ERC-funded research is uncovering unknown health hazards of noise. Mette Sørensen, senior researcher in the Department of Environment and Cancer at the Danish Cancer Society, says scientists have not been thorough in investigating the effect of traffic noise on other types of diseases.
By Florin Zubascu
Air pollution caused by traffic is well-recognised as a source of ill health and Europe’s smart cities are constantly monitoring and seeking to reduce it.
The same cannot be said for the second major form of pollution caused by traffic – noise. Beyond the fact that it causes annoyance and has been shown to induce stress, there has been little study of the health impacts of noise.
An ERC-funded study in Denmark is aiming to fill the gap, providing an evidence base for policies that will address this blight.
A total of 30 per cent of the European Union’s population lives in areas where noise levels exceed the 55 decibel sound limit recommended by the World Health Organisation. This has a negative impact on our health, as research shows traffic noise increases stress levels and fosters sleep deprivation, increasing the risk of cardiovascular disease.
But, says Mette Sørensen, senior researcher in the Department of Environment and Cancer at the Danish Cancer Society, scientists have not been thorough in investigating the effect of traffic noise on other types of diseases. “There is limited knowledge of the harmful effects of traffic noise,” she says. Apart from cardiovascular diseases the role of noise in other diseases has been, “virtually unexplored.”
Sørensen aims to change that. She has been awarded a €1.3 million five-year starting grant from the ERC to establish her own research group focusing on the health consequences of traffic noise, including effects on fertility, birth weight, cognitive performance, infections, cancer, cancer survival, health-related quality of life and health behaviour.
Sørensen is using SOUND PLAN, a computer model that maps the entire Danish road system and estimates noise levels across the country, which are then cross-referenced with health and lifestyle information from a cohort of 57,053 elderly people and 101,042 children.
The model takes into account the number of vehicles passing through residential areas and the number of lanes of traffic on each road. Cargo traffic routes are also accounted for, as the system is also able to differentiate between light and heavy traffic.
“Noise acts as a stressor and disturbs our sleep. It is the sleep deprivation that is harmful to our health,” says Sørensen. Her preliminary results show that 5 per cent of new diabetes and stroke cases, and four per cent of heart attacks in Denmark are associated with traffic noise.
In addition high traffic noise levels are taking a toll on the health of new-borns and children. “Outcomes in children include low birth weight and cognitive performance,” says Sørensen.
Urban areas, which are significantly noisier than rural areas, are home to 54 per cent of the world’s population.
Sørensen’s stark evidence of the health impact of the noise to which so many people are subjected should prompt policies to turn down the decibel level.
Sørensen herself is not keen on making policy prescriptions based on the results of her research. However, the EU has launched initiatives in this area and in 2011 the European Environment Agency recognised the Dutch province of Gelderland for its success in cutting traffic noise by reducing the number of traffic lanes, sinking local roads and building small sound barriers.
Road building materials are perhaps the most promising solution to this problem. A study commissioned by the Austrian government showed that introducing synthetic rubber to the classic asphalt mixture can reduce traffic noise by up to 8.2 decibels.