Advanced PFAS water filters deliver unexpected health benefits by removing multiple toxic chemicals
Home water filters also offer protection when the public water supply is not filtered
• Broader impact: New research shows PFAS removal systems slash levels of cancer-causing disinfection byproducts by up to 50%, plus reduce heavy metals and agricultural nitrates in drinking water.
• Environmental inequity: Only 7% of small water systems serving fewer than 500 people use advanced filtration, compared to 28% of large utilities, leaving rural communities exposed to multiple contaminants.
• Policy gaps: The Environmental Working Group study calls for holistic water treatment strategies rather than regulating chemicals one at a time, as EPA rollbacks threaten recent PFAS protections.
Advanced water treatment systems designed to remove toxic "forever chemicals" from drinking water are delivering far greater health benefits than previously understood, eliminating multiple dangerous contaminants simultaneously, according to new peer-reviewed research.
The Environmental Working Group study, published today in ACS ES&T Water, analyzed data from 19 U.S. utilities and found that PFAS removal technologies such as granular activated carbon, ion exchange and reverse osmosis also significantly reduce levels of cancer-causing disinfection byproducts, agricultural nitrates and heavy metals including arsenic and uranium.
"PFAS treatment isn't just about 'forever chemicals,'" said Sydney Evans, EWG senior science analyst and lead author of the study. "It's also opening the door to improving water treatment across the board."
Treatment delivers dramatic reductions in toxic chemicals
In the 19 water systems studied, installation of advanced PFAS treatment led to an average 42% drop in trihalomethanes and a 50% reduction in haloacetic acids – both cancer-causing byproducts of water disinfection.
"These kinds of reductions caused by PFAS filters are a game changer for public health, especially since where there are PFAS, there are always other chemicals, too," said Varun Subramaniam, EWG science analyst and co-author.
The findings highlight how communities battling PFAS contamination face exposure to multiple harmful substances simultaneously, making comprehensive treatment approaches more valuable than addressing individual contaminants.
Small communities left behind in water treatment advances
The research exposed stark inequities in access to advanced filtration technology. While 28% of the largest water utilities have implemented sophisticated treatment systems, only 7% of very small systems serving fewer than 500 people use such technology.
This disparity leaves millions of Americans in rural and under-resourced communities exposed to PFAS, hazardous disinfection byproducts and heavy metals.
"This is a textbook case of environmental injustice," Subramaniam said. "The communities least able to afford advanced filtration often face the highest health risks. Without targeted investment, these gaps will only widen."
Federal policy changes threaten progress
The study's release comes as the EPA faces criticism for rolling back PFAS protections. In May, less than a year after finalizing new standards, the agency announced plans to weaken limits on four PFAS chemicals in drinking water and delay compliance deadlines.
"This study exposes a dangerous blind spot in federal water policy," said Melanie Benesh, EWG vice president of government affairs. "By ignoring these co-benefits, the EPA is leaving Americans exposed and missing a huge economic and public health opportunity."
Currently, only 8% of U.S. water systems have filters capable of removing PFAS, leaving millions vulnerable to health risks from multiple contaminants.
Health risks drive urgency for comprehensive solutions
PFAS, known as forever chemicals because they don't break down in the environment, are toxic at extremely low levels and have been detected in 99% of Americans' blood, including newborn babies, according to the Centers for Disease Control and Prevention.
Studies link PFAS exposure to immune system suppression, increased cancer risk, harm to fetal development and reduced vaccine effectiveness.
Home filters offer protection for individual households
While waiting for broader policy solutions, consumers can take action at home. EWG laboratory tests found four water filters that reduce detected PFAS in drinking water by nearly 100 percent, according to a separate 2023 EWG study that tested 10 popular home filtration systems.
EPA research confirms that granular activated carbon, ion exchange, and reverse osmosis point-of-use systems can greatly reduce PFAS levels, though filters are only effective when properly maintained and replaced according to manufacturer instructions.
Filters containing activated carbon or reverse osmosis membranes have been shown to be effective at removing PFAS from water supplies, according to the Minnesota Department of Health. However, the systems require regular maintenance to work properly.
The EWG testing showed that "while many of these filters work to remove PFAS, they will also filter out other contaminants in water" – supporting the new study's findings about co-benefits of PFAS treatment.
Policy recommendations target systemic change
The EWG study recommends federal and state leaders boost funding for advanced filtration in under-resourced systems, strengthen national water monitoring and adopt regulations accounting for co-occurring contaminants.
"This isn't just about PFAS," Evans said. "When we fix one problem, we can solve several others. The opportunity to protect public health at scale is too big to ignore – if we're smart about it."