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Toxic Chemicals in Dental Floss graphicIf you’re a faithful flosser, you’re probably getting regular props from your dentist for your squeaky-clean teeth. That’s because flossing is considered to be one of the hallmarks of superior oral hygiene. Dentists consider flossing an important tool to fight tooth decay and gum disease.

But have you ever considered what’s in your floss and how that may impact more than just your mouth? If you haven’t, Made Safe thinks it’s time that you should. After all, what goes into your mouth has direct access to your body and bloodstream.

Harmful Substances to Avoid in Dental Floss

PFAS (Per- and Polyfluoroalkyl Substances): Dental floss can be coated with substances from a chemical family called PFAS or Per-and Polyfluoroalkyl Substances. Given the topic, you could say they’re quite a mouthful.

These substances, of which there are more than 3,000 in the marketplace, are commonly used to make everyday household items stain resistant, nonstick, and/or water resistant. They’re sometimes found in clothing, sports gear and equipment, mattresses, furniture, cosmetics, carpets, cookware, and linens. A lesser known fact is that these chemicals are often used to make dental floss glide smoothly between teeth.

The problem with these substances is that they do not easily break down in the environment or in the body. Many PFASs have the tendency to bioaccumulate, which means that their concentration within the body increases over time. In conjunction with not being easily broken down in the body, it means that these substances like to stick around inside our bodies, as well as the bodies of animals.

Many PFASs also have the capability to elicit a range of toxic effects like adverse effects on sexual function and fertility, hormone disrupting capabilities, cancer, developmental and reproductive toxicity, and more.

While there needs to be more study on PFASs and the effects that might be associated with their exposure, what research does exist suggests that avoiding these substances is prudent.

Plastic: Floss is often made from plastic – including virgin plastic and recycled plastic. Plastic can contain toxic chemicals that can impact our health. While there are many chemicals of concern in plastic, two of the primary concerns include phthalates and bisphenols (like BPA).

Many phthalates, which soften plastics to make them less brittle, are linked to a wide range of endocrine disrupting impacts. Bisphenols are plastic polymers, meaning they make up the plastic itself. Some bisphenols have also been linked to endocrine disruption.

Plastics are also problematic for the environment as they don’t readily break down. Instead, they just break into smaller and smaller pieces, contributing to pollution of waterways and our oceans, which impacts marine life.

Flavor: Dental floss can be flavored with many substances, including undisclosed and unknown ingredients. For example, artificial flavors may be any of approximately 700 FDA-approved flavorings/additives. But they can also be any of more than 2,000 other chemicals regulated by the Flavor and Extract Manufacturers Association of the U.S. Because of loose definitions, even natural flavors can include synthetic ingredients like carriers, solvents, and preservatives.

Harmful flavor formulas are a back door for many substances to make their way into products including some floss. Because they’re protected under federal law’s classification of trade secrets, flavor formulations can go undisclosed, simply listed as “flavor” on packaging. Without full disclosure on the label, it’s impossible for a consumer to know what ingredients might be within the formulation.

For more details on “flavor,” read up on our Made Safe Flavor Fact Sheet here.

Tips for Safer Dental Floss

  • Forego the uncoated floss, if appropriate for your teeth and gums.
  • If shopping for coated floss, opt for a coating made of beeswax.
  • Avoid floss labeled as “nonstick” or “glides easily,” unless all components are disclosed. Note that PFAS coatings are not usually disclosed.
  • Look for natural fiber dental floss made from biodegradable materials like silk or cotton, as opposed to plastic.
  • Skip flavored flosses if possible.
  • If choosing a flavored floss, look for products that disclose all ingredients and do not simply list “flavor,” “natural flavors,” or “artificial flavor.” Instead look for flavoring from real food ingredients and oils.
  • If you have questions about your favorite floss, contact the company to ask if the floss contains PFAS, plastic, or flavors.