Description
Per- and Poly-Fluoroalkyl Substances (PFAS) are a class of thousands of chemicals that are known as “Forever Chemicals”
- They can persist in our bodies and in the environment for periods ranging from several years to decades (e.g., 16 years in the human blood and 184 years in soil) before being excreted or transferred to other media, but they do not break down in nature.
- Unlike many other toxins, over time PFAS build up in individual organisms (bio-accumulate), and build up in the food chain (bio-magnify) which can result in fish, game, and agricultural products that are unsafe to eat.
- PFAS have spread throughout our world and can be found in soil, water, air and in most living things as well as in untold numbers of consumer and agricultural products.
- Virtually all products containing PFAS end-up in landfills and wastewater treatment plants via household trash and manufacturing and commercial solid wastes, and via wastewater from household, factories, and other businesses, and landfill leachate..
- Two of the most studied PFAS chemicals are PFOS and PFOA.
Public Health and Drinking Water
- A range of animal and human studies have shown that some PFAS can cause cancers of the liver, pancreas, kidney, bladder, testes, prostate, thyroid, and breast.
- Other health effects of PFAS are thyroid disruption, liver problems, birth defects, and immuno-suppression.
- The US Environmental Protection Agency (EPA) has set voluntary Health Advisory Limits for PFOS and PFOA in drinking water at 0.020 ppt and 0.004 ppt respectively.
- Based solely on health criteria EPA has also set the Maximum Contaminant Level Goal (MCLG) for PFOS and PFOA in drinking water at 0.
- However, also taking into consideration the cost and difficulty to industry and the public of reaching purely health-based standards, EPA set the following higher enforceable Maximum Contaminant Level (MCL) standards for drinking water with a 2029 deadline to meet them:
- PFOS – 4.0 ppt
- PFOA – 4.0 ppt
- PFHxS – 10 ppt
- PFNA – 10 ppt
- HFPO-DA (commonly known as GenX Chemicals) – 10 ppt
- Mixtures containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS – 1 (unitless) Hazard Index
- EPA estimates that drinking water is typically about 20% of the total exposure to PFAS. Other routes of exposure (air, direct contact with products, food, etc.) are not yet regulated.
PFAS Removal and Commercial Fertilizers
- The treatment process at wastewater treatment plants produces treated water or effluent, and sludge known as biosolids.
- The treatment process at conventional wastewater treatment plants is not designed to remove PFAS chemicals which remain in the effluent and biosolids; nor are effluent or biosolids tested for PFAS before discharge to streams (effluent) or use as fertilizer (biosolids).
- Existing PFAS removal technology such as granular activated carbon (GAC) and reverse osmosis are mainly effective on contaminated water, not solids like soil or the solids in biosolids.
- Although not a permanent solution, storing or disposing of contaminated biosolids in a lined landfill can prevent release of PFAS into the environment in the short term.
- De-watering biosolids and treatment of the liquid portion with existing technology can greatly reduce the volume of remaining contaminated material for interim disposal or future treatment.
- Commercially available methods to capture and remove PFAS from de-watered biosolids are under development.
- Treatment technologies being pursued are:
- Biological decomposition (organisms)
- Chemical separation (binding)
- Physical separation (weight)
- Partition to water (filter)
- Incineration (above 10000C) (fact check – 2,000C ?)
Bottom Line:
- PFAS chemicals cause cancer and other diseases.
- PFAS is found throughout the food chain and in thousands of everyday products.
- Consumers can reduce their own exposure to PFAS:
- by using available guides and purchasing PFAS-free products,
- avoiding food grown on land or with feed fertilized with untested biosolids or treated with PFAS containing pesticides
- using filters rated to remove PFAS from drinking water.
- The enforceable EPA limits for selected PFAS in drinking water which begin in 2029 are higher than the voluntary health advisory levels.
- Land application of biosolids that contain PFAS contaminates soil, water, wildlife, livestock, crops, and animal feed leading to contaminated eggs, milk, meat, produce, fish, and game.
- Commercially produced methods to capture and remove PFAS from water are available, and are under development for de-watered biosolids..
Want to learn more or volunteer? Get in touch with us!
Frequently asked questions
Below are a few FAQs about this project. Click the plus sign to see the answers.
Get Involved: If you would like to learn more about how you can help educate the public about PFAS, please contact Barbara Walsh at barbara.walsh@rockbridgeconservation.org.
This is an educational project of Rockbridge Conservation and does not yet have a project lead. However, you can contact Barbara Walsh to learn more.
Our PFAS working group has presented to the Maury Service Authority and other organizations. They have also put out a webinar (hosted by Rockbridge Conservation) in 2022. They have written letters to the editor and are working with local schools and governments to find solutions.
No! Although we encourage all of our committee volunteers to become members. Committee leadership must be members of Rockbridge Conservation.