High ozone linked to respiratory deaths
A U.S. study suggests people who live in areas with elevated ground ozone levels have a 30 percent greater risk of death due to respiratory problems.
The research, published in the New England Journal of Medicine, said the issue is not just the effects of high-ozone days but the effects of long-term cumulative exposure, New York University Langone Medical Center said Thursday in a release.
Lead author Michael Jerrett of the University of California, Berkeley, said background levels of ozone have at least doubled since pre-industrial-revolution times.
The findings are based on American Cancer Society data that followed 450,000 people from 1982 to 2000.
Riverside, Calif. had the highest mean daily maximum ozone concentration during the 18-year period with 104 ppb. Los Angeles was a close second, with an estimated 43 percent increased risk, the report said.