What are Polyfluorinated and Perfluorinated Polyfluoroalkyl Substances (PFAS)?
Polyfluorinated and Perfluorinated Polyfluoroalkyl Substances (PFAS) are a class of man-made chemicals that were discovered in 1938 and were utilized in the manufacture of a multitude of consumer products including non-stick cookware, protective coatings (consumer stain treatments, waterproof fabrics, etc), food wrappers (pizza boxes, sandwich wrappers, popcorn bags, etc.), waterproof clothing, and firefighting foams. These compounds were ideal for these applications due to their chemical stability, their high solubility, their ability to be both hydroscopic (water loving) and hydrophobic (water hating) at the same time.
Why are PFASs regulated?
As with many of the compounds and materials that are known to be hazardous today such as asbestos, benzene, and polychlorinated bi-phenyls, PFAS usage increased steadily and became ubiquitous in the environment until it became evident that the same properties that made them useful in industry also posed a threat to environmental and human health.
Recently, the United States Environmental Protection (USEPA) has identified several PFASs, most notably Perfluorooctanoic Acid (PFOA) and Perflourooctane Sulfate (PFOS) as emerging contaminants that need to be regulated and removed from the environment.
How did PFASs get into the environment?
There are a variety of ways that PFASs were introduced into the environment. These include the following:
- During manufacturing of many of the consumer commercial products that were discussed above, several PFASs were utilized in solutions to assist in the deposition of the non-stick surfaces to other surfaces (cloth, metals, plastic, etc.). Once the desirable compounds had adhered to the manufactured items, the residual PFASs were evaporated out and discharged via smokestacks into the atmosphere. From there they were deposited to the ground surface and entered the soil and groundwater.
- Due to their resilient chemical properties, PFASs are resistant to destruction, so manufacturers would dispose of PFAS laden water directly to publicly owned treatment works (POTWs). Since PFASs were not a chemical of concern until recently, POTWs did not treat for them and would discharge them directly into water bodies with treated wastewater or deposit them onto agricultural fields and landfills during biosolid disposal and re-use. PFAS laden industrial waste would also be deposited into landfills along with PFAS containing waste consumer/commercial products. Following land disposal/application, the PFASs leached into groundwater and surface water.
- Due to their unique chemical properties, PFAS containing fire foams were utilized by firefighters to fight fires that could not be extinguished by water such as fuel and chemical fires. The PFOA containing fire foam would then travel into surface water bodies through storm water drains and into soil and groundwater through percolation.
Once the PFASs were in the groundwater, they were incorporated into the drinking water supplies and entered the food chain where they would eventually be ingested by humans. In addition to ingestion, PFASs were introduced into the human body through incidental contact with PFAS contaminated materials.
What are the health effects of PFASs?
Once introduced in the human body, PFASs enter the blood serum and remain in place until they are eventually expelled. The half-life (amount of time it takes 50% of the PFASs to be expelled) of these compounds are up to nine (9) years. Due to their ubiquitous nature, PFASs have been identified in blood serum throughout most of the industrialized world’s population. In fact, the average blood levels of two of the most prevalent PFASs in the general United States population are follows:
- PFOA: 2.1 parts per billion, with 95% of the general population at or below 5.7 parts per billion; and
- • PFOS: 6.3 parts per billion, with 95% of the general population at or below 21.7 parts per billion.
Although additional research has to be completed to fully understand the effects of PFASs in the human body, PFASs have been linked to prostate, kidney, and testicular cancers, increased cholesterol, and potential liver damage.
PFAS Regulatory History
PFASs were identified in human blood as early as 1968 and in public drinking water supplies as early as 1984. Due to the increasing evidence of adverse environmental and human health effects, 3M announced the cessation of long chain PFASs in 2002 and EPA began and Enforceable Consent Agreement with manufacturers in 2003.
There is currently no USEPA Maximum Contaminant Level (MCL) established for drinking water, the USEPA only issued a health advisory for PFOS and PFOA in 2016. As a result, several states have taken it upon themselves to establish regulatory guidance values for groundwater. However, the type and numbers of PFAS compounds regulated at state levels vary greatly and the regulatory guidance values are not consistent. It is likely that PFAS regulation will change dramatically on both the state and federal level in the near future.
There are several sites throughout the country where PFAS impacted groundwater is being treated to protect human health. Remediation of the groundwater is mainly completed through the absorption of PFASs using activated carbon or compound specific polymers. Soil remediation is mainly limited to excavation and disposal at secure environmental landfills as these compounds are resistant to biotreatments and chemical oxidation.
The Future of PFAS Regulations
The environmental regulation and remediation of PFASs are now in their infancy and we can expect significant changes to the ongoing regulation. We will likely see more states increase regulation and provide clearer guidance on remediation requirements once the EPA sets a Maximum Contaminant Level (MCL) and develops health-based risk levels for soil. Additionally, we can expect significant changes to the remedial technologies available and a better understanding of the health risks PFASs present in the near future. This is a developing environmental issue that VERTEX will be following closely.