There have been a lot of news articles, blog posts, and stories about “Forever Chemicals” and per- and polyfluoroalkyl substances (PFAS), but few of these stories really gives you any idea of what to do next. PFAS are a grouping of man-made fluorinated organic chemicals, including PFOA (PerFluoroOctanoic Acid) and PFOS (PerFluoroOctane Sulfonate), that have a wide range of use in industrial applications and commercial goods. These chemicals contain Carbon-Fluorine and Carbon-Carbon bonds that are very strong, do NOT occur naturally, can bioaccumulate, and are difficult to break down, hence, the term “forever” chemicals. Most of these stories basically just say “Exposure to PFAS chemicals has been associated with cancer, reproductive harm, developmental harm, high cholesterol, damage to the immune system, hormone disruption, and liver and kidney damage”, but is “Associated with” the same as “CAUSED”?
Causal Relationship the relationship established that shows that an independent variable, and nothing else, causes a change in a dependent variable. It also establishes how much of a change is shown in the dependent variable.
Independent Variable “An independent variable is defined as the variable that is changed or controlled in a scientific experiment. It represents the cause or reason for an outcome on the dependent variable”
Dependent Variable “The variable or parameter that may change as a result of the manipulation of the independent variable.”
Therefore, Independent variables are the variables that the scientist changes to evaluate the influence or lack of influence on the dependent variable, i.e., a change of one thing (independent variable) results in a change of another thing (dependent variable).
Examples:
We can agree- “Consumption of a lot of sugar (independent) tends to lead to tooth decay which is a causal relationship between sugar consumption and tooth decay (dependent)”
We can also agree - “People who drink may also smoke, but one doesn't cause the other.”
The Source and Origin
Because these man-made compounds are resistant to oil, water, heat, and grease, these chemicals were introduced to many consumer and industrial products and used as part of firefighting foams. In the 1940s, these compounds were used to produce water and stain-resistant clothing, fabrics, and carpeting. Firefighting foams were used by the military, in industrial applications, and on airfields. industrial and agricultural chemicals such as pesticides and herbicides, contain PFAS and they are even added to cleaning products. Do any of these brands sound familiar, "Scotchgard, Teflon, Gore-Tex?"
Because these chemicals could prevent or inhibit grease migration and moisture penetration, the FDA approved the use of PFAS for food packaging, cookware, and food processing and "Long-chain PFCs (long-chain perfluorinated compounds) for specific food-contact uses such as coatings on fast-food wrappers, to-go boxes, and pizza boxes.” Even toilet paper contains PFAS! It has been suggested that toilet paper may be a significant source of Forever Chemicals in domestic wastewater discharges, i.e., wastewater or sewage treatment plants discharging to surface water sources. (SO, are we planning to go back to using the tersorium, the Roman sponge on a stick??).
For the microwave popcorn and "Teflon" user, you also have some decisions to make. "One of the problems with microwave popcorn lies in the microwave-safe bag that houses the kernels. According to a December 2013 report in Environmental Health Perspectives, microwave popcorn bags contain chemicals called perfluorooctanoic acid (PFOA), which is the same chemical used in Teflon® nonstick coating, and PFOS. Recent studies have shown these chemicals are also present in many other consumer products including dental floss, toothpaste, shampoo, nail polish, feminine hygiene products, diapers, sanitary napkins, and even eye make-up. It has been estimated that over 180+ million Americans have tap water that may contain detectable levels of the Forever Chemicals, i.e., PFOA and PFOS.
The Current Status
The available data indicates that these compounds have the following characteristics:
The Forever Chemicals can bioaccumulate in the environment, animals, plant tissue, and humans, which means these chemicals can build up over time in the food web and water cycle.
-
The chemicals have rather long half-lives that can range from 72 hours to over 10 years.
-
We are routinely exposed to these chemicals based on our lifestyle and consumer products. Therefore, we can limit our exposure by making lifestyle changes and changing how and where raw material is sourced, products are manufactured and used, and how products and chemicals are disposed of. Currently there are a number of significant questions regarding the level of these chemicals in landfill leachate.
-
These chemicals have been detected in rainwater and agricultural soils where sewage sludge has been applied (biosolids applications). The FDA has detected PFOS in dairy products, meat, and seafood. “The Environmental Protection Agency has concluded that for the general population “the dominant source of human exposure to PFOS is expected to be from our diet.”
-
There is evidence that exposure to PFAS at very high levels is associated with adverse health impacts in humans. The most-studied PFAS chemicals are PFOA and PFOS and these studies indicate that these compounds are associated with immunological problems, reproductive and development problems, can promote the growth of tumors in animals, and can impact the liver and kidneys in humans and cause health effects in animal models. The primary issues that are still not clear are the exposure routes, the differences between dermal exposure (skin contact) and consumption (eating or drinking), and causation to health effects in humans as a function of concentration, exposure route, and duration of exposure.
“The most common route of exposure to PFOS is via the diet, followed by indoor dust, especially for children”.
“Food is a significant source of exposure to PFOS; it has been detected in a variety of foods, including eggs, milk, meat, fish, root vegetables, and human breast milk.”
“PFOS has been detected in finished drinking water samples collected by EPA and others.”
“Inhalation of PFOS is possible; it has been measured in indoor air in residential, commercial, and office settings because of its use in carpets, textiles, paint, furniture, and other consumer products.”
-
“Finding a measurable amount of PFAS in (blood) serum does not imply that the levels of PFAS cause an adverse health effect.”
-
The good news: Because of changes in the production and use of these chemicals in the United States, the blood levels of PFAS appear to be decreasing since 1999. The average blood PFAS level has dropped from about 30 ug/L to about 5 ug/L.
Since 2002, production and use of PFOS and PFOA in the United States have declined. As the use of some PFAS has declined, some blood PFAS levels have gone down as well.
- From 1999-2000 to 2017-2018, blood PFOS levels declined by more than 85%.
- From 1999-2000 to 2017-2018, blood PFOA levels declined by more than 70%.
Currently, there are no established human treatment approaches to manage past PFAS exposure, but blood levels will decrease over time when exposure to PFAS is reduced. However, as PFOS and PFOA are phased out and replaced, people may be exposed to other man-made chemicals that have replaced PFAS.
-
Originally, the EPA set a Drinking Water Equivalent Level (DWEL) for PFOS, assuming 100% of PFOS exposure comes from drinking water, at 0.00037 mg/L or 0.37 ppb (parts per billion). The Lifetime HA (health advisory) for PFOS is calculated to be 0.07 ppb (EPA, 2016).
Note: A Lifetime health advisory is the concentration of a substance that are not expected to cause adverse non-carcinogenic health effects after a lifetime of exposure.
-
EPA Updated their information (2022): The interim updated health advisories for PFOA and PFOS are 0.004 ppt (0.000004 ppb) and 0.02 ppt (0.00002 ppb), respectively. The interim updated health advisories replace the 2016 final health advisories for PFOA and PFOS, which were both set at 70 ppt (0.007 ppb). (ppt is parts per trillion, not parts per thousand)
-
March 29, 2023 - The EPA proposed National Primary Drinking Water Regulations for PFOA, and PFOS and developed a Hazard Index Rating for PFNA, PFHxS, PFBS, HFPO-DA (commonly referred to as GenX Chemicals).
PFOA - Maximum Contaminant Level Goal (MCLG) - 0 ppt
PFOA - Proposed MCL (enforceable level) - 4 ppt
PFOS- Maximum Contaminant Level Goal (MCLG) - 0 ppt
PFOS - Proposed MCL (enforceable level) - 4 ppt
-
The Hazard Index Tool was developed to predict the health exposure to mixtures of chemicals. The Hazard Index compares the concentration of a given chemical such as GenX in the water to the health based value (HBWC) for GenX. The individual fractions for GenX, PFBS, PFNA, and PDHxS and the sum is the Hazard Index Level.
The Proposed HBWC are:
PFHxS 9.0 ppt
PFNA 10.0 ppt
PFBS 2000 ppt
HFPO-DA (GenX) 10 ppt
The calculated Hazard Index Level must be less than or equal to 1.
What Next
Step 1: Do Not Panic!
Step 2: Learn More about these Forever Chemicals and Your Exposure via Consumer Goods, Work and Home Environment, Drinking Water, Diet and Lifestyle.
Step 3: Your drinking water – Are you exposed?
If your drinking water comes from a Water Company or Authority that uses a surface water intake, such as a lake, reservoir, or river that is downgradient of other urban areas or manufacturing, it is more likely that there are some detectable levels of these chemicals in your water.
If your drinking water comes from a private well, groundwater source or spring, it is more likely that the chemicals are not-detectable or at trace levels. Remember, they have detected these Forever Chemicals in rainwater.
Where to find information about YOUR Drinking Water?
If your water comes from a regulated water system or a public /community water supply, we would recommend getting a copy of the Consumer Confidence Report from the supplier. Also, check out the EPA Widget - Safe Drinking Water System- Know Your H20 Tools.
Know the H20 PFOS Hot Spots: PFOS Occurrence Map - Review available information of Forever Chemical levels in your drinking water system.
For private sources such as wells and springs or if the system does not have this data, you should order a Neighborhood Hazard Report to see what activities occur around the water source and you may want to consider getting your drinking water tested - Get Drinking Water Tested for Forever Chemicals.
Regarding water treatment systems for PFAS / PFOS exposure, the "The Water Research Foundation (WRF) found that aeration, chlorine dioxide, dissolved air flotation, coagulation, flocculation, sedimentation, granular filtration, and microfiltration were all ineffective for removing PFASs including PFOA and PFOS. Anion exchange was moderately effective in removing PFOA, highly effective for PFOS, and failed to remove several other PFASs. Nanofiltration and reverse osmosis proved to be the most effective methods of removing even the smallest PFASs. Granular-activated-carbon (GAC) was shown to be adept at removing most PFASs and it may be the average utility's best bet for PFOA and PFOS contamination."
Step 4: Get Yourself Tested – There are blood tests to determine your level of PFOS exposure. Please Note: “Finding a measurable amount of PFAS in blood serum does not imply that measurable levels of PFAS have an adverse health effect.” The ATSDR (Agency for Toxic Substances and Disease Registry) has developed the PFAS Blood Level Estimation Tool, but the Tool requires some estimate of your drinking water Forever Chemical exposure.
In a study conducted in 2015 through 2016 by a National Health and Nutrition Examination Survey for a population of 12 and older, the median blood levels found were as follows:
PFOA: 2 ng/mL*, with 95% of people at or below 4 ng/mL
PFHxS: 1 ng/mL, with 95% of people at or below 5 ng/mL
PFNA: 1 ng/mL, with 95% of people at or below 2 ng/mL
PFOS: 5 ng/mL, with 95% of people at or below 18 ng/mL
*ng/mL = nanograms per milliliter = parts per billion. To convert parts per billion (ppb) to parts per trillion (ppt), multiply value by 1,000.
Step 5: Make a Change – After getting the facts and information make a personal decision and make a change. Where to make this change is up to you and your family, but there are many ways to limit exposure to these chemicals, but this starts when you are aware and informed. After industrial exposure and commercial-use exposure, please remember, the EPA did suggest that dietary intake was likely the dominant source. SO it is TIME TO ACT – but not out of Fear!
We hope you found our blog post useful and we hope you will consider sharing this blog post and educational links to your friends and family and your personal social media platforms. We need to ensure that our fellow citizens and inhabitants of this Big Blue Ball we call ‘Earth’ are properly educated and informed.
References
PFAS in the U.S. Population
PFAS Blood Testing
Per- and Polyfluorinated Substances (PFAS) Factsheet
PFAS Blood Level Estimation Tool
Drinking Water HealthAdvisory forPerfluorooctane Sulfonate(PFOS)
New Fact Sheet on Medical Testing for PFAS
Key EPA Actions to Address PFAS
PFAS Strategic Roadmap: EPA's Commitments to Action 2021-2024
ECHA publishes PFAS restriction proposal
