PFAS chemicals are dangerous because they are highly toxic, very persistent in the environment, largely unregulated, and  released into air, water, and land.  

PFAS compounds are making it onto our farmlands and into our gardens. 

This page explains how PFAS are collected by wastewater systems, run through treatment plants,  and sent out to farms and  gardens  -- and what you can do about it.

Key Points. 

Please scroll down for details on each point.

1. PFAS compounds are dangerous because they are highly toxic, persistent, and mobile in water. 

2.  PFAS compounds are out of control due to widespread use, large numbers of compounds, and limited regulation.

3.  PFAS compounds are released from many sources into wastewater systems that transport them to wastewater treatment plants.  Wastewater treatment plants do NOT breakdown or destroy PFAS compounds.  They are retained  in liquids known as "wastewater residuals" and solids known as "sludge." 

4. Sludge containing PFAS from wastewater treatment plants is sent to disposal sites or other uses including application to land and use in gardening products. 

5.  Evidence is emerging that applying biosolids to land can create hazards at farms and from packaged farm and garden products.  So far, much of this evidence is from individual cases.  Farms contaminated by PFAS and have been forced to discard food products or even to cease farming.  Broader assessments are desperately needed. 

6.  The practices to distribute and release PFAS compounds after wastewater treatment are not regulated by the federal government.  It is perfectly legal under federal law for a wastewater treatment plant to send PFAS to farmlands or home gardens. 

7.  Some states have begun to act.  Maine, Wisconsin, and other states are beginning to put limits on application of biosolids or to collect data about the topic.

8.  Some wastewater system operators are  concerned.  Some are seeking to keep PFAS out of their waste streams. Many are monitoring for PFAS. 

9.  More actions are needed to ensure that PFAS compounds do not contaminate farms and gardens. 

This site will track science and policy developments and opportunities for PFAS actions for local and state activists.   Sign up for our email newsletter here.  (Note:  Signup will be activated June 1)

Details for the Key Points

1. PFAS chemicals are dangerous

PFAS (Per- and Poly-fluoro alkyl substances) compounds are a group of manufactured chemicals that have been used in industry and consumer products since the 1950s. 

The three most important reasons that PFAS compounds are dangerous:

• Persistence in the Environment: PFAS are long-lasting chemicals that break down very slowly over time. Some may not break down at all.   Because of their widespread use and persistence, they can build up in people, animals, food chains, and the environment.  hey are often referred to as “forever chemicals” because they persist in the environment. 
   
• Health Hazards: Exposure to even very low levels of PFAS compounds is associated with a higher risk of adverse health conditions. These include raised cholesterol levels; kidney, prostate and testicular cancer; asthma; thyroid disease; liver damage, and obesity.  (Note:  we are reviewing this list from ATSDR from other authoritative lists and may incorporate some other endpoints.)
   
• Mobility:  Unlike most highly persistent compounds, PFAS tend to be highly mobile in water and so pose a greater risk to contaminate water bodies.

2. PFAS Compounds are Out of Control due to Widespread Use,  Large Numbers of Compounds,  Limited Regulation. 

Widespread Use of Large Numbers of Compounds

• PFAS compounds are used in many products including packaging, clothing, textiles, fire-fighting foam, firefighters clothing, cosmetics and personal care products. 
• PFAS are used  at manufacturing industries  including tanning, chemical production and others.
• PFAS have been used in fire fighting foam known as AAAF used in training for fire fighters as well as in extinguishing fires. Military sites, airports, ports, and fire training facilities often have very high levels of PFAS in surrounding water.
• There are tens of thousands of PFAS compounds.  They are manufactured as mixtures.  Researchers have described the overall qualities of PFAS pretty well.  But the sheer number of PFAS substances makes it impossible to specifically describe the specific toxicities of every one one. 

Limited Regulation by the Federal Government

• Unfortunately, the chemical industry has successfully demanded that traits of individual PFAS be specified before they are subject to meaningful regulation. 
• Emissions and releases of PFAS are not regulated by the US.  PFAS can be freely emitted to air and water,  and they can be dumped into landfills and used in biosolids applied to farms and other lands.
• Uses in products are not regulated in the US, with a few exceptions limiting use of AAAF firefighting foam.  They can be freely used  in any product.
• Some requirements related to removal or cleanup of PFAS were adopted in April 2024 by EPA
  • Drinking Water:  US EPA has adopted enforceable limits for five PFAS compounds in drinking water (EPA1)(EPA2). 
  • Hazardous Substance Remediation:   EPA  has  announced that it will list two legacy PFAS compounds as hazardous compounds subject to  the Superfund (CERCLA) statute (EPA3) (EPA4).  These compounds are PFOS and PFOA.
• These are welcome steps, but they cover only a handful of PFAS compounds.   Moreover, these rules do not directly stop uses and releases  of PFAS.  Costs for drinking water treatment to remove PFAS fall to those who operate the drinking water systems, often municipalities or regional governments. More is needed to prevent releases of all PFAS compounds

3.  Many sources  release PFAS compounds into wastewater systems that transport them to wastewater treatment plants.  These plants do NOT  destroy the  PFAS. 

PFAS are used in many locations.  As a result, PFAS are  released at many locations.   PFAS are released into sewer and wastewater systems. 

Most are connected to  larger wastewater systems that lead to a sewage treatment plant (also known as a wastewater treatment plans.)

There are more than 14,000 wastewater treatment plants in the US. (Ref1) Many of these are owned and managed by municipal or regional governments.  Some are managed by businesses or the military.  Many are older; updating and improving them is a goal of the Bipartisan Infrastructure Bill passed in 2023.

What these plants have in common is that they do not break down PFAS compounds.  The same amount of PFAS that goes into a wastewater treatment plant  at the beginning then comes out of the plant at the end of the treatment process. .  Often, the exact types of PFAS that emerge are somewhat different from those that go in.  But in either case, they continue to be just as dangerous when they come out as they were when they went in.  (REFs2)

Wastewater treatment plants produce liquids known as wastewater residuals and solids known as sludge.  Liquid and solid wastes from treatment plant are often composted with other substances to create "biosolids" that have a more tractable texture than the original materials.  The PFAS is retained in the biosolids.  Sludge is converted into "biosolids" by further drying and fluffing so that the biosolids are dryer and fluffier than the sludge. 

4.  Biosolids from wastewater treatment plants are sent on to uses including application to land and use in gardening products or other waste facilities

Biosolids left after wastewater treatment plants have to be sent somewhere.  They accumulate over time, often at large volumes.

There are three options for biosolids produced at a wastewater treatment plant:

a.  Disposal through placement or burial at a solid waste facility (often known as a "dump")

Sending biosolids to a solid waste facility gets the material away from the wastewater treatment plant.  However, this is often only a temporary solution.  Solid waste facilities vary greatly in their ability to permanently contain the materials put into them.  Most of them are located outdoors and subject to precipitation that leaches through the site.    The severity of leaching is affected by the design and operation of the facility and weather.  Some facilities have advanced systems to monitor leaching and prevent the leaching liquids (known as "leachate") from leaving the site.  Others do not.  Leachate from solid waste facilities may be sent back to a wastewater treatment plant. 

Recent evidence suggests that quite a lot of PFAS may leach out of solid waste disposal facilities.  We will post a separate resource page discussing this issue at a later date and link it here. 

b.  "Disposal" through incineration or other "thermal treatment" option.

Additional explanation will be added here, but suffice it to say that neither incineration nor thermal treatment has been shown to actually destroy PFAS chemicals.  These methods are most likely to re-distribute PFAS from the wastewater back into the air. 

c.  Application of  biosolids to lands including farm land.

Estimates of the use of biosolids applied to land range from about 40% to 60%.  R3 EPA5 R4

Land application is usually by spraying biosolids across a land area, for two reasons.

• Biosolids may offer beneficial nutrients  (such as nitrogen and phosphorous) for soils and act like a fertilizer.  Application of any source of nutrients has to be carefully managed to ensure that the nutrients are  usefully absorbed by soils  and not run off into streams to contaminate surface waters.  Nutrient contamination is a severe problem in many areas. 
• The second reason is to spread out any contaminants.  These can include both microbes such as

Use of Biosolids in Products for Agriculture and other Land Use or for Gardening

A second option is for biosolids to be distributed  in bagged products sold for agriculture, land management, or gardening.   Biosolids may be used in products sold to golf courses for turf management and in products marketed to gardeners and even if marked as "organic." 

The Sierra Club Staff and PFAS team, in collaboration with The Ecology Center, found PFAS contamination in several products in 2001.  Here is the Press Release,  Full Report, and fact sheet summary.. 

We are preparing additional information about this and will add it here when available.

5.  Evidence is emerging that applying biosolids to land can create hazards at farms and from farm products. 

Several cases have emerged where farm products or produce have been contaminated by PFAS.   These will be summarized here. 

• bacteria or viruses as well as chemical contaminants. 

Concerns about chemical contaminants in biosolids applied to lands are not new.    Toxic metals such as mercury, lead, and arsenic were common in biosolids until they were regulated in the 1990s.  Metals can be taken up into plants  sold as food for humans or livestock such as beef cattle, dairy cows,  or pigs.   EPA  adopted limits on metals in biosolids used for farming or gardening. 

This was implemented by removal of metals from wastewater, known as "pretreatment."  Similar approaches could remove PFAS.  EPA is advocating use of permit conditions under the wastewater discharge permit program authorized under the federal Clean Water Act (known as NPDES for the National Pollutant Discharge Elimination System_ to accomplish this.

The Clean Water Act in Section 405 requires EPA to regulate chemical contaminants in biosolids and to review its rule every two years.   EPA6

Clearly, this has not occurred.

Farmers in Maine have sued EPA seeking to compel the agency to regulate PFAS in biosolids.  R7

6.  The practices to distribute PFAS compounds after wastewater treatment are not regulated by the federal government. 

It is perfectly legal under federal law for a wastewater treatment plant to send PFAS to farmlands or home gardens. 

EPA has included the topic of "biosolids" in its Roadmap for PFAS.  This strategy includes actions for many areas where EPA has authority, as well as for developing methods and conducting research.  It mentions PFAS in Biosolids, and there is a widespread impression that EPA has committed to taking action.  However, this is not the case.

Rather, the Strategic Roadmap promises much less.  The Roadmap commite only to conduct a risk assessment for the two legacy PFAS compounds -- PFOA and PFOS.  These were some of the first PFAS chemicals to have been introduced.  They are probably the most notorious due to well known effects. 

EPA has taken the position that "there isn't enough data" to manage PFAS in biosolids.  However, it is important to note that EPA has not committed to obtaining such data from the PFAS manufacturers nor to doing its own research.  This seems like an empty excuse for inaction.

The language for the commitment made by EPA in the Roadmap is:

• Finalize risk assessment for PFOA and PFOS in biosolids that will serve as the basis for determining whether regulation of PFOA and PFOS in biosolids is appropriate.

Meanwhile, nothing has been released toward the promised risk assessment, which is now said to be due by the end of 2024.  Nor is it clear how this risk assessment will be applied to  make a determination for regulation of PFAS compounds in biosolids. 

We are also looking into the review of a proposed broader framework for evaluating contaminants in biosolids considered by the Science Advisory Board in the fall of 2023.  More will be reported later on that

7.  Some states have begun to act.  Maine, Wisconsin, and other states are beginning to put limits on application of biosolids or collect data about the topic. 

See the Safer States website for information about state actions on PFAS overall.

More information about state actions and priorities will be added here

8.  Some wastewater system operators are  concerned.  Some are seeking to keep PFAS out of their waste streams. Many are monitoring for PFAS. 

More information will be added here.

This site will track science and policy developments and opportunities for PFAS actions for local and state activists.  

You will be able to sign up for our email newsletter here. 

(Note:  Signup will be activated soon)