‘No Safe Level’: Babies Are Harmed by Even Tiny Amounts of Nitrate in Drinking Water, Study Finds

Even very low levels of nitrate in drinking water—far below the federal government’s safety threshold—may significantly increase the risk of premature birth and low birth weight, according to a new study.

Nitrate, a pervasive chemical that enters drinking water mainly through chemical fertilizer runoff and animal manure from farms, is invisible, odorless, and tasteless—leaving many people unaware they’re consuming it.

Researchers analyzed more than 350,000 birth records in Iowa from 1970 to 1988 and found that even 0.1 milligrams of nitrate per liter (mg/L)—a mere 1% of the level the Environmental Protection Agency (EPA) currently considers “safe”—was linked to higher risks of babies being born too early or too small.

Prematurity and low birth weight is the leading cause of death in newborns and children under age 5. It also raises the risk of developmental disorders like cerebral palsy, and the odds of chronic diseases like obesity and diabetes later in life.