Many of the durable industrial compounds nicknamed ‘forever chemicals’ have become ubiquitous in the environment, from the air to rainwater to the oceans. Forever chemicals called perfluoroalkyl acids (PFAAs) build up in sea spray, and an analysis suggests that oceans could be among the largest source of PFAAs in the atmosphere1.
As air bubbles rise through the oceans, they collect industrial PFAAs that have contaminated the water. When the bubbles burst at the surface, they release the chemicals into the atmosphere.
Bo Sha at Stockholm University and his colleagues sampled seawater during a research cruise in the Atlantic Ocean. They pumped a jet of the water into a shipboard chamber, creating bubbles that released sea spray as they burst inside the chamber.
The authors analysed the simulated sea spray and found that its PFAA levels often reached concentrations that were more than 100,000 times greater than those in the seawater itself. The team estimates that emissions of two common forever chemicals, perfluorooctanoic acid and perfluorooctane sulfonic acid, from the oceans equal or exceed the total emissions from known industrial sources.
