Forever Chemicals May Be A Thing Of The Past

PFAS, their history, their hazards, and microbial remediation

Photo by Laura Chouette on Unsplash

Introduction

Per- and poly-fluoroalkyl substances (PFAS) are a class of man-made compounds that have been extensively utilized since the 1940s. Fluorocarbons are composed of carbon atoms bound to fluorine atoms, resulting in a chemically stable structure. PFAS possess exceptional durability, rendering them impervious to water, oil, heat, and chemical reactions. This attribute has led to their widespread utilization in diverse industrial and consumer goods. PFAS are used in many products due to their unique properties. Below are examples of products that may contain PFAS:

1. Non-stick cookware:

   • Pans and pots coated with Teflon or similar non-stick surfaces.

2. Food packaging:

   • Microwave popcorn bags.

   • Fast food wrappers and containers.

   • Pizza boxes.

   • Candy wrappers.

3. Stain-resistant treatments:

   • Carpets and rugs.

   • Upholstery and furniture.

   • Fabric protectors like Scotchgard.

4. Water-repellent clothing:

   • Outdoor gear such as jackets, pants, and boots.

   • Camping and hiking equipment.

5. Personal care products:

   • Cosmetics, including foundation, mascara, and lip balm.

   • Dental floss.

   • Shampoo and conditioner.

6. Cleaning products:

   • Stain removers.

   • Water-repellent sprays.

7. Firefighting foams:

   • Aqueous film-forming foams (AFFF) used for firefighting, especially at airports and military bases.

8. Electronics:

   • Wire insulation.

   • Semiconductor manufacturing.

9. Household products:

   • Non-stick and stain-resistant coatings for household items.

   • Anti-fog sprays for glass and mirrors.

10. Industrial applications:

    • Hydraulic fluids.

    • Metal plating.

    • Chemical manufacturing processes.

11. Medical devices:

    • Surgical gowns and drapes.

    • Some implanted medical devices.

12. Paper products:

    • Some paper and cardboard materials.

Ubiquitous Forever Chemicals

Regulatory bodies worldwide have initiated measures to restrict the utilization and discharge of PFAS due to mounting evidence of its possible adverse effects. Efforts encompass the establishment of thresholds for PFAS in potable water, imposing limitations on their use in certain goods, and advancing research on more secure substitutes. The challenge remains to manage the existing contamination and reduce future exposure to these persistent and pervasive chemicals. Per- and poly-fluoroalkyl substances

Chemical corporations such as 3M and DuPont were the first to synthesize PFAS. Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), known as PFAS, were used in the production of non-stick cookware (like Teflon), water-resistant clothing, stain-resistant fabrics, food packaging, firefighting foams, and various other products (see the list above). Their unique attributes made them extremely advantageous for creating materials that resist oil, water, and stains and withstand hard conditions. Think of those water-resistant clothes that keep you dry in rain or snow.

Health Effects

Exposure to PFAS has been linked to various adverse health effects, including developmental impairments in newborns and children, liver and kidney damage, disruptions in the immune system, thyroid disorders, and an increased vulnerability to certain forms of cancer. PFAS cause adverse health effects in the following physiological systems:

• The immune system
  PFAS can impair the body's immune system, diminishing its capacity to combat diseases and mount an effective response to immunizations. For instance, the National Toxicology Program (NTP) discovered that PFOA and PFOS could inhibit the production of antibodies.

• Hormones

  PFAS can interfere with the body's natural hormones. For example, the C8 Science Panelists determined that PFOA exposure is likely connected to thyroid illness, with varied results for men and women.

• Cancer
  PFAS may raise the risk of several malignancies, including renal, testicular, breast, ovarian, endometrial, and prostate cancer.

• Pregnancy
  PFAS exposure has been linked to an elevated likelihood of developing severe diseases such as hypertension or pre-eclampsia during pregnancy, as well as a potential decrease in newborn birth weights.

• Progress
  PFAS can induce developmental impacts or delays in children, impacting their growth, learning abilities, and behavior. (Fenton et al., 2021; EPA.gov, 2024)

Global regulatory authorities have implemented steps to limit the usage and release of PFAS in response to increasing evidence of its potential negative impacts. Efforts involve setting limits for PFAS in drinking water, restricting its usage in certain products, and promoting research on safer alternatives. The challenge remains to manage the existing contamination and reduce future exposure to these persistent and pervasive chemicals.

Hope

A team at the University of California, Riverside, has been working on discovering which microbes can break the fluorine bonds in hopes of remediating PFAS. This defluorination process uses the enzymes of naturally occurring Acetobacterium and Clostridium microbes. They have been successful in lab experiments to remediate PFAS in wastewater. Their experiments would have practical applications in remediating groundwater where PFAS has infiltrated, a fairly common result around aircraft. (Danelski, 2024; Yu et al., 2024)

PFAS are found in fire-retarding foams used in fire training and plane deicing. Commercial applications may be fully developed in several years. However, there is hope in remediating these forever chemicals through novel bacterial species.

Resources

EPA.Gov. (2024, May 16). Our Current Understanding of the Human Health and Environmental Risks of PFAS. https://www.epa.gov/pfas/our-current-understanding-human-health-and-environmental-risks-pfas

Danelski, D. (2024, July 17). Microbes found to destroy certain ‘forever chemicals’: Bacteria can cleave stubborn fluorine-to-carbon bonds in insidious water pollutants. https://news.ucr.edu/articles/2024/07/17/microbes-found-destroy-certain-forever-chemicals.

Fenton, S. E., Ducatman, A., Boobis, A., DeWitt, J. C., Lau, C., Ng, C., Smith, J. S., & Roberts, S. M. (2021). Per- and Polyfluoroalkyl Substance Toxicity and Human Health Review: Current State of Knowledge and Strategies for Informing Future Research. Environmental Toxicology and Chemistry, 40(3), 606. https://doi.org/10.1002/etc.4890

NIH.gov. (n.d.). Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS). https://www.niehs.nih.gov/health/topics/agents/pfc

Yu, Y., Xu, F., Zhao, W., Thoma, C., Che, S., Richman, J. E., Jin, B., Zhu, Y., Xing, Y., Wackett, L., & Men, Y. (2024). Electron bifurcation and fluoride efflux systems implicated in defluorination of perfluorinated unsaturated carboxylic acids by Acetobacterium spp. Science Advances. https://doi.org/ado2957