Environment Articles

by Christine McCullum-Gomez, PhD, RDN, AWC Bogotá

Introduction

Per-and polyfluoroalkyl substances (PFAS) are a large group of synthetic chemicals characterized by a chain of carbon atoms that are bonded to fluorine atoms through a process called fluorination.¹ PFAS are a class of thousands of chemicals known or suspected to be endocrine-disrupting chemicals. According to the Endocrine Society and the International Pollutants Elimination Network (IPEN), “[e]ndocrine disrupting chemicals are individual substances or mixtures that can interfere with our hormones’ natural functioning, leading to disease or even death.”² PFAS are called “forever chemicals” because they don’t biodegrade. Instead, PFAS accumulate in the environment and our bodies over time.³ They are used to make non-stick consumer products: they are oil- and water-repellent and resistant to temperature change. PFAS are used in many consumer products, such as food packaging, non-stick cookware, water-repellent clothing, personal care products and cosmetics (e.g., shampoo, dental floss, nail polish, eye makeup) as well as paints and sealants and stain-resistant carpets, upholstery and other fabrics.^3-5 

Exposure to PFAS is associated with decreased infant and fetal growth as well as decreased antibody response to vaccines in both adults and children, according to a report by the US National Academies of Sciences, Engineering and Medicine (NASEM).⁶ Some of the most studied PFAS, such as PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid), have been linked to serious health problems such as cancer, obesity, thyroid disease, high cholesterol, decreased fertility, pregnancy-induced hypertension, birth defects, liver damage, altered immune response and hormone disruption.^2,7 Studies are now finding similar health impacts from some of the newer PFAS. The NASEM has called for people at higher risk, such as pregnant women, young children and the elderly, to be tested for a subset of PFAS chemicals.⁶

How are we exposed to PFAS?

Individuals are exposed to PFAS in numerous ways, including:

• drinking water from PFAS-contaminated municipal sources or private wells;
• eating fish caught from water contaminated by PFAS (PFOS in particular);
• eating food products such as meat, dairy and vegetables produced near locations where PFAS were used or made;
• eating food packaged in material that contains PFAS;
• accidently swallowing or breathing contaminated soil or dust;
• accidently swallowing residue or dust from consumer products such as stain-resistant carpeting and water-repellent clothing, and
• ingestion of residue and dust from PFAS-containing products.⁴

PFAS can enter a farm through water, soil additives, sewage sludge and synthetic chemicals such as pesticides. Then they are taken up by plants and livestock and inhaled by farmworkers and farmers. Eventually, they end up in food and animal waste.¹

A recent study found that consuming high amounts of tea, processed meats and food prepared outside of the home was associated with increased levels of PFAS in the body over time. Participants who consumed more tea, hot dogs and processed meats had higher levels of PFAS in their blood. Some foods were only associated with higher PFAS levels when they were prepared outside of the home. People who ate foods such as French fries or pizza prepared at restaurants typically showed increased levels of forever chemicals in their blood. The researchers suggested that the food packaging was the problem. The association between high levels of PFAS and tea intake could be linked to tea bags treated with forever chemicals – although more research is needed. Processed meats could be contaminated during the manufacturing process.^8,9 (This report produced by Toxic-Free Future includes a illustration of the toxic lifecycle of PFAS.) 

Switzerland’s Food Packaging Forum Foundation identified 68 PFAS “forever chemicals” in food packaging, including plastic, paper and coated metal packaging. Of the 68 identified PFAS compounds, 61 had been previously banned for use in food packaging. These researchers identified hazard data that was available for 57% of the PFAS compounds detected in food packaging. Based on their assessment, they concluded that “[t]he data and knowledge gaps presented here support international proposals to restrict PFASs as a group, including their use on food contact materials, to protect human and environmental health.”^10-11

On February 28, 2024, the US Food and Drug Administration (FDA) announced that “grease-proofing substances containing Per- and Polyfluoroalkyl Substances (PFAS) are no longer being sold by manufacturers for food contact use in the US market.”¹² This means that paper food packaging, including fast-food wrappers, microwave popcorn bags, and take-out pizza boxes, is no longer being made with certain kinds of grease-proofing PFAS. The voluntary phase-out eliminated the main source of exposure from our diets, according to the agency. However, there are lingering stocks of packaging that contain PFAS that could take months to be exhausted.³

New research published in Nature Geoscience found that PFAS are found in surface and groundwaters around the world at levels much higher than many international regulators allow. Scientists analyzed available data from more than 45,000 water samples around the world since 2004. Groundwater can be contaminated by PFAS from food and consumer products disposed of in landfills, manufacturing facilities and wastewater treatment plants (sewage treatment plants).^13,14

On April 10, 2024, the US Environmental Protection Agency (EPA) announced new standards for the regulation of PFAS chemicals in drinking water. The limits, known as maximum contaminant levels, or MCL, are the highest level of a contaminant allowed in drinking water. These limits consider health concerns and water treatment costs and feasibility. The new MCL requires water treatment plants to lower the amount of these chemicals to safer levels than currently exist in water systems.¹⁵ The new rules require municipal water systems to track and monitor the levels of PFAS, provide $1 billion in funding available to local governments to test and treat public water systems, and help owners of private wells address PFAS contamination. Water officials have five years to comply with the new limits.³ Public health advocates say the rules are an important first step, but they are limited in their impact on the broader PFAS crisis because they do not directly prevent further PFAS pollution or require the chemical industry to pay for cleanup through the “polluter pays principle.” Furthermore, the new rules address only six compounds, although about 15,000 PFAS exist, and the vast majority remain unregulated or unstudied. Drinking water represents only about 20% of human exposure, the EPA estimates, and diet may be a greater source of exposure.¹⁶

How to limit exposure to PFAS chemicals

Filter your tap water. Purchase a water filter for your tap. Reverse osmosis filters are the most effective. To remove a specific contaminant, such as PFAS, from drinking water, consumers should choose a water filtration device that is independently certified to remove a contaminant by a recognized lab.¹⁷ Reputable third-party testing organizations include NSF, formerly known as the National Sanitation Foundation (NSF), Water Quality Association (WQA), International Association of Plumbing & Mechanical Officials (IAPMO), UL Solutions, CSA Group, and Intertek (ETL). For a filter that can remove PFAS, look for one with the code NSF/ANSI 53 (or NSF/ANSI 58 for reverse osmosis systems), followed by the manufacturer’s claim that the product can remove PFAS.¹⁷ NSF has a list of recommended filters. The Environmental Working Group (EWG) has also published a guide with recommendations on the most effective water filters for reducing PFAS.

There are no standards for PFAS in bottled water.⁴

Save money, skip the plastic, and drink filtered tap water instead of bottled water. 

Food and food packaging. PFAS compounds can bioaccumulate in crops, fish, and livestock.¹ PFAS are used to make food packaging such as paper plates, bowls, bags, some plastic packaging, sandwich wrappers and other types of packaging to make them water- and oil-resistant. A recent study found higher PFAS levels in certain foods prepared in restaurants, including pizza and French fries^8,9 To reduce your exposure to PFAS:

• skip microwave popcorn – pop your own corn instead;
• limit consumption of highly processed meats (e.g. hotdogs);
• limit food packaged in paper board and paper-based takeout packaging, such as pizza;
• limit fast foods prepared at restaurants, such as pizza and French fries; and
• prepare home-cooked meals more often.^5,8

Use uncoated paper products and products made from materials other than paper, such as bamboo.¹ To store food – both at home and away from home – use glass instead of plastic containers.¹⁸ Compostable containers, although plastic free, may not be PFAS free.^19,20 For more information, visit Toxic-Free Future.

Cookware. If a pot or pan becomes damaged, consider a replacement. Through repeated use, non-stick cookware begins to scratch and chip. Switch to kitchen cookware free from PFAS, including stainless steel, cast iron, and glass. Carefully choose cookware. Beware of nonstick cookware that claims it’s free of PFOA, a PFAS that has been phased out. The cookware may contain just-as-toxic replacement chemicals.^5,21

Clothing, textiles and dust. Purchase clothing items from companies that have made commitments to not use PFAS in their products. Avoid waterproofing and stain-proofing treatments, unless advertised as free of PFAS. Vacuum frequently using a vacuum fitted with a HEPA filter to eliminate household dust that may contain PFAS. Opening windows can help filter out dust as well.^3-5

While these are important steps that consumers can take to limit their exposure to PFAS, some scientists believe they aren’t enough to control PFAS contamination. Their pervasiveness in the environment makes it impossible to avoid exposure, according to Dr. Carmen Messerlian, a Professor of Reproductive Environmental Epidemiology at Harvard’s T.H. Chan School of Public Health, who studies PFAS:

Even someone like me, a scientist and a mother who cares about human health, can’t avoid PFAS chemicals. I can chip away and make choices in my day that reduce my exposure. But I’m looking at my fridge right now, and I can tell you most of my foods have come in contact with PFAS. We should regulate the entire class of chemicals and stop companies from manufacturing them to begin with, rather than try to regulate how much is in our water.³

Conclusion

Per-and polyfluoroalkyl substances (PFAS) are present in a wide range of consumer products and in water and food supplies. They bioaccumulate in our bodies over time and may be associated with serious health problems. By taking the above actions, you can reduce your exposure to PFAS. However, there is a need for ongoing monitoring, improved testing, and enhanced government regulation to address the widespread occurrence of PFAS contamination in the environment. 

Photos by Jocelyn Fitzgerald, used with permission

References:

1. The Foodprint of PFAS. A Foodprint Report. Foodprint, September 2023. (Updated November 2023). 
2. Gore AC, LaMerrill MA, Patisaul H, Sargis RM. Endocrine Disrupting Chemicals: Threats to Human Health. Pesticides, Plastics, Forever Chemicals and Beyond. Endocrine Society and International Pollutants Elimination Network (IPEN). Washington DC: Endocrine Society. February 26, 2024; p. vi.   
3. Boudreau C, McFall-Johnson M. Your drinking water could contain fewer hazardous ‘forever chemicals’ under new federal rules. Business Insider. April 10, 2024. 
4. Agency for Toxic Substances and Disease Registry (ATSDR), Centers for Disease Control and Prevention (CDC). PFAS and Your Health. Last Updated on January 18, 2024. Atlanta, GA: Centers for Disease and Control and Prevention (CDC). 
5. Persellin K, Andrews D. ‘Forever chemicals’: Top 3 ways to lower your exposure. Environmental Working Group. February 14, 2024. 
6. Guidance on PFAS Exposure, Testing, and Clinical Follow-Up. Consensus Study Report. Washington DC: National Academies of Sciences, Engineering, and Medicine; 2022. 
7. Belcher S. PFAS Chemicals: EDCs Contaminating Our Water and Food Supply. Washington DC: Endocrine Society. Undated. 
8. Hampson HE, Costello E, Walker DI. Associations of dietary intake and longitudinal measures of per- and polyfluoroalkyl substances (PFAS) in predominantly Hispanic young Adults: A multicohort study. Environmental International, 2024;185:108454. 
9. Tea bags, takeaways and hot dogs linked to high levels of forever chemicals, American study finds. Euronews Green, February 21, 2024.
10. Phelps DW, Parkinson LV, Boucher JM, et al. Per- and polyfluoroalkyl substances in food packaging: Migration, toxicity, and management strategies. Environ. Sci. Technol. 2024;58(13):5670–5684.
11. Hemingway Jaynes, C. 68 PFAS ‘forever chemicals’ found by scientists in food packaging worldwide. EcoWatch. March 21, 2024. 
12. US FDA. FDA Announces PFAS Used in Grease-Proofing Agents for Food Packaging No Longer Being Sold in the U.S. February 28, 2024. 
13. Ackerman Grunfeld, D., Gilbert, D., Hou, J. et al. Underestimated burden of per- and polyfluoroalkyl substances in global surface waters and groundwaters. Nature Geoscience, 2024.
14. LaMotte S. Toxic ‘forever’ chemicals found in excessive levels in global groundwater, study says. CNN. April 9, 2024. 
15. Amarelo M. EPA sets bold new limits on ‘forever chemicals’ in drinking water. Environmental Working Group. April 10, 2024.
16. Perkins T. EPA has limited six ‘forever chemicals’ in drinking water – but there are 15,000. The Guardian April 11, 2024.
17. Flamer K. How to Get PFAS Out of Your Drinking Water. Consumer Reports April 10, 2024. 
18. 10 Things You Can Do About Toxic PFAS Chemicals. Clean Water Action. Undated.
19. University of Toronto. New study finds toxic PFAS ‘forever chemicals’ in Canadian fast-food packaging. Phys.Org. March 28, 2023. 
20. Schwartz-Narbonne H, Xia, C, Shalin A. Per- and polyfluoroalkyl substances in Canadian fast food packaging. Environmental Science & Technology Letters, 2023;10:343-349. 
21. Boston’s Children’s Hospital. Pediatric Environmental Health Specialty Unit (PEHSU) PFAS Food Factsheet. Boston, MA; February 2024.