists. He is the author or co-author of nine textbooks; 40 book chapters; and over 240 peer-review journal articles.

Malcolm Taylor, PhD, PE, Washington Suburban Sanitary Commission

Dr. Malcolm Taylor is a principal Environmental Engineer with the Washington Suburban Sanitary Commission with over 25 years of experience in the water & wastewater industry. His work focuses on optimization of advanced wastewater treatment processes and promoting the beneficial reuse of biosolids and water treatment residuals. Before coming to WSSC, Malcolm earned his PE as an engineering consultant and taught at Penn State University where he received his PhD in Agricultural and Biological Engineering. In his spare time Malcolm enjoys surfing, snowboarding, golf, and mountain biking.