Fluorocarbons and the Environmental Groundwater Monitoring Industry
When Waterra started in the environmental industry in 1987, the environmental groundwater business was much simpler. Back in those days, many hydrogeologists were using homemade equipment to purge and sample their monitoring wells. Then, as the legislation regulating groundwater developed, the market for small diameter pumps grew. Techniques and methodologies for sample collection became more defined and it seemed like there was a new paper each month claiming that a new device was superior to others for a particular type of sampling.
A common theme in the ’80s was the comparison of different polymer materials for use in sample collection. At the time, the material that was held up as the gold standard for groundwater sampling was Teflon. Ironically, today one of the latest environmental concerns is Polyflouroal Substances (PFAS) – a byproduct from the production of Teflon and related fluorocarbon polymers as well as an additive in numerous other products. This has forced the industry to change its approach to the materials used in groundwater monitoring.
So what are PFAS or PFC’s and why are they bad?
PFAS (also referred to as Perfluorinated chemicals, “PFC’s”) are a group of man-made synthetic chemicals that have been in use since the 1940s. These chemicals were used in a wide range of industrial and consumer applications. PFC’s are well‐known for thermal and water resistance, contributing to their use in a variety of applications including:
- nonstick coatings
- waterproof /oil resistant leathers & fabrics
- paper & cardboard packaging
- electrical wiring insulation and coatings
- firefighting foams
- fast food packaging
- pesticides
- shampoo
- paint
PFC’s are very stable compounds that are resistant to breaking down in the environment. Their characteristics seemed like a perfect fit for the environmental groundwater industry but unfortunately, PFC’s have received attention as an emerging contaminant that has a pathway to enter the environment, may pose human health or environmental risk and does not have federal regulatory standards.
PFC’s are comprised of fluorinated carbon chains that are attached to functioning groups (such as alcohol, sulphuric acid, etc.) PFC’s are often described in two groups: long-chain and short-chain, depending on how many carbons are contained in its chemical structure. According to the EPA, the following PFC’s are suspected drinking water contaminates that have gone unregulated until recently.
Long Chains
- Perfluorooctanoic adic PFOA
- Perfluorooctanoic sulfonate PFOS
- Perflourononanioc acid PFNA
Short Chains
- Perfluorohexacene sulfonic acid PFHxS
- Perfluorohexanic acid PFHxA
- Perfluorobutanesulfonic acid PFBS
Health Concerns
PFC’s are highly water-soluble and can dissolve in the aquatic system very easily. In the USA, drinking water sources such as lakes rivers, streams and groundwater have been finding low levels of PFC’s all over the country. PFCs are found in elevated levels in the aquifers around airports, military installations, and manufacturing facilities.
In a June 2019 Technical Brief, the EPA admitted that “due to the widespread use and persistence in the environment, most people in the USA have been exposed to PFAS. There is evidence that contained exposure above specific levels of contained PFAS may lead to adverse health effects.
Long-chain PFC’s have been found to have comparable bioaccumulation potential as DDT and PCB’s and have a half-life of more than five years in the human body. Alternatively (PFBA) is a short-chain PFC with only four carbons and its half-life in humans is three to four days. The EPA and Agency for toxic substances and disease Registry (ASTDR) have both reported that the most consistent health effect of PFC exposure is increased cholesterol levels. There have also been findings related to:
- Interference with the body’s natural hormones
- Birth defects
- Low infant birth weight
- Effects on the immune system
- Cancer
The film “The Devil We Know” is a 2018 investigative documentary film by director Stephanie Soechtig that touches on this very subject. The film follows the Citizens in West Virginia as they battle a powerful corporation after learning that it has consciously been dumping a toxic chemical into the local water supply. Allegations of health hazards from Teflon, and the DuPont corporation‘s potential responsibility. Well worth the watch.
What is Being Done to Remediate the Problem?
Like the groundwater monitoring industry, most manufacturing of PFC’s has been greatly reduced or abandoned completely. But there are still PFCs being produced for specific industries today.
At the moment, there are no federally enforceable allowable levels of PFC’s in drinking water but in May 2016, the EPA released a lifetime health advisory of 0.070 micrograms per litre of PFAS and PFOS (individually or combined) for exposure from drinking water. Individual states and municipalities are now developing state PFC guidelines for monitoring and reducing PFC’s in the environment.
The EPA has created a few methods to accurately and constantly measure PFC’s. Method 537 is used to analyze 14 different PFAs in drinking water. This method was updated in 2018 to include 4 more types of PFAS. These methods are ever-changing and evolving and this method is expected to be updated yet again in 2019 to capture even more types of PFAS.
In 2019, the EPA unveiled an action plan that would place PFOA and PFOS on the hazardous substances list. They are also developing groundwater clean-up remediations as well as increasing research efforts to develop even more methods to detect PFAS.
Current treatment methods
The influent concentrations and treatment conditions will determine which treatment methods are used. Several treatment methods have been found to remove up to 90% of all PFC’s. The most common methods of treating PFC’s are active carbon, anion exchange, membrane filtration and AOP (advanced oxidation processes).
How has this affected the groundwater monitoring industry?
The SW-846 method is under development by the EPA. This method states that only PSAF-free HDPE sampling contains tubing and sampling tools must be used while testing in the field and the laboratories. Even consumer goods brought to the sampling sites need to be PFAS-free so that they do not contaminate samples. Advanced field sampling and laboratory hygiene protocols must take place to ensure that results reflect actual PFAS levels.
At Waterra, we have plenty of groundwater testing equipment that is PFAS free: tubing, Waterra foot valves, etc. We will continue to monitor and evolve our products and processes as PFC research develops.
Sources
https://www.cancer.org/cancer/cancer-causes/teflon-and-perfluorooctanoic-acid-pfoa.html
https://www.youtube.com/watch?v=gwZSXdjAqSk
https://www.evoqua.com/en/markets/Remediation/Pages/What-are-PFCs.aspx