There are a few things more ubiquitous about the Pacific Northwest than rain and coffee. But now a new study suggests that this could be a deadly combination for the region's marine life, reports National Geographic.


Scientists have found that the coastal waters off the coast of Oregon and Washington are brimming with elevated levels of caffeine. Though it's still unclear exactly what effect this may have on local marine ecosystems, the findings raise concerns that human waste contaminants are entering the region's natural water systems. Of course, it doesn't help that the region is also known for its rain and large volume of runoff.


The study, which analyzed samples taken from up to 14 different locations along the Pacific Northwest coast, found caffeine levels as high as 44.7 nanograms per liter. Shockingly, many of the highest measurements came from some of the most remote and "pristine" sampling locations, showing a strong correlation with the occurrence of storms and other periods of high runoff.


Caffeine contamination is worrisome, but it's likely just the tip of the iceberg. If elevated caffeine levels are found in seawater, then other human waste contaminants are likely there too.


"Caffeine is pretty darn ubiquitous, and there is growing evidence that this and other understudied contaminants are out there," said hydrologist Dana Kolpin of the Toxic Substances Hydrology Program, part of the U.S. Geological Survey. "There is a whole universe of potential contaminants including pharmaceuticals, hormones, personal-care products like detergents or fragrances, even artificial sweeteners."


Oregon's coastal waters are also known for having one of the largest marine "dead zones" in North America, a phenomenon that is often triggered due to pollutants in runoff.


Few studies have been performed on the widespread effect that caffeine levels might have on marine wildlife, but some lab experiments done on intertidal Pacific Northwest mussels have shown that caffeine exposure causes them to produce specialized proteins in response to the environmental stress. And if caffeine has damaging effects at one level of the food chain, it's likely to have repercussions throughout it.


"With caffeine, we're not yet sure about its environmental effects," said Kolpin. "But it's a very nice tracer, even if it doesn't have a large effect, because in most parts of the world, you know that this is coming from a human waste source."


Interestingly, the Pacific Northwest isn't the first place found to have caffeine-laced seawater. Caffeine has also been discovered in the Mediterranean, the North Sea and even Boston Harbor (giving a whole new meaning to idea of a "Boston Tea Party!"). Though caffeine is currently unregulated in wastewater, these studies may soon offer grounds for that policy to change.


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Bryan Nelson ( @@brynelson ) writes about everything from environmental problems here on Earth to big questions in space.

Pacific Northwest coastal seas found to be highly caffeinated
Residents of the Pacific Northwest are known for their love of coffee, so much that their coastal seas are now frothy with caffeine.