Firehose

PFAS


Some facts about forever chemicals

The chemicals per- and polyfluoroalkyl substances (or PFAS) are commonly known as forever chemicals because they don’t break down in the environment.

 

PFAS comes in a very large subgroup (about 6.000) of chemicals - best known are PFOS, PFOA, PFNA og PFHxS.  What they have in common in this chemical family is that they are fused with virtually indestructible bonds of carbon and fluorine atoms (hence the nickname “forever chemicals". 

 

3M and DuPont (who invented the chemicals some 60-70 years ago) knew decades ago that hundreds of PFAS break down to either PFOA or PFOS in people, animals and the environment. Newest research show that these chemicals may be some of the most harmful to us - even in ultra small quantities. 

Chemical companies have declared that many PFAS formulas are trade secrets, making it difficult for scientists to identify the compounds and determine if they are harmful. So the whole thing is extremely complex.

 

The forever chemicals are now everywhere, in all of us and getting rid of it is an illusion. The chemicals end up in lakes, rivers and wells after flushing through sewage treatment plants and spreading from factory chimneys. The chemicals also leach out of products such as carpets, clothing, cookware, cosmetics, dental floss, fast-food wrappers, firefighting foam, food packaging, microwave popcorn bags, paper plates, pizza boxes, rain jackets and ski wax. 

Latest research find that tiny concentrations can trigger testicular and kidney cancer, birth defects, liver damage, impaired fertility, immune system disorders, high cholesterol and obesity. Links to other diseases are suspected, in part because the chemicals disrupt albumin, a protein that carries hormones and vitamins through the bloodstream. The cocktail effects with other chemicals makes the matter impossible to analyse and understand for meny, meny years to come.

 

Forever chemicals in water and food

 

Forever chemicals is everywhere. If the cow eats grass in a field close to a fire fighting school - the steak will have forever chemicals (actual case from Denmark 2021). 
 

How to remove forever chemicals in drinking water

There is no clear answer to this question - since there are numerous variations of the chemicals and testing these up against new and existing water treatment technologies is ongoing. But there are some indications for large scale technologies.

For home use we can see that RO can reduce PFAS with up to 90%. Read more here

Distillation (which is WaterStillar's "technology"): Yes or to some extent. Our reasoning is like this: If the boiling point of a contaminant is over the boiling point of water it will stay behind and not move with the water to the distillate. To be absolutely certain, WaterStillar has set a security limit of 140C as a contaminants boiling point - in this way WaterStillar can be certain that distillation will leave contaminants behind.

But not only a high boiling point is in play here. The vapour pressure also needs to be low to ensure that no contaminant will find its way to the distillate. WaterStillar has set a security vapour pressure to be < 0.053 Pa.

Looking at the many different forever chemicals, we can see that the boiling point is generally higher than 140C. Which means a elimination. But at the same time the vapour pressure may be >0.053 Pa - which means only testing will show if any of the chemicals will be transferred. Most likely not, but data isn't available at this time and that is why we do not give WaterStillar a green in our contaminant database.

*****************

A quick overview - read more here in this EPA paper.

One step deeper - see the detailed properties of forever chemicals here (ITRC).