A new European study has found that 90% of so-called eco-friendly paper straws contain “forever chemicals,” compounds that don’t – or barely – break down and can accumulate in our bodies, leading to health problems. The findings are consistent with results from a recent US study.

“Forever chemicals” is the colloquial name given to a class of more than 12,000 chemicals, more formally known as poly- and perfluoroalkyl substances (PFAS), that barely break down in the environment or in our bodies. Hence, the “forever” part.

Humans are mainly exposed to PFAS through food and drinking water. In addition, many food packaging materials and plastic bags can also contain PFAS, which can be transferred to the food we eat. With a 2021 US study finding that PFAS was present in plant-based drinking straws, researchers from the University of Antwerp in Belgium analyzed straws made of various materials to see if the same was true in Europe.

The researchers tested 39 different brands of straws made from paper, glass, bamboo, stainless steel, and plastic, and analyzed them for 29 different PFAS compounds.

The majority of brands tested (69%) contained PFAS, with 18 different PFAS detected in total. Paper straws were most likely to contain PFAS, with the chemicals detected in 90% of the brands tested, albeit in highly variable concentrations. Perfluorooctanoic acid (PFOA), a compound linked to high cholesterol, a reduced immune response, thyroid disease and increased kidney and testicular cancer, was most frequently detected. PFOA has been banned globally since 2020. Also detected were trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFMS), ultra-short-chain PFAS that are highly water-soluble and so might leach out of straws into drinks.

Bamboo straws fared only slightly better than paper ones, with PFAS found in 80% of brands tested. The chemicals were found in 75% of plastic straws and 40% of glass brands. PFAS were not detected in any of the steel straws tested.

“Straws made from plant-based materials, such as paper and bamboo, are often advertised as being more sustainable and eco-friendly than those made from plastic,” said Thimo Groffen, the study’s corresponding author. “However, the presence of PFAS in these straws means that’s not necessarily true.”

The PFAS concentrations were low and, the researchers say, pose a small risk to human health. However, the problem with PFAS is that they’re bioaccumulative, meaning they can build up over time because they’re absorbed but not excreted.

“Small amounts of PFAS, while not harmful in themselves, can add to the chemical load already present in the body,” said Groffen.

The researchers say that while the study did not determine whether PFAS were added to the straws or were the result of contamination – for example, from the soil in which the plant-based materials are grown – the presence of the chemicals in almost every brand of paper straw means it’s likely that, in some cases, PFAS were used as a water-repellent coating. The study also did not examine whether PFAS leached out of the straws into the liquid they were sitting in.

To be safe, the researchers suggest people start using stainless steel straws, or ditch straws altogether.

“The presence of PFAS in paper and bamboo straws shows they are not necessarily biodegradable,” Groffen said. “We did not detect any PFAS in stainless steel straws, so I would advise consumers to use this type of straw – or just avoid using straws at all.”

The study was published in the journal Food Additives and Contaminants.

Source: University of Antwerp via Scimex