World Health Organisation establishes maximum guideline levels for 5 noise sources—including road traffic—to protect human health
Noise is one of the top environmental risks to health and well-being in Europe. This is confirmed by the Environmental Noise Guidelines for the European Region just published by the World Health Organisation (WHO). The new guidelines were drafted with the collaboration of researchers from the Barcelona Institute for Global Health (ISGlobal), a centre supported by the ”la Caixa” Banking Foundation.
The guidelines identify the noise levels with significant health effects and recommend interventions to reduce exposure. For the first time, the guidelines recommend specific values for five different types of noise source: three types of transportation (road traffic, railway and aircraft), wind turbines and leisure activities.
For each of these five noise sources, the guidelines make specific recommendations on annual average noise levels over the day, evening and night (24 hours, Lden indicator) and average night-time exposure (Lnight indicator). In the case of road traffic—the most common source of noise pollution—the WHO recommends reducing the average 24-hour noise levels (day, evening, night level) to below 53 dB Lden because exposure above this level is associated with adverse health effects. The guideline level for night-time exposure is 45 dB Lnight. The lowest levels recommended were for aircraft: 45 dB Lden for the 24-hour average and 40 dB Lnight for the night-time value. Previous WHO guidelines defined generic recommendations on daytime and night-time levels. They were not source specific and no guideline values for averaged 24-hour exposure were given. The earlier guidelines recommended maximum levels of 55 dB Lday and 40 dB Lnight for the day and night, respectively. The European Union, on the other hand, recommends a maximum level of 55 dB Lden for the 24-hour period and 50 dB Lnight for the night-time period.
The new recommendations are based on data from systematic reviews of the currently available scientific evidence. They were developed by 18 international experts, 4 of whom are members of the ISGlobal team: Maribel Casas and Maria Foraster analysed the relationship between noise and cardiovascular and metabolic diseases; Payam Dadvand and Mark Nieuwenhuijsen studied the link with pregnancy-related complications.
The health outcomes associated with noise exposure that were considered critical for developing the recommendations were cardiovascular disease, sleep disturbance, annoyance, cognitive impairment, hearing impairment and tinnitus. The authors also analysed the relationship between noise and problems during pregnancy (preterm birth and low birth weight), quality of life and mental health, diabetes, and obesity, although less scientific evidence is currently available on these outcomes.
ISGlobal researcher Maria Foraster highlights that the new guidelines “have concluded, after rigorous evaluation, that noise is an important environmental risk factor for health” and that they “provide more evidence on the cardiovascular and metabolic effects of environmental noise, among other effects “and also “that they use the same indicators as the European Union, thereby making it easier to predict the long-term health effects of noise pollution and develop effective action plans.” Foraster concludes, “We strongly urge European policy makers to develop and implement legislation on the basis of the recommendations in these guidelines to benefit the health of the whole population.”