Reflections on rainwater

One of my best memories growing up in Switzerland is drinking from flowing mountain streams while hiking with my family. It tasted fresh and delicious. Hopefully, such experiences won’t become a thing of the past because of new persistent fluorinated pollutants.

The global pollution crisis involving per- and polyfluoroalkyl substances (PFAS) has ballooned since first becoming public about 20 years ago. New research on the atmospheric transport of PFAS has concluded that it has exceeded a ‘planetary boundary’. Conceived of over a decade ago, planetary boundaries describe a ‘safe operating space’ that will cause large scale or irreversible environmental change if breached. The nine originally identified include climate, biodiversity and ocean acidification.