Ozone exposure could trigger heart attacksJune 26th, 2012 - 3:20 pm ICT by IANS
Washington, June 26 (IANS) Young, healthy adult volunteers exposed for two hours to ozone developed physiological changes tied to cardiovascular damage.
They showed evidence of vascular inflammation, a potential reduced ability to dissolve artery-blocking blood clots, and changes in the autonomic nervous system that controls the heart’s rhythm. The changes were temporary and reversible in these participants.
Pollutants from vehicles, power plants, industry, chemical solvents and consumer products create ground level ozone by reacting in the presence of sunlight. Recent studies have linked acute exposure to ozone and death but little is known about the underlying pathways responsible, the journal Circulation reports.
“This study provides a plausible explanation for the link between acute ozone exposure and death,” said Robert B. Devlin, senior scientist at the US Environmental Protection Agency’s (EPA) National Health and Environmental Effects Research Lab, who led the study, according to an EPA statement.
Devlin and colleagues focused on a single, short-term exposure and not the effects of years of exposure to ozone. They exposed a group of volunteers, aged between 19 and 33 years, to 0.3 parts per million (ppm) of ozone.
The dose was higher than the EPA’s eight hour ozone standard of 0.076 ppm. However, a person breathing 0.3 ppm for two hours receives roughly the same amount of ozone as does a person breathing the lower 0.076 ppm for eight hours, Devlin noted.
Study participants underwent two controlled exposures - one to clean air and one to ozone-polluted air - at least two weeks apart. During each exposure, participants alternated 15-minute periods of stationary cycling and rest.
None of the participants reported complaints or physical symptoms after inhaling clean air or ozone. However, immediately following and the morning after ozone inhalation, tests showed significant ozone-induced vascular changes compared to clear-air exposure.
The World Health Organization estimates two million people worldwide, mostly elderly people with cardiovascular disease, die because of acute exposure to air pollution. The EPA puts the yearly U.S. toll at 40,000-50,000 deaths.
“People can take steps to reduce their ozone exposure, but a lot of physicians don’t realize this,” Devlin said.
- Prenatal exposure to pollution harmful for kids - May 21, 2012
- Smog bad for your heart: Study - Jul 22, 2010
- Carbon monoxide increases health risk to elderly heart patients - Sep 01, 2009
- Spending even two hours in traffic can cause heart problems - Jan 23, 2010
- High pollution levels ups heart attack chances - Sep 21, 2011
- Polluted air 'ups obesity risk in young animals' - Dec 03, 2010
- Chronic inhalation of polluted air 'can lead to inflammation, heart risk' - Apr 17, 2011
- Even acceptable ozone exposure can adversely affect lung function - Jul 24, 2009
- Does air pollution erode mental sharpness? - Feb 14, 2012
- Tiny blood vessels in the eye show pollution-heart disease link - Dec 01, 2010
- How air pollution can aggravate heart problems - Mar 10, 2011
- Vitamin D levels linked with health of blood vessels - Apr 04, 2011
- Nitrogen dioxide exposure lowers in vitro fertilization success - Apr 13, 2010
- Pollution 'can cause obesity and diabetes' - Dec 28, 2010
- Air pollution takes a toll on blood vessels - Nov 18, 2009
Tags: acute exposure, adult volunteers, autonomic nervous system, chemical solvents, environmental protection agency, ground level ozone, heart attacks, journal circulation, minute periods, ozone exposure, parts per million ppm, physiological changes, plausible explanation, polluted air, power plants, study participants, term exposure, us environmental protection agency, vascular changes, vascular inflammation