A new study has found that compounds introduced in the early 1990s to replace ozone-depleting chemicals can lead to the accumulation of other nasty chemicals that persist in the environment indefinitely.
The chemicals began to emerge in the environment after the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer started the phase-out of ozone-depleting chemicals, chlorofluorocarbons (CFCs), such as those used in older air conditioners. The protocol managed to save the ozone layer and has been praised as the most successful global environmental action ever taken. However, as this new research shows, it’s had some unintended consequences.
The chemicals in question are short-chain perfluoroalkyl carboxylic acids (or scPFCAs), which are a class of human-made chemicals used in electronic applications, industrial processing, construction, and air-conditioning. They belong to a wider group of polyfluoroalkyl substances, known as PFASs or “forever chemicals” due to their persistence, that have been linked to a number of health problems, including cancer.
Reported in the journal Geophysical Research Letters, researchers from York University and Environment and Climate Change Canada have recently discovered the growing presence of scPFCAs in our ecosystems by looking at ice core samples taken from the Arctic.
"The ice cores are useful because they act as our time capsule and provide a record of contamination. Thus, it's one of the only ways we can understand these trends," Cora Young, an assistant professor and environmental chemist at York University, told IFLScience. "This process will happen everywhere, so we expect the contamination is global."
The study did not look to understand how the presence of scPFCAs in Arctic ice might affect the health of humans or the environment, so it’s unclear how concerning these findings are. Nevertheless, the paper says the chemicals “are characterized by resistance to environmental degradation and potential adverse impacts on human and environmental health.” Since they don’t break down in the environment, the chemicals work their way into water supplies and food, meaning they inevitably end up in human tissues where they can accumulate.
"The concern for me is that little is known about the potential human and ecological harms of these compounds," Young explained. "We know that they accumulate in plants, including those that humans consume. We also know that they are extremely persistent in the environment. Thus, if we discover down the road that there are toxic effects, we will already be faced with their global environmental presence."