Alligators living in PFAS polluted waters may have weakened immune systems
Alligators are a species that date back more than 150 million years and bore witness to the extinction of the dinosaurs. However, a new study suggests that these apex predators are under threat from a family of synthetic persistent chemicals called PFAS.
Researchers from North Carolina State University looked at populations of alligators living around The Cape Fear River Basin in Central and Coastal Carolina, which comprises 9,300 square miles of waterways and serves ~5.2 million people. There is also a Chemours plant within the basin which manufactures some PFAS chemicals – previous studies have found elevated levels of some PFAS in fish, birds and humans living in proximity to the waterway.
The researchers tested 49 alligators and compared the levels of PFAS in their bodies against a control group of 26 alligators. They found that alligators living in Cape Fear had elevated levels of 14 PFAS chemicals and were contaminated with an average of 10 different PFAS, compared to 5 different PFAS in the control group.
PFAS, also known as ‘forever chemicals’, are a family of chemicals that are resistant to breaking down and persist in the environment for decades. They are added to a range of consumer products due to their ability to repel grease and water. Links between PFAS exposure and health issues, including the promotion of certain cancers and immune system dysfunction, have been documented in several studies.
Alligators with elevated PFAS levels were observed to have a number of skin lesions as well as unhealed and infected wounds. Scott Belcher, co-author of the study, said “Alligators rarely suffer from infections. They do get wounds, but they normally heal quickly”.
A genetic analysis of the alligators revealed significantly elevated levels of genes associated with stimulating immune response, finding they were than in alligators living in non-polluted areas. In humans an increased level of this gene is an indicator of auto-immune diseases, such as lupus.
As a potentially predictive sentinel species, adverse effects observed in alligators may be indicative of health issues posed by PFAS pollution in humans.
Belcher concludes “seeing these associations between PFAS exposure and disrupted immune function in the Cape Fear River alligators supports connections between adverse human and animal health effects and PFAS exposure.”
CHEM Trust and partners have recently launched their ‘Ban PFAS manifesto’ which urges the European Commission and EU Member States to ban PFAS in consumer products by 2025 and across all uses by 2030.