Ozone may prove the key to the link between high temperature and the increased risk of death from heart disease. Scientists base their findings on a population of almost 100 million people in 95 different geographical areas during the summer months.
During this period, 4 million heart attacks occurred. When the scientist plotted daily deaths against fluctuations in temperature during one day, they found that ozone was a common link, that show 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 and temperatures ranged from 20 to 42 degrees Centigrade.
A 10 degree temperature increase on the same day was associated with a rise in heart disease of just over 1 percent at the lowest ozone level and by more than 8 percent for the highest ozone levels.
Ozone is chemical pollutant that is strongly tied to weather conditions. 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.
Exposure to ozone may make people more susceptible to the effects of fluctuations in temperature.
Rising temperatures and the impact of ozone are likely to become increasingly important as the world heats up as a result of global warming.