by Doyin Jaiyesimi

On a typical day in Lagos, commuters have to brace themselves for episodes of insane driving, fits on anger, outbursts of curses and of course, the incessant blaring of car horns. A new study has revealed that people exposed to traffic noise stand a high risk of having hypertension or stroke. 

It is a worrying discovery for those who live close to highways or areas prone to heavy traffic, typical of a densely populated city like Lagos.

Researchers in the study published in PLoS ONE journal have found that for every 10-decibel increase in traffic noise, there is a 12 per cent higher risk of heart attack. In case you are wondering just how loud 10 decibels really is, 10 decibels is about as loud as the rustling of leaves while a residential area (like the wealthy enclaves of Abuja or Lagos) with no traffic is 40 decibels loud. A commuter in a passenger car is  exposed to 90 decibels during heavy traffic. And you should be worried even if you have a driver and drive in an air-conditioned car: the study also suggests that traffic noise does not have to be deafening to affect your health.

The study by Mette Sorenson and her fellow researchers was carried out over a ten-year period, focusing on the lives of more than 50,000 men and women living in two of Denmark’s largest cities, Copenhagen and Aarhus. The researchers monitored each participants’ health over the course of the study. For the 1,600 people who had the first heart attack, it was found that the louder the traffic noise near their homes was, the greater the risk they faced. Dr Robert Bonow, a professor of Medicine at the Northwestern Feinberg School of Medicine, explained that a variety of things could account for the link between traffic noise and heart attacks; one of which is stress.

“People who live in hectic urban centers tend to have more stress than those in quieter locales, and stress is a well-known trigger of heart attack. The noise itself probably does increase stress and the levels of stress hormones like adrenaline”, he says. This link is also in line with findings from other previous studies. A report published last year in BMJ.com established that being exposed to high levels of traffic pollution may boost the risk of a heart attack. The risk was however found to be transient, lasting between come to six hours.

So what does this mean for those who cannot avoid being exposed to traffic noise? Well, the researchers have recommended that people who live near traffic prone areas should sleep in a quieter interior room. Try and reduce the noise coming into your house as much as possible. For those who cannot avoid the noise, we wait for the day something will be done about the traffic situation in the nation.