About 95 percent of the US population is drinking water from wells and community systems containing unsafe levels of toxic contaminants, a new study has revealed.
Scientists at the University of New Mexico identified at least six pollutants, primarily arsenic, nitrates, uranium and lead, linked to neurological and developmental problems.
Fracking fluids and PFAS were also detected in the drinking water that also flows to the homes of about 320 million Americans.
The six contaminants represent a small fraction of the thousands of chemical agents present in drinking water, the authors report.
The team also warned that two or more contaminants could be present in a water source, ‘presenting the possibility of synergistic effects,’ the researchers said.
About 95 percent of the US population is drinking water from wells and community systems containing unsafe levels of toxic contaminants, a new study has revealed. Pictured is a map showing Tribal population locations, which are hit the hardest by toxins in waters
‘The seven contaminants and contaminant groups presented here represent a tiny fraction of the thousands of regulated and unregulated chemical agents present in drinking water,’ reads the study published in Nature.
‘This review illustrates the complexities of the array of chemical hazards in our drinking water and highlights the need for a concerted effort to invest in upgrading our drinking water infrastructure, strengthen drinking water standards, develop and implement enhanced water treatment, collect and disseminate monitoring data, and require more stringent chemical safety testing to support the welfare of all US residents.’
Arsenic
The team found arsenic is detectable in more than 50 percent of Community Water Systems (CWSs), with 2.6 percent exceeding the Maximum Contaminant Level (MCL).
These high levels were found in the US’s Southwest and Great Plains regions, where hard rock mining processes and mine waste occur.
Arsenic has long been flowing through drinking water systems, but while the MCL is 0.010 micrograms/liter (µg/L), parts of the US have seen higher levels.
The team found arsenic is detectable in more than 50 percent of Community Water Systems (CWSs), with 2.6 percent exceeding the Maximum Contaminant Level. This map shows estimates of how many private domestic well users in each county may be drinking water with levels of arsenic of possible concern for human health
The study highlights that from 2009 through 2011, the average arsenic concentrations were 1.70 µg/L nationwide.
The highest were located in communities categorized as Semi-Urban, Hispanic (3.40 µg/L); communities in the Southwestern US (3.18 µg/L); communities with less than 500 residents; communities reliant on groundwater sources; and incarcerated populations in the Southwest (2006–2011, mean 6.41 µg/L),’ the researches shared.
Repeated exposure can damage DNA, weaken the immune system and lead to the formation of cancer cells, as well as high blood pressure and heart disease.
Lead
Detections of lead stem from America’s history of using the material for water system pipes during the 1800s.
However, lead pipes continued to be installed in the US until they were banned in 1986, including in locales such as Chicago that required lead service line installation until then.
The six contaminants represent a small fraction of the thousands of chemical agents present in drinking water, the authors report
The Environmental Protection Agency (EPA) does not have a set MCL for lead but established a Treatment Technique requiring systems to control the corrosiveness of their water.
If more than 10 percent of the tap water samples exceed the Action Level (AL) of 0.015 mg/L, water systems must take additional steps – part of the Lead and Copper Rule (LCR).
The study highlights research conducted in 2021 that found 186 million Americans receive water from CWSs with detectable lead contamination.
And a majority of these people live in minoritized and low-income communities.
Lead is also highly toxic and associated with adverse health endpoints across virtually all body systems, including nervous, cardiovascular, renal, immunological, hematological and reproductive/developmental systems in men and women, in adults and children.
Uranium
Uranium occurs naturally in Earth’s crust, which leaches into water systems through geochemical processes.
Previous studies have shown that 74 percent of Americans have traces of the substance in their urine, and in the human body, it accumulates in the bone and the kidneys.
Uranium occurs naturally in Earth’s crust, which leaches into water systems through geochemical processes. The EPA’s map (pictured) shows elevated uranium levels in two-thirds of community water systems
Alpha radiation from uranium decay is classified as carcinogenic, and increasing epidemiological evidence shows that exposure to uranium in its metallic form is associated with chronic kidney disease and neurologic, reproductive and cardiovascular toxicity.
According to data from the US National Water Information System (NWIS), 50 percent of domestic wells in the US have detectable concentrations of uranium.
Nitrates
‘Nitrate levels in water resources have increased worldwide from applications of inorganic fertilizer and animal manure in agricultural areas,’ the study reads.
‘Contamination sources also include septic systems that do not effectively remove nitrogen and discharges from wastewater treatment plants, as well as atmospheric deposition of nitrogen oxides and fertilizer use on lawns, golf courses, and parks.’
The team found that in 2019 about 5.6 million Americans were exposed to levels over the maximum limit.
These levels were primarily detected in the Yakima Valley of Washington State and the San Joaquin Valley of California.
Consuming too much nitrate can affect how blood carries oxygen and cause methemoglobinemia, when the hemoglobin can carry oxygen but cannot release it effectively to body tissues.
Fracking-related substances
These substances are derived from oil and gas extracted deep underground through wells.
There are 150,000 active wells nationwide, and more than nine million Americans rely on drinking water sources within one mile of these sites.
Fracking fluids and wastewater from the process can contain toxic, radioactive and carcinogenic chemicals.
And the study notes that up to four percent of spills go unreported.
PFAS
Per- and polyfluoroalkyl substances (PFAS) are synthetic chemical compounds used in cleaning products, certain fabrics, non-stick cookware and other items.
According to the National Health and Nutrition Examination Survey (NHANES), over 98 percent of the US population has detectable levels of PFAS in their blood.
‘The highest levels of PFAS in drinking water have been found close to industrial facilities where PFAS are manufactured or processed and sites with discharges of aqueous film forming foam (AFFF) at military bases, major airports, and other fire training areas,’ according to the authors.
The study shared that up to 80 million Americans get water that is tainted with high concentrations of PFAs.
In 2023, the EPA estimated that from 70 to 94 million people in the US are exposed to six PFAS of concern in their drinking water at elevated levels.
