[Home]   [Full version]  

Ozone key to link between heat and increased cardiovascular death risk

Nov 26 ,Medicine & Health


Ozone may prove the key to the link between high temperature and the increased risk of death from heart disease or stroke, suggests research published ahead of print in Occupational and Environmental Medicine.

The researchers base their findings on a population of almost 100 million people in 95 different geographical areas across the USA during the summer months of June to September.

Participants were already taking part in the National Mortality and Air Pollution Study (NMMAPS), which looked at health and weather pollution between 1987 and 2000.

During this period, 4 million heart attacks or strokes occurred, and when the authors plotted daily deaths against fluctuations in temperature during one day, they found that ozone was a common link.

The results showed that the higher the ozone level, the higher was the risk of cardiovascular death attributable to high temperatures.

Ozone levels ranged from a daily average of 36.74 parts per billion to 142.85 ppb, while average daily temperatures ranged from 20 to around 42 degrees Centigrade.

A 10 degree temperature increase on the same day was associated with a rise in heart disease or stroke deaths of just over 1% at the lowest ozone level and by more than 8% for the highest levels.

Ozone is chemical pollutant that is strongly tied to weather conditions, particularly the amount of ultraviolet light in the atmosphere, say the authors. It is generated by a reaction between nitrogen oxides, volatile organic compounds, and oxygen in sunlight.

A link between temperature and ozone in driving up cardiovascular mortality is plausible, say the authors.

Exposure to ozone may affect the airways and the autonomic nervous system, so making people more susceptible to the effects of fluctuations in temperature, they suggest.

Public health warnings during hot weather ought to include information on ozone levels, when these are high, they say.

Rising temperatures and the impact of ozone are likely to become increasingly important as the world heats up as a result of global warming, they add.

Source: British Medical Journal

Related stories:

Increased carbon dioxide in atmosphere linked to decreased soil organic matter
A recent study at the University of Illinois created a bit of a mystery for soil scientist Michelle Wander – increased carbon dioxide in the atmosphere was expected to increase plant growth, increase plant biomass and ultimately beef up the organic matter in the soil -- but it didn’t. What researchers found instead was that organic matter decay increased along with residue inputs when carbon dioxide levels were increased and they think the accelerated decay was due to increased moisture in the soil.
2007 ozone hole 'smaller than usual'
The ozone hole over Antarctica has shrunk 30 percent as compared to last year's record size. According to measurements made by ESA’s Envisat satellite, this year’s ozone loss peaked at 27.7 million tonnes, compared to the 2006 record ozone loss of 40 million tonnes.
System to pinpoint airline passengers who contaminate cabins
Researchers developing a system that uses mathematical models and sensors to locate passengers releasing hazardous materials or pathogens inside airline cabins have shown that the technique can track a substance to an area the size of a single seat.
Europe’s new MetOp weather satellite reaches polar orbit
For 28 years, Europe has been operating its famous Meteosat weather satellites in geostationary orbit. Today, they were joined by the first of a brand new generation of meteorological satellites. MetOp is designed to provide a closer view of the atmosphere from low earth orbit, delivering data that will improve global weather prediction and enhance our understanding of climate change.
MetOp launch campaign resumed
With the launch of MetOp now set for 7 October at 18:28 CEST, the MetOp satellite is out of storage and preparations for launch are well underway at the Baikonur Cosmodrome in Kazakhstan.
Scientists find chlorine may contribute to ozone formation
Standard methods of predicting air pollution don’t take atmospheric chlorine into account, but the chemical could be responsible for 10 percent or more of daily ozone production in local air, research at UC Irvine has found.
Resisting Radiation
In Star Wars and Star Trek movies, people travel between planets and galaxies with ease. But our future in space is far from assured. Issues of hyperdrive and wormholes aside, it doesn't seem possible that the human body could withstand extended exposure to the harsh radiation of outer space.
Probing Question: Does commercial jet traffic affect climate?
It's hard to dispute that car and truck emissions affect the environment. Tail pipes cough out a brew of gases that contribute to smog, ground-level ozone and global warming. But what about jet pollution?

News discussion:

Medicine & Health news

[Home]   [Full version]