The hormone-disrupting herbicide atrazine is contaminating nearly 25%, or about 860,000 miles, of all continental US rivers at levels that can harm wildlife and may threaten human health, a new review of federal records has found. The waterways cover over 20% of surface drinking water intakes across the country, and over 675,000 private and commercial wells. Atrazine can have severe impacts on human and animal hormones, especially for developing children. It was found to “chemically castrate” frogs, and cause some to change sexes. The herbicide is so dangerous that it has been effectively banned in 60 countries, including the European Union, since 2003. Atrazine can be particularly harmful to reproductive systems, and is linked to the “feminization” of the male gonads, irregular menstrual cycles, lower sperm counts, poor semen quality and lower fecundity in men and women. Among five hotspots where pollution is most concentrated are the Chesapeake Bay region, the midwest corn belt, Florida’s Lake Okeechobee, the lower Mississippi River and the Texas Gulf coast. In the midwest corn belt, including Kansas, Nebraska, Iowa, Missouri, Illinois, Indiana and Ohio, over two-thirds of river miles are contaminated, EPA records show, and that covers about half of the region’s wells and 68% of its drinking-water treatment facilities intakes. States in this region have rapidly rising early-onset cancer diagnoses compared with the rest of the country.