Atrazine contaminates a quarter of U.S. river miles, raising cancer concerns
A new analysis shows the cancer-linked herbicide atrazine is present in roughly 25% of river and stream miles across the lower 48 states, including many sources of drinking water.
An analysis by the Center for Biological Diversity, based on EPA monitoring, reveals that atrazine— a herbicide banned in over 60 nations and associated with cancer and endocrine disruption—pollutes an estimated 25% of river and stream miles in the contiguous United States. The study highlights that concentrations often exceed the EPA’s ecological limit of 9.7 ppb, with especially high levels in the Chesapeake Bay, the Midwest Corn Belt, Lake Okeechobee, the Lower Mississippi River and the Texas Gulf Coast.
Roughly 22% of the nation’s drinking-water facilities rely on surface water that tests above this threshold. Experts note that spring applications followed by rain drive runoff into streams, and that atrazine presence usually signals broader pesticide contamination. While the EPA is conducting a registration review, it has signaled intent to reapprove the chemical, dismissing recent WHO International Agency for Research on Cancer findings that label it probably carcinogenic. The US Fish and Wildlife Service also concluded atrazine poses no extinction risk to threatened species.
Why it matters
Widespread atrazine contamination threatens drinking water safety and public health across the United States.
In this story
