Stay Connected

NOAA Research News

NOAA-funded researchers find caffeine in Pacific Northwest coastal waters
SuperUser Account

NOAA-funded researchers find caffeine in Pacific Northwest coastal waters

Contact: David Santen/Portland State University, 503-725-8765, or John Ewald/NOAA, 240-429-6127 

Finding caffeine in waters just off a coastline heavy with coffee shops may not be surprising. What a new NOAA-funded study does reveal is that traces of caffeine in Pacific Northwest waters point to a likely source of the stimulant: septic tanks and sewer overflows.


Results of the study, funded in part by Oregon Sea Grant and NOAA, were published in the July 2012 Marine Pollution Bulletin. The study was conducted by scientists at Portland State University and Washington State University, Vancouver.

This research, the first to look at caffeine contamination off the Oregon coast, found elevated levels of caffeine at several sites in Pacific Ocean waters off the coast of Oregon—though not necessarily where researchers expected.

Starting in spring 2010, scientists collected and analyzed samples from 14 Oregon coastal locations and seven adjacent water bodies as far north as Astoria and as far south as Brookings. Researchers identified locations as potentially polluted if they were near wastewater treatment plants, large population centers, and rivers and streams emptying into the ocean.

The study found high caffeine levels near Carl Washburne State Park in Florence, and at Cape Lookout – two areas not near the potential pollution sources. Meanwhile, the researchers also measured low levels of caffeine near large population centers like Astoria/Warrenton and Coos Bay. They also found that caffeine levels spiked following a late-season storm of wind and rain that triggered sewer overflows.

The results suggest that wastewater treatment plants are effective at removing caffeine, but that high rainfall and combined sewer overflows flush the contaminants out to sea. The results also suggest that septic tanks, such as those used at the state parks, may be less effective at containing pollution.

"Our study findings indicate that, contrary to our prediction, the waste water treatment plants are not a major source of caffeine to coastal waters," said Elise Granek, assistant professor of environmental science and management at Portland State University. "However, onsite waste disposal systems may be a big contributor of contaminants to Oregon’s coastal ocean and need to be better studied to fully understand their contribution to pollution of ocean waters."

Caffeine is found in many food and beverage products as well as some pharmaceuticals, and caffeine in waterways is directly related to human activity. Although many plant species produce caffeine, there are no natural sources of the substance in the Pacific Northwest. The presence of caffeine in ocean water may also signal additional pollution such as pesticides and pharmaceuticals, Granek said.

The NOAA National Sea Grant College Program is a network of 33 university-based programs located in every coastal and Great Lakes state. Each university program conducts scientific research, education, training, and extension projects designed to foster science-based decisions about the use and conservation of coastal resources.

NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter and our other social media channels.


See also:

Portland State University news release


Previous Article NOAA, partners: Earth’s oceans and ecosystems still absorbing about half the greenhouse gases emitted by people
Next Article NOAA, partners find 50-year decline in some Los Angeles vehicle-related pollutants



Phone: 301-713-2458
Address: 1315 East-West Highway Silver Spring, MD 20910

Stay Connected


Oceanic and Atmospheric Research (OAR) - or "NOAA Research" - provides the research foundation for understanding the complex systems that support our planet. Working in partnership with other organizational units of the NOAA, a bureau of the Department of Commerce, NOAA Research enables better forecasts, earlier warnings for natural disasters, and a greater understanding of the Earth. Our role is to provide unbiased science to better manage the environment, nationally, and globally.


Can't Find What You Need?
Send Feedback
Copyright 2018 by NOAA Terms Of Use Privacy Statement
Back To Top