Multitudes of Individuals in the U.S. Potentially Consuming Groundwater Contaminated with Persistent Chemicals
The next time you take a sip of water from your tap, you might want to ponder over its origin. Approximately 20% of the U.S. population might be consuming water contaminated with harmful toxins.
Per- and polyfluoralkyl substances (PFAs), often referred to as "forever chemicals," have gained notoriety due to their hard-to-degrade nature. For several years, the EPA has mandated monitoring of PFAs in water systems catering to over 3,300 people. However, the USGS discovered flaws in the data collected by the EPA. To gain a clearer picture of the extent of PFAs contamination in water supplies, the USGS researchers devised their own model, which they published in the journal Science. Their findings were disconcerting: They estimated that between 71 and 95 million people in the contiguous U.S. might be drinking water with detectable levels of these chemicals.
Underground water, commonly known as groundwater, is water stored in pores like aquifers. It can be supplied to households either via public utilities or private wells and serves as the main source of drinking water for around 107 million Americans.
The USGS research was based on over 1,200 groundwater samples collected between 2019 and 2022. The USGS scientists analyzed the data using machine learning algorithms, plotting the risk of contamination based on geographic location. This data was then compared to existing surveys detailing the reliance on groundwater for drinking purposes in various regions.
In terms of raw numbers, Florida and California have the highest population at risk, with 9.5 million and 13 million people, respectively, potentially consuming contaminated public water. On a per capita level, Massachusetts takes the lead, with an alarming 86-98% of the population relying on groundwater supplies vulnerable to contamination.
Andrea Tokranov, a research hydrologist at the USGS who spearheaded the study, highlighted a positive aspect. The new model can help pinpoint areas requiring further testing to ensure individuals are not unknowingly consuming contaminated water. This is particularly crucial for private well users, who may not have access to regional water quality information or testing facilities.
While some research suggests PFAs could have negative health impacts, there is still much we don't know. The CDC cautions that many animal studies involving PFAs exposure utilize higher doses than typical human exposure levels. The effects of PFAs can also vary based on frequency and dose of exposure, and individual health, water access, and other factors.
Nonetheless, there have been links found between PFAs and several severe health conditions in humans. Issues such as fertility problems, developmental delays in children, higher cholesterol levels, weakened immune responses, and increased risks of prostate, kidney, and testicular cancer have been associated with PFAs exposure, as per the EPA.
To facilitate easy access to the data, the USGS also launched an interactive map, depicting the likelihood of PFA contamination in local groundwater supplies. Users should note that the map represents a mathematical model and is not definitive. Furthermore, the results may not accurately reflect the PFA levels in your tap water.
Finding a silver lining, the USGS findings are relatively better than their report from last year. In that study, PFAs were detected in water samples from 716 kitchen sinks, suggesting that around 47% of the population was consuming water with PFAs. In a twisted sense, this could be considered progress.
The USGS research predicts that advanced technology and science might be crucial in the future to address PFAs contamination in water supplies, as machine learning algorithms were instrumental in their study. Regular health check-ups could become more important in the future due to potential health risks associated with PFAs exposure, such as fertility problems and increased cancer risks.
