Should you comply with the science information, you will most likely see analysis popping out each week about PFAS – the place they’re discovered, the place they arrive from, and their affect on well being and the setting. However what are these chemical compounds actually and why is there a lot curiosity in them?
PFAS stands for “per- and polyfluorinated alkyl substances” – however except you are a chemist, that most likely will not do a lot.
“Fluorinated” signifies that PFAS molecules include the ingredient fluorine, and “per or poly” signifies that there are a lot of fluorine atoms. In natural chemistry, “alkyl” refers to a chemical group containing at the very least one carbon atom bonded to 2 or three hydrogens.
“PFAS is just like naturally occurring hydrocarbon chemical compounds, however the halogen ingredient fluorine replaces most or all the hydrogen atoms within the construction,” explains Rolf Halden, professor at Arizona State College’s Heart for Biodesign Environmental Well being Engineering. WE.
PFAS are additionally totally artificial – that means they don’t seem to be discovered within the pure world. On the whole, fluorinated chemical compounds are very uncommon in nature.
This high quality has traditionally been seen as a bonus, says Mark Jones, a retired industrial chemist and trade guide previously with the Dow Chemical Firm.
“Forty years in the past, after I first encountered fluoridation in an natural chemistry class, it was spoken of for example of one thing that was purely artificial…so they’d be secure as a result of they would not be interacting with biology,” he recollects.
Since they had been first synthesized within the Nineteen Forties, new PFASs have been invented over time and now quantity within the hundreds. Perfluorooctanoic acid (PFOA) – utilized in carpets and fabric, textiles and clothes, and firefighting foam – and perfluorooctane sulfonate (PFOS) are two older PFASs which can be broadly used and studied.
Nonetheless, there may be surprisingly little consensus on precisely which chemical compounds ought to be categorized as PFAS. A 2022 examine from Boston College highlighted how totally different U.S. regulatory companies and nonprofits outline PFAS in numerous methods. The examine discovered that some fluorine-containing prescribed drugs are thought of PFAS in some definitions however not in others.
“The factor about defining it’s actually sneaky,” says Jones, who not too long ago wrote about this for the American Chemical Society. Business Matters e-newsletter. It defines the stress between defining PFAS as a listing of particular chemical compounds or extra broadly primarily based on the presence of sure chemical properties.
“It is a enjoyable recreation to play together with your chemistry buddies: ‘Is 1,4-difluorobutane a PFAS or not?’” Jones jokes. “Most individuals do not get it proper.”
What will we use PFAS for?
PFAS are versatile chemical compounds. They’re present in shopper merchandise corresponding to meals packaging, cookware, clothes, furnishings, tenting gear, dental floss and stain removers.
A lot of this is because of its helpful chemical properties. For instance, PFAS’s warmth resistance is helpful for coating non-stick pots and pans. PFAS may make textiles and different merchandise water and stain resistant.