Low Levels of Caffeine Found In Waters of U.S. Pacific Northwest

In a new study, scientists document low levels of caffeine pollution in the waters off the Oregon coast, fresh evidence that contaminants from human waste are entering marine ecosystems with unknown risks to wildlife and human health. In a series of tests conducted at 14 coastal locations, researchers found that caffeine levels were higher — about 45 nanograms per liter — in remote waters, while levels were below reporting limits (about 9 nanograms per liter) near “potentially polluted” areas such as sewage treatment plants, the mouths of rivers, and larger communities, National Geographic reports. According to the findings, published in the journal Marine Pollution Bulletin, the higher levels are likely occurring near sites with on-site waste disposal systems that are subject to less monitoring than larger wastewater treatment plants. While the environmental effects of such low-level contamination are not known, experts say they are a reminder of the range of pollutants — from pharmaceuticals to artificial sweeteners — entering natural ecosystems through human waste.