Are there “Forever Chemicals” in Your Kitchen Counter?

By Hannah Ray | January 18, 2022

What are your favorite seasonings for food - salt, pepper, ketchup, parm? How about a sprinkling of PFAS?

Per- and polyfluoroalkyl substances, or PFAS, are a common ingredient in kitchen countertop sealers. This is concerning for three main reasons:

Well-studied PFAS have been linked to serious health harm.
PFAS might migrate from a food preparation surface to the food itself, or to household dust, leading to human exposure.
PFAS can contaminate the environment and can harm human health before and after they even enter a home, during product manufacturing and in their eventual disposal.

But we want to share a bit of good news: At least one company makes a high-performance sealer that's fluorine-free. How do we know it's safer, and how did the company find this solution? Read on for more details.

What are PFAS?

PFAS, sometimes referred to as highly fluorinated chemicals or PFCs, are used in consumer products and industrial applications because of their oil-, stain-, and water-repellent properties. Chemicals in this class include more than 4000 related compounds (including PFOA and PFOS, which are no longer manufactured in the U.S.). Due to the very strong bonds between their carbon and fluorine atoms, PFAS persist in the environment and can bioaccumulate. Well-studied PFAS have been linked to serious health harm. Populations with the highest exposure are workers in PFAS manufacturing or processing plants, followed by communities drinking PFAS-contaminated water.¹ But all of us are affected: PFAS have been detected at some level in 99% of people worldwide.

PFAS and Food Contact Surfaces

Humans encounter PFAS through contaminated food, drinking water, air and dust. Products in our homes and workplaces that contain these chemicals can contribute to our exposure. Diet is a major PFAS exposure pathway for the general population: the chemicals can build up in the plants and animals we eat, contaminate our food during processing, and migrate from surfaces that contact our food.

The degree to which PFAS-treated countertops and similar surfaces contribute to human exposure is not known, but it’s good to be cautious. According to Tom Neltner of the Environmental Defense Fund, the words “food safe” on a bottle of cleaner or sealer are marketing terms and not scientific.² As public awareness increases about PFAS and food contact surfaces, state lawmakers, including in California, Washington, and New York, have banned the use of PFAS in food packaging. Many fast-food companies, grocery stores, and large institutional purchasers have voluntarily phased out PFAS in oil- and grease-proof coatings on takeout containers. And in a recent letter to manufacturers, the FDA warned against using improper fluorination of polyethylene plastic food containers.

But what other PFAS-treated surfaces does food touch? Like your kitchen counter?

PFAS and Countertop Sealers

Over the years, kitchen countertop materials have ranged from plastic laminates, to tile and grout, to concrete, engineered stone, granite, quartz, steel, copper, and more. Stone slab countertops, especially granite, have dominated the market for several decades. Countertop materials with high porosity - such as granite, concrete, or the grout between tiles - must be sealed periodically to prevent bacteria from growing in the pores. Sealers for countertops and grouts usually contain fluoropolymers - a type of PFAS - because they confer oil- and water-repellency.

It’s not news that PFAS are used in countertop sealers. The Healthy Building Network (HBN) in 2016 released a common product profile for countertop sealers noting fluoropolymers as a common ingredient. HBN cites an EPA study from 2009 that found sealers for stone, tile, and wood to contain a high level of perfluorocarboxylic acids (PFCAs).³ Because of the health concerns associated with PFCAs, the HBN HomeFree countertop selection guide recommends choosing dense slab surfaces such as porcelain or engineered stone that do not require sealing.

That’s helpful information for a new building or a kitchen remodel. But what if you already have a porous countertop that needs resealing, and you want to avoid PFAS? Here’s our good news!

A PFAS-Free Choice

Our lab tests⁴ have determined that at least one kitchen countertop sealer, TriNova Granite Sealer, is PFAS-free. This product also ranked well in recent online reviews. That’s good news for cooks and eaters. We talked with Trinova to learn more.

TriNova, owned by Gold Eagle, makes cleaners and protectant products for stone, metal, leather, glass, and other surfaces. They use healthier ingredients, and also comply with the recent California ingredient disclosure law by providing chemical ingredient information online for all of their products.⁵ TriNova Granite Sealer’s ingredient list confirms that it is fluorine-free.

TriNova R&D Manager David Gutierrez thinks about the safety of his customers (families and kids) when choosing ingredients. The original formulation for their sealer contained ingredients listed as cancer-causing and/or reproductive toxicants according to California Proposition 65. Customers didn’t want harmful substances touching their food. To choose healthier ingredients, his team used the EPA’s Safer Choice Ingredient List, as well as the GreenSeal Standard, as guiding resources.

Gutierrez shared the following advice for others developing healthier products: “Look carefully at the chemical profile of each ingredient - biodegradability, toxicity, skin irritation, etc. - and choose the most benign substances. Whatever you choose needs to be safe enough for your kids. Sometimes this means that the raw materials are more expensive, but it’s important to prioritize safer chemistry and excellent performance.”

Chemical Transparency: See for Yourself!

By sharing the full list of ingredients for its products with the public and across supply chains, TriNova is practicing chemical transparency. Widespread adoption of this excellent practice is critical to promoting the use of safer chemicals and products across industries, because it allows stakeholders at all levels to make informed decisions about chemical hazards.

Let’s take a closer look at what we can do with this information. The ingredient list for TriNova Granite Sealer is copied below. How do we find out the hazard profile of each ingredient?

Water
- Intentional Ingredient
- 7732-18-5
- Carrier
Silicone Microemulsion
- Intentional Ingredient
- CBI
- Surface Coating
5-chloro-2-methyl-isothiazolin-3-one
- Intentional Ingredient
- 26172-55-4
- Active Preservative
2-methyl-4-isothiazolin-3-one
- Intentional Ingredient
- 2682-20-4
- Active Preservative
Magnesium Chloride
- Nonfunctional Ingredient
- 7786-30-3
- Impurity

We shared the full list of ingredients with ChemForward - a non-profit organization that is building a globally harmonized repository of chemical hazard assessments focused on safer alternatives.

ChemForward’s database had chemical hazard data on all ingredients in the formulation except for one, which was considered Confidential Business Information (CBI). All rated ingredients scored C or higher on ChemForward’s hazard ratings, which qualifies them as safer alternatives. A summary of the ChemForward hazard ratings and implications are depicted in the table.⁶

ChemFORWARD offers ingredient intelligence reports to manufacturers.⁷ Such a report identifies hotspots (chemical ingredients of concern) or data gaps in an ingredient’s chemical hazard profile. If everything checks out, ChemFORWARD can recommend certification pathways - there are many, including Cradle to Cradle, Safer Choice, GreenSeal, or GreenScreen.⁸

In the case of TriNova Granite Sealer, the lone CBI ingredient (the silicone microemulsion) presents a data gap. Although silicone is generally understood to be safer than PFAS, silicone can still contain different chemicals of concern, depending on how it was made.⁹ It would be helpful to confirm the safety of the ingredient with a third-party hazard assessment. To do this, TriNova could confidentially work with one of ChemFORWARD’s approved third-party assessors to commission a chemical hazard assessment that would then populate the shared repository.

Conclusions:

Though we can understand why PFAS are used in countertop sealers, effective, less worrisome alternatives are available. We are looking for additional countertop sealers to add to our PFAS-Free page. Check out our Eligibility Criteria and please get in touch if you can suggest additions.

The following actions by product purchasers, manufacturers, and government agencies would help reduce the use of PFAS in sealers.

Guidance for purchasers:

Prefer products that provide full ingredient disclosure. Search for the product name and ingredients, or "CA SB 258" on their website. Many manufacturers of these products are required to disclose all ingredients online.
Avoid PFAS chemicals - often they'll have "fluor" in the name, or will appear on an authoritative list of PFAS, like the EPA's Comptox PFAS Master list.
If you can't find the ingredient list, contact the manufacturer and ask if they use fluoropolymers or other PFAS in their formulations.

Guidance for manufacturers:

Begin formulating safer, PFAS-free products.
Innovate safer alternatives using resources like EPA's Safer Choice Ingredient List, Cradle to Cradle, and GreenSeal.
Get to know what PFAS are, track them in your supply chain, and stay informed about legislative and regulatory actions around PFAS at the state, federal and international levels.
Comply with California's Cleaning Product Right to Know Act and fully disclose the ingredients in your products.

Government actions:

Government agencies have influence not only through regulation, but also through purchasing agreements.

Restrict PFAS-containing products that are not essential.
Require manufacturers to disclose which PFAS they are using and where.
Use purchasing power to require manufacturers to disclose chemical ingredients, and purchase products without PFAS.

Notes

1. Sunderland, E.M., Hu, X.C., Dassuncao, C. et al. A review of the pathways of human exposure to poly- and perfluoroalkyl substances (PFASs) and present understanding of health effects. J Expo Sci Environ Epidemiol 29, 131–147 (2019). https://doi.org/10.1038/s41370-018-0094-1

2. If the intended use of a surface is to contact food and a chemical “may reasonably be expected to result, directly or indirectly, either in their becoming a component of food”, then either a food contact substance notice or a food additive petition needs to be submitted to FDA. However, the company can also self-certify the chemical’s use as Generally Recognized as Safe and choose not to voluntarily notify the FDA. When shopping for safer products, look for certifications such as the Safer Choice Standard, which requires full chemical disclosure and chemical hazard assessments for each ingredient, or Cradle to Cradle, which restricts all PFAS substances.

3. To incorporate the fluoropolymers and other ingredients into a homogeneous, sprayable solution, additives that may contain PFAS, such as fluorinated surfactants, may be needed. The EPA/Roache study detected PFCAs in 2009, but formulations since then may have changed; we have found evidence that they now use perfluoroalkane sulfonic acids. See this 2017 patent for examples. The technical data sheet for one of the surfactants notes that it contains perfluorobutanesulfonic acid (PFBS).

4. The method used to measure total fluorine is described in Schaider, L.A. et al., Environ Sci Technol Lett. 4(3): 105–111 (2017). The countertop sealer liquid was purchased online, poured into a centrifuge tube and mailed to Professor Graham Peaslee’s lab at the University of Notre Dame for total fluorine measurements using the PIGE method. Liquid samples were dropped on fluorine-free tissue paper, allowed to dry, and the tissue paper was mounted in front of the PIGE apparatus for measurement. The limit of detection (LOD) was 40ppm. The result for this product came back as less than the LOD.

5. TriNova and its sister brand 303 use the requirements set by the CA SB 258 “Cleaning Product Right to Know Act” from 2017 and the New York “Cleansing Product Information Disclosure Program” to guide how they disclose their ingredients online.

6. Because chemical hazard assessors own their assessments, we cannot divulge here the specific score of each of the chemical ingredients. However, interested individuals and companies can work with ChemFORWARD if they’d like more specific information.

7. To create an ingredient intelligence report, ChemFORWARD needs full ingredient disclosure, including the concentration threshold or detection level.

8. To obtain a certification, a manufacturer would need to report all components down to a concentration of 100ppm, including both functional and nonfunctional intentional additions, residuals and impurities.

9. Some chemicals of concern commonly used in the manufacture of silicone include D4 and D5 cyclosiloxanes. TriNova proactively works with its suppliers to be sure that D4 and D5 are not used as precursors in their silicone microemulsion, or at any stage in the manufacturing process. TriNova’s ingredient supplier has staff toxicologists and regulatory specialists who work to ensure that the material is non-hazardous.

Acknowledgements

Many thanks to the following people for their helpful contributions to this blog post!

Dr. Lauren Heine and Stacy Glass at ChemFORWARD provided an ingredient intelligence report for the sealer product. ChemFORWARD is a non-profit value chain collaboration populating a globally harmonized repository of chemical hazard assessments focused on safer alternatives.
Tom Neltner, Senior Director, Safer Chemicals at Environmental Defense Fund interpreted the FDA’s regulations for food contact surfaces.
David Gutierrez at Gold Eagle shared his advice on best practices to create safer formulations.