Noise

Context

Environmental noise can be defined as unwanted or harmful outdoor sound. It is a product of transport and industrial activity on land, in the air, on waterways, and on oceans. It is a pervasive pollutant that directly affects the health and well-being of exposed humans and wildlife. Tackling noise pollution is challenging — its harmful impacts are clear, yet it occurs as a direct consequence of society's demands for increased mobility and productivity.

Populations exposed to high noise levels can exhibit stress reactions, sleep-stage changes, and clinical symptoms like hypertension and cardiovascular diseases. All of these impacts can contribute to premature mortality. The World Health Organization (WHO) reports an onset of adverse health effects in humans exposed to noise levels at night above 40 decibels (dB).^[1]

There is also increasing scientific evidence regarding the harmful effects of noise on wildlife.^[2] Whether in the terrestrial or marine environment, many species rely on acoustic communication for important aspects of life, such as finding food or locating a mate. Anthropogenic noise sources can potentially interfere with these functions and thus adversely affect species richness, population size, and population distribution. In some instances, noise can be a cause of death, particularly in marine fauna. Underwater sound can travel great distances underwater, and its impacts may be felt far from the source of origin.

The Environmental Noise Directive (END),^[3] is the main European Union (EU) legal instrument through which land-based noise emissions are monitored and actions developed. It places an obligation on EU Member States to use common criteria for noise mapping (see Box 1). The END also obliges countries to develop and implement action plans to reduce exposure in large cities and places close to major transport infrastructure.

The END also requires Member States to select and preserve areas of good acoustic environmental quality, referred to as 'quiet areas'. The EEA has recently published guidance on protecting such areas. The EEA has also published guidance to assist countries on how to consider the latest health-impact evidence in developing their action plans.

Key trends

The Noise Observation and Information Service for Europe (NOISE) displays noise-mapping data reported by countries under the END to the EEA. Data are available at European and national scale for most EEA member countries, including 472 urban agglomerations. Countries do not always report complete datasets — information varies depending both upon the type of source concerned and the year of reporting (2007 or 2012). Overall, information is significantly less complete for the 2012 data, preventing any robust exposure or trend analysis.

Figure 1 shows exposure to environmental noise in Europe for 2011. Road traffic noise clearly contributes to the greatest level of exposure within the European population, with at least 125 million people being exposed to levels above the END threshold of 55 dB L_den.

Figure 1: Exposure to environmental noise in Europe within* and outside urban agglomerations, 2011

In addition, many people were also exposed to rail, aircraft, and industrial noise, particularly in towns and cities. Similarly, night-time road traffic is another major source of noise exposure, with over 83 million Europeans exposed to harmful levels of noise greater than 50 dB Lnight.^[5]

The average exposure to noise (i.e. Lden above 55 dB and Lnight above 50 dB) in selected urban agglomerations remained broadly constant between 2006 and 2011, according to comparable data reported by countries for these two years.

In urban environments it is evident from Figure 2 that a high percentage of the population in selected capital cities in Europe are exposed to detrimental levels of road-traffic noise according to data reported by countries. Exposure to the WHO interim target level of 55 dB L_night is also indicated in Figure 2.

Figure 2: Population exposed to night time noise from road traffic above 50dB in selected capital cities, 2011

Recent estimates of exposure to environmental noise indicate that it contributed to at least 900 000 additional prevalent cases of hypertension in 2011, 43 000 additional cases of hospital admissions and to 10 000 cases of premature mortality each year. These numbers are likely to be significantly underestimated, potentially by more than a factor of two, due to the lack of complete data reported by countries. Almost 90% of the health impact caused by noise exposure is associated with road traffic noise.^[5] In terms of economic impact, noise from road and rail traffic is estimated to cost the EU EUR 40 billion per year.^[6]

When the END requires a country to implement an action plan to reduce exposure to noise there are several measures a country can take. Examples of effective measures presently being undertaken in EEA member countries to reduce noise exposure include local measures such as the installation of road or rail-noise barriers, or optimising aircraft movements around airports. However, it is widely acknowledged that the most effective actions to reduce exposure tend to be those that reduce noise at source, e.g. by managing the numbers of road vehicles, or their noise emissions by e.g. introducing quieter road tyres.

Prospects

In the short term, the European Commission is expected to undertake a review of the implementation of the END by 2016. Beyond this, the 7th Environment Action Programme (7th EAP)^[7] 'living well, within the limits of our planet', aims to ensure that by 2020 noise pollution in the EU has significantly decreased, moving closer to WHO-recommended levels.

There is a clear need to improve the Member States' implementation of the END, in particular with respect to the completeness, comparability and timeliness of reporting. The lack of complete datasets reported under the END may mean there will be a major challenge in the future to robustly evaluate whether the 7th EAP objective of significantly reducing noise pollution by 2020 has been met. Furthermore, it will still be difficult to determine exactly how close Europe has moved toward meeting the WHO NNG for Europe (a level of 40 dB) in the future, as reporting of this information remains voluntary for countries. 

To achieve the targets for reducing noise, the 7th EAP proposes to implement an updated noise policy, aligned with the latest scientific knowledge, as well as measures to reduce noise at source and improvements in city design.