Researchers from the Marine Mammal Foundation and the University of Melbourne have documented alarmingly high levels of PFAS, a class of persistent chemicals often labeled as forever chemicals, in endangered Australian bottlenose dolphins. The findings highlight a pressing environmental health concern for marine life along the southern coast of Australia, particularly in habitats near Port Phillip Bay.
Per- and polyfluoroalkyl substances, collectively known as PFAS, are synthetic compounds used for their resistance to heat, water, and oil. They appear in an array of everyday products, from cookware and food packaging to textiles and firefighting foams. With more than ten thousand distinct PFAS identified to date, these chemicals are notably stable and capable of accumulating in soil, water, and biological tissues, leading many scientists to describe them as virtually unbreakable in natural environments.
In a field-based assessment, researchers collected tissue samples from 38 dolphins of multiple species that had stranded along the Victorian coastline. The most elevated PFAS concentrations were found in dolphins inhabiting the Port Phillip Bay region, underscoring a potential hotspot of exposure.
Across the sampled individuals, average PFAS burdens approached thresholds known to threaten hepatic and related organ function in marine mammals. In one notable case, a juvenile bottlenose dolphin carried an exceptionally high PFAS load in its liver, reaching nearly twenty thousand nanograms per gram of tissue, a record for this species worldwide. This level of contamination coincides with concerns about long-term health effects, including liver stress, immune modulation, and disruptions to endocrine signaling.
Australian bottlenose dolphins were recognized as a distinct population in 2011 and are a geographically restricted group found only along Australian shores. Current estimates place their total population at a few hundred individuals, emphasizing their vulnerability to environmental stressors and habitat changes.
Analyses point to several primary pathways introducing PFAS into coastal waters. Industrial wastewater discharges, municipal and industrial effluents, landfill leachates, and the use of firefighting foams in areas adjacent to waterways rank among the most significant sources. The detected contamination patterns also reveal the presence of additional, previously unrecognized PFAS compounds. These newer substances appear to bioaccumulate up the food chain, ultimately reaching apex predators such as dolphins.
What these results imply goes beyond dolphins. PFAS can persist in ecosystems for extended periods, and their transfer through aquatic food webs raises concerns for other wildlife and human communities relying on similar coastal habitats. The study underscores the need for comprehensive monitoring, stricter wastewater management, and targeted remediation efforts to reduce ongoing exposure.
In a broader context, researchers have explored avenues to repurpose harmful PFAS by transforming them into useful raw materials, though the practical implementation of such recycling methods remains a topic of ongoing investigation and debate among scientists and policymakers.