It is known that environmental pollution deteriorates health conditions of city populations, so the cities are aiming to restrain traffic to a minimum. The research, in which the abovementioned institutions included 8.8 million of people, who during 2003 and 2010 lived in different parts of London, has shown that people in the areas with increased traffic have lower life expectancy and are also at increased risk of stroke.

The researchers compared the levels of traffic noise in different areas of the city, and also divided the time of day between 7h and 23h, and the night time. They divided the participants into two groups, the adults between 25 and 74 years of age, and the elderly over 75, and studied the data about deaths and hospitalisations.

They discovered that the areas where the noise level exceeded 66 decibels had 4 percent more deaths than areas with the noise level under 55 decibels. The most common cause of death were cardiac arrest and problems with blood circulation, which were caused by high blood pressure, trouble with sleeping and noise induced stress.