Oceans Send 'Forever Chemicals' Back To Land

Forever chemicals can actually be reemitted into the atmosphere by ocean waves, a new study has found.

The findings from researchers at the Department of Environmental Science at Stockholm University in Sweden, published in Science Advances, debunked the belief that per- and polyfluoroalkyl substances (PFAS) which are also known as forever chemicals, drain into the oceans where they dilute and become less potent.

Researchers found that the chemicals pas back into the air when large ocean waves crash. And the reemitted levels are greater than other sources.

This creates a "cyclical transport process" for the chemicals "between land and sea," the study reported.

"It was previously widely believed that PFAS in the environment would eventually migrate to the oceans, where it would remain and gradually become diluted into the deep ocean. However, our research has revealed that a portion of the PFAS in ocean water can be re-emitted back into the air," Bo Sha, the main author of the study, told Newsweek.

"The total amount of this re-emission is comparable to other sources of PFAS to air. Nevertheless, the contributions of different sources and emission pathways are still not well understood. Therefore, the extent to which re-emission from the oceans adds to human exposure to these persistent chemicals remains unclear, although it is likely relatively small at present compared to other primary sources."

To reach their findings researchers initiated field experiments across the Atlantic Ocean. They found PFAS concentrations in the atmosphere were over 100,000 times that of sea water concentrations.

Sha said that fellow co-author Jana Johansson worked "intensively for two months on a ship conducting multiple field experiments with our custom-built sea spray simulator" to reach these findings.

"While our results are scientifically impactful, they are disconcerting, creating a lot of interest among scientists, regulators, and the public," Sha said.

PFAS refer to a large family of more than 10,000 chemicals that do not occur naturally. They are generated from various human sources and can be found in certain foods, packaging and many other materials.

They are mainly found in water and the earth. Until now, it was thought that forever chemicals found in the air from evaporated water were not that strong.

They are named as such because they are highly persistent and can last in the environment for thousands of years. Whether we will ever be able to eradicate them from our environment is a question that scientists have not yet been able to answer.

"A significant factor is their "forever" nature. Typically, they do not degrade, or they can transform into other PFAS that remain stable in the environment for extended periods," Sha told Newsweek. "Additionally, they exhibit relatively high mobility, allowing them to disperse easily in the environment."

The main issue with these chemicals is the health risks they pose. They have been linked to very serious conditions such as cancer, fertility issues as well as immune system complications.

This means that any research into how they get into the environment, and how they remain there, is useful to scientists.

"It could affect agricultural land, potentially leading to contamination of grasslands where livestock graze due to PFAS transported by sea spray aerosols," Sha said. "The re-emission of PFAS from the oceans is a consequence of historical and ongoing emissions, and there is little we can do about it other than waiting for PFAS concentrations in the ocean to decrease to negligible levels. PFAS in seawater will be re-emitted from the oceans, transported via sea spray aerosols, and some will deposit onto land. Thus, even if we were to completely halt the use of PFAS, people may still be exposed to low levels of PFAS for an extended period, especially in coastal regions. However, the potential effects of this long-term, low-level exposure on human health are unknown."

Update 04/09/24, 06:04 a.m. ET: This article was updated to include quotes from Bo Sha.

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