Latest news with #VasilisVasiliou
Miami Herald
11-07-2025
- Health
- Miami Herald
What's Contaminating Water Across All 50 States? Full List
Six contaminants found in drinking water across every U.S state exceeded legal guidelines set by the federal government, a study revealed. In the 50,000 water systems surveyed in the study by the Environmental Working Group (EWS) between 2021 and 2023, there were 324 contaminants found in drinking water-12 of which were found across all 50 states. While in many states the contaminants were below the Environmental Protection Agency (EPA)'s maximum contaminant level (MCL) guidelines, in some regions, the contaminants were higher, posing a risk to public health. "Since the passage of the Safe Drinking Water Act, 50 years ago, drinking water utility operators have been working day-in and day-out to meet the regulatory requirements, including testing and treating for over 90 contaminants regulated under the Safe Drinking Water Act," the EPA told Newsweek. "The large majority of water systems [over 90 percent of active public water systems] are meeting health-based standards, and are providing clean, safe drinking water to customers." Of the 12 contaminants found by EWS, Newsweek has investigated the contaminants the EPA regulates-which does not include chlorate, manganese, molybdenum and vanadium. Chromium was an identified contaminant the EPA does regulate across all states, but no water systems reviewed by EWS had levels higher than the EPA's current MCL. While the EPA has an MCL for radioactive strontium-90, a metal that may cause bone cancer and leukemia, according to EWS, the element has a number of other isotopes that have not been given an MCL-the EWS did not specify which isotope was detected in all 50 states. Arsenic is a natural element found in soils, sediments and groundwater that can feed into water systems. The EWS found that for 481,000 Americans across 29 states, levels of arsenic in drinking water exceeded the legal limit. Utility services in California, New Mexico, Michigan and Texas had some of the highest levels of arsenic in drinking water that were significantly above the EPA's MCL of 10 micrograms per liter. Other studies have highlighted the risk of arsenic in drinking water at levels even below the EPA's maximum contaminant level, finding that even very low levels of arsenic exposure had impacts on birth outcomes, such as low birth weight and preterm births. About 7.6 percent of American water systems have levels of arsenic that exceed the EPA's MCL, while other states have implemented their own reduced MCLs, like New Hampshire and New Jersey, Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek. He added that arsenic is a "known carcinogen," according to an International Agency for Research on Cancer (IARC) report, and is also "linked to cardiovascular disease and developmental neurotoxicity." Arsenic is also "difficult to remove from drinking water," Natalie Exum, a professor in the Department of Environmental Health and Engineering at Johns Hopkins Bloomberg School of Public Health, told Newsweek. It is a "struggle, especially for small community water systems, to remain in compliance with the MCL or rural communities that are on private wells and not regulated under the Safe Drinking Water Act," she added. That means many low-income, rural communities are "exposed to unsafe levels," Exum said. Barium, a mineral found in rocks, soil and water, can increase the risk of cardiovascular disease and hypertension in high concentrations, EWS said. Per EWS' findings, 298 Americans-most of whom were in New York and Pennsylvania-are being exposed to levels of barium in drinking water that surpassed the EPA's maximum contaminant level of 2,000 micrograms per liter. The issue of fluoride in drinking water has been widely debated in the U.S., and recently a number of states like Utah and Florida have banned it from water systems. It was originally added to water systems to combat tooth decay but more recently has been scrutinized by critics citing studies that elevated exposure could reduce IQ levels in children. As a result of the new research on its possible impacts, "this MCL is in need of revision and water supplies need to be routinely tested for natural sources of fluoride," Vasiliou said. "Private well owners need to test for fluoride as well." The EPA's current MCL for the compound is 4,000 micrograms per liter, and according to EWS, more than 18,000 Americans are drinking water with levels higher than that, with one water utility in California having levels of 12,000 micrograms per liter on average. Haloacetic acids are formed when disinfectants such as chlorine are added to tap water, EWS reported. Long-term exposure to high levels of the acids has been linked to cancer and birth defects, according to the water filtration company Spring Well Water. The EPA's MCL for haloacetic acids in drinking water is 60 micrograms per liter, and according to EWS, almost 400,000 Americans are drinking water with levels higher than that, with water utilities in Georgia, Virginia, Louisiana, Alaska, Oklahoma and Washington all having levels higher than 100 micrograms per liter. Radium, a radioactive element that can naturally occur in groundwater, but may also be elevated by oil and gas extraction activities, was found in water systems across all 50 states. The EWS reported that it may cause bone and other cancers, and that more than 100,000 Americans were drinking water with levels of radium higher than the EPA MCL of 5 picoCuries per liter. In water utilities in Texas and Colorado, levels of radium were found well above even double the EPA's limit. Vasiliou said that radium tends to be found mostly in smaller and more rural water systems, and that testing in rural systems and private wells should be "prioritized." Trihalomethanes (TTHMs) are formed in drinking water during the water treatment process and are a human carcinogen, EWS said. While the EPA's MCL of TTHMs is 80 micrograms per liter, more than 400,000 Americans are drinking water that exceeds the legal limit, according to EWS, with highest elevated levels found across Louisiana, Florida, Texas and California. Vasiliou said that TTHMs are "detected in nearly all public water supplies," and are "associated with bladder cancer, liver and kidney toxicity, and potential developmental harm." "We do not do a good job of protecting our source waters in the U.S.," Exum said. "We have allowed industries to dispose of waste in the environment that has permanently contaminated drinking water sources." She said most of the chemical contaminants in the EWG Tap Water Database are measured at the treatment plant, meaning that "your water has a long journey to make through a lot of pipes underground before it gets to your tap." "Given our aging drinking water in the U.S., this allows for contamination that often goes unmeasured, especially lead," she said. For that reason, Exum recommended water filters that are NSF/ANSI Standard 53 for those in urban communities especially to reduce "health-related contaminants in drinking water." Susan Richardson, a professor of chemistry at University of South Carolina, told Newsweek: "I personally would be mostly concerned about arsenic, and disinfection by-products like haloacetic acids and trihalomethanes. "There are many epidemiologic studies showing documented human health effects for these, and many of these can cause cancer." She added that she would recommend using water filters if levels "exceed regulatory or guideline limits" for contaminants. "If levels are close to the limits, women who are pregnant or other people who are immunocompromised might want to take extra precautions and use a water filter," Richardson said. "But, for sure you don't need to use one everywhere." Exum also warned that there is some concern that the current MCL for nitrate, a contaminant found in 49 states, according to EWS data, "does not fully protect against the risk of cancer and harm to the developing fetus," adding she thought the MCL "should be re-examined now that so many communities in the U.S. are exposed as meaningful levels." Despite calls for the EPA to change its MCL for a number of contaminants in U.S. drinking water, as the EPA previously explained to Newsweek, it's not that simple. "There is legitimate debate about whether the financial costs, inconvenience and health concerns of bottled water and filters are really an improvement over publicly supplied tap water," said Marc Edwards, a professor in civil and environmental engineering at Virginia Tech. He pointed to a United Nations University report that documented many instances in which bottled water was found to be contaminated with plastics and even worse contaminants. He added that he would not read the EWS report and "come away with increased distrust of my tap water, unless the levels are above or are at least close to federal standards." In those cases where levels are elevated, "filters and bottled water should be strongly considered," Edwards said. Related Articles Owner Confused by Cat's Way of Drinking Water, Then She Realizes WhySadhguru Pinpoints America's Drinking Water ProblemsCalifornia Has a Drinking Water ProblemPregnant Women Issued Drinking Water Warning 2025 NEWSWEEK DIGITAL LLC.
Newsweek
11-07-2025
- Health
- Newsweek
What's Contaminating Water Across All 50 States? Full List
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. Six contaminants found in drinking water across every U.S state exceeded legal guidelines set by the federal government, a study revealed. In the 50,000 water systems surveyed in the study by the Environmental Working Group (EWS) between 2021 and 2023, there were 324 contaminants found in drinking water—12 of which were found across all 50 states. While in many states the contaminants were below the Environmental Protection Agency (EPA)'s maximum contaminant level (MCL) guidelines, in some regions, the contaminants were higher, posing a risk to public health. "Since the passage of the Safe Drinking Water Act, 50 years ago, drinking water utility operators have been working day-in and day-out to meet the regulatory requirements, including testing and treating for over 90 contaminants regulated under the Safe Drinking Water Act," the EPA told Newsweek. "The large majority of water systems [over 90 percent of active public water systems] are meeting health-based standards, and are providing clean, safe drinking water to customers." Of the 12 contaminants found by EWS, Newsweek has investigated the contaminants the EPA regulates—which does not include chlorate, manganese, molybdenum and vanadium. Chromium was an identified contaminant the EPA does regulate across all states, but no water systems reviewed by EWS had levels higher than the EPA's current MCL. While the EPA has an MCL for radioactive strontium-90, a metal that may cause bone cancer and leukemia, according to EWS, the element has a number of other isotopes that have not been given an MCL—the EWS did not specify which isotope was detected in all 50 states. Photo-illustration by Newsweek/Getty/Canva Arsenic Arsenic is a natural element found in soils, sediments and groundwater that can feed into water systems. The EWS found that for 481,000 Americans across 29 states, levels of arsenic in drinking water exceeded the legal limit. Utility services in California, New Mexico, Michigan and Texas had some of the highest levels of arsenic in drinking water that were significantly above the EPA's MCL of 10 micrograms per liter. Other studies have highlighted the risk of arsenic in drinking water at levels even below the EPA's maximum contaminant level, finding that even very low levels of arsenic exposure had impacts on birth outcomes, such as low birth weight and preterm births. About 7.6 percent of American water systems have levels of arsenic that exceed the EPA's MCL, while other states have implemented their own reduced MCLs, like New Hampshire and New Jersey, Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek. He added that arsenic is a "known carcinogen," according to an International Agency for Research on Cancer (IARC) report, and is also "linked to cardiovascular disease and developmental neurotoxicity." Arsenic is also "difficult to remove from drinking water," Natalie Exum, a professor in the Department of Environmental Health and Engineering at Johns Hopkins Bloomberg School of Public Health, told Newsweek. It is a "struggle, especially for small community water systems, to remain in compliance with the MCL or rural communities that are on private wells and not regulated under the Safe Drinking Water Act," she added. That means many low-income, rural communities are "exposed to unsafe levels," Exum said. Barium Barium, a mineral found in rocks, soil and water, can increase the risk of cardiovascular disease and hypertension in high concentrations, EWS said. Per EWS' findings, 298 Americans—most of whom were in New York and Pennsylvania—are being exposed to levels of barium in drinking water that surpassed the EPA's maximum contaminant level of 2,000 micrograms per liter. Fluoride The issue of fluoride in drinking water has been widely debated in the U.S., and recently a number of states like Utah and Florida have banned it from water systems. It was originally added to water systems to combat tooth decay but more recently has been scrutinized by critics citing studies that elevated exposure could reduce IQ levels in children. As a result of the new research on its possible impacts, "this MCL is in need of revision and water supplies need to be routinely tested for natural sources of fluoride," Vasiliou said. "Private well owners need to test for fluoride as well." The EPA's current MCL for the compound is 4,000 micrograms per liter, and according to EWS, more than 18,000 Americans are drinking water with levels higher than that, with one water utility in California having levels of 12,000 micrograms per liter on average. Haloacetic acids Haloacetic acids are formed when disinfectants such as chlorine are added to tap water, EWS reported. Long-term exposure to high levels of the acids has been linked to cancer and birth defects, according to the water filtration company Spring Well Water. The EPA's MCL for haloacetic acids in drinking water is 60 micrograms per liter, and according to EWS, almost 400,000 Americans are drinking water with levels higher than that, with water utilities in Georgia, Virginia, Louisiana, Alaska, Oklahoma and Washington all having levels higher than 100 micrograms per liter. Radium Radium, a radioactive element that can naturally occur in groundwater, but may also be elevated by oil and gas extraction activities, was found in water systems across all 50 states. The EWS reported that it may cause bone and other cancers, and that more than 100,000 Americans were drinking water with levels of radium higher than the EPA MCL of 5 picoCuries per liter. In water utilities in Texas and Colorado, levels of radium were found well above even double the EPA's limit. Vasiliou said that radium tends to be found mostly in smaller and more rural water systems, and that testing in rural systems and private wells should be "prioritized." Total Trihalomethanes (TTHMs) Trihalomethanes (TTHMs) are formed in drinking water during the water treatment process and are a human carcinogen, EWS said. While the EPA's MCL of TTHMs is 80 micrograms per liter, more than 400,000 Americans are drinking water that exceeds the legal limit, according to EWS, with highest elevated levels found across Louisiana, Florida, Texas and California. Vasiliou said that TTHMs are "detected in nearly all public water supplies," and are "associated with bladder cancer, liver and kidney toxicity, and potential developmental harm." What The Experts Say "We do not do a good job of protecting our source waters in the U.S.," Exum said. "We have allowed industries to dispose of waste in the environment that has permanently contaminated drinking water sources." She said most of the chemical contaminants in the EWG Tap Water Database are measured at the treatment plant, meaning that "your water has a long journey to make through a lot of pipes underground before it gets to your tap." "Given our aging drinking water in the U.S., this allows for contamination that often goes unmeasured, especially lead," she said. For that reason, Exum recommended water filters that are NSF/ANSI Standard 53 for those in urban communities especially to reduce "health-related contaminants in drinking water." Susan Richardson, a professor of chemistry at University of South Carolina, told Newsweek: "I personally would be mostly concerned about arsenic, and disinfection by-products like haloacetic acids and trihalomethanes. "There are many epidemiologic studies showing documented human health effects for these, and many of these can cause cancer." She added that she would recommend using water filters if levels "exceed regulatory or guideline limits" for contaminants. "If levels are close to the limits, women who are pregnant or other people who are immunocompromised might want to take extra precautions and use a water filter," Richardson said. "But, for sure you don't need to use one everywhere." Exum also warned that there is some concern that the current MCL for nitrate, a contaminant found in 49 states, according to EWS data, "does not fully protect against the risk of cancer and harm to the developing fetus," adding she thought the MCL "should be re-examined now that so many communities in the U.S. are exposed as meaningful levels." Despite calls for the EPA to change its MCL for a number of contaminants in U.S. drinking water, as the EPA previously explained to Newsweek, it's not that simple. "There is legitimate debate about whether the financial costs, inconvenience and health concerns of bottled water and filters are really an improvement over publicly supplied tap water," said Marc Edwards, a professor in civil and environmental engineering at Virginia Tech. He pointed to a United Nations University report that documented many instances in which bottled water was found to be contaminated with plastics and even worse contaminants. He added that he would not read the EWS report and "come away with increased distrust of my tap water, unless the levels are above or are at least close to federal standards." In those cases where levels are elevated, "filters and bottled water should be strongly considered," Edwards said.
Newsweek
20-06-2025
- Health
- Newsweek
Map Shows States Where Drinking Water Contamination is Highest
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. A new study by researchers at Columbia University has revealed the states that have higher rates of arsenic in public drinking water systems, most of which are in the West and Midwest. Michigan, South Dakota, Nevada, and California were all states that had areas with levels of higher than 5 micrograms per liter of arsenic in the drinking water. The study found that even low levels of arsenic in drinking water may increase the risk of below average birth weight and other adverse birth outcomes. Why It Matters Arsenic is a natural element that can be found in soils, sediments, and groundwater, meaning it can feed into public drinking water systems. Water sources in some parts of the U.S. have higher naturally occurring levels of inorganic arsenic than other areas, according to the Environmental Protection Agency (EPA). At high levels, exposure to arsenic can cause symptoms ranging from nausea, vomiting, and diarrhea to dehydration and shock. Long-term exposure has been associated with skin disorders and increased risks for diabetes, high blood pressure, and several types of cancer. While EPA has determined that there is a safe level of exposure at less than 10 micrograms per liter, the new study suggests that the maximum level of accepted arsenic exposure may still be associated with health risks. A map showing the levels of arsenic in drinking water in different locations. A map showing the levels of arsenic in drinking water in different locations. Uncredited/JAMA Network What To Know The study was conducted via review of 14,000 pregnancies across 35 cohort sites participating in the National Institutes of Health's Environmental influences on Child Health Outcomes (ECHO) program, and its findings were published on the medical journal site JAMA Network earlier this week. It also assessed the level of arsenic in public drinking water systems in various areas nationwide—based on data from 2017 to 2019, with the exception of Michigan, as data was not available in that time period for the state and instead was taken from 2009 to 2011. The findings, as shown in the map above, revealed that Western and Midwestern states were more likely to have higher levels of arsenic in public drinking water. The disparity is because some states "have elevated arsenic levels primarily due to natural geology, with some contribution from human activities," Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek. "Arsenic naturally leaches from rocks into groundwater in regions with volcanic, mineral-rich, or sedimentary formations," which is common in the Southwest, Midwest, and parts of California's Central Valley, he said. "Many affected communities depend on groundwater-fed wells, which are more prone to arsenic contamination than surface water," he added. Vasiliou said that agricultural runoff and irrigation practices were also factors at play, particularly in areas like California's Central Valley or Nebraska's farming regions. "Small rural and Indigenous communities often bear the highest burden, especially those relying on underfunded or poorly monitored water systems," he added. "Many small water systems lack the capacity for frequent testing or advanced arsenic removal. Without federal or state investment, meaningful reduction in exposure is unlikely," Vasiliou said. While the EPA continues to maintain that exposure to arsenic in drinking water at a level of less than 10 micrograms per liter "protects public health based on the best available science and ensures that the cost of the standard is achievable," some states have taken measures into their own hands. New Jersey and New Hampshire have since enacted stricter limits of 5 micrograms per liter. "The 10 micrograms per liter limit is a political and economic compromise, not a health-based standard, and likely insufficient to fully protect the public, especially over a lifetime of exposure," Vasiliou said. What People Are Saying Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek: "Even at low-to-moderate levels of chronic exposure (e.g., 5—10 µg/L), arsenic has been linked to cardiovascular disease, including increased risk of high blood pressure, atherosclerosis, and ischemic heart disease—possibly due to endothelial damage and oxidative stress. It has also been linked to type 2 diabetes, as arsenic can impair pancreatic β-cell function and glucose metabolism. Low-level exposure has also been associated with reduced cognitive performance, particularly in children, and possibly neurodegeneration in older adults. Chronic exposure, even at levels near or below the EPA maximum, has been linked to bladder, lung, skin, and possibly kidney and liver cancers. Arsenic disrupts immune function as well, increasing susceptibility to infections and possibly reducing vaccine effectiveness." He added: "The current EPA maximum contaminant level of 10 µg/L was set in 2001, and enforced in 2006, based largely on cancer risk, balancing feasibility and cost. However, more recent studies suggest adverse health effects at levels well below 10 µg/L, especially for sensitive populations. A growing number of researchers argue that no safe threshold may exist for certain outcomes like prenatal exposure, cardiovascular disease, and cancer." What Happens Next The authors of the study called for further research to determine the influence of arsenic on public health, and stressed the importance of updating health-based water safety standards at both federal and state levels.
Newsweek
19-06-2025
- Health
- Newsweek
America's Drinking Water is Changing How Babies Are Being Born: Study
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. Even low levels of arsenic in U.S. public drinking water may increase the risk of below average birth weight and other adverse birth outcomes, says a new national study led by researchers at Columbia University. The findings, drawn from nearly 14,000 pregnancies across 35 cohort sites participating in the National Institutes of Health's Environmental influences on Child Health Outcomes (ECHO) program, were published on the medical journal site JAMA Network earlier this week. "It is concerning, but what really stands out as major concern from this study is that no exposure level seems truly safe during pregnancy," Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek. Newsweek has contacted the EPA via email for comment. Why It Matters The research addresses growing concerns about the adequacy of U.S. drinking water safety standards, particularly for vulnerable populations. The findings suggest that health risks may occur from exposure below levels currently considered safe by the Environmental Protection Agency's (EPA) arsenic limit that was determined in 2001. The study also said that low birth weight and preterm birth are "important predictors of infant mortality and morbidity across the life span," highlighting that low-level exposure to arsenic in drinking water could have prolonged and even fatal impacts. File photo: a young girl drinks some water from a bottle. File photo: a young girl drinks some water from a bottle. Nicolas Messyasz/Sipa via AP What To Know The study found that prenatal exposure to arsenic—even below the current federal standard of 10 micrograms per liter—was linked to a higher likelihood of babies being born preterm, with lower birth weights, or smaller than expected for their gestational age. Preterm birth was noted when a baby had a gestational age of less than 37 weeks, and low birth weight was identified as a weight of less than 2500 grams, or 2.5 kilograms. Both outcomes were observed across multiple racial and ethnic groups, including White, Black, Hispanic/Latino, American Indian, Alaska Native, Native Hawaiian, and Pacific Islander families. The authors noted that the risk of low birth weight following prenatal exposure to arsenic was higher among White, Black and Hispanic/Latino birthing parents. "Arsenic's toxicity during pregnancy is multifactorial, involving oxidative stress, epigenetic disruption, placental toxicity, immune dysregulation, and hormonal interference—all of which can independently or jointly lead to low birth weight, preterm birth, and developmental programming of chronic disease," Vasiliou told Newsweek. In 2001, the EPA announced its 10 micrograms per liter standard for arsenic. At the time, the EPA Administrator, Christine Todd Whitman, stated that "the 10 ppb protects public health based on the best available science and ensures that the cost of the standard is achievable." However, some states, such as New Jersey and New Hampshire, have since enacted stricter limits of 5 micrograms per liter. "Arsenic is released from rocks and soil into groundwater, which then feeds into municipal supplies," Vasiliou said. He added that regions like the Southwest, parts of New England, Minnesota, and Wisconsin "are known for elevated natural levels." Human activities like mining, agriculture, and industrial processes "can raise arsenic levels in nearby water systems," he said. What People Are Saying Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek: "I believe that based on this, the EPA should consider lowering the maximum contaminant level below 10 µg/L. The authors explicitly recommend this as a way to help reduce low‑birth weight rates. More frequent testing of public water systems, especially in high‑risk locales, along with investment in treatment technologies, for example coagulation, adsorption, ion exchange, will be essential. Communities with elevated but sub-limit arsenic should be informed about risks, and pregnant people encouraged to use alternative water sources or filtration. I believe that we should continue monitoring birth outcomes in relationship to low-dose arsenic exposure and refine risk estimates across different demographics." He added: "Arsenic isn't the only chemical of concern in tap water; I can list PFAS, 2,4-dioxane and other emerging chemical contaminants. Therefore, pregnant people often face multiple low-level exposures. Even small reductions in one contaminant can yield meaningful health improvements when cumulative." What Happens Next The study's authors urged for further research to dissect the combined influence of arsenic and other social determinants of health. They also stressed the importance of reviewing legacy contaminants like arsenic and updating health-based water safety standards at both federal and state levels.
