A new study reveals alarming levels of harmful chemicals in rainwater worldwide, raising health concerns.

Rainwater, a vital natural resource that replenishes groundwater and provides drinking water in many regions, has now been found to contain dangerous chemicals in nearly every location across the globe. Researchers from the University of Stockholm have discovered the presence of “forever chemicals” in rainwater, revealing that their concentrations have reached unsafe levels.

These harmful substances, known as per- and poly-fluoroalkyl substances (PFAS), are particularly concerning because they break down extremely slowly, earning them the nickname “forever chemicals.” According to the study, the levels of PFAS in rainwater have surpassed recommended safety guidelines, with serious implications for human health.

What are ‘forever chemicals’?
PFAS are synthetic chemicals commonly used in products such as non-stick cookware, stain-resistant fabrics, and food packaging. These substances are now being found in rainwater, making it unsafe to drink in most parts of the world, including the UK. The study highlights an alarming decline in the acceptable levels of PFAS in drinking water, particularly in the United States, where the safe limit for one of these chemicals, perfluorooctanoic acid (PFOA), has been reduced by an extraordinary 37.5 million times over the past 20 years.

Ian Cousins, the lead author of the study and a professor at Stockholm University, explains that under the current guidelines for PFOA in drinking water, all rainwater would be considered unsafe for consumption.

What impact could this have on our health?
Exposure to PFAS has been linked to several serious health issues, including fertility problems, cancer, and developmental delays in children. Dr. Jane Muncke, managing director of the Food Packaging Foundation in Zurich, has called for stricter regulations on these chemicals. She emphasised the importance of holding the industries that produce and use PFAS accountable for the harm caused, particularly as millions of people face the risks of contaminated drinking water.

While the study sheds light on the growing concern over PFAS contamination, experts stress that immediate action is needed to protect public health and secure clean water sources for future generations.