Is it safe to use a crockpot liner bag?
Avoid for routine use. Crockpot liners put hot food in plastic for hours to save cleanup time.
What's actually in it
Crockpot liner bags are made from heat-tolerant plastic film. They keep food from sticking to the ceramic insert, but they also create hours of warm food contact with plastic.
The liner is optional. That matters. If the only benefit is less scrubbing, it is not a great trade for regular family meals.
What the research says
A 2025 study in J Agric Food Chem found polypropylene food containers released nanoplastics and microplastics into water, with higher release after 90 degrees C rinsing than room-temperature rinsing.
A 2021 study in Food Chem Toxicol assessed migration from food-contact plastics using food simulants, including water, 4% acetic acid, and n-heptane. The study found low concern under tested regulatory conditions, but it confirms why food type, temperature, and contact conditions matter.
Skip the liner for routine cooking. Cook directly in the crock, soak it after dinner, and store leftovers in glass. If cleanup is the problem, use parchment only where it makes sense and keep it away from wet, oily, all-day recipes.
The research at a glance
| Study | Journal | Year |
|---|---|---|
| Release of Nanoplastics from Polypropylene Food Containers into Hot and Cold Water. | J Agric Food Chem | 2025 |
| Migration of substances from food contact plastic materials into foodstuff and their implications for human exposure. | Food Chem Toxicol | 2021 |