IWRRC Logo

Factsheet – A survey of forever chemicals in Indiana: does agricultural biosolid application contaminate wetland ecosystems with per– and polyfluoroalkyl substances (PFAS)?

A research project funded by the Indiana Water Resources Research Center through the U.S. Geological Survey’s 104B annual base grants (section 104 of the Water Resources Research Act of 1984, as amended).

Start Date: 2021-09-01

End Date: 2022-08-31

Total Federal Funds: $25,000

Total Non-Federal Funds: $36,012

Per- and polyfluoroalkyl substances (PFAS) are a large class of chemicals that have been released into the environment, resulting in ubiquitous exposure, accumulation, and toxicity among humans and wildlife. PFAS concentrate in municipal biosolids, which are often recycled as agricultural fertilizer. Crops grown on these fields have been examined for PFAS uptake, and soil biota have been assessed for exposure and accumulation. However, no studies have examined wetland ecosystems receiving this runoff. We identified a permanent, constructed wetland receiving runoff from biosolid-amended fields and a reference site with no known biosolid source to collect samples to determine if and how biosolid amendments introduce PFAS into nearby wetland ecosystems.

Research Objectives

Determine whether agricultural biosolid applications in Indiana have led to PFAS contamination in adjacent wetland ecosystems by:

 

1. characterizing identities and concentrations of PFAS in biosolid amended soils and in receiving wetland water and sediments,

 

2. calculating bioaccumulation and biomagnification factors (BAFs and BMFs, respectively) for biota across trophic levels to determine if and how PFAS move through aquatic food webs, and

 

3. determining whether physiochemical properties like chain length, functional group identity, or sorption coefficients are associated with flux between biosolid affected soils and wetland media/biota. 

Bleeding largemouth bass for analysis
Largemouth bass being bled for PFAS analysis (above) and PIT tagged for long-term follow-up of PFAS concentrations (below).

Researcher Profile

Dr. Marisol Sepulveda

Principal Investigator Dr. Maria Sepulveda is a Professor and Associate Head of Research in the Department of Forestry & Natural Resources (FNR) at Purdue University.

Co-Principal Investigators:
Dr. Tyler Hoskins, Post-doctoral Research Associate, FNR,
Dr. Jason Hoverman, Professor of Vertebrate Ecology, FNR, and,
Dr. Linda Lee, Professor and Associate Head, Department of Agronomy.

Major Conclusions & Significance

  • A wide range of PFAS was detected in media and biota from both constructed wetlands studied.
  • Sources of PFAS to our ‘reference’ site are likely various and we will need to identify additional cleaner sites for upcoming field studies.
  • PFAS profiles in water and sediment were different to PFAS profiles from biota.
  • Predominance of precursors in media and terminal PFAS in biota strongly suggests transformation and metabolism. Microbes and multicellular biota likely metabolize precursors and intermediates at our sampling sites.
  • PFAS in tissues of largemouth bass and bluegill, fish commonly grown and eaten by Hoosiers, represents an additional route of PFAS exposure that needs to be taken into account when assessing health risks.

What Does This Mean For Indiana?

Results from our work are preliminary and more samples need to be analyzed in order to have a clearer picture on PFAS profiles and concentrations in fish and other organisms inhabiting constructed wetlands across Indiana. Our results are significant, because they will provide PFAS concentrations from fish of great commercial importance, which should help inform health risk assessments. Fish ponds are extremely common across our state, and many Hoosiers rely on them as a source of protein. As far as we are aware, this information is not available as IDEM has focused on sampling fish from streams, rivers and lakes, but not constructed wetlands and fish ponds.

Training The Next Generation

One of the missions of the Indiana Water Resources Research Center, and all Water Centers, is to train the next generation of water scientists. This project successfully funded research for three undergraduate students in Dr. Sepulveda’s lab.

 

Contact Laura Esman, Managing Director, to request a printed copy of this factsheet.

NIWR Logo
USGS Logo
USGS Logo