A new smog standard that President Obama withdrew last fall would save thousands of lives throughout the nation each year, particularly in the Los Angeles region, New York City and Chicago, according to a new study led by Johns Hopkins University scientists.

Last September, Environmental Protection Administrator Lisa Jackson was about to announce a new ozone standard, expected to be set at 70 parts per billion, when Obama stepped in to stop it because of economic concerns.

The Johns Hopkins analysis determined that implementing the 70 ppb standard would avoid 4,130 deaths from heart attacks and respiratory diseases each year — 67 percent more saved lives than the existing standard, which is set at 75 ppb.

And a more stringent one, 60 ppb, would save nearly 8,000 lives per year, compared with 2,480 under the current standard, according to the study, which was published online on July 18 in the journal Environmental Health Perspectives. The EPA's scientific advisory panel had recommended a new standard between 60 and 70 ppb.

In addition, millions of cases of asthma attacks and other acute respiratory problems would be avoided yearly, as well as millions of days of missed school, according to the study.

The scientists said the tougher smog standards “would result in dramatic public health benefits.”

“We contend that a more stringent standard would prevent a substantial number of adverse health outcomes,” wrote the researchers, led by senior scientist Frank Curriero of the Johns Hopkins Bloomberg School of Public Health.

The team calculated the reduced deaths by incorporating data from a variety of health studies around the country that have found that whenever ozone levels rise, deaths from cardiovascular and respiratory problems rise, too.

Reducing ozone is costly, since it means new controls on car and truck exhaust, consumer products and industrial plants such as refineries.

EPA officials estimated that setting the 70 ppb standard would cost between $19 billion and $25 billion per year, including the estimated $8 billion for meeting the current standard set by the Bush administration in 2008. However, the agency estimated the health benefits would have been worth $11 billion to $37 billion per year.

The health benefits in the new study were tabulated only for the months of May through September, which is smog season for most of the country. Ozone is a photochemical reaction between nitrogen oxides and hydrocarbons, pollutants that come mostly from motor vehicles but also industrial plants and consumer products.

The four-county Los Angeles basin has the worst ozone levels in the country, followed by parts of California’s San Joaquin Valley. Other smoggy areas are Houston, Chicago and Phoenix.

Because of their large populations, the highest number of reduced deaths were calculated for Los Angeles, New York City and Chicago. But the scientists said large numbers of people would be saved in many other cities, including Philadelphia, Washington, D.C., Atlanta, Detroit, Phoenix, Boston and Dallas.

“There is a substantial geographic variation, with the highest estimated reductions occurring in Southern California, the mid-West and portions of the Northeast corridor,” the report says.

Many city leaders and business representatives argued that the new standards would be unreachable without severe costs to their economy. Some areas, particularly in California, already are struggling to meet the current standard.

The scientists said meeting the existing one nationwide would reduce deaths by nearly 2,500 per year. But if the EPA reduced the standard to 70 ppb, the avoided deaths would increase by 67 percent, and if it was set at 60 ppb, they would increase by 214 percent, the scientists wrote.

“Our results quantify the immediate health impacts of achieving ozone standards, instead of projecting benefits into the future. These results are of particular public health significance in light of the executive decision to withdraw proposed ozone [standard],” the study says.

In addition to Curriero, Neal Fann of the EPA’s Office of Air Quality Planning and Standards, Jesse Berman of Johns Hopkins and several researchers from the American Thoracic Society were co-authors of the report.

This story was first reported by Marla Cone and was reprinted with permission from Environmental Health News.