PFAS, also known as ‘forever chemicals,’ are extremely challenging to eliminate. These chemicals have been connected to environmental and health concerns, including certain types of cancer. However, there is still a lot that is not fully understood about the extent and potential effects of the issue, including the amount present in our water supply. A recent study examined the levels of PFAS contamination in surface and ground water worldwide and discovered that a significant portion of our global water sources exceeds safe drinking limits for PFAS.
Per-and poly-fluoroalkyl substances, commonly referred to as PFAS, are a group of over 14,000 artificially produced chemicals that have been widely used since the 1950s.
PFAS are known for their ability to resist heat, water, grease, and stains, making them widely used in household products such as non-stick frypans, clothing, cosmetics, insecticides, and food packaging. They are also used in specialty industry products like firefighting foam. However, despite their versatility, these chemicals have a downside: they are often referred to as ‘forever chemicals’ because once they enter the environment or our bodies, they do not break down any further. PFAS have been associated with environmental and health issues, including certain types of cancer, but there is still much that is not known about the full extent and potential impacts of these chemicals.The issue at hand concerns the amount of PFAS in our water supply. A recent international study led by UNSW and published in Nature Geoscience has evaluated PFAS contamination in surface and ground water worldwide. The study revealed that a significant portion of our global source water exceeds safe drinking limits for PFAS. According to senior author UNSW Engineering Professor Denis O’Carroll, “Many of our source waters are above PFAS regulatory limits.” This finding was surprising considering the pervasiveness of PFAS in the environment.”We’re talking about recommendations for avoiding drinking water,” he says. “The levels are above 5 percent, and in some cases, they exceed 50 percent.”
The research team gathered PFAS measurements from various sources worldwide, including government reports, databases, and peer-reviewed literature. In total, they compiled more than 45,000 data points spanning roughly 20 years.
This is the first study to assess the global environmental impact of PFAS.
The study also discovered high concentrations of PFAS in Australia, with many locations exceeding recommended drinking water levels. This was often in areas where firefighting activities occurred.The utilization of PFAS-containing fire-fighting foams has a history, primarily in military and fire training settings. Prof. O’Carroll points out that PFAS residues are detected in the source water, such as reservoirs, as opposed to the actual drinking water. Treatment plants are in place to mitigate the presence of chemicals like PFAS in our drinking water before it reaches us, but some water suppliers, like Sydney Water, don’t routinely test for a wide range of PFAS in our drinking water, according to Prof. O’Carroll. “Drinking water is mostly safe, and I don’t…”He advises against drinking it,” he says. “I also do not recommend that bottled water is superior, as it does not guarantee that any changes have been made compared to tap water.
“However, I do believe that it is important to monitor PFAS levels and make the data easily accessible.”
A controversial discussion: what constitutes an excessive amount of PFAS?
Most people in Australia – and in many other parts of the world – are likely to have minimal levels of PFAS in their bodies.
Yet, the potential health risks of PFAS chemicals are not well understood and there is no universal agreement on them.
According to an Australian GovernmentAccording to a government health panel, there is limited to no evidence that PFAS poses significant harm to human health. However, other sources in the US and Europe suggest a link between PFAS and adverse health outcomes such as lower birth weight, high cholesterol, kidney issues, thyroid disease, hormone level changes, reduced vaccine response, and various cancers. In 2023, the World Health Organization declared PFOA, a type of PFAS, a category one human carcinogen. While PFAS has been associated with these health outcomes, it may not necessarily be the direct cause.Paraphrasing the HTML article:
It has been demonstrated that certain chemicals, known as PFAS, can cause health issues. Due to the potential risks and the lasting impact of these chemicals, many regulatory bodies have tightened their control over the use of PFAS and have set safe limits for drinking water as a precaution.
Professor O’Carroll explained that two types of PFAS, PFOS and PFOA, initially raised concerns about 20 years ago. These chemicals are regulated to varying degrees across the globe. In the United States, proposed drinking water limits for PFOS and PFOA are set at four nanograms per liter.
In Australia, a third PFAS called PFHxS is also regulated, with the combined sum of PFOS and PFHxS being limited to 70 nanograms per liter, a significantly higher level than in the US.The combined PFOS and PFOA limit in the US is set at four nanograms per liter. However, the acceptable levels for PFOA in drinking water are even higher. According to Prof. O’Carroll, Australia regulates PFOA at 560 nanograms per liter, which is significantly higher than the US limit. In comparison, Canada’s recommended drinking water guidelines are even stricter, as they limit the overall number of 14,000 PFAS to 30 nanograms per liter, rather than just two or three forms.The research discovered that 69% of global groundwater samples without a known source of contamination exceeded the safe drinking water criteria set by Health Canada, while 32% of the same samples surpassed the proposed drinking water hazard index in the US.
“There’s ongoing discussion about the appropriate level at which PFAS should be regulated,” explained Prof. O’Carroll. “Australia has much higher limits than the US, but the question is, why?
“Both health organizations would have different justifications for this, and there isn’t a strong consensus at the moment.”
An underestimated danger
The study implies that actual PFAS pollution in global water resources is underestimated.
Levels of PFAS could be higher than previously thought.
One reason for this is that we only monitor and regulate a small number of the 14,000 PFAS that exist. Additionally, the levels of PFAS in consumer products are higher than expected.
According to Prof. O’Carroll, “There’s a significant amount of PFAS that we’re not measuring in the environment. Commercial products such as clothing and food packaging contain more PFAS than we realize.”
This suggests that we may be underestimating the environmental impact of PFAS.
Prof. O’Carroll and his team are now working to quantify these levels of PFAS in their research.
Scientists are currently working on developing technologies to decrease the presence of PFAS in the environment. They are also researching methods to degrade PFAS in drinking water systems and creating predictive models to track the movement of PFAS in the environment.
Professor O’Carroll stated, “We need to understand how PFAS interacts with different aspects of the environment and our bodies, such as proteins.” These research efforts are expected to continue for the next two years and are projected to be finished by 2026.
Meanwhile, Professor O’Carroll emphasizes the importance of both manufacturers and consumers being cautious and conducting thorough research when using products.
There are concerns about the widespread use of chemicals like PFAS, with experts noting that there hasn’t been a full assessment of their potential health impacts. It’s important to have judicious use of these chemicals and not assume that just because they’re available, they should be used.
Journal Reference:
- Diana Ackerman Grunfeld, Daniel Gilbert, Jennifer Hou, Adele M. Jones, Matthew J. Lee, Tohren C. G. Kibbey, Denis M. O’Carroll. Underestimated burden of per- and polyfluoroalkyl substances in global surface waters and groundwaters. Nature.
In Geoscience Journal, the article can be accessed at 10.1038/s41561-024-01402-8.