A groundbreaking new study has found concerning links between chemical contaminants in drinking water and increased cancer risk across multiple organ systems. The research, published in January 2025, examined the relationship between per- and polyfluoroalkyl substances (PFAS) in drinking water and cancer rates across U.S. counties.
PFAS are synthetic chemicals that have been widely used in consumer products since the 1940s. Due to their resistance to breaking down, these “forever chemicals” have accumulated in the environment, with drinking water being a major exposure source for the general population.
The study analyzed cancer data from 2016-2021 across regions covering approximately half of the U.S. population. The researchers found that areas with PFAS-contaminated drinking water had higher rates of several types of cancer, including:
- Digestive system cancers (including esophageal, colorectal, liver, and gallbladder cancers)
- Thyroid cancer
- Oral and throat cancers
- Lung cancer
The associations were particularly strong for certain PFAS compounds. For example, one type called PFBS was linked to a 33% higher risk of oral and throat cancers. The study estimated that PFAS in drinking water may contribute to between 4,600 and 6,800 new cancer cases each year in the United States.
Interestingly, the effects appeared to differ between men and women. In men, PFAS exposure was more strongly associated with urinary system cancers, brain cancer, leukemia and soft tissue cancers. In women, the strongest links were seen with thyroid cancer and cancers of the mouth and throat.
The findings come as the U.S. Environmental Protection Agency (EPA) has taken steps to regulate PFAS in drinking water. In April 2024, the EPA announced the first-ever national drinking water standards for six PFAS compounds.
The study authors note that while their research shows concerning associations, more work is needed to fully understand how PFAS exposure may lead to cancer development. They emphasize that their findings highlight the critical importance of developing effective strategies to reduce PFAS contamination in drinking water.
Comments: Given the growing concerns about PFAS and other contaminants in drinking water, installing a high-quality water filtration system has become increasingly important for protecting household health. While municipal water treatment facilities work to meet basic safety standards, they may not fully address all potential contaminants, particularly emerging concerns like PFAS.
When selecting a water filtration system, it’s important to look for NSF certification and verification that the system can reduce PFAS and other concerning chemicals. The filter’s micron rating is also crucial. Systems with ratings of 0.5 microns or less are generally more effective at removing the smallest contaminants.
While the initial investment in a quality filtration system may seem significant, it should be viewed as a critical health protection measure. The long-term costs of potential health impacts from contaminated water far outweigh the expense of proper filtration. Additionally, using filtered water for both drinking and cooking is essential, as many contaminants can become more concentrated during the cooking process.
