Waterproof only with poison?
For a rain jacket to be truly waterproof, it needs a membrane. This is a very thin plastic layer that keeps rainwater out but allows sweat to escape to the outside. Often, rain jackets for mountaineering and ski touring use membranes made of the plastic polytetrafluoroethylene (PTFE). Unfortunately, PTFE is anything but sustainable and may even be dangerous.
The Problem: disposal.
PTFE is not directly dangerous to humans. This is because it is one of the most stable plastics in the world and does not react with the human body. The problem is, every jacket with a PTFE membrane will eventually reach the end of its life. Then it has to be disposed of, because recycling a PTFE jacket is technically possible, but is not practiced for economic reasons . This means that an old jacket with a PTFE membrane either ends up in a landfill and - because it cannot be degraded by nature - remains there for all eternity. Or it is incinerated.
When an old jacket with a PTFE membrane is burned, so-called hydrofluoric acid is produced . Hydrofluoric acid is highly toxic and causes a kind of skin burn when it comes into contact with the skin. Already at burns of only 2.5% of the human body surface hydrofluoric acid leads to death . But the respiratory tract can also be severely damaged: the burning of PTFE produces aerosols that contain hydrofluoric acid and can cause severe corrosions in the human respiratory tract - this can also lead to death .
First the good news: the formation of hydrofluoric acid during the combustion of a jacket with a PTFE membrane is not a problem in a Swiss waste incineration plant. This is because these have very efficient waste gas purification systems that can eliminate hydrofluoric acid very effectively .
The bad news is that many jackets with PTFE membranes end up in developing countries via used clothing collections and clothing donations . There, people may actually come to harm if old jackets with PTFE membranes are improperly incinerated - for example, in landfills by smoldering fires or on open fires. However, there are hardly any scientific studies that really reveal the exact paths and fates of old clothing. However, it is scientifically confirmed that around 80% of the clothing produced worldwide ends up in landfills or is incinerated in some way .
PTFE and CO2
Unfortunately, that's not all: PTFE emits more than twice as much CO2 in production as comparable membranes made of polyester and even almost three times as much as membranes made of polyurethane . Since the climate crisis is one of the biggest threats in the future, we take this very seriously.
ROTAUF and PTFE
After you made it this far, you probably guessed it: since the first functional jacket in 2012, ROTAUF has completely abandoned the use of PTFE membranes. It's too risky to use a material that, if disposed of incorrectly, could in the worst case directly cause serious harm to a human being. Since 2015, ROTAUF has been working closely with the German company Sympatex and uses their membrane for all waterproof and breathable products. Sympatex has been a leader in the development and production of sustainable membranes made of polyester for almost 30 years. These membranes are not dangerous for humans or nature, neither during production nor during disposal, and they are also much more climate-friendly than PTFE.
 https://www.gore-tex.de/service/h%C3%A4ufige-fragen, last visited Feb. 28, 2021.
 Aleksandrov, Krasimir et al: Waste incineration of polytetrafluoroethylene (PTFE) to evaluatepotential formation of per- and poly-fluorinated alkyl substances(PFAS) influe gas. In: Chemosphere, 226, 2019, pp. 898-906. Note: an author of this study is employed by W.L. Gore & Associates, the owner of the Gore-Tex brand.
 Bertolini, John: Hydrofluoric acid: A review of toxicity. In: The Journal of Emergency Medicine, 10, 1992, pp. 163-168.
 https://gestis.dguv.de/data?name=520038, Hazardous Substances Information System of the German Social Accident Insurance, last visited 28.2.2021.
 Schenk, K. et al: : MWIP residues in Switzerland. The raw material with added value. Federal Office for the Environment Bern, 2010.
 http://www.approved-mag.de/slider-auf-startseite/die-spenden-aktion-von-the-north-face/667/, Approved Mag, A. Lewinsky Verlag, last visited on 03.03.2021.
 https://www.dw.com/de/der-altkleider-wahnsinn-mit-spenden-schlechtes-tun/a-46450796, Deutsche Welle, Foreign Broadcasting of the Federal Republic of Germany, last visited 03.03.2021.
 Koszewska, Małgorzata: Circular Economy - Challenges for the Textile and Clothing Industry. In: AUTEX Research Journal, 18, 2018, pp. 337-347.
 https://portal.higg.org/, Higg Materials Sustainability Index, Sustainable Apparel Coalition, last visited 09.03.2021.