A new international study has revealed that whales and dolphins living far from coasts and deep below the ocean’s surface are not protected from toxic “forever chemicals.”
Instead, these marine mammals are showing unprecedented levels of PFAS contamination, raising major concerns about ocean health.
The research, published in Science of the Total Environment, challenges the long-held belief that deep-sea species are less exposed to human-made pollutants.
PFAS—short for per- and polyfluoroalkyl substances—are a group of chemicals used in everyday products such as non-stick cookware, waterproof clothing, firefighting foam, and food packaging.
They are known as “forever chemicals” because they do not break down easily and can remain in the environment for decades. PFAS accumulate as they move through the food chain and have been linked to immune, hormonal and reproductive problems in both humans and animals.
Dr. Katharina Peters, a marine ecologist from the University of Wollongong’s Marine Vertebrate Ecology Lab, worked on the study, which was led by researchers at Massey University in New Zealand.
She says the results were unexpected and alarming. Scientists initially thought that deep-diving species like sperm whales, which feed far offshore, would have lower levels of PFAS compared to species that live close to polluted coastlines. But the data told a very different story.
“Our analyses show that habitat doesn’t matter—PFAS are everywhere,” Dr. Peters said. “Whales and dolphins are indicator species, meaning their health reflects the health of their environment. The fact that even deep-water species have high contamination levels shows just how widespread these chemicals have become.”
The team analyzed tissues from 127 dolphins and whales across 16 different species found in New Zealand waters.
The sample included coastal animals such as bottlenose dolphins and offshore or deep-diving species such as beaked whales and sperm whales. For eight of these species—including Hector’s dolphin, which is unique to New Zealand—this was the first time PFAS levels had ever been measured.
The researchers also examined how PFAS exposure varied by species, age, sex and feeding location. Study co-author Dr. Frédérik Saltré, from the University of Technology Sydney and the Australian Museum, says the results showed a clear pattern: habitat was not a reliable predictor of contamination.
“Even species that live far offshore or dive to great depths are exposed to the same levels of PFAS as those near shore,” Dr. Saltré said. “This shows how pollution spreads across oceans, and when combined with climate change, it creates serious risks for marine biodiversity.”
The study, involving researchers from Australia and New Zealand, is the first comprehensive assessment of PFAS across such a wide range of marine mammal species living in different habitats at the same time.
The findings underscore the lasting impact of human-made chemicals and highlight the urgent need for stronger global action to protect marine life from invisible but dangerous pollutants.
Source: University of Wollongong.
