Scientists ring alarm bells as spread of forever chemicals reaches aquatic mammals

New research shows that marine mammals living far beneath the ocean’s surface are not shielded from toxic “forever chemicals,” with whales and dolphins exhibiting record-high levels of PFAS contamination.

The results overturn the long-held belief that deep-sea environments protect marine life from human-made per- and polyfluoroalkyl substances (PFAS), as reported in an article for Phys.Org.

Dr. Katharina Peters, a marine ecologist and research leader at the University of Wollongong’s Marine Vertebrate Ecology Lab, contributed to the study led by Te Kunenga ki Pūrehuroa Massey University of New Zealand. The research, titled “No place to hide: Marine habitat does not determine per- and polyfluoroalkyl substances (PFAS) in odontocetes,” challenges assumptions about where PFAS pollution can reach.

“Whales and dolphins are considered indicator species because they reflect their ecosystem. We expected that species feeding mainly in deep water, like sperm whales, would have lower PFAS contamination than coastal species like Hector's dolphins, which are closer to pollution sources. Our analyses show that this is not the case: there really seems to be no place to hide from PFAS,” Dr. Peters warns.

Published in Science of the Total Environment, the study raises concerns about the long-term health of marine wildlife and the enduring environmental footprint of PFAS—synthetic chemicals that number more than 10,000 and do not occur naturally.

PFAS are among the most persistent chemicals ever manufactured; they barely break down in nature and have been detected in the blood and breast milk of humans and animals worldwide. Their ability to disrupt immune, endocrine, and reproductive systems poses risks to both individual animals and entire populations, including cetaceans.

Researchers examined tissues from 127 animals representing 16 species of toothed whales and dolphins found in New Zealand waters—from bottlenose dolphins to deep-diving sperm whales. For eight of these species, including New Zealand’s endemic Hector’s dolphin and three beaked whale species, this marks the first global assessment of PFAS exposure.

Study co-author Dr. Frédérik Saltré, a researcher at the University of Technology Sydney and the Australian Museum, noted that the team found habitat was a weak predictor of PFAS levels.

“Even offshore and deep-diving species are exposed to similar levels of PFAS, highlighting how widespread pollution, compounded by climate-driven stressors, poses a growing threat to marine biodiversity,” he said.

By Nazrin Sadigova