Health impact assessment of traffic noise in Madrid (Spain)

Abstract

The relationship between environmental noise and health has been examined in depth. In view of the sheer number of persons exposed, attention should be focused on road traffic noise. The city of Madrid (Spain) is a densely populated metropolitan area in which 80% of all environmental noise exposure is attributed to traffic. The aim of this study was to quantify avoidable deaths resulting from reducing the impact of equivalent diurnal noise levels (LeqD) on daily cardiovascular and respiratory mortality among people aged ≥65 years in Madrid. A health impact assessment of (average 24h) LeqD and PM2.5 levels was conducted by using previously reported risk estimates of mortality rates for the period 2003–2005: For cardiovascular causes: LeqD 1.048 (1.005, 1.092) and PM2.5 1.041(1.020, 1.062) and for respiratory causes: LeqD 1.060 (1.000, 1.123) and PM2.5 1.030 (1.000, 1.062). The association found between LeqD exposure and mortality for both causes suggests an important health effect. A reduction of 1dB(A) in LeqD implies an avoidable annual mortality of 284 (31, 523) cardiovascular- and 184 (0, 190) respiratory-related deaths in the study population. The magnitude of the health impact is similar to reducing average PM2.5 levels by 10µg/m3. Regardless of air pollution, exposure to traffic noise should be considered an important environmental factor having a significant impact on health.