This coffee addiction of ours might be getting out of hand.

A study out of Portland State University found that water just off the coast of Oregon is slightly caffeinated — even though that’s not its natural state. Scientists think the water is contaminated with caffeine because of sewage seeping out to the ocean and septic runoff.

They’re calling it caffeine pollution, and it comes from humans. The study, headed by graduate student Zoe Rodriguez del Rey, indicates that high rainfall and sewer overflows — sometimes in state parks — flush contaminants out into the ocean.

Caffeine levels were measured at 14 coastal locations in Oregon, some of which were near wastewater treatment plants, towns and streams emptying into the ocean.

From Portland State University:

The study found high caffeine levels near Carl Washburne State Park (Florence, Ore.) and Cape Lookout, two areas not near the potential pollution sources, yet low levels of caffeine near large population centers like Astoria/Warrenton and Coos Bay. High levels were also found following a late-season storm of wind and rain that triggered sewer overflows.

The primary source doesn’t seem to be waste-treatment plants as suspected.

So, is it Oregon’s fault? Looks like it, but that state isn’t the only offender by far. Other studies have noted caffeine in other bodies of water, including the North Sea, the Mediterranean Boston Harbor, Sarasota Bay in Florida and Puget Sound.

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