Few things save a person more time and energy in the kitchen than making their trusty slow cooker a series regular during meal prep. Just pop a handful of ingredients into the pot at the start of your day and poof—you've got a delicious dinner ready for you once you're off the clock. Piece of cake. The cleanup afterward, though? Not so much.

Enter single-use slow-cooker liners, which slash the grind of post-meal scrubbing and stain removal from your to-do list. "Instead of scrubbing the pot, you just throw away the liner," says Janilyn Hutchings, a certified food safety professional at StateFoodSafety. "There may be some moisture left in the pot from the cooking process, but all you need to do is wipe it out with a clean cloth or paper towel."

Still, now that we're well-versed in the health concerns that surround using plastic during the cooking process (specifically, the risk of chemicals from the plastic leaching into your food), what does this mean for how safe disposable Crock-Pot liners are?

Slow-cooker liners are typically made of a heavy-duty nylon resin that's built to resist high heat (around 400°F, depending on the brand). They're also manufactured to be durable enough not to melt or tear while in use.

Plastic products, like Crock-Pot liners, are usually some combination of a polymer resin (the raw material for manufacturing plastic products) and additives that are mixed in to enhance the performance of the product itself, according to the Pacific Northwest Pollution Prevention Resource Center. In the case of slow-cooker liners, they likely contain additives that allow them to withstand extended periods of high heat and food contact.

Unfortunately, the exact resin and additive composition used to manufacture Crock-Pot liners depends on the brand (and is unavailable to the public), so there's practically no data indicating whether specific parts of the composition might leach into food during the cooking process.

The chemical compound found in various types of plastic food containers that raises the most eyebrows is bisphenol A (BPA), with research suggesting a possible link between BPA and increased blood pressure, type 2 diabetes and cardiovascular disease, among other health issues, according to the Mayo Clinic. And BPA substitutes, such as BPS, might not be any safer.

"Currently, the official stance of the U.S. Food and Drug Administration is the amount of BPA currently contained in food containers is safe," says Hutchings. "However, the European Food Safety Authority recently released a new scientific opinion on the risks of even small amounts of BPA, leading some groups in the United States to petition the FDA to impose stricter limits on the amount of BPA allowed in food containers and packaging."

Because research on the compounds found in plastics that come into contact with food are ongoing (there are hundreds of chemicals currently considered safe food contact substances), it's hard to give a definitive answer on exactly how safe slow-cooker liners are, Hutchings says.

Don't worry, there's a but: To be used in food contact products, like Crock-Pot liners, all resins and additives used not only must be authorized by the FDA, but also must stay within the limitations or specifications for their intended use, such as allowed concentrations of each additive in the final product and the temperatures during use that are acceptable.

This means that so long as the liners you buy are FDA-approved and free of BPA and BPA substitutes (Reynolds Kitchens Slow Cooker Liners and Crock-Pot Slow Cooker Liners are two excellent—and popular—picks), you'll help to minimize any potential chemicals leaching into the foods you cook as much as possible.