"The U.S. Supreme Court on Tuesday agreed to weigh a challenge by industry groups and some states to an Obama administration regulation intended to limit emissions of mercury and other hazardous pollutants mainly from coal-fired power plants."

"The Obama administration is expected to release on Wednesday a contentious and long-delayed environmental regulation to curb emissions of ozone, a smog-causing pollutant linked to asthma, heart disease and premature death."

"The Environmental Protection Agency on Monday rejected parts of a key Texas clean-air plan, setting up a conflict with deep implications both for the state’s electricity mix and air quality across much of the country."

"After failing to rid Beijing’s skies of pollution before a gathering of world leaders this week, Chinese officials took a different approach to smog control -- limit the data."

"COLUMBIA, SC — Hazardous chemical vapors are leaking through the top of an industrial waste dump along Lake Marion and are suspected of contaminating shallow groundwater near the surface of the 36-year-old site."

"Residents of parts of the Russian capital Moscow have been urged by the emergencies ministry to stay indoors because of a noxious gas that is spreading through the city."

"Potash Corp of Saskatchewan Inc agreed to spend more than $52 million on plant improvements and pay a $1.3 million civil penalty to resolve U.S. charges that it violated the Clean Air Act over the emission of harmful pollutants such as sulfur dioxide, U.S. authorities said."

"An ozone-destroying chemical long thought to be on the decline in Earth’s upper atmosphere is making an unexpected comeback, an international team of scientists has found."

"Antarctic hole in protective layer of gas stands around same level as 2010, 2012 and 2013, but scientists say recovery is on track"

"Federal appellate judges greenlighted yesterday U.S. EPA's implementation of a program to curb air pollution that drifts between states."