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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.