By Jen Dickman, Erika Schreder, and Nancy Uding

New testing indicates major fast-food chains are still serving up PFAS (per- and polyfluoroalkyl substances) with some of their most popular takeout foods, despite increasing consumer demand and legislative action to phase out the use of toxic PFAS chemicals.

The testing included a total of 38 food packaging samples from 3 states in 16 locations and 6 fast-food chains. Nine out of the 38 samples were replicates, resulting in a total of 29 unique sample items for comparison. The testing of total fluorine to screen for the presence of PFAS was performed by an independent laboratory in February 2020. The study was conducted by the Mind the Store campaign and Toxic-Free Future.

Nearly half of all food packaging samples tested positive for fluorine above the screening level, including for fast-food favorites such as McDonald’s Big Mac, Burger King’s Whopper, and Sweetgreen’s salads and warm bowls. Sweetgreen recently announced it is phasing PFAS out of all of its bowls by the end of 2020 and has already introduced PFAS-free bowls in one market. All bags we tested that are used for sides such as chicken nuggets, fries, and cookies also tested positive. At the salad chains, 100% of all molded fiber packaging we tested was above the screening level. The thick paper packaging, intended to be compostable, is used by many chains as an alternative to plastic.

PFAS are used to make materials grease- and water-resistant. They are commonly found in products such as apparel, carpeting, upholstery, and food packaging. These “forever chemicals” are dangerous to humans and wildlife and have contaminated the drinking water of millions of people across the U.S. Exposure to PFAS is an especially high concern in the context of COVID-19 since they are linked to suppression of the immune system as well as chronic conditions that increase the severity of COVID-19. The Food and Drug Administration (FDA) has prohibited the use of only a small number of chemicals within the PFAS class in food packaging but continues to allow the use of many others, despite the risks posed. During the past few years, intense scrutiny on the dangers of PFAS has led to PFAS food packaging bans in San Francisco and Berkeley and states including Washington and Maine. Outside the U.S., Denmark enacted a ban on PFAS in cardboard and paper food packaging, which goes into effect July 1, 2020. Major retailers and restaurants including Panera Bread, Taco Bell, Chipotle, and Whole Foods Market are also moving away from PFAS.

But this newest study reveals work remains to ensure major burger and salad chains use safer, readily available PFAS-free packaging.

The one bit of good news? Burger chains seem to have largely switched to PFAS-free paper for their paper-wrapped burgers. Only one of seven burger wrappers tested above a screening level for fluorine, suggesting PFAS treatment. This is an encouraging sign that food chains are finding and using safer, healthier alternatives.

The nitty-gritty: what we found at health-conscious and burger chains

The Mind the Store campaign and Toxic-Free Future collected and tested packaging for burgers, sandwiches, chicken nuggets, cookies, and French fries or other fried sides from the nation’s three top burger chains: Burger King, McDonald’s, and Wendy’s. We also collected and tested packaging from three top health-minded chains: Cava, Freshii, and Sweetgreen.

We found that as top burger chains churn out meal after meal, they may be making a significant contribution to the PFAS pollution crisis. At least one packaging item from every burger chain appeared to be PFAS-treated:

  • Six of seven burger and sandwich wrappers were likely not PFAS-treated. However, the wrapper on Burger King’s iconic Whopper and the thin cardboard container for McDonald’s popular Big Mac tested above the screening level for fluorine.
  • At Burger King, McDonald’s, and Wendy’s, all five of the tested paper bags for fried foods and desserts tested above the screening level for fluorine. These included a French fry bag from McDonald’s, a chicken nuggets bag from Burger King, and cookie bags from Burger King, McDonald’s, and Wendy’s.
  • Interestingly, in many cases, the chains use packaging for some fried foods that appears to be PFAS-free by providing a different material. Paperboard cartons or clamshells for fries, tots, or fried chicken pieces sold at the burger chains all tested below the screening level.

a. McDonald’s small fry bag
b. McDonald’s Big Mac clamshell
c. Burger King Whopper wrapper
d. Burger King chicken nugget bag
e. McDonald’s cookie bag
f. Burger King cookie bag
g. Wendy’s cookie bag

Change is possible - 67% of tested packaging from burger chains was PFAS-free

We found that while health-conscious customers might feel good about getting a full serving of veggies, the packaging it comes in is anything but healthy. Nearly all samples tested from Cava, Freshii, and Sweetgreen appeared to be PFAS-treated:

  • Every single molded fiber container tested above the screening level for fluorine, suggesting PFAS treatment. These containers actually showed the highest levels of fluorine out of all items tested in this study. Molded fiber containers tested included the Freshii salad bowl, the Sweetgreen bowls for salads and warm bowls, and the Cava bowl for greens and/or grains as well as the Cava compartmentalized tray for kids’ meals. While molded fiber packaging has been prized for its compostability, our testing strongly suggests it is treated with PFAS. To its credit, Sweetgreen announced in early March it is phasing PFAS out of its bowls by the end of 2020, replacing them with a PFAS-free compostable bowl.
  • Freshii and Cava also serve sandwiches and sides in paper packaging. Freshii’s wrapper for wraps came back as below the screening level. However, a Cava wrapper for pita sandwiches and a Cava paper bag for pita chips tested above the screening level for fluorine, suggesting PFAS treatment.

a. Freshii bowl
b. Cava kids’ meal tray
c. Cava bowl
d. sweetgreen salad bowl
e. sweetgreen warm bowl
f. Cava pita chip bag
g. Cava wrapper for pita sandwich or mini pita

Nearly 90% of tested packaging from health-conscious chains was positive for fluorine

Nearly half of tested food packaging items likely contained PFAS

To learn more: Click here to download the full list of results by individual item, including the chain type, chain name, state of collection, packaging category, type of food the item holds, and packaging description.

Food packaging with PFAS should not go in the compost bin

The nation’s two major compostability certification organizations (Biodegradable Products Institute (BPI) and Compost Manufacturing Alliance (CMA)) have stopped certifying new items as compostable if their ingredients include PFAS or they contain more than 100 ppm total fluorine. Products on BPI’s current certified list already meet these restrictions and all products on CMA’s list will meet them beginning in 2021. It is notable that our testing found 14 unique food packaging items with levels of fluorine over 100 ppm, even though some chains treat them as compostable. Restaurants that want their packaging to be acceptable for composting need to take a close look at the packaging they use and make sure it’s free of PFAS.

The PFAS crisis

PFAS have become global pollutants that threaten the health of people and wildlife. PFAS are notorious as drinking water contaminants from industrial releases, for their use in firefighting foam, and for their use in a myriad of other products. Today, millions of U.S. residents are drinking PFAS-contaminated water and nearly 100% are carrying a body burden of PFAS. With their remarkable persistence and mobility in the environment, PFAS move through soil to drinking water.

When PFAS are used in consumer products, they can migrate out to contaminate household dust and air. Testing of packaging from a number of fast-food chains published in 2017 found that the use of PFAS-treated wrappers and bags was widespread, with 46% of papers testing positive for fluorine. PFAS-treated paper food packaging and wrappers can contaminate food that touches them, and newer forms of PFAS migrate more readily into food than older forms. PFAS from food wrappers may also end up in people. A 2019 study analyzed data from a national survey on levels of PFAS in blood and in food consumed between 2003 and 2014 and found that eating microwave popcorn was associated with higher concentrations of PFAS in blood. Once the food is gone, the packaging goes to the garbage or into municipal compost. Either way, PFAS chemicals from a discarded bowl, wrapper or bag can make their way back to people through drinking water, food, and air. Food crops and gardens can become contaminated with PFAS-containing compost, as shown from research demonstrating plants taking up PFAS from soil.

In March of 2020, a consortium of scientists published a new scientific statement sounding the alarm about toxic chemicals such as PFAS in food packaging. Read it here.

Exposure to certain PFAS has been linked to a number of serious adverse health effects: kidney and testicular cancer, thyroid disease, decreased fertility, hormone disruption, pregnancy-induced hypertension/pre-eclampsia, liver damage, increased cholesterol, decreased antibody response to vaccines, increased risk of asthma diagnosis, changes in nervous system development, and lower birth weights.

While FDA worked with industry to remove certain older forms of PFAS from food-contact materials and recently announced that manufacturers have voluntarily agreed to phase out an additional subset of current-use PFAS from these materials, the agency still allows the use of other PFAS. This new announcement follows recent research by FDA scientists showing current-use PFAS are bioaccumulative and more toxic than FDA previously acknowledged. This research adds to the case that PFAS should be regulated as an entire class due to their high persistence, potential for accumulation, and hazards.

For more in-depth information on the types of PFAS commonly found in food packaging, see “The Problem with PFAS in Food Packaging and Contact Materials” in our earlier report Take Out Toxics: PFAS Chemicals in Food Packaging.

States and retailers stepping up to ban PFAS in food packaging

In the absence of federal leadership to protect health and the environment, states and retailers are stepping up. Panera Bread, Taco Bell, Whole Foods Market, Trader Joe’s, Ahold Delhaize, Albertsons, and Sweetgreen have announced steps to reduce or eliminate PFAS in food packaging.

Washington State passed the first state measure to restrict PFAS in paper food packaging in 2018, and Maine passed restrictions on PFAS as well as phthalates in food packaging in 2019. As of January 2020, bans in San Francisco and Berkeley have gone into effect. In all these cases, the bans cover the entire class of PFAS. Also this year, several states are considering legislation to ban PFAS in food packaging (see the Safer States Bill Tracker for more information).

Responding to public demand, Congress has initiated action on PFAS in food containers and cookware with the introduction of the Keep Food Containers Safe from PFAS Act, sponsored by U.S. Representative Debbie Dingell and cosponsored by U.S. Representative Jan Schakowsky.

PFAS-free food packaging alternatives

The results show that while some restaurant chains are using packaging that is likely PFAS-treated for certain foods, fluorine-free packaging for the same types of food is also in wide use.

  • In some cases, fluorine-free versions of the same packaging are available, such as burger or sandwich wrappers.
  • In other cases, a different type of packaging can be used. For example, instead of using cardboard clamshells to package burgers (one of one tested above the screening level) or using paper bags for greasy fries, other fried items, or desserts (six of six tested above the screening level), paperboard clamshells or other paper cartons free of fluorine can be used.

Food packaging manufacturers are responding to the rapidly growing market demand for fluorine-free products, making many PFAS-free products readily available.  Paper manufacturers that make and sell fluorine-free food service papers include Ahlstrom-Munksjo (Grease-Gard Fluoro-Free and Para-Free Wax Alternative papers), Nordic Paper (Natural Greaseproof Papers), Seaman Paper (EcoLite stock papers), Twin Rivers (Acadia Eco-Barrier papers), Domtar, and Delfort (Thin-Barrier Eco Paper).

Manufacturers of fluorine-free single-use food serviceware and packaging products that are on the market or will soon reach the market include Biodegradable Food Service, Dart Solo, Eco-Products, Footprint, Georgia Pacific/Dixie (Ultra Pathways), Huhtamaki, If You Care, Stalk Market, Transitions2earth, Vegware, WestRock Fold-Pak, Novolex, Pactiv, Inline Packaging, and World Centric.

Reusable food serviceware also remains widely available and is the preferred option.


Restaurant chains and other food retailers should do the following:

  1. Adopt and implement a public policy with clear quantifiable goals and timelines for reducing and eliminating PFAS in all food contact materials in restaurants and supply chains.
  2. Ensure substitutes are safer, at a minimum free of any GreenScreen Benchmark 1 chemicals.
  3. FDA should withdraw its approvals for all PFAS in food contact materials and not approve any new PFAS.
  4. Publicly report on progress and announce when the food contact materials are PFAS-free.
  5. Develop a comprehensive safer chemicals policy to reduce and eliminate other toxic chemicals, such as ortho-phthalates, in food contact materials and other products.

Other parties also have a role to play:

  1. States and local governments should ban PFAS in food contact materials, ensure safer alternatives, and leverage their institutional purchasing power to buy safer PFAS-free food serviceware.
  2. Congress should pass the Keep Food Containers Safe from PFAS Act.
  3. FDA should withdraw its approvals for PFAS in food contact materials and not approve any new PFAS.
  4. Commercial composting facilities should accept only food packaging that is certified PFAS-free (i.e. certified by the Biodegradable Products Institute or the Compost Manufacturing Alliance).
  5. Individuals should call on food retailers and elected officials to ban PFAS in food contact materials. Take action now to tell McDonald’s to stop using PFAS!


Because PFAS are such a large and complex class, total fluorine is typically used as a screening method for PFAS treatment. In the case of food packaging, it is the method used by compostability certifiers to exclude PFAS. In this study, we sampled food packaging for testing from 16 locations of the top three burger and three top health-conscious restaurant chains based on whether the packaging held standard or popular menu items that likely used grease- or oil-resistant packaging. We also collected some of the same wrappers or bowls from different locations of the same chain to test for regional variation in key items (these samples are not counted separately in the results presented in Table 1 above, which only shows the number of unique items). Samples were collected in January 2020 at chains in and around New York City, Washington, DC, and Seattle, WA. We commissioned total fluorine analysis of 38 total samples of food contact materials at Galbraith Laboratories (Knoxville, TN) using combustion with ion-selective electrode to determine whether the fluorine levels suggested likely PFAS treatment.

For more details on the methodology, click here.


Thanks go to Galbraith Laboratories, Inc. for conducting the total fluorine testing on our samples, and to Dr. Laurel Schaider of Silent Spring Institute and Dr. Gillian Miller of the Ecology Center for reviewing this material. Thanks also to Beth Kemler and Mike Schade of Safer Chemicals, Healthy Families and the Mind the Store campaign for their assistance in collecting samples and review of this article, and Laurie Valeriano of Toxic-Free Future for her review of this article.

Jen Dickman is the Senior Program Associate for Safer Chemicals, Healthy Families and the Mind the Store campaign. Erika Schreder is the Science Director of Toxic-Free Future. Nancy Uding is the Program Director of Toxic-Free Future.