Toxic ‘forever chemicals' have infiltrated Antarctic waters: Study

The Hill

15-07-2025

The frigid waters that surround Antarctica may be inhospitable to human inhabitance, but they are churning with the manmade relics of toxic chemical production, a new study has found.
Certain types of 'forever chemicals' are present in ocean areas west of the Antarctic Peninsula at levels comparable to those in the North Atlantic, according to the study, published in Communications Earth & Environment.
These findings, the study authors stated, underscore the importance of considering persistence when weighing environmental risk, while shedding light 'on the impact of the larger pool of per- and polyfluoroalkyl substances,' also known as PFAS.
There are about 15,000 types of these so-called 'forever chemicals,' many of which are linked to cancers and other serious illnesses. Known for their ability to linger in the environment, PFAS are found in certain firefighting foams and in a variety of household products, such as waterproof apparel, nonstick pans and cosmetics.
Although previous studies have suggested only a limited presence of PFAS in the Southern Ocean, the authors — from Spain's Institute of Environmental Assessment and Water Research and the University of Barcelona — were able to challenge this assumption.
The prevailing notion, they explained, reasoned that the 'circumpolar current' that flows clockwise around Antarctic prevented the transport of PFAS southwards.
Yet at the same time, the researchers recognized that oceans have become 'a major reservoir' of a PFAS subgroup called perfluoroalkyl acids (PFAAs) — and that certain precursors of PFAAs had been identified in the Southern Ocean's atmosphere.
'PFAAs are widely distributed in tropical and subtropical oceans and are extremely persistent in the environment,' the authors stated.
Among the two most notorious types of PFAAs around the world are PFOA and PFOS — carcinogens that have largely been phased out of production but that remain in soil and water resources due to their longevity.
To determine whether these persistent — and often toxic — types of PFAS had in fact infiltrated the Southern Ocean, the scientists conducted on-site water sampling in the area, accompanied by analytical procedures.
In doing so, they identified PFAA concentrations in seawater at Antarctic latitudes of 71 degrees south comparable with those of 37 degrees north — in regions with known PFAS sources across Europe, the Mediterranean, Central Asia and the United States.
Given the circumpolar current's likely role as 'a barrier for the north-south transport of PFAAs by oceanic currents,' the researchers focused on a possible mechanism called 'wet deposition,' when aerosolized pollutants fall from the atmosphere with rain or snow.
The scientists ultimately determined that PFAA compounds are transported via ocean currents from the southern subtropical Atlantic to the sub-Antarctic — the zone immediately north of the Antarctic region.
From there, what likely occurs is a phenomenon known as 'sea-spray mediated grasshopping,' in which PFAA-laden sea spray forms in the atmosphere and then deposits in the Southern Ocean, per the study.
The Southern Ocean, the authors explained, is known for its high wind speeds, and the region in general endures 'incursions' of wet air masses from the north.
Once the compounds have made it into the Antarctic region and have crossed a maritime barrier called 'the Antarctic divergence,' they are generally there to stay, the study found.
This polar PFAS pileup, the authors warned, raises concerns about potential risks posed to the Antarctic ecosystem. They therefore stressed a need for further research into the prevalence of such 'persistent contaminants of emerging concern' across the region.
'This unexpected accumulation evidences the global risk posed by persistent chemicals,' the authors added.