The highlight, among a series of other values of interest, is that rainwater, despite not being the main option for drinking, it is no longer drinkable anywhere in the world due to the presence of PFAS. Not even in regions as remote as Antarctica or Tibet.
Goodbye drinking rainwater
The results of the research, published in Environmental Science & Technology, show the presence of perfluoroalkylated and polyfluoroalkylated substances, which we will simply call PFAS for its acronym in English.
According to the samples, the presence of perfluorooctanoic acid (PFOA)also known as C8 and perfluorooctanoate in rainwater exceeds safe drinking ranges. “Under the latest US guidelines for PFOA in drinking water, rainwater everywhere would be considered unsafe to drink. Although we don’t often drink rainwater in the industrial world, many people around the world expect it to be safe to drink and to supply many of our drinking water sources.” said Ian Cousins, lead author of the study and a professor in the Department of Environmental Sciences at Stockholm University.
The team from this university has carried out laboratory and field work on the atmospheric presence and transport of PFAS during the last decade. With the analyzed data, they have noticed that the harmful levels of some PFAS in the atmosphere are not declining notably despite the fact that the main manufacturer, 3M, phased them out two decades ago.
It’s known that PFAS are highly persistent, but its continued presence in the atmosphere is also due to its natural properties and processes that continually recycle PFAS back into the atmosphere from the surface environment. An important natural cycle process for PFAS is transport from seawater to marine air by marine aerosols, which is another active research area for the Stockholm University team.
PFAS are harmful to health
PFAS is a collective name for highly fluorinated substances that have a similar chemical structure. All PFAS are either extremely persistent in the environment or break down into extremely persistent PFAS, earning them the nickname “eternal chemicals”.

If humans, or animals, ingest PFAS (by eating food or drinking water that contains PFAS), PFAS are absorbed and can accumulate in the body. PFAS remain in the human body for a long time. Therefore, as people are exposed to PFAS from different sources over time, the level of PFAS in the body can increase to the point where they experience detrimental health effects.
PFAS have been linked to a wide range of serious health damageincluding cancer, learning and behavior problems in children, infertility and pregnancy complications, increased cholesterol, and immune system problems.
Dr. Jane Muncke, CEO of the Food Packaging Forum Foundation in Zurich, Switzerland, and who was not involved in the research, notes: “It cannot be that a few benefit economically while polluting the drinking water of millions of people and causing serious health problems. The large amounts it will cost to reduce PFAS in drinking water to levels that are safe according to current scientific knowledge must be paid for by the industry that produces and uses these toxic chemicals. The time to act is now”.