Mercury pollution in rivers worldwide has surged to three times its natural levels since the dawn of the Industrial Revolution — a rise fueled by coal combustion, mining, and manufacturing, according to a new study published in Science. Researchers warn that this trend poses a growing threat to ecosystems and public health.
Using historical data and sediment core analysis, scientists estimate that rivers transported around 390 megagrams of mercury annually in the mid-19th century. Today, that number has soared to nearly 1,000 megagrams per year — a 150% increase. This neurotoxic metal, once released into waterways, accumulates in fish and travels up the food chain, posing serious health risks to humans, especially pregnant women and children.
Dr. Yanxu Zhang, co-author of the study and professor at Tulane University, explained that mercury exposure can cause neurological damage, vision and hearing loss, and developmental issues in infants. The most common source of human exposure? Eating contaminated fish.
Yet even as mercury levels rise, U.S. environmental protections are being weakened. In recent months, EPA Administrator Lee Zeldin has rolled back key regulations, including the Mercury and Air Toxics Standards (MATS), which had previously curbed emissions from power plants. Critics, including scientists and legal experts, warn these policy reversals will endanger public health.
Regions with heavy industrial activity, such as those in the eastern United States, are especially vulnerable. Minnesota has already advised residents to limit fish consumption from mercury-contaminated waters.
“This study is another red flag,” said John Holdren, former White House science adviser. “Mercury isn’t just dangerous — it’s persistent, cumulative, and entirely preventable.”
As mercury continues to build in our waterways, experts stress the urgent need for science-based policy to protect both people and the planet.
