Pollution
Low oxygen areas are disappearing almost a month earlier than they did 30 years ago.
Nationwide study shows how manufacturing facilities can increase levels of medical compounds in waterways.
Researchers found that efforts to curtail tourism-related emissions have been outpaced by the industry's growth.
Ambitious plan aims to keep waste out of rivers without massive new pipes.
Scientists are developing a "living sensor" that eats hydrocarbons to monitor the country's extensive network of petroleum pipelines.
Scientists discuss the risks and feasibility of using solar geoengineering to cool us off.
Fish expend energy metabolizing drugs and personal products in fresh water.
Green plant could help clean up heavy metal contamination at industrial sites.
The solution flowing through the Keystone pipeline isn't just crude oil. Scientists are now learning what that means for spills.
Nitrogen isotopes show how nutrients leach out of septic tanks and into pond ecosystems.
People who eat fish from glacial meltwater may be at risk from persistent organic pollutants produced in the 20th century.
Sediment core from a Copenhagen lake tells the story of the Industrial Revolution.