It is the average daily amount of air pollution, and not variations in its hourly levels links to the risk of respiratory and cardiovascular problems! A study made in Japan reveals that ‘high hourly rates of particulate matter (in excess of 200 ug/m3) around two hours before death were associated with a more than doubling in the risk of death from a bleed into the brain.’
The research published ahead of print in Occupational and Environmental Medicine High suggests that hourly levels of air pollution, more than double the risk of one type of stroke.