Toughened ozone rule falls short of recommendation

By Deborah Zabarenko, Environment Correspondent

WASHINGTON (Reuters) - The Environmental Protection Agency toughened standards for ozone pollution on Wednesday, but these new requirements are more lax than the agency's own scientists recommended.

Stephen Johnson, the agency's chief, said he complied with the Clean Air Act and with scientific data in setting the new ozone standard at 75 parts per billion in ambient air in the United States. The previous standard was 80 parts per billion.

The EPA's Clean Air Scientific Advisory Committee recommended, however, a standard of 60 to 70 parts per billion, with the lower level suggested for children who are more vulnerable to ozone pollution, a prime component of smog.

Industries had urged the government to retain the higher standard, citing the high cost of meeting the new requirement.

"The regulation I signed today is compelled by the Clean Air Act and the most recent scientific data on the effects of ozone on human health," Johnson told reporters in a telephone briefing. "Since EPA last updated ozone standards ... scientific studies have indicated that ozone's health impacts are more significant and certain than we previously understood."

Unlike stratospheric ozone, which forms a protective layer high above Earth's surface, ground-level ozone can make it hard to breathe and aggravate asthma and other respiratory conditions. It also can damage plants, making disease and reduced crop yields more likely.

People most vulnerable to lung problems from ozone pollution include children and teens, the elderly, those with asthma and other lung ailments and those who work or exercise outdoors.

INDUSTRY AND ENVIRONMENTALISTS OBJECT