PFAS Fund: Research and Grant Opportunities

• Movement of PFAS from contaminated agricultural materials (e.g., manure, hay or other plant materials, carcasses, discarded milk) to water or soil 
  
• Remediation or disposal options for PFAS-contaminated agricultural materials
  
• Markets for contaminated hay: How much PFAS is transferred from contaminated hay to soil? What levels and types of PFAS in hay would be safe for use as mulch for gardens or silt barriers for construction projects? Would the revenue from such uses be sufficient to keep pastures in hay?
  
• Horses and horse manure: To what extent do PFAS accumulate in horses, horse manure, and soil when PFAS-contaminated hay is the primary food source for horses? How does this vary by the amount of PFAS in the hay? Proposals might include markers of horse health and/or assessment of possible transfer pathways from horse manure to plants or chickens.
  
• Food sources for pigs: Which PFAS soil levels are appropriate for producing feed for pigs? How does this vary by feed type?
  
• Livestock correlation studies: the correlation between PFAS in more readily sampled media (including blood, milk, eggs, or ear punches) and in muscle or organ tissue. Researchers are encouraged to submit a proposal for a specific understudied type of livestock.
  
• Communication strategies for impacted producers: Consumers are encouraged to ask farmers about PFAS and farmers are encouraged to inform their customers about the presence of PFAS compounds in their farm's soil. How are impacted producers navigating this communication? How can producers effectively communicate about technical topics such as action levels for food products, the nuances of low-level PFAS exposure through food, or the presence of their farm on the DEP PFAS investigation map? Proposals might include interviews with producers and/or the development and testing of materials in collaboration with producers, ideally bringing together the academic literature on risk communication and the challenges identified by impacted producers.
  
• Christmas trees as an alternative agricultural product: How much PFAS is taken up into trees and needles? How does this vary by maturity – e.g., how much will have accumulated by typical harvest time? Would there be health risks to young children if a Christmas tree sheds needles in a home? Would there be health or environmental risks if a Christmas tree grown on a PFAS-impacted field is fed to goats or used as a substrate for seeding clam beds? How would this vary according to the level of PFAS in the field where the Christmas trees are grown?
  
• Pollinators: To what extent are PFAS accumulating in pollinators, pollinator food sources, hives, and honey? How does accumulation vary by level of contamination in soil and surface water and by hive distance from sources of contamination? Proposals might also include assessment of pollinator and hive health.
  
• Questions based on research priorities: Researchers may also propose other research questions that will: address one of the PFAS Fund’s identified research priorities (see Major Grants, Round 2 below and the full Targeted Grants RFA), benefit Maine farm viability, fill a gap in the literature, and are answerable through a research project of less than 18 months duration and under $100,000 in funding. These proposals may include extension of a current research project or a pilot study that would provide preliminary data necessary for developing a larger study.
  

Priority 1: PFAS in Agricultural Settings: Soil, Water, and Plant Studies

This category examines the fate and transport of PFAS in agricultural soil, water, and crop systems. Topics include, but are not limited to:

• Studies related to the influence of soil properties on PFAS contamination, including residence time and modeling;
• Changes in PFAS levels in soil over time; how different variables influence the rate of change;
• PFAS sorption and transport kinetics in soil;
• Irrigation-based PFAS migration pathways through soil-water systems;
• PFAS transfer factors (also known as bioconcentration factors) such as transfer from:
  • irrigation water to soil,
  • soil to groundwater, and
  • soil or water to crops consumed or utilized by animals or humans (e.g., vegetables, fruits, forage, grain, or specialty crops such as Christmas trees).

Priority 2: PFAS in Agricultural Settings: Animal and Animal Product Studies

This category includes research to broaden the understanding of PFAS uptake and movement through livestock and poultry and their fate in animal products (e.g., milk, eggs, meat).
Topics include, but are not limited to:

• Predictive models for soil to forage crop to livestock to food commodity pathways;
• Livestock and poultry transfer/bioconcentration factors and factors that affect them (e.g., forage/feed transfer factor for meat/milk/eggs, how transfer factors change seasonally);
• Livestock correlation studies (e.g., the correlation between PFAS in more readily sampled media, including blood, milk, eggs, or ear punches, and muscle or organ tissue);
• Livestock and poultry elimination kinetics studies;
• Influence of feed additives/binders on PFAS levels in animals and animal products;
• Accumulation of PFAS in various value-added dairy products (e.g., cream, yogurt, butter, cheese, etc.); and
• Pollinators: bioaccumulation of PFAS in pollen and nectar; assessment of pollinator and hive health; assessment of potential impact on crops that require pollination (e.g., blueberries)

Priority 3: Understanding and Managing PFAS on the Farm

This category includes research designed to 1) enhance the management and understanding of PFAS in agricultural settings and 2) develop tools to increase the speed and reliability of on-farm management decisions related to PFAS contamination.

Topics include, but are not limited to: 

• Development of decision support tools (e.g., when it is safe to return farm products to the market? When can animals be safely released for slaughter post-depuration?);
• Soil management strategies and their relative effectiveness in reducing the impact of PFAS contamination (e.g., till versus no-till);
• On-field crop management strategies to reduce PFAS (e.g., harvest timing, forage species selection, pasturing strategies);
• Post-harvest investigations of how PFAS levels change throughout the life cycle of forage crops, from harvesting in the field to storage, and potential management practices related to those changes
• Alternative crop production potential on PFAS-contaminated land (e.g., grains, maple syrup, Christmas trees);
• Risks and benefits of animal fiber production on PFAS-impacted land;
• Use of biomass from impacted fields (e.g., construction, textiles, mulch); and,
• Treatment and/or low-risk disposal methods for PFAS-contaminated byproducts (biomass, manure, carcasses, milk, compost).

This study examines how PFAS present in agricultural soils become airborne during tillage events. Contaminants are often concentrated in fine soil particles, which can be lifted into the air as dust, potentially impacting environmental and human health. To understand this process, soil samples from multiple fields will be analyzed to determine how PFAS are distributed across different soil particle sizes. At one site, dust will be collected before, during, and after a field preparation to assess how much and how far contaminants travel. The results will help identify which soil components pose the highest risk for airborne transport and how their PFAS levels can be used to predict potential dust contamination. Findings from this study will provide valuable insights for farmers, researchers, and policymakers working to mitigate the risks of airborne soil contaminants in agricultural settings.

This project aims to investigate whether biochar can be used as a soil amendment to immobilize PFAS in the soil and reduce its bioaccumulation in the edible parts of vegetable crops, such as lettuce and tomatoes. The study will address several key questions: the optimal application rate of biochar in the soil, the frequency with which additional biochar should be applied after the initial amendment, and low-cost modification techniques to enhance biochar's ability to adsorb short-chain PFAS from the soil. This research will involve both laboratory and field studies. The findings will contribute to developing practical guidelines for farmers on the use of biochar in PFAS-affected soils.

Plant uptake from contaminated soils is a major way PFAS compounds enter our food systems. In the case of milk and meat, there is particular concern about uptake of perfluorooctane sulfonic acid (PFOS) by forage crops due to the prevalence and toxicity of PFOS. Being able to accurately predict how much PFOS moves from soil to plants to animals is critical for assessing risk and developing mitigation strategies, but one major factor complicating those predictions is that PFOS, like some other PFAS compounds, can be created through the transformation of "precursor" compounds. Concentrations of these PFOS precursors can vary widely from field to field and could be contributing to the high variability of plant PFOS uptake rates that have been observed. We will conduct paired greenhouse and field studies to assess whether PFOS precursor compounds in soil influence PFOS uptake rates from soil to grass, and to what extent.

One of the first steps in understanding how to manage PFAS on the farm is timely detection. Currently, this first step is burdensome for farms due to the slow turnaround time and high cost of analytical testing. Typically, it takes over a week to obtain test results at a cost of $200-$400 per sample, with multiple samples needed for each study. This proposed research will address this challenge by developing and demonstrating portable electrochemical sensors that can be used for rapid, on-site, and inexpensive testing. These user-friendly devices can be operated by farmers to obtain quick in-house results and determine the level of PFAS in different samples at different locations and times, hence obtaining a better understanding of the contamination issue for a timely response.

The research team seeks to develop strategies to reduce PFAS contamination in livestock animals, which will help protect agricultural integrity, public health, and animal welfare. This study will be conducted on ewes from an already awarded EPA grant, but adding additional samples to model the kinetics of PFAS bioaccumulation and depuration, as well as being able to sample during an entire lactation (beyond 81 days in milk). The first objective will focus on how PFAS moves through the animal's body during gestation, lactation, and depuration (cleaning) after being fed clean feed. The results will guide regulatory measures for PFAS contamination and its impact on animal products such as milk, meat, and eggs. The second objective examines the effects of feeding management practices during the weaning phase. The research will explore how early-life exposure to PFAS affects bioaccumulation of PFAS in animals and the potential for reducing contamination through clean milk replacers.

This project will examine how per- and polyfluoroalkyl substances (PFAS) on two biosolids-contaminated farms in Maine are transferred to poultry and eggs. We will consider exposures through direct consumption of contaminated soil, insects, earthworms, and airborne dust particles. We will monitor seasonal changes in eggs and test the effectiveness of different coop setup interventions (location changes, dust minimization, platforms, soil barriers) for minimizing PFAS exposure. Data will be used to provide advice for farmers for minimizing PFAS contamination in chickens and eggs and to develop soil screening values protective of public health.

Current PFAS cleanup methods are costly, energy-intensive, fail to fully remove PFAS, damage soil fertility, and create additional environmental waste. This project will use activated carbon coated on a plasma electrode to capture PFAS from soil. After capturing sufficient PFAS onto activated carbon, plasma will be activated to break down the PFAS molecules and refresh the activated carbon. By periodically activating plasma, this method not only destroys the PFAS but also refreshes the carbon's ability to capture PFAS. This approach is expected to deliver key benefits: 1) energy efficiency, by using non-thermal and low-power plasma reactions; 2) long-term effectiveness, by fully breaking down PFAS instead of just trapping them; 3) soil fertility and safety, by avoiding harmful soil disruption and generating nutritious nitrogen species; and 4) sustainability, by reducing waste by periodically refresh activated carbon.