Per- and Poly fluoroalkyl substances found in nearly half of the U.S. tap water

CNN's news article: https://www.cnn.com/2023/07/05/health/pfas-nearly-half-us-tap-water-wellness/index.html 

Peer-reviewed article: https://www.sciencedirect.com/science/article/pii/S0160412023003069?via%3Dihub#f0005 

In recent years, growing concern has surrounded the presence of per- and polyfluoroalkyl substances (PFAS), often referred to forever chemicals in our environment and drinking water. These synthetic chemicals are widely used in consumer products for their resistance to water, oil, and heat but they do not easily break down in nature or the human body. Mounting evidence suggests that PFAS exposure may be linked to serious health outcomes, including cancer, thyroid disorders, and hormone disruption. In July 2023, a US Geological Survey study highlighted the presence of PFAS in nearly half of the tap water across the United Stated, capturing the attention of the media and the public.

CNN’s article provides a concise summary of the US Geological Survey study, emphasizing that about 45% of US tap water may contain at least one PFAS compound. Based on peer-reviewed research, the CNN article notes that only 32 out of more than 12,000 known PFAS chemicals were tested, suggesting that the actual exposure levels could be even higher. It also provides helpful context on health risks; ways individuals can reduce exposure and mentions regulatory steps being taken by the Environmental Protection Agency (EPA). However, the article does not delve deeply into the limitations of the study’s sampling strategy or the broader scientific uncertainty in assessing the full extent of contamination. It prioritizes accessibility and public awareness but could benefit greater attention to methodological details.

The peer reviewed article titled “Per- and polyfluoroalkyl substances in source and treated drinking waters of the United States” offers a detailed and rigorous scientific analysis. It involves sampling from 716 locations across the country from 2016 to 2021and provides both a detection frequency and concentration estimate of specific PFAS compounds. The authors openly discussed the limitations of the work including the restriction of 32 target PFAS, potential underestimation of exposure and geographic gaps in data. The study is careful not to overstate its conclusions and emphasizes the need for broader monitoring, more sensitive detection technologies and future studies to fill the remaining knowledge gaps.

Fig. 1. Per- and polyfluoroalkyl substances (PFAS) detections in point-of-use tap water collected from public-supply (blue circles) and private-wells (green triangles) across the United States including Puerto Rico and the U.S Virgin Islands. Samples with no detections are represented by open circles (public-supply) and triangles (private-wells).

While the CNN article effectively introduces the public to the issue of PFAS in drinking water, its main shortcoming lies in simplifying or omitting some of the complexities discussed in the peer-reviewed study. Although it does mention the limitation of only 32 PFAS being tested, it does not explore the potential for sampling bias or regional disparities in contamination. It also does not emphasize the scientific uncertainty surrounding PFAS health effects at low concentrations, which peer-reviewed study carefully notes.

I would rate this article 7 out of 10. The article accurately conveys the key facts and raises public awareness, but personally I think it could be improved by including more about the study’s design, limitations and the evolving nature of PFAS science. Overall, the article fairly represents the basic findings but lacks the nuance and caution present in the original research. It’s a good public communication piece but not a substitute for scientific depth.