A common route for PFAS “forever chemicals” to enter the body is through drinking water.
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A common route for PFAS “forever chemicals” to enter the body is through drinking water.
Invisible and ubiquitous, 'forever chemicals' have been linked to a wide range of serious effects on human health, leading to calls for their ban.
There is strong evidence that at least one of the more than 4,000 man-made chemicals called PFAS causes cancer, but researchers are still trying to fully understand their wide-ranging effects on health. .
Here's what we know so far:
What are PFAS?
Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals first developed in the 1940s to withstand high heat and repel water and oil.
Since then, they have been used in a wide range of household and industrial products, including food packaging, cosmetics, stain-resistant fabrics, nonstick pots and pans, and firefighting foam.
PFAS are called “forever chemicals” because they take so long to break down, but over the years they have leached into soil and groundwater, entering our food chain and drinking water in the process. I did.
These chemicals are now found almost everywhere on Earth, from the top of Mount Everest to the insides of human blood and brains.
the two biggest culprits
The two most studied PFAS compounds have already been banned or restricted in many countries, even though they are still detectable throughout the environment.
Perfluorooctanoic acid (PFOA), once used to make the nonstick Teflon coating on cookware, was classified as “carcinogenic to humans” by the International Agency for Research on Cancer (IARC) in December.
The World Health Organization said there was “sufficient evidence” that PFOA caused cancer in animals during experiments, and “limited evidence” of renal cell and testicular cancer in humans.
Meanwhile, perfluorooctane sulfonic acid (PFOS), once a key ingredient in Scotchgard fabric protectors, has been ruled “possibly carcinogenic to humans.”
IARC said there is limited evidence for animal cancers, but “insufficient evidence for human cancers.”
Other related diseases
More extensive observational studies have shown that exposure to PFAS chemicals is associated with increased incidence of cancer, obesity, thyroid, liver and kidney disease, high cholesterol, low birth weight, infertility, and even decreased response to vaccines. It has been suggested that it is related to.
However, such observational studies cannot prove that chemicals directly cause these health problems.
And the level of risk varies greatly depending on the level of PFAS that people are exposed to. Almost every person on the planet is thought to have at least a small amount of PFAS in their body.
According to IARC, those at highest risk of severe PFAS exposure are those who directly handle the chemicals during product manufacturing.
exposure problem
Exactly what level of PFAS exposure is harmful to health is a matter of debate.
Previously, guidelines in many countries ruled that less than 100 nanograms of PFAS per liter of tap water was sufficient to protect health.
However, the US has proposed lowering the limit for PFOA and PFOS to 4 nanograms per liter, and the EU is considering following suit.
A media investigation last year found 2,100 facilities in Europe and the UK had PFAS levels above 100 nanograms per liter.
An investigation carried out by 16 news organizations found that 300 of the sites had levels rising to 10,000 nanograms or more.
“Chemistry whack-a-mole”
Further complicating research's ability to understand the health effects of PFAS is that new compounds are still being developed.
As manufacturers phase out compounds identified as potentially dangerous, they may simply replace them with other members of the PFAS family that have been less studied, researchers warn. .
Elsie Sunderland, an environmental researcher at Harvard University, calls this process “chemical whack-a-mole.”
call for action
Environmentalists and health experts around the world are increasingly sounding the alarm about eternal chemicals.
On Thursday, French lawmaker Nicolas Thierry will introduce a bill that, if passed, would ban non-essential PFAS in France from 2025.
The European Union is also considering banning PFAS across Europe starting as early as 2026.
What can you do?
For people at home, it is nearly impossible to avoid ingesting trace amounts of PFAS.
But experts recommend reducing contact with nonstick cookware and oil-resistant food packaging, such as fast food wrappers.
Drinking filtered or bottled water and storing leftovers in glass containers rather than plastic may also help.
