"A Senate resolution seeking to reverse federal regulations limiting emissions of mercury and other toxic substances from coal-burning power plants failed to win passage on Wednesday. The resolution, introduced by Senator James M. Inhofe, an Oklahoma Republican, won support from 46 senators; 53 voted against it."

"The Obama administration proposed stricter standards to control harmful soot from heavy industry on Friday, a move expected to save lives but which drew criticism from Republicans and industry worried the costs of compliance will hurt the economy."

"Risking an election-year backlash from Republicans, the Obama administration is proposing new air quality standards to lower the amount of soot that can be released into the air.

The move, to be announced Friday, is likely to win support from environmental groups and public health advocates but exposes the president to potential criticism from congressional Republicans and industry officials that the rules are overly strict and could hurt economic growth and cause job losses in political swing states such as Ohio and Pennsylvania.

"Diesel engine fumes can cause lung cancer and belong in the same potentially deadly category as asbestos, arsenic and mustard gas, World Health Organisation (WHO) experts said on Tuesday."

"With the Obama administration facing a deadline this week to suggest any changes to the national air quality standards for soot, the pressure is building on all sides."

"RIO de JANEIRO -- The Rio+20 Secretary-General said today that the absence of such world leaders as U.S. President Barack Obama, German Chancellor Angela Merkel and UK Prime Minister David Cameron will not undermine the sustainable development summit later this month."

"The Environmental Protection Agency and American Lung Association said they’re close to settling a lawsuit filed by the advocacy group to force regulators to issue overdue rules on soot."

"A senior Chinese official demanded on Tuesday that foreign embassies stop issuing air pollution readings, saying it was against the law and diplomatic conventions, in pointed criticism of a closely watched U.S. embassy index."

"Three conservation organizations today filed legal action challenging the U.S. Environmental Protection Agency's failure to update air quality standards for acid rain."

"SEQUOIA NATIONAL PARK, Calif. -- The California forest that is home to the biggest and oldest living things on earth, the giant Sequoia redwoods, also suffers a dubious distinction. It has the worst air pollution of any national park in the U.S."

"For years, U.S. government agencies have told the public, veterans and Congress that they couldn't draw any connections between the so-called 'burn pits' disposing of trash at the military's biggest bases and veterans' respiratory or cardiopulmonary problems. But a 2011 Army memo obtained by Danger Room flat-out stated that the burn pit at one of Afghanistan's largest bases poses 'long-term adverse health conditions' to troops breathing the air there."

"BP will spend more than $400 million to significantly reduce noxious air pollution from its massive refinery in northwest Indiana, the company announced today in a settlement with federal authorities and environmental groups that could set a precedent for oil companies nationwide."

"Kathy Omachi was eating at McDonald's in Reedley [Calif.] recently, and she counted 51 gravel trucks pass by -- all in the time she finished a hamburger and fruit smoothie. The lifelong resident of this farming town, which is southeast of Fresno and within a few miles of three rock quarries, fears that even more trucks, with their dirty exhaust, will be on the road if nearby mining is expanded."

"AUSTIN, Texas -- A Texas District Court judge Monday issued a letter announcing that he intends to rule against the state environmental agency's air permit for a proposed power plant in Corpus Christi."

"In what the White House calls a milestone in its effort to cut red tape, the Obama administration today said it was overhauling or eliminating five regulations -- including a Clinton-era air-pollution rule -- in an effort to save $6 billion in unnecessary costs over the next five years."