In a development that will surprise precisely no one who believes that banning poison reduces poison, levels of some of the most dangerous PFAS compounds have dramatically fallen in Canadian seabird eggs. A new peer-reviewed study says this is what happens when you actually regulate things.
Researchers examined PFAS levels in northern gannet eggs from the St. Lawrence Seaway basin spanning 55 years. The chemicals shot up from the 1960s through their peak in the late 1990s and early 2000s, then fell. The decline coincides with regulatory scrutiny that prompted chemical giant 3M to begin phasing out PFOS, one of its most common and toxic compounds. By 2015, major chemical makers had cut a deal with the U.S. Environmental Protection Agency to phase out PFOS and PFOA, a similarly problematic compound.
Raphael Lavoie, an ecotoxicologist with Environment and Climate Change Canada and co-author of the study, called the findings "good news." "We see this incredible rise to a peak where concentrations seem to be higher than toxicological threshold for those birds, then it really decreases in a nice way," Lavoie said. "The regulations are having a good effect."
PFAS are a class of at least 16,000 chemicals used to make products resist water, stains, and heat. They're called "forever chemicals" because they don't break down naturally, and they're linked to cancer, thyroid disease, kidney problems, and decreased immunity. The eggs came from remote Bonaventure Island, home to North America's largest northern gannet colony. PFOS levels fell from a peak of 100 parts per billion (ppb) to 26 ppb by 2024 - a 74% drop. PFOA levels dropped about 40%, though they've ticked back up in recent years. PFHxS, another common toxic compound, fell from 0.69 to 0.19 ppb, or about 72%.
The paper details how PFAS production surged between 1969 and the mid-1990s, driven by everything from firefighting foams to stain guards. With virtually no regulatory oversight, the chemicals accumulated in the environment, exposing wildlife like the northern gannet. The birds faced high risk as the St. Lawrence received pollution from manufacturing centers around the Great Lakes. As dangers emerged, the U.S., Europe, and Canada ratcheted up pressure with regulations and risk actions. The United Nations targeted PFOS under the 2009 Stockholm Convention, requiring signatory countries to restrict production and use. Militaries and other users of firefighting foam switched to PFAS-free products or stopped using the chemicals in training exercises, significantly reducing water pollution.
But before anyone breaks out the celebratory PFAS-free champagne, there's a catch. Chemical makers moved to newer, smaller PFAS compounds that also pose risks. Those levels have likely grown, though they're harder to measure in bird eggs because they don't accumulate in wildlife as much. And compounds like PFOS linger in the environment and animals' bodies for decades, so the birds and their habitat will remain contaminated for the foreseeable future. The authors wrote that this "emphasizes the importance of maintaining scientific and regulatory vigilance" - which is science-speak for "don't stop now."