The Environmental Protection Agency (EPA) in the United States has tightened air quality standards in an effort to help improve public health.
The Environmental Protection Agency (EPA) in the United States has tightened air quality standards in an effort to help improve public health.
It is lowering the amount of smog-forming ozone permitted in the atmosphere for the first time in more than 10 years.
It is lowering the amount of smog-forming ozone permitted in the atmosphere for the first time in more than 10 years.
Health and environmental campaigners wanted more stringent limits but industry has lobbied against them.
Health and environmental campaigners wanted more stringent limits but industry has lobbied against them.
Industry leaders say complying with the new standards will prove expensive.
Industry leaders say complying with the new standards will prove expensive.
Ozone can harm people's lungs and exposure can aggravate conditions such as asthma and increase susceptibility to respiratory infections.
Ozone can harm people's lungs and exposure can aggravate conditions such as asthma and increase susceptibility to respiratory infections.
The new level is reduced from 80 parts per billion to 75 parts per billion.
The new level is reduced from 80 parts per billion to 75 parts per billion.
However, the EPA's clean air scientific advisory committee had unanimously recommended setting a standard no higher than 70 parts per billion.
However, the EPA's clean air scientific advisory committee had unanimously recommended setting a standard no higher than 70 parts per billion.
The committee had estimated that reducing smog to that level could prevent almost 4,000 premature deaths and about 7,000 hospital visits.
The committee had estimated that reducing smog to that level could prevent almost 4,000 premature deaths and about 7,000 hospital visits.
Cleaner air
Cleaner air
EPA Administrator Stephen L Johnson said the agency was meeting requirements of the Clean Air Act by signing "the most stringent" ozone standard ever.
EPA Administrator Stephen L Johnson said the agency was meeting requirements of the Clean Air Act by signing "the most stringent" ozone standard ever.
This decision by the EPA to lower the ozone standard unnecessarily will impose significant new burdens on states and others American Chemistry Council
This decision by the EPA to lower the ozone standard unnecessarily will impose significant new burdens on states and others American Chemistry Council
He said the act itself needed modernising and recommendations were being put to Congress.
He said the act itself needed modernising and recommendations were being put to Congress.
But, he added, the nation would still benefit from the new standard even if they were strict.
But, he added, the nation would still benefit from the new standard even if they were strict.
"America's air is cleaner today than it was a generation ago," he said.
"America's air is cleaner today than it was a generation ago," he said.
"By... strengthening the national standard for ozone, EPA is keeping our clean air progress moving forward."
"By... strengthening the national standard for ozone, EPA is keeping our clean air progress moving forward."
The EPA said the cost of implementing the standards would range from $7.6bn to $8.5bn (£3.7bn to £4.1bn) but that would be outweighed by health benefits valued up to $19bn (£9.3bn).
The EPA said the cost of implementing the standards would range from $7.6bn to $8.5bn (£3.7bn to £4.1bn) but that would be outweighed by health benefits valued up to $19bn (£9.3bn).
It said those benefits included preventing cases of bronchitis, aggravated asthma, hospital and emergency room visits, non-fatal heart attacks and premature death, among others.
It said those benefits included preventing cases of bronchitis, aggravated asthma, hospital and emergency room visits, non-fatal heart attacks and premature death, among others.
The BBC's Jonathan Beale says many scientists believe the new rules will not significantly reduce the dangers to public health caused by pollution.
The BBC's Jonathan Beale says many scientists believe the new rules will not significantly reduce the dangers to public health caused by pollution.
Industry fears
Industry fears
US-based campaigners Clean Air Watch say the reduction does not go far enough.
US-based campaigners Clean Air Watch say the reduction does not go far enough.
"Unfortunately, real science appears to have been tainted by political science," said Clean Air Watch president Frank O'Donnell.
"Unfortunately, real science appears to have been tainted by political science," said Clean Air Watch president Frank O'Donnell.
"The Bush Administration is compromising public health to save industry money."
"The Bush Administration is compromising public health to save industry money."
Many in industry disagree and fear additional expense to meet standards.
Many in industry disagree and fear additional expense to meet standards.
The American Chemistry Council (ACC) said in a statement that there was "no clear and substantial basis" for tightening the standards, AFP reports.
The American Chemistry Council (ACC) said in a statement that there was "no clear and substantial basis" for tightening the standards, AFP reports.
"This decision by the EPA to lower the ozone standard unnecessarily will impose significant new burdens on states and others even as they continue to try and comply with the 1997 standard," the ACC said.
"This decision by the EPA to lower the ozone standard unnecessarily will impose significant new burdens on states and others even as they continue to try and comply with the 1997 standard," the ACC said.
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