This includes makeup, dental floss and menstrual products. They are found in non-stick pans and food wrappers. The same with jackets and firefighting equipment, as well as pesticides and artificial turf in sports fields.
They are PFAS: a class of man-made chemicals called per- and polyfluoroalkyl substances. They are also called “forever chemicals” because the bonds in their chemical compounds are so strong that they do not break for hundreds to thousands of years, if at all.
It’s also in our water.
A new study of more than 45,000 water samples worldwide found that about 31 percent of groundwater samples tested that were not near any obvious source of contamination had levels of PFAS considered harmful to human health by the Environmental Protection Agency .
About 16 percent of the surface water samples tested, which were also not near any known sources, had similarly dangerous levels of PFAS.
That finding “sets off alarm bells,” said Denis O’Carroll, a professor of civil and environmental engineering at the University of New South Wales and one of the authors of the study, which was published Monday in Nature Geoscience. “Not just for PFAS, but for all the other chemicals we release into the environment. We don’t necessarily know their long-term effects on us or the ecosystem.”
High levels of exposure to certain PFAS chemicals have been linked to higher cholesterol, liver and immune system damage, hypertension and preeclampsia during pregnancy, as well as kidney and testicular cancer.
The EPA has proposed new strict drinking water limits for six types of PFAS and could announce its final rule as early as this week.
For their research, Dr. O’Carroll and colleagues compiled nearly 300 published studies on PFAS in the environment. Together, these studies included 12,000 samples from surface water — streams, rivers, lakes and ponds — and 33,900 samples from groundwater wells, collected over the past 20 years. These samples do not cover the entire planet: they are concentrated in places with more environmental researchers, such as the United States, Canada, Europe, Australia and the Pacific coast of Asia.
The samples are also likely concentrated in places where people were already concerned about PFAS contamination, Dr. O’Carroll said. He cautioned that, as a result, the findings of this new study may be skewed to show higher infection levels than a true global average. However, there is reason to believe that there is some level of PFAS contamination almost everywhere on the planet, he said.
Of the countries where studies were conducted, the United States and Australia had particularly high concentrations of PFAS in their water samples.
Among the available samples, the highest levels of contamination were generally found near places like airports and military bases, which commonly use PFAS-containing foam for firefighting practice. About 60 to 70 percent of both groundwater and surface water samples near these types of facilities had PFAS levels that exceeded the EPA Hazard Index, which measures how dangerous mixtures of certain chemicals can be to human health and also exceeded the limits in the EPA’s proposed new water consumption regulations.
This research does an admirable job of compiling the available data and highlighting the extent of global contamination by PFAS chemicals, said David Andrews, a senior scientist at the Environmental Working Group, a research and advocacy organization, who was not involved in this study. .
Scientific research on the health effects of PFAS has advanced significantly over the past 10 to 20 years, he said, and what are considered safe levels of exposure now are a small fraction of what they were a few decades ago.
The EPA’s proposed drinking water rules, depending on their final language, will be a big step forward, he said.
Michael Regan, the EPA administrator, said his agency plans to require utilities to treat their water so levels of some PFASs are near zero. This requirement would make the United States one of the strictest countries in regulating PFAS in water.
Dr Andrews added, however, that while drinking water treatment is important, it does not solve the whole problem. His own research has shown that PFAS chemicals are also pervasive in wildlife.
“Once they’re released into the environment, they’re incredibly difficult to clean up, if not impossible in many cases,” he said. “They can be removed from drinking water, but the ultimate solution is not to use them in the first place, especially in places where there are clear alternatives.”
For example, some outdoor clothing brands are moving away from PFAS for waterproofing their products and toward alternatives such as silicones. Fast food restaurants can wrap their burgers in paper that has been heat-treated to be resistant to grease or coated with PFAS-free plastic instead. The Department of Defense is beginning to replace traditional firefighting foam with an alternative called fluorine-free foam, or F3.
Meanwhile, Dr O’Carroll said: “I’m not in any way trying to say we shouldn’t drink water.” He added, “More of what I’m trying to say, from a social standpoint, we have to be careful what we put into the environment.”
