It takes about nine hours of hard hiking to reach Monument Springs within Grand Canyon National Park.
But when scientists with the U.S. Geological Survey tested the water trickling from the canyon wall they found chemicals, known as PFAS, that originate in things like cookware and rain jackets.
They also found pharmaceuticals like ibuprofen.
“To be in such a remote location and to find those results was quite eye-opening,” says hydrologist Nick Paretti who co-authored a study on the findings.
They traced some of the chemicals to the national park’s water treatment plant, miles away and thousands of feet above the spring.
Hydrologist Kimberly Beisner says it shows there’s a complex system of “faults and fractures and places in the rock that the water would want to move through.”
“I think that is really fascinating and speaks to pathways that the water is taking in the subsurface of Grand Canyon,” Beisner says.
She says they’ve tested other springs in nearby drainages and also found forever chemicals, but they didn’t detect pharmaceuticals like they did in Monument Springs.
She says that raises more questions about how water flows between the rim and the river.
