One in three dental floss contain the fluorinated substance PTFE.
A new study by the Danish Consumer Council THINK Chemicals shows that 20 out of 59 types of dental floss contain the unwanted fluorinated substance.
PTFE is also known as Teflon and is one of many per- and polyfluoroalkyl substances, or PFAS.
In dental floss, PTFE is often marketed with “making the floss slide more easily between the teeth and less likely to shred”.
It is not only in Denmark that fluorinated substances have been found in dental floss. An American test finds similar findings in every third dental floss.
Why fluorinated substances are a problem
PFAS, or fluorinated substances, accumulate in nature and in the body. They are suspected of weakening the immune system, increasing cholesterol levels in the blood, and causing increased risks of liver damage, cancer, hormonal disruptions, miscarriage and lung damage.
Dental floss with PTFE is not a problem in itself. However you are exposed to fluorinated substances from many sources. Through food, indoor air, outdoor clothing and care products among other things.
If you choose a dental floss and other consumer products without fluorinated substances, you limit the spread of the substances in the environment and your total exposure to the substances. Multiple exposure is also known as the cocktail effect.
Dental floss with PTFE
Here are examples of dental floss with the fluorinated substance PTFE from our test. All products are purchased in Danish stores or online.
We have not tested dental floss for PTFE in a laboratory.
Dental floss without PTFE
Here are examples of dental floss that, according to the companies, do not contain PTFE.
How to avoid PTFE in your dental floss
- Look for the fluorinated substance PTFE on the packaging. Be aware that you can find dental floss that contain PTFE, where the content is not labelled on the packaging.
- Ask the companies or retailers if you want to be completely sure that your dental floss is without PTFE.
Dental floss: Half of them are without information about PTFE
In our test, 10 out of 20 dental floss products contain PTFE without declaring it on the packaging.
The companies confirm the PTFE content after we contacted them.
Some also provide information about the content of PTFE on their website.
For the other half of the products you can find information about PTFE on the packaging of you dental floss.
However, there is no guarantee. Companies are not obliged to disclose the ingredients on the packaging.
Dental floss with fluoride is not the same thing
Dental floss can also contain the same kind of fluoride that you will find in toothpaste. It is called inorganic fluoride and helps prevent caries.
Fluoride is not the same as the fluorinated substance PTFE. You can safely buy dental floss with fluoride.
Eco-labelled dental floss does not exist
Products with the Nordic Swan Ecolabel are not allowed to contain fluorinated substances. Unfortunately, you cannot buy dental floss with the Nordic Swan Ecolabel or the EU Ecolabel.
“The criteria for hygiene products focus on products that need to absorb liquid. Therefore, the requirements of the criteria are based on the fact that the materials used must be able to absorb liquid”, says Head of Criteria in Ecolabelling in Denmark, Heidi Belinda Bugge.
PTFE may be the source of other fluorinated substances
For the most part PTFE or Teflon is a stable fluorinated substance when used as coating on non-stick pots and pans. It is typically only released from frying pans at a very high temperature.
Dental floss manufacturers inform the Danish Consumer Council THINK Chemicals that the PTFE they use is also clean, stable and thus safe to use.
On the other hand, a study from the Danish Environmental Protection Agency shows that cosmetic products with PTFE may contain a number of other problematic fluorinated substances, which are not declared on the products.
The occurrence of the undeclared fluorinated substances may be due to contamination from PTFE or that PTFE can be broken down into other fluorinated substances.
Based on this we do not know for certain, which fluorinated substances can be found in the products.
Study finds PTFE in the blood
The extent to which people are exposed to the fluorinated substance PTFE in dental floss is difficult to answer.
An American study indicates that dental floss made from PTFE can be a source of fluorinated substances in the blood.
The study compared fluorinated substances in the blood of 178 women with their consumption patterns such as eating habits and the use of dental floss.
The result shows a correlation between flossing with PTFE and higher levels of fluorinated substances in their blood.
The study also underlines that more data is needed to establish the connection.
Companies want to phase out PTFE in dental floss
Several of the companies in the study reply that they expect to phase out or are in the process of phasing out the sale of dental floss with PTFE.
Some companies also emphasize that they clearly state the content of PTFE on the packaging, so that consumers can choose whether they prefer dental floss with or without PTFE.
What the companies say
“There is only one dental floss in our range that contains PTFE. It is GUM Easy Floss, where it is stated on the package so the consumer can make an informed decision.
We have now decided to stop selling this dental floss. All our other dental flosses are PTFE-free”.
Mundfrisk, retailer for Active Oral Care, Pierrot and UltraClean.
“We state the content of fluoride and not least PTFE in the dental floss, as many consumers deselects these products. However, other people still prefer the floss with PTFE, as they otherwise will not be able to use dental floss.
In all cases, we want to be able to provide dental care to everyone, and we believe that our customers should be able to make their own choices – we should not make the choices for them. Therefore, we will not discontinue products unless these deviate from Danish legislation or are of poor quality. On the other hand, we prioritize correct product texts, just as there are ingredient lists on all relevant products. Furthermore, you can always get in touch with us by chat, email or phone if there should be any doubt.
And wonderful that THINK processes these things. This makes it easier for the consumer, but also for us, to orient oneself. We support it”.
“Colgate dental floss is safe for the consumer to use. Colgate-Palmolive uses polytetrafluoroethylene (PTFE) fibers in our floss products, so the floss slides more easily between the teeth, which can be beneficial for consumers who find it difficult to clean their teeth.
The fluorinated substances in PTFE are chemically bound and are not released unless heated to 315-500 °C, which is why the products – on equal terms with products without PTFE – are safe for consumers to use. Our floss does not contain any of the following ingredients: Perfluoroalkoxy alkanes (PFA) or perfluorohexane sulfonic acid (PFHxS).
Although PTFE is a safe ingredient in our dental floss, we are aware of the concerns about its use, and we are therefore in the process of reformulating our dental floss and phasing out the use of PTFE. Both of Colgate’s floss products will transition to a PTFE-free thread, which you can find in the stores starting November 2022”.
“We are working on an alternative thread for one of our products that contains PTFE”.
“PTFE in the floss provides a solid thin tapeshaped thread with low friction, which allows it to floss in narrow spaces. Many users want these properties, which is why it is a common material in dental floss. It is stated on our website if a product contains PTFE. We do not believe that using our PTFE dental floss poses any health hazard. However, we do understand the concern, and are actively working to find a replacement, which can meet our requirements for quality and function. Unfortunately, we just haven’t succeeded yet”.
“We offer various options to our Oral-B consumers to meet their needs, including flossing with PTFE. PTFE is similar to Gore-Tex in textile. The PTFE material slides more easily between teeth and is less prone to unraveling compared to standard dental floss. PTFE is a very stable fluoropolymer that also contains fluoride, but neither fluoride nor PTFE is bioavailable or bioaccumulable – it cannot cross cell membranes. Our dental floss undergoes various safety tests. The safety of the consumers who use our products is our top priority and we continue to support the safety of all our products”.
“If you want to avoid perfluorinated substances, you should avoid those variants with PTFE and instead choose one of our variants without perfluorinated substances: TANDEX Round Dental Floss or TANDEX Flat Floss”.
“Regarding the study of dental flossing containing PTFE on the Danish market, we have decided to phase out our variant containing PTFE and focus on our variants without PTFE. Even though there is no evidence, that PTFE is harmful to humans, before it is exposed to temperatures above 260 degrees”.