"From California to the Great Lakes, persistent water pollution shows that no beach is an island when it comes to public health threats like hepatitis, dysentery and stomach flu."

"President Barack Obama's plan to curb climate change could transform American energy, potentially dealing a blow to the coal-fired power plants that supply much of the nation's electricity but also pump planet-warming gases into the atmosphere."

"HOUSTON -- A federal agency investigating a deadly explosion at a Texas fertilizer plant told a Senate committee Thursday that regulation of the dangerous chemicals used in the industry fall under a 'patchwork' of standards that are decades old and are far weaker than rules used by other countries."

"President Barack Obama has vowed to tackle climate change in his second term, but so far has not acted to strengthen a tool that does not require backing from Congress - the National Environmental Policy Act."

"Just a day before President Obama announced he would only approve the Keystone XL pipeline if it 'does not significantly exacerbate the climate problem,' six environmental groups quietly lodged a protest with the State Department charging it would do exactly that."

"Exxon Mobil Corp.'s bid to shield from public view its inspection results for a shuttered pipeline that leaked at least 5,000 barrels of heavy Canadian oil sands crude in Arkansas this spring is galvanizing a debate over transparency and spill readiness that could affect the future of Keystone XL."

In January 2013, representatives of some 140 nations met in Geneva to finish a treaty to minimize emissions of mercury. In the end, they gave an exemption to the use of a mercury compound, thimerosol, as a preservative in some children's vaccines.

"A potentially deadly heat wave is expected to bear down on some Arizona and California desert areas in the next few days, forecasters said on Wednesday."

"Every year, people add 30 billion tons of carbon dioxide to the air, mostly by burning fossil fuels. That's contributing to climate change. A few scientists have been dreaming about ways to pull some of that CO2 out of the air, but face stiff skepticism and major hurdles. This is the story of one scientist who's pressing ahead."

"[Tuesday's] Supreme Court decision significantly expanding the rights of property owners to challenge the terms of land-use permits has puzzled environmental law experts and has liberal groups accusing the conservative justices of judicial activism."