Transportation Noise Effects on Physical and Mental Health and their Corresponding Mitigation Strategies in Europe

Abstract

Objective:

Transportation noise is a pervasive environmental pollutant that has significant implications for physical and mental health, particularly in urban areas. This scoping review summarizes the long-term health effects of transport noise from road, rail, and aircraft sources and evaluates available mitigation strategies in Europe.

Methods:

Using the Reporting Standards for Systematic Evidence Syntheses (ROSES), we identified 74 peer-reviewed articles from Scopus, Web of Science, and Google Scholar in order to assess health impacts of noise and the available strategies for mitigating them.

Results:

Most studies encompassed European regions via multicountry datasets. The findings support the well-known impacts of noise on human health, including cardiovascular disease, increased blood pressure, annoyance, sleep disturbance, and evidence of adverse mental performance and cognitive impairment outcomes related to noise. Vulnerable populations, such as children and the elderly, are disproportionately affected. Mitigation strategies are subdivided into categories of source, propagation, and exposure. Propagation strategies, such as acoustic barriers and vegetation belts report 8–12 A-weighted decibel (dB(A)) and 2.5–8.5 dB(A) reduction, while source reductions of traffic optimization (1–3.5 dB(A)) and calming (1–5 dB(A)) are lower. Mitigation strategies addressing physical effects primarily focus on source, propagation, and planning measures, whereas strategies targeting mental effects emphasize exposure reduction, such as soundproofing and improvements to the immediate environment through greenery.

Conclusions:

Gaps remain in understanding the cumulative effects of multimodal noise exposure, gender-specific responses, and the integration of objective health measures. The scoping review highlights the potential and urgent need for integrated, proactive noise mitigation strategies in spatial and urban planning.

KEY MESSAGES

• (1)Transportation noise in Europe is a significant public health risk with children, the elderly, and those with pre-existing conditions experiencing disproportionate health burdens from long-term noise exposure.
• (2)The scoping review synthesizes 74 studies using the Reporting Standards for Systematic Evidence Syntheses reporting standard, integrating health impacts and mitigation strategies within one analytical framework.
• (3)Noise mitigation strategies vary in effectiveness, with acoustic barriers and green infrastructure offering greater reductions than traffic management alone, highlighting the importance of integrated mitigation strategies.
• (4)Including proactive noise mitigation in spatial and urban planning is essential for reducing public health risks and addressing regulatory and research gaps.

INTRODUCTION

Noise Pollution, Human Health, and the European Regulatory Framework

The impact of noise pollution on human health has long been a cause for concern. The potential of noise pollution to impact public health in a manner comparable to that of infectious diseases has been recognized for over a century.[1] Noise is widely acknowledged as an environmental burden and a well-established health risk, particularly in urban areas where large populations are exposed to disruptive and unwanted sound.[2] The World Health Organization (WHO) defines noise pollution as unwanted or harmful sound that induces discomfort and adversely affects both physical and mental well-being. Key sources include vehicular traffic, railways, airports, construction sites, and industrial processes, as well as recreational activities.[3,4]

Noise pollution represents a major health problem in modern society, leading to multiple adverse health effects if not properly monitored and assessed, including sleep disorders, learning impairment, ischemic heart disease, and annoyance reactions.[5] The prevalence of environmental noise pollution has reached critical levels, particularly in densely populated regions. In Europe, exposure to high noise levels has been linked to widespread sleep disturbances, cardiovascular diseases, cognitive impairments, and premature mortality.[6] Transportation noise, particularly from road and rail traffic, is responsible for the loss of at least 1.6 million healthy life years in European cities annually, primarily due to sleep disruption and cardiovascular conditions.[3] Railway noise, largely caused by rolling noise, affects around 22 million people who are exposed to levels exceeding 55 dB(A) both day and night.[7]

Vulnerable populations, including children, the elderly, and those with pre-existing health conditions, are particularly at risk, highlighting the need for effective noise mitigation strategies.[8] Beyond its physiological effects, noise pollution acts as a psychosocial stressor, interfering with communication, concentration, relaxation, and sleep. Long-term exposure to transport noise has been linked to an increased risk of hypertension, ischemic heart disease, and stroke.[9,10] In urbanized areas, road traffic remains the dominant noise source. While noise barriers provide localized relief, high-density urban environments require alternative approaches, such as the strategic use of green infrastructure and sustainable urban planning.[3]

This scoping review provides an integrated synthesis of transport noise research by combining evidence on health effects and mitigation strategies within a unified analytical framework. In contrast to earlier reviews that examined these domains separately, the present study combines them with the Reporting Standards for Systematic Evidence Syntheses (ROSES) framework. The study’s novelty is its bridging of environmental health outcomes and urban policy approaches to support evidence-based noise management.

Urban soundscapes are shaped by overlapping noise sources, with transportation infrastructure playing a critical role in acoustic environments.[11] The density and layout of roads and railway lines strongly influence noise distribution; higher road density and more uneven transport networks correlate with increased noise complaints. Primary roads located near residential areas contribute significantly to urban noise pollution. In contrast, motorways, which are typically situated further from residential zones, have less direct impact.[12] Similarly, railway infrastructure and variations in road network density exacerbate noise issues, underscoring the critical role of transport planning in shaping urban acoustic environments and quality of life.[12,13]

Over the past two decades, the European Union (EU) has strengthened its regulatory framework in order to address the issue of noise pollution. Key policies include the Fifth Environment Action Programme (1993) and the Environmental Noise Directive (END) of 2002, which aims to mitigate the health impacts of noise. The WHO recommends reducing night-time sound to levels to below 40 dB(A)–a target that has yet to be achieved across the EU.[3]

To comply with the END, EU countries must produce noise action plans (NAPs) every five years. These plans must include reviews of noise-related health outcomes, strategic noise maps, identification of populations exposed to noise at the community level and mitigation strategies for noise hot spots. Despite noise action planning being in its fourth round in the EU, millions of EU residents still face high noise levels. To understand the current state of transport-related noise exposure and mitigation in the context of the END, this study focuses on European research and the potential mitigation strategies that have been implemented. Several other counties have noise pollution or control standards such as the US EPA Noise Control Act of 1972, Japan’s Noise Regulation Law (1968) and subsequent Environmental Quality Standards (EQS) for Noise, or China’s more recent Law on Noise Pollution Prevention and Control, which came into effect in 2022. However, the European END differs from these three examples in that it requires extensive, cyclical, community-based strategic noise mapping to achieve total area coverage. The END has been widely implemented across a heterogeneous mix of countries and includes the unified application of the Common Noise Assessment Methods in Europe (CNOSSOS-EU) framework for noise modeling and mapping. Therefore, it is justified for our focus to be on the array of strategies applied within a common context rather than on comparing noise-related health outcomes and mitigation strategies across legal frameworks.

Study Objectives

The study employs a scoping review method to examine the long-term effects of noise exposure in urban European environments on mental health, and the range of noise mitigation strategies used to reduce these effects. The study is guided by three overarching questions:

• (1)What are the impacts of noise exposure in urban environments on mental and physical health?
• (2)What noise mitigation strategies are most typically implemented in the EU and how well do they attenuate sound and thereby influence health outcomes?
• (3)What areas require further research to better understand the relationship between noise-exposed populations and health outcomes?

MATERIALS AND METHODS

Scoping Literature Review

To ensure methodological transparency, reproducibility, and comprehensive evidence synthesis, a scoping review was conducted in accordance with the ROSES reporting standards.[14] The ROSES framework informed the development of the search strategy, eligibility criteria, screening procedure, and synthesis structure. The aim of this scoping review was to map the scope of the existing literature on transportation noise exposure, noise-related health outcomes, and mitigation strategies in Europe, classify types of available evidence, and identify key research gaps. The scoping review procedure consisted of four main stages:

• (a)Identification—searching Scopus, Web of Science, and Google Scholar using Boolean keyword combinations related to “transportation noise,” “public health,” and “urban environments.”
• (b)Screening—removing duplicate and irrelevant records based on titles and abstracts.
• (c)Eligibility—assessing full-text articles against predefined inclusion and exclusion criteria.
• (d)Inclusion—synthesizing studies that met all methodological and thematic requirements.

Table 1 shows the predefined inclusion and exclusion criteria for this study. These criteria are used to ensure methodological consistency, relevance, and alignment with the analysis objectives. The publication period was limited to 2002–2025, corresponding with the implementation of the EU END that established harmonized standards for noise assessment and management across Europe. Studies published before 2002 were excluded to avoid inconsistencies arising from outdated regulatory or methodological contexts. Only English-language publications were included to ensure accurate interpretation and consistent use of technical and health-related terminology. The geographical scope was restricted to European countries, as they operate under comparable noise management frameworks; therefore, studies conducted outside Europe were excluded. In terms of noise sources, the scoping review focused exclusively on road, rail, and aircraft noise, as these are the main transport-related contributors to urban environmental noise. Studies dealing with industrial, recreational, or occupational noise were excluded in order to maintain a clear focus on transportation systems that are relevant to spatial and urban planning and public health. Eligible studies had to examine the physical or mental health outcomes associated with noise exposure, such as sleep disturbance, annoyance, and cardiovascular effects. Studies focusing exclusively on economic, engineering, or nonhealth outcomes were excluded to preserve the review’s emphasis on health impacts. Only peer-reviewed journal articles and systematic reviews were included to ensure the methodological rigor and the reliability of findings. Conference abstracts and grey literature were excluded due to the limited detail they provide and the fact that they are not always subject to formal peer review. Finally, included studies had to evaluate mitigation strategies such as noise barriers, vegetation buffers, and urban planning interventions. To support the aim of examining both noise impacts and the effectiveness of corresponding mitigation measures, studies without a mitigation component were excluded.

Table 1.

Inclusion and Exclusion Criteria (Author’s Original Work)

Criteria	Inclusion	Exclusion	Justification
Publication period	2002–2025	Before 2002	Aligns with the introduction of the EU Environmental Noise Directive.
Language	English	Non-English publications	Ensures consistency and accurate interpretation.
Geographical scope	European countries	Non-European studies	Focuses on regions governed by comparable noise management frameworks.
Noise sources	Road, rail, and aircraft noise	Industrial, recreational, or occupational noise	Concentrates on transportation noise relevant to urban planning.
Health outcomes	Physical and mental health effects (e.g., sleep, annoyance, cardiovascular)	Nonhealth outcomes (e.g., economic or engineering focus only)	Ensures focus on health-related impacts.
Study type	Peer-reviewed journal articles and systematic reviews	Conference abstracts, grey literature	Ensures methodological rigor and data reliability.
Mitigation strategies	Studies examining noise barriers, vegetation buffers, urban planning interventions	Studies without mitigation focus	Supports dual focus on noise impacts and reduction measures.

Record Identification and Screening

The scoping review was conducted in accordance with the ROSES reporting standards, drawing on three major bibliographic databases encompassing a wide thematical range: Web of Science, Scopus, and Google Scholar. We employed a keyword search strategy using a combination of keywords related to noise, transportation, health outcomes, and mitigation, using Boolean operators.

In Web of Science, the search was performed using the search string {((noise AND (transport OR rail)) AND ((health OR well* OR mental OR annoyance) AND mitigation AND urban NOT climate*}, which yielded 242 initial records. After screening for relevance and removing duplicates, 48 articles were retained for full-text review. In Scopus, a structured search was applied to titles, abstracts, and keywords using the search string {(noise AND (transport OR rail) AND (well-being OR mental health OR annoyance)) AND planning}, applying filters for publication year (2002–2025), document type (article), language (English), open-access availability and country affiliation to EU countries. This resulted in 147 records, of which 47 were retained after screening. A complementary search was conducted in Google Scholar using an iterative combination of the keywords “transport noise,” “rail noise,” “urban,” “health,” “well-being,” and “annoyance,” yielding 109 records. Due to the broader scope and higher duplication rates in Google Scholar, each search was capped at the first 100 articles. After screening, 82 articles were excluded, leaving 27 retained. Following full-text evaluation, 62 out of 122 articles were excluded due to lack of relevance in at least one of the categories: noise sources, health outcomes, or mitigation strategies. This resulted in a refined dataset of 60 articles. An additional 14 articles were incorporated through snowball sampling of the initial 60 included articles, resulting in a final selection of 74 articles for inclusion in the scoping review [Figure 1].

Figure 1.

Retrieval and screening process (author’s original work created using Microsoft PowerPoint, Microsoft Corporation, Redmond, WA, USA; latest version).

Literature Review Limitations

The limitations of this scoping review primarily stem from its geographic focus on European countries, which restricts the generalizability of the findings to other regions where transportation systems, environmental conditions, and sociocultural contexts may differ. As a scoping review, the analysis is inherently dependent on the scope and quality of the identified literature.

RESULTS

Geographic Distribution of Studies

The majority of articles related to the health impacts of noise focused on the European region as a whole (29 articles), with the largest number of country-level studies in Germany (8), Switzerland (8), and Poland (5), followed by Denmark (3), the UK (4), Sweden (2), Italy (2), Belgium (2) Spain (2), Finland (2), and Norway (2). Single contributions were noted from Lithuania, Portugal, France, the Netherlands, and Slovakia [Figure 2].

Figure 2.

Countries of focus (author’s original work created using Microsoft PowerPoint, Microsoft Corporation, Redmond, WA, USA; latest version).

Health Effects of Transportation Noise

To ensure conceptual clarity and consistency across the reviewed literature, the following definitions are provided. Mental health is defined as “a state of emotional and psychological well-being allowing someone to function in society and cope with the demands of daily living”.[15] Well-being more broadly refers to how individuals experience and evaluate their lives and specific daily activities.[16] Cognitive function refers to the mental processes involved in acquiring, processing, and using information, including attention, memory, learning, and reasoning.[17] In this review, mental performance is used more specifically to describe task-based cognitive outcomes, such as reading comprehension, concentration, and performance on specific cognitive tasks in noisy environments. Although these terms are sometimes used interchangeably in the literature, this scoping review distinguishes between them to ensure consistency and reflect the different outcome dimensions examined across studies.

Biological Mechanisms

Transportation noise acts as a chronic environmental stressor, activating both the hypothalamic–pituitary–adrenal (HPA) axis and the autonomic nervous system (ANS). This triggers the release of stress hormones such as cortisol and catecholamines, which initiate a cascade of physiological responses, including increased heart rate, elevated blood pressure, and sustained sympathetic activation. Collectively, these responses contribute to cardiovascular strain.[18,19] At the vascular level, these stress responses promote endothelial dysfunction by reducing nitric oxide bioavailability and increasing susceptibility to vasoconstriction, while simultaneously triggering inflammatory signaling pathways and oxidative stress.[20] These processes are exacerbated further by night-time noise exposure, which disrupts sleep architecture and impairs physiological recovery, in-turn amplifying neurohormonal imbalance and cardiometabolic dysregulation.[18] Chronic exposure to transport noise has also been associated with molecular and cellular changes, such as increased production of reactive oxygen species (ROS) and activation of proinflammatory cytokines. There is also emerging evidence of changes in circadian regulation and gene expression patterns.[19] These mechanistic pathways provide the physiological basis for the various health issues associated with transport noise exposure.

These pathways are not only theoretical, but are also supported by epidemiological evidence demonstrating consistent associations between transport noise exposure and cardiovascular outcomes. Large-scale cohort studies show an increased risk of cardiometabolic disease with long-term exposure to road traffic noise,[21] while case–control analyses further support the association between chronic noise exposure and adverse health outcomes.[22] These findings reinforce the biological plausibility of noise as an environmental risk factor, linking stress-mediated physiological responses to observed population-level health effects.

Annoyance

The relationship between noise exposure and annoyance has been widely studied, with models forecasting the proportion of individuals significantly affected by noise in relation to its intensity. Metrics such as the day-night average sound level (L_DN) are commonly used to assess this relationship. Guski et al.’s[23] review of studies on road traffic, aircraft, and rail noise found moderate evidence of a link between noise levels and annoyance for aircraft and rail noise, but a weaker association for road traffic noise. Annoyance levels are heightened when individuals are exposed to both road and rail noise simultaneously and urban morphology also influences annoyance. Camusso et al. [24] demonstrated that road traffic noise often masks tramway noise on wider streets, whereas tramway noise tends to dominate on narrower, U-shaped streets, thereby increasing annoyance levels. These findings emphasize the importance of considering urban street configurations in noise management strategies.

The health impact of noise annoyance is significant. Tainio[13] quantified the burden of road traffic noise in Warsaw, linking it to disability-adjusted life years (DALYs) through cardiovascular disease, sleep disturbances, and annoyance. While the study focused on road traffic, it also opened up the possibility of exploring other noise sources, such as railways and airports. Past studies have shown that annoyance levels vary by source and intensity. For instance, 15% of individuals find road traffic noise highly annoying at a noise level of 60 dB(A) day–evening–night (L_DEN), compared to 17.4% for railway noise and 36% for aircraft noise.[3] Héritier et al.[25] found that sleep disturbances and annoyance significantly affect health-related quality of life (HRQoL), emphasizing the complex interplay of acoustic and nonacoustic factors. Furthermore, annoyance levels have increased over time for all types of transportation noise, with aircraft noise showing the most significant rise.[23] This trend is partly attributed to methodological changes, such as the transition from 5-point verbal scales to 11-point numeric ones.

Sleep Disturbance

Exposure to noise at night can severely disrupt sleep by delaying sleep onset, causing awakenings, or altering sleep architecture. Data reported under the END show that noise-induced sleep disturbances in EU cities with populations over 250,000 have resulted in a total loss of 903,000 DALYs.[26] Brink et al.[27] revealed strong associations between night-time noise levels (L_NIGHT) and self-reported sleep disturbances, with the greatest impact being caused by aircraft noise, followed by railway and road traffic noise. Other significant factors include noise intermittency and bedroom location, with exposure at the maximum façade point being a critical predictor of sleep disruption.

The SiRENE study (Short and Long Term Effects of Transportation Noise Exposure) examined the impact of transportation noise exposure on annoyance, sleep disturbances, and cardiometabolic risks. Röösli et al.[28] concluded that night-time noise exposure has more profound long-term health effects than daytime exposure, likely due to reduced habituation to autonomic arousal, such as increases in heart rate during disturbed sleep. Pirrera et al.[29] examined methods for measuring nocturnal awakenings, including electroencephalography (EEG) and self-reports. These findings showed that noise more frequently disrupts the lighter stages of sleep, such as stage N1 (light sleep) and stage N2 [intermediate non-rapid eye movement sleep (NREM)], than the deeper stages, such as slow-wave sleep (SWS). Long-term exposure can lead to partial sleep deprivation and disrupt natural sleep–wake cycles, which has a negative impact on health and well-being.

Cognitive Function

Noise exposure can impair cognitive processes, particularly in children and vulnerable populations. Studies have demonstrated that due to its intensity and unpredictability, aircraft noise significantly disrupts children’s reading comprehension and concentration more than road traffic noise.[30] Cognitive impairments resulting from noise exposure are often mediated by disturbed sleep, which induces fatigue and reduces cognitive performance.[31] Direct stimulation of brain regions such as the reticular activating system by traffic noise has been shown to impact mental health, as has indirect stimulation through sleep deprivation, annoyance, and stress, all of which are associated with conditions such as depression and anxiety.[1]

Aasvang et al.[32] investigated the impacts of structurally radiated noise from railway tunnels on residents in Norway, finding that 25% of respondents experienced annoyance, with 19.7% reporting slight annoyance and 4.5% moderate annoyance. Additionally, 3% of respondents reported difficulty falling asleep due to noise-related sleep disturbances, and 4% reported awakenings. Annoyance levels were influenced by the frequency of freight trains passing by and the presence of sound-insulated windows. Paradoxically, the latter heightened annoyance due to reduced background noise indoors.

Cardiovascular Effects

Noise exposure is increasingly recognized as a risk factor for cardiovascular diseases, including hypertension and coronary heart disease. Reviews of the current literature consistently report an association between transportation noise and adverse cardiovascular outcomes.[28,33] Meta-analytical evidence further supports this relationship by demonstrating an exposure–response pattern, whereby cardiovascular risk increases by approximately 8% for every 10 dB(A) increase in L_DEN, even at relatively low exposure levels.[9,34] Empirical studies also support these associations. For example, Fuks et al.[35] showed that road traffic noise contributes independently to the risk of hypertension through stress-mediated physiological pathways, while Foraster et al.[36] linked chronic noise annoyance to reduced physical activity, highlighting a behavioral mechanism that influences cardiometabolic health. Vulnerable groups, including women and individuals with pre-existing chronic conditions, appear to be disproportionately affected. Evidence from specific population groups further reinforces these findings. For example, Liu et al.[37] demonstrated significant positive associations between long-term traffic noise exposure and increased diastolic blood pressure in children, indicating that cardiovascular effects may occur early in life.

Importantly, the strength of the evidence base is supported by the prevalence of longitudinal and analytical study designs. Prospective cohort studies show that long-term exposure to transport noise increases the risk of hypertension, adiposity, and cardiovascular disease.[21,38] Alongside meta-analytical findings, these results suggest a robust and consistent link between chronic noise exposure and adverse cardiovascular health outcomes. However, evidence for other outcomes, such as metabolic and oncological effects, remains comparatively limited.

Other Well-Being-Related Effects

Throughout life, health is influenced by various factors, including social and economic circumstances, genetic predispositions, the physical environment and individual behavior. These elements are widely recognized as key determinants of health. Within the physical environment, noise is a common source of impairment to daily life and well-being.[4] Khreis et al.[39] highlight that traffic noise, primarily from motor vehicles, is associated with various adverse health outcomes, such as all-cause mortality, cardiovascular diseases, annoyance, sleep disturbances, cognitive impairment in children, and mental health issues. They emphasize that exposure to traffic noise is not only a source of physical ailments but also contributes to psychological stress and reduced quality of life in urban populations.

Epidemiological evidence accumulated over the past few decades suggests a positive correlation between exposure to traffic noise in residential areas and adverse health outcomes.[40] Sleep deprivation has been shown to disrupt hormonal regulation, specifically affecting leptin and ghrelin, which influences metabolism. Furthermore, sleep deprivation can diminish energy expenditure by impacting thermoregulation and inducing fatigue.[41] Epidemiological investigations consistently demonstrate an association between inadequate sleep duration and obesity. A study involving middle-aged Danish adults in the 1990s revealed a substantial body of evidence linking road traffic noise to potential adverse health effects.[42] The research revealed statistically significant positive correlations between road traffic noise and various obesity measures. Follow-up studies have highlighted connections between traffic noise and increased body weight and waist circumference, with these associations being particularly pronounced in individuals who were already classified as obese at the start of the study.[38] Further health-related studies investigated the impact of transportation noise, presenting compelling evidence of its adverse effects on blood pressure, particularly during night-time exposure.[43,44] Taken together, these findings suggest an elevated risk of hypertension, a major independent risk factor for events such as myocardial infarction and stroke, in association with environmental noise.

Hegewald et al.[22] found evidence of an increased odds ratio (OR) for estrogen receptor-negative (ER–) breast cancer in women aged ≥ 40 living in the Frankfurt, Germany airport area with 24-hour aircraft exposure of 55–59 dB(A). Here, an increase in risk of 5% was observed per 10 dB(A) increase in 24-hour aircraft noise exposure. However, this was the only study that linked noise exposure to cancer in our scoping literature review. Furthermore, the study was based solely on insurance records and had limited access to information regarding confounding factors. Therefore, we acknowledge this finding as an outlier in our study, as we found no other studies corroborating it. In the context of road traffic and diabetes, Sørensen et al.[21] discovered a statistically significant connection between prolonged exposure to road traffic noise at one’s residence and an elevated risk of diabetes. These findings suggest that reducing the overall population’s exposure to road traffic noise through various initiatives could lead to health improvements.

Summary of Health-Related Effects

[Figure 3] summarizes the distribution of health impacts examined in the reviewed studies. Annoyance was the most frequently studied outcome, appearing both as a noise-related issue and as a downstream effect of other noise-related categories, including sleep disturbances (the second most studied noise-related issue), cognitive function, and other well-being factors as mentioned above in the sections “Annoyance,” “Sleep Disturbance,” and “Cognitive Function.” For clarity, related outcomes were aggregated into broader categories, which are consistent with the structure of the scoping review. Hypertension, blood pressure changes, and ischemic heart disease were synthesized under cardiovascular outcomes, while studies addressing attention, learning, and school performance were grouped under learning impairment and cognitive disruption. Mental performance appears only three times in the reviewed studies and was grouped with stress-related outcomes, as both reflect the psychological and physiological strain that noise exposure can induce, with stress often acting as the pathway linking noise to reduced mental performance. Premature mortality is discussed in the literature as a consequence of long-term noise exposure, so it is addressed in the text rather than presented as a separate category.

Figure 3.

Noise-related health risks identified in retained studies (author’s original work created using Microsoft PowerPoint, Microsoft Corporation, Redmond, WA, USA; latest version).

Overview of ROSES-Based Scoping Review Results for Health Effects of Noise

The 42 articles discussed above are listed in Table 2, along with the geographical area of the study participants, the study focus, the type of noise exposure, the health effect, and the method of the reviewed study. To improve the interpretability of the reviewed evidence, the included studies were categorized according to their methodological design and the strength of the evidence they provide. Category A comprises longitudinal and analytical epidemiological studies, including prospective cohort and case–control designs. These designs allow for stronger causal inference due to their ability to establish temporal relationships between noise exposure and health outcomes. Category B includes cross-sectional studies, which provide valuable insights into the associations between transport noise and health indicators, but which are limited in their ability to infer causality due to the simultaneous measurement of exposure and outcome. Category C1 encompasses synthesis-based and empirical studies that provide supporting evidence, including systematic reviews, meta-analyses, experimental studies, and health impact assessments. While these studies offer valuable insights into exposure–response relationships and underlying mechanisms, they usually rely on aggregated data, modeled scenarios, or controlled conditions rather than direct longitudinal observation. Finally, category C2 consists of conceptual, methodological, and policy-oriented studies that provide theoretical frameworks, assessment methodologies, and planning perspectives, but do not generate primary empirical evidence on noise-related health effects. This classification system allows the strength and nature of the available evidence to be differentiated more clearly, thereby supporting a more nuanced interpretation of the relationship between transportation noise and health outcomes.

Table 2.

Summary of ROSES-based scoping review on noise effects (author’s original work created using Microsoft Excel, Microsoft Corporation, Redmond, WA, USA; latest version)

Ref. no.	First author	Year	Country of focus	Focus point	Noise exposure	Health effect	Method	Study design category
1	Münzel	2014	European regions	Noise effect	Environmental noise	Cardiovascular issues	Narrative review	C1
2	Sutcliffe	2021	Germany	Noise effect	Environmental noise	Coronary disease, depressive symptoms	Pilot/interdisciplinary study	C1
3	Basner	2018	European regions	Noise effect	Environmental noise	Sleep disturbance	Systematic review + meta-analysis	C1
4	Seidler	2017	Germany	Noise effect	Road, rail, aircraft	Mental performance	Case–control study	A
5	Lechner	2019	European regions	Noise effect	Road, rail, aircraft	Annoyance	Cross-sectional study	B
6	Houthuijs	2014	European regions	Noise effect	Road, rail, aircraft	Annoyance, sleep disturbance, cardiovascular diseases, cognitive function	Health Impact Assessment (HIA)	C1
9	Babisch	2014	Germany	Noise effect	Road	Coronary heart disease	Meta-analysis	C1
10	Mucci	2020	European regions	Noise effect	Environmental noise	Mental performance	Systematic review	C1
12	Tong	2021	United Kingdom	Noise effect	Environmental noise	Annoyance	Cross-sectional quantitative study	B
13	Tainio	2015	Poland	Noise effect	Road, rail	Cardiovascular issues, well-being	Health impact modeling study	C1
21	Sørensen	2013	Denmark	Noise effect	Road	Physical change	Prospective cohort study	A
22	Hegewald	2017	Germany	Noise effect	Road, rail, aircraft	Breast cancer	Case–control Study	A
23	Guski	2017	European regions	Noise effect	Road, rail, aircraft, wind turbines	Annoyance	Systematic review + meta-analysis	C1
24	Camusso	2016	Italy	Noise effect	Road	Annoyance	Cross-sectional field study with statistical model	B
26	Ristovska	2013	European regions	Noise effect	Environmental noise	Sleep disturbance	Narrative Review	C1
27	Brink	2019	Switzerland	Noise effect	Road, rail, aircraft	Annoyance	Cross-sectional epidemiological study	B
28	Röösli	2017	Switzerland	Noise effect	Road, rail	Annoyance, sleep disturbance, cardiovascular diseases	Interdisciplinary study overview (survey, experimental and cohort components)	C1
29	Pirrera	2010	Belgium	Noise effect	Road	Sleep disturbance	Narrative Review	C1
30	Clark	2006	European regions	Noise effect	Aircraft	Cognitive function	Cross-sectional study	B
31	Mac Domhnaill	2021	European regions	Noise effect	Road	Cognitive function	Cross-sectional study	B
32	Aasvang, Gunn Marit	2007	Norway	Noise effect	Railway	Annoyance, sleep disturbance	Cross-sectional survey study	B
33	Recio	2016	European regions	Noise effect	Road	Cardiovascular, respiratory, and metabolic health	Narrative Review	C1
34	Vienneau	2015	European regions	Noise effect	Road, rail, aircraft	Heart disease	Systematic review + meta-analysis	C1
35	Fuks	2011	Germany	Noise effect	Road, rail	Blood pressure	Cross-sectional analysis (within cohort)	B
36	Foraster	2016	Switzerland	Noise effect	Road, rail, aircraft	Annoyance	Prospective cohort study	A
37	Liu	2014	European regions	Noise effect	Road, rail	Blood pressure	Cross-sectional analysis (within cohort)	B
38	Christensen	2015	Denmark	Noise effect	Road	Physical change	Prospective cohort study	A
39	Khreis	2016	European regions	Noise effect, Noise mitigation	Road, rail	Aggression, stress	Literature review	C1
40	Brink	2011	Switzerland	Noise effect	Road, rail, aircraft	Well-being	Cross-sectional epidemiological study	B
41	Fyhri	2010	Norway	Noise effect	Road	Sleep disturbance, well-being	Cross-sectional survey with statistical modeling	B
42	Christensen	2016	Denmark	Noise effect	Road, rail	Physical change	Cross-sectional epidemiological study	B
43	Petri	2021	Italy	Noise effect	Road, rail, aircraft	Blood pressure, hypertension	Cross-sectional study with regression analysis	B
44	Dratva	2012	Switzerland	Noise effect	Road, rail, aircraft	Blood pressure	Cross-sectional analysis (within cohort)	B
45	Flanagan	2023	Sweden	Noise effect	Road	Annoyance	Health impact assessment (model-based study)	C1
63	Peeters	2021	European regions	Noise effect	Environmental noise	Creating soundscapes, using quiet areas	Conceptual and policy report	C2
66	De Vos	2016	European regions	Noise effect, Noise mitigation	Railway	Cardiovascular Issues, Blood Pressure, Stress, Annoyance	Technical and policy report	C2
75	Mitchell	2022	United Kingdom	Noise effect	Road, rail	Annoyance	Experimental study (online listening experiment)	C1
76	Bodin	2015	Sweden	Noise effect	Road	Annoyance, sleep disturbance	Cross-sectional epidemiological study	B
80	Franco	2010	European regions	Noise effect	Road	Annoyance	Methodological framework study	C2
87	Gössling	2016	European regions	Noise effect	Environmental noise	Cognitive function, well-being	Conceptual theoretical paper	C2
88	Seidler	2023	Germany	Noise effect	Railway	Well-being	Systematic review with analytical modeling	C2
89	Frei	2014	Switzerland	Noise effect	Road	Sleep disturbance	Observational study with experimental sleep measurements	C1

Overall, the distribution of study designs reveals an evident imbalance in the structure of the reviewed literature. Cross-sectional studies (Category B) represent the largest group (n = 18), indicating a strong reliance on associative evidence when assessing the relationship between transportation noise and health outcomes. Studies with higher inferential strength, including longitudinal and analytical epidemiological designs (Category A), are comparatively fewer in number (n = 6). However, they provide more robust evidence for causal relationships. A substantial proportion of the literature consists of synthesis-based and modeling approaches (Category C1; n = 16), including systematic reviews, meta-analyses, and health impact assessments. These approaches support exposure–response relationships and mechanistic interpretation but are not based on primary longitudinal observation. Conceptual and policy-oriented studies (Category C2) account for a smaller proportion (n = 5) and contribute theoretical frameworks and planning perspectives rather than empirical evidence. This distribution highlights the predominance of cross-sectional and synthesis-based research, while indicating a relative lack in longitudinal studies capable of establishing causal links between transportation noise exposure and health outcomes.

Noise Mitigation Strategies

Urban planning is a multidimensional discipline that considers various factors such as demographics, safety, mobility, and economic sustainability.[45] However, noise control is often overlooked, particularly in the early stages of planning. The focus of addressing noise-related issues tends to be reactive, with the aim of reducing noise levels to prevent adverse health effects such as cardiovascular diseases, sleep disturbances, annoyance, and concerns about general well-being.[46]

Barrier Solutions for Road and Rail Noise

Of all the engineered interventions, acoustic barriers are among the most direct and effective measures for reducing transportation noise in residential and mixed-use areas. Innovations in noise-barrier geometry have proven highly effective in improving acoustic attenuation without increasing the height of the barriers. Y- and T-shaped barrier caps, for example, enhance acoustic attenuation by improving diffraction and reflection properties, achieving up to 7 dB(A) higher insertion loss (IL) than flat-top barriers of equal height.[47]

In urban contexts where visual impact and material efficiency are key concerns, sustainable barrier solutions are increasingly favored. Life-cycle assessments of low-height (85–110 cm) barriers revealed ILs between 8 and 11 dB(A), meeting Class A3 absorption standards while substantially lowering embodied energy and CO₂ emissions compared to conventional concrete walls.[48] Hybrid mitigation systems combining reflective acoustic barriers and vegetated berms have demonstrated total attenuation of 10–20 dB(A). The synergy between foliage absorption and structural diffraction highlights the importance of multifunctional designs in shaping sustainable acoustic environments through the integration of landscape architecture, acoustic engineering, and urban design.[49]

Railway Noise Mitigation Strategies

Noise emitted by urban rail transport is one of the four main sources of noise in urban areas (along with road, air, and industrial noise) and is, therefore, subject to cyclical quantification and control. Acoustic models simulate the emission and propagation of rail noise in various operating conditions. This is essential for strategic noise mapping and planning noise mitigation strategies.[50] While offering significant environmental and congestion benefits, high-speed railways contribute to noise pollution through aerodynamic, wheel–rail interaction, and pantograph noise. This highlights the need for continuous innovation in noise mitigation strategies such as rail grinding, noise barriers, aerodynamic fairings and improved rolling stock design.[51]

The use of elastic materials such as rail pads, under-sleeper pads (USPs), and under-ballast mats has been shown to improve track resilience and reduce noise and vibrations. These materials can also significantly lower railway maintenance costs over time, making them an effective solution for noise mitigation in urban rail systems.[52] A study by Watson et al.[51] highlights that while trams, buses, and cars contribute to urban noise, the intensity varies based on operational conditions. Their analysis found that trams generate higher noise levels due to rail–wheel interaction at speeds of 30 m/h, whereas buses surpass trams in noise emissions during acceleration. Importantly, maintaining track infrastructure and road surfaces is crucial for minimizing noise, as poorly maintained tracks can significantly elevate tram noise levels​. Sonic Crystals Acoustic Screens (SCAS), for instance, provide frequency-specific noise reduction through band gaps. These screens, designed with periodic arrays of scatterers, block certain frequencies effectively. However, designing SCAS remains complex due to acoustic phenomena. Recent advancements, such as the finite-element method (FEM), have made it possible to create more practical designs for real-world conditions.[53]

Lacasta et al. [54] conducted on-site measurements to evaluate the acoustic effectiveness of modular noise barriers that incorporated vegetation. They reported average sound absorption coefficients (α) of approximately 0.7, which surpassed the results of laboratory tests on systems without or with lower vegetation density. Environmental noise prediction software using these coefficients demonstrated enhanced performance in parallel arrangements, improving sound attenuation compared to reflective barriers. Design improvements to railway noise mitigation focusing on optimizing rail pads and ballast stiffness have demonstrated that enhancing rail pad stiffness and ballast damping properties can significantly reduce railway noise.[55] Gužas et al.[56] highlight that innovative acoustic barriers incorporating cone elements can effectively manage low-frequency noise near railway infrastructure. In Slovakia, noise barriers tested under ISO 10847 and EN 1793-6 standards achieved IL values of 19.1 dB(A), demonstrating strong sound insulation performance.[57] Ngamkhanong et al.[52] examined the use of elastic track elements, such as rail pads, USPs, and under-ballast mats, to improve track resilience and reduce vibration and noise. Through a 30-year life-cycle cost analysis, they found that, despite a higher initial cost, USPs reduce annual track maintenance costs by around 50% and pay back the additional investment within approximately 4 years. Short acoustic barriers tailored for railway noise sources involve optimizing geometry and incorporating porous materials to enhance performance. Numerical modeling using boundary element methods (BEMs) has shown that curved barriers with porous layers achieve an IL of over 10 dB(A) across a wide frequency range.[58,59]

Green Infrastructure as a Mitigation Tool

Urban vegetation can measurably reduce traffic noise, with the effectiveness of this reduction depending on the structure, size, and density of the planting. Trees and shrubs, especially evergreen conifers, disperse sound best and are effective year-round. Dense vegetation can attenuate noise by roughly 5–10 dB for every 30 linear meters of forest buffer away from the noise source. Even relatively narrow belts (approximately 15 meters wide) and hedges can produce measurable reductions, whereas sparse cover, such as lawns, is largely ineffective. Guidelines recommend a buffer of around 6–15 meters of mixed evergreen trees and shrubs alongside moderate-speed road and a wider buffer of 20–30 meters along high-speed roads. The effectiveness of the buffer tails off beyond 300–500 m.[60] The acoustic performance of green areas depends on the structure and density of vegetation, as well as the distance from the source. In Rey-Gozalo et al.’s[49] field measurements, a densely foliated green area in Madrid had to sit roughly 70 meters from the centerline of a major road and more than 30 meters from a residential street to fall below the 55 dB(A) quiet-area threshold. In smaller Spanish and Portuguese towns, green areas located 40 meters or more from main roads reached the recommended quiet-area levels.

Green infrastructure plays a vital role in reducing urban noise. The SALVE pilot study in Bochum examined how the quality of urban acoustic environments relates to residents’ health, concluding that high-quality soundscapes are achieved not simply by lowering decibel levels but by promoting natural, biophonic sounds while limiting anthropogenic noise.[2] Having a bedroom on the quiet side of a dwelling or access to a quiet façade has been shown to substantially reduce noise annoyance and sleep disturbance, particularly among noise-sensitive residents.[61] This is relevant to health and well-being, since annoyance and sleep disturbance are key mediators of the effect of noise on HRQoL.[25]

In the discussion of sound-related ecosystem services, large vegetated areas or natural biotope complexes provide natural acoustic environments and noise exclusion as a consequence of noise source exclusion. The impact of large-scale preservation areas on the acoustic environment is a largely unexplored research area within European noise action planning.[62] The public appreciates quiet areas, which have a positive effect on well-being; however, there is no evidence of regulations ensuring that designated quiet areas will remain quiet tomorrow.[63]

Noise Action Plans and Urban Noise Mitigation

Cucurachi et al. [64] highlight that road transportation is the largest contributor to land-based noise footprints, with passenger cars accounting for about 95% of the total noise impacts in Switzerland. Their study shows that electrifying the vehicle fleet could reduce urban noise impacts by about 55%, particularly in low-speed areas. This demonstrates the potential of sustainable mobility strategies to mitigate noise pollution due to reduced mechanical noise compared to traditional combustion engines.[64] Reducing speed limits on roads is another effective approach. Borowska-Stefańska et al. [65] found that reducing speed limits on roads exceeding 50 km/h can mitigate road noise without disrupting the efficiency of the urban transport system. In addition to technological and traffic management measures, policy-based approaches play a central role in urban noise mitigation.

NAPs are a key policy mechanism within the END (2002/49/EC). They serve as administrative tools for reducing environmental noise in urban areas, designate “noise zones” based on strategic noise mapping, and require interventions such as noise insulation for new developments and transportation planning adjustments.[45] Analysis and modeling of typical spatial alternatives for roadway noise mitigation provides municipalities with a structured, analytical pathway for integrating noise mitigation into specific urban cases.[46] NAPs combine technical interventions, such as barriers, low-noise pavements, and vegetation, with participatory urban governance to ensure that mitigation aligns with public health objectives and community expectations.[66] The END requires agglomerations exceeding 100,000 inhabitants to prepare strategic noise maps and NAPs. These instruments rely on the L_DEN indicator to standardize exposure assessments and must be reviewed every 5 years, thereby reinforcing continuous improvement in urban noise management.[67] NAPs are most effective when supported by transparent governance and citizen involvement. de Vos[68] emphasizes that integrating socioeconomic data, stakeholder input, and environmental monitoring enhances the legitimacy and adaptability of long-term urban noise mitigation strategies.

This study examined the NAPs of Bochum, Dortmund, and Duisburg, three major cities in Germany’s Ruhr region, to assess how municipalities implement noise mitigation strategies. Aligned with the EU END, these plans integrate multiple approaches to reducing transportation noise and improving urban soundscapes. The analysis identified a combination of traffic management measures, green infrastructure applications, rail noise control interventions, and passive noise barriers.[69,70] Reducing road speed limits is widely recognized as an effective noise mitigation strategy, although the reductions achieved are modest. The NAPs of Dortmund and Duisburg have introduced 30 km/h speed limits on busy inner-city roads (typically 50 km/h), which exceeded 70 dB(A), in order to reduce traffic noise without significantly impacting urban mobility. Such slight speed reductions do not disturb the equilibrium of the urban transport system, as city transport networks can accommodate localized disruptions. However, a more comprehensive assessment should include analyses of changes in noise levels on alternative routes used by diverted traffic.[69,71] In contrast, Bochum has prioritized nighttime restrictions for heavy vehicles in densely populated areas to reduce peak noise exposure during rest hours.[70] Road surface improvements, including the widespread adoption of low-noise asphalt, have also been implemented. Duisburg has further prioritized resurfacing key routes with porous asphalt.[69]

Typical traffic management measures implemented in NAPs, including in Dortmund, Bochum, and Duisburg, are 30 km/h zones, coordinated traffic lights, and traffic-calming roundabouts. These measures yield consistent yet moderate acoustic benefits. Empirical evidence indicates reductions of 2–4 dB(A) following decreases in the speed limit and 1–3 dB(A) from improved intersection flow. However, excessive use of speed bumps may locally increase peak levels due to braking and acceleration events.[72] Quantitative modeling across European case studies shows that coordinated signal timing and road narrowing can each yield 1–3 dB(A) reductions in noise levels, while implementing 30 km/h zones across residential districts may achieve average decreases in L_DEN values of up to 3 dB(A).[72] Rail noise control measures have also been prioritized. Both Dortmund and Duisburg have invested in track maintenance techniques such as rail grinding and wheel polishing to reduce rail-induced noise and vibrations.[60,73] Both cities have also increased their use of elastic rail pads and USPs, which effectively absorb structural vibrations and reduce noise pollution in residential areas.[70,71] In addition to strategies for mitigating traffic and rail noise, passive noise control measures are widely implemented. Duisburg has focused on constructing barriers along railway corridors and main roads to reinforce noise insulation in highly exposed areas,[69] while Bochum and Dortmund offer cost-sharing or cost-replacement incentives for soundproof windows in residential buildings in noise-exposed areas.[70,71]

Green infrastructure has emerged as a key tool for mitigating noise within NAPs. Bochum has actively integrated urban green spaces into high-noise areas, using vegetative buffers along major roads and residential areas to absorb and diffuse sound waves, thereby enhancing visible and nearby green.[70] Similarly, Dortmund and Duisburg have emphasized the importance of tree-lined streets and vegetative noise barriers, which enhance environmental sustainability and improve acoustic performance.[69,70] From the analysis of these three Ruhr-region NAP cases, the most commonly adopted strategies include speed limit reductions and traffic rerouting for sound source reduction, increased integration of green infrastructure as a natural noise buffer, the widespread use of low-noise pavement and track maintenance techniques for propagation reduction, and the expansion of barrier and insulation programs in high-exposure zones.[69,70]

Urban Acoustic Environment Enhancements

Gołda et al.[74] demonstrated through transport modeling of a scenario-based approach to the Warsaw urban road network that infrastructure development and network reconfiguration can reduce high noise levels. Their case study showed that the proportion of active road network links exposed to traffic noise levels exceeding 75 dB(A) fell from 2.7% in 2015 to 1.9% in 2020, reflecting the impact of planned infrastructure expansion and traffic redistribution. Mitchell et al.[75] explored soundscape complexity and found that integrating natural sounds into urban environments reduces annoyance levels. Finally, effective mitigation of railway-induced vibrations requires environmental impact assessments (EIAs). de Vos and Pirrera et al.[29,68] call for the development of affordable and accurate prediction models and solutions to address these challenges in expanding urban areas.

Summary of Mitigation Strategies

[Figure 4] illustrates the frequency with which noise mitigation strategies were addressed in the reviewed articles, highlighting the range of approaches discussed for reducing transport noise exposure and its associated health risks. Acoustic barriers were the most frequently reported mitigation measure, appearing in nine studies, which highlights their central role as a primary structural intervention for reducing noise exposure in transport environments. Urban greenery and vegetation, along with wheel and rail maintenance or rail material interventions, appeared in four studies, representing important complementary strategies. Vegetation-based measures are discussed for their potential to enhance sound absorption (propagation reduction) and improve exposure by improving environmental quality, while rail-focused material interventions target noise and vibration reduction at the source.

Figure 4.

Mitigation strategies studied across articles (author’s original work created using Microsoft PowerPoint, Microsoft Corporation, Redmond, WA, USA; latest version).

Several operational and infrastructural strategies aimed at reducing noise at its source, including traffic flow management, traffic speed reduction, traffic distribution optimization and road, track, or pavement design, each appeared three times. This indicates consistent recognition of their relevance in managing noise through system-level adjustments. Other measures, such as soundproofing buildings, installing quiet façades, conducting noise mapping, planning or zoning and using seismic or vibration-related materials, were each mentioned twice. This reflects their role as more targeted or context-specific solutions for noise mitigation.

Only one study identified the electrification of transport as a noise mitigation measure. Although it is discussed less frequently in the reviewed literature, it remains a potentially important long-term strategy due to its combined benefits in reducing noise and air pollution emissions. However, the trend toward artificial external motor sounds in electric vehicles, coupled with the fact that tire and wind noise do not decrease in electric vehicles compared to ICE vehicles, suggests that the reduction of source noise through electrification may be limited. Overall, the distribution of mitigation strategies indicates a strong emphasis on structural interventions, particularly acoustic barriers, followed by vegetation-based solutions and rail material enhancements. Operational measures, such as traffic speed management and traffic flow optimization, also feature prominently, highlighting the importance of integrating physical, operational, and planning-based approaches to transport noise mitigation. These structural measures are complimented by optimization, highlighting a multifaceted approach to mitigating the environmental impacts of transportation systems, particularly in noise-sensitive urban and rail-dense regions.

Overview of ROSES-based Scoping Literature Review Results for Noise Mitigation Strategies>

Our review identifies 26 studies on sound mitigation, exploring interventions such as sound barriers, track and wheel modifications, material innovations, and spatial planning solutions. These studies suggest that access to quieter building facades, particularly those facing green or water spaces, significantly reduces annoyance and enhances well-being.[76] Together, these findings emphasize the importance of integrating noise mitigation measures into urban planning frameworks to improve public health outcomes. Table 3 compiles studies focusing on mitigation strategies, including both technical and nature-based interventions designed to reduce exposure to noise and associated health risks. Together, these tables provide a comprehensive overview of the evidence base, illustrating the scoping review’s dual focus on the adverse health consequences of noise and the effectiveness of existing mitigation measures.

Table 3.

Summary of ROSES-based Scoping Review on Mitigation Strategies (Author’s Original Work Created using Microsoft Excel, Microsoft Corporation, Redmond, WA, USA; Latest Version)

Ref. no.	First author	Year	Country of focus	Noise source	Health effect/mitigation strategy	Intervention pathway
7	João Lázaro	2022	Portugal	Railway	Acoustic barriers	Propagation
8	Le Bescond	2021	France	Road	Traffic flow management, vehicle technology improvements	Not applicable (modeling study)
11	Lebiedowska	2005	Poland	Road, rail	Soundproofing buildings, enhancing green spaces	Not applicable (conceptual/classification study)
46	Ruiz-Padillo	2016	European regions	Road	Road design improvements, traffic management, acoustic barriers and shields	Mixed (source + propagation + exposure)
47	Pardo-Quiles	2020	Spain	Road	Noise barriers with optimized cap designs (Y-caps, T-caps, cylinders, trapezoids, rectangular caps)	Propagation
49	Rey-Gozalo	2023	European regions	Road	Vegetation-based noise attenuation; soundscape-oriented park design; use of foliage, berms, depressions, tree characteristics	Propagation
50	Komorski	2022	Poland	Railway	Wheel and rail maintenance, acoustic materials	Source
51	Watson	2018	European regions	Railway	Use of straight tracks, regular maintenance	Mixed (source + propagation + exposure)
52	Ngamkhanong	2019	United Kingdom	Railway	Rail pads, under-sleeper pads (USP), under ballast mats (UBM), elastic materials	Source
53	Castiñeira	2015	European regions	Road, rail	Acoustic barriers	Propagation
54	Lacasta	2016	Spain	Railway	Acoustic barriers	Propagation
55	Andrés, V. T.	2022	European regions	Railway	Rail geometry and track properties	Source
56	GÛzas	2010	Lithuania	Railway	Acoustic barriers	Propagation
57	Pultznerová	2021	Slovakia	Road, rail	Acoustic barriers	Propagation
58	Ouakka	2023	European regions	Railway	Seismic metamaterials	Propagation
59	Ouakka	2022	European regions	Railway	Improvement in the track, vibration-absorbing materials in soil (transmitter)	Mixed (source + propagation + exposure)
60	Łowicki	2025	Poland	Road	Urban greenery as noise attenuation measure (trees, shrubs, forests, green wedges)	Propagation
61	Van Renterghem	2012	Belgium	Road	Green belts	Exposure (receiver-side spatial design − quiet façade / dwelling orientation)
64	Cucurachi	2019	European regions	Environmental noise	Electrification of the transportation fleet	Source
65	Borowska	2023	European regions	Road	Speed limits	Source (traffic management − speed reduction)
67	Coelho	2006	Portugal	Road, rail, aircraft	Noise mapping, noise action plans, low-noise pavements, speed limits, land-use planning, traffic restrictions, acoustic barriers (outside dense urban areas), public awareness campaigns	Multiple (source + propagation + exposure), Primary: propagation/planning-level
72	Desarnaulds	2004	European regions	Road	Traffic calming (speed reducers, narrowing), 30 km/h zones, selective vehicle restrictions, roundabouts, traffic-light optimization, cycle-track redesign, low-noise driving	Source (traffic management measures)
73	Frost	2007	United Kingdom	Road, rail	Track and pavement design and maintenance, vehicle maintenance	Not applicable (assessment/measurement study)
74	Gołda	2017	Poland	Road, rail	Traffic distribution optimization, urban noise cost consideration	Source (transport system changes via infrastructure & traffic distribution scenarios)
78	Brink	2022	Switzerland	Road	Speed reduction (urban traffic calming)	Source (speed limit reduction/traffic management)

To improve the clarity and practical relevance of the mitigation strategies summarized in Table 3, the identified measures were classified according to both noise source and intervention pathway. Noise sources were categorized based on their primary origin, including road traffic, railway systems, and, where applicable, mixed transport environments involving multiple sources such as road, rail, and aircraft. Furthermore, the mitigation strategies were organized according to their position within the noise transmission chain, distinguishing between source, propagation, and exposure (receiver) interventions, as reflected in the reviewed studies. Source-level measures refer to strategies that directly reduce noise generation. These include traffic management approaches, such as speed reduction and flow optimization, as well as infrastructure- and vehicle-related modifications that influence emission characteristics (e.g., speed regulation studies and traffic management analyses). Propagation-based interventions act along the transmission path between the sound source and the receiver. They aim to attenuate or alter sound propagation through mechanisms such as acoustic barriers, vegetation buffers, and landscape design. These mechanisms influence reflection, absorption, and diffraction processes.[46,77] Exposure-based measures focus on reducing the impact of noise on the receiver. They typically use spatial planning and building design strategies. These include quiet façades, dwelling orientation, and the allocation of sensitive rooms to shielded sides. These strategies have been shown to significantly reduce annoyance and sleep disturbance in high-exposure environments (e.g., quiet façade studies). Additionally, several studies adopt an integrated, system-level approach, combining multiple intervention pathways through urban planning, infrastructure development, and policy-driven NAPs. This highlights the importance of coordinated strategies for effective noise mitigation.[46] The classification framework provides a coherent structure for comparing heterogeneous mitigation strategies, enhancing the interpretability of the scoping review by linking each intervention to its functional role within the overall noise control process.

In total, the reviewed mitigation studies show a clear distribution across intervention pathways. Propagation-based measures are the largest group (n = 10) and primarily focus on acoustic barriers, vegetation, and landscape-based attenuation strategies. Source-level interventions account for a substantial proportion (n = 7) and include traffic management, speed reduction, and rail- or vehicle-related modifications. A smaller number of studies (n = 5) adopt a mixed approach, combining multiple intervention pathways to reflect integrated planning and infrastructure strategies. By contrast, exposure-based measures are comparatively underrepresented (n = 1), indicating a limited focus on receiver-side interventions such as façade design and spatial planning. Additionally, a small subset of studies (n = 3) was classified as not directly applicable to a single pathway, as they focus on modeling, assessment, or conceptual classification rather than the implementation of specific mitigation measures. Overall, this distribution emphasizes the strong focus on propagation and source-level strategies in the literature, while highlighting a potential research gap in exposure-based interventions at the building and urban design scales.

Comparative Overview of Noise Mitigation Strategy Efficacy

[Figure 5] presents a comparative overview of the typical noise reduction effectiveness of the urban noise mitigation strategies commonly employed in this review, including an estimated dB(A) reduction. Acoustic barriers demonstrate the greatest potential for overall reduction, typically achieving values of 8–12 dB(A), which reflects their strong capacity to deflect noise away from target areas. Enhancements to barrier geometry enhancements (e.g., Y- or T-shaped caps) also demonstrate substantial effectiveness, typically achieving reductions of 4–8 dB(A). Vegetation belts of 15–20 m wide provide moderate attenuation of around 3–6 dB(A), offering acoustic and environmental perception benefits. Traffic speed adjustments, particularly reductions to 30 km/h, yield reductions of 2–5 dB(A). This is similar in scale to rail grinding and elastic rail pad solutions, which range between 3 and 6 dB(A), depending on track conditions. Low-noise or porous asphalt produces reductions of approximately 2–4 dB(A), making it a valuable roadway treatment for reducing tire–road interaction noise. While more variable, traffic flow optimization generally results in reductions of 1–3 dB(A), reflecting improvements achieved through smoother vehicle movement and less stop-and-go behavior. Overall, the figure shows that physical barriers made with porous materials, coupled with vegetation, and specialized rail or pavement engineering interventions tend to deliver the most substantial reductions. Operational source-control measures, such as speed management and traffic flow optimization, offer modest yet widespread contributions with lower time and material investment when integrated into broader urban noise mitigation strategies.

Figure 5.

Comparative effectiveness of urban noise mitigation strategies in typical dB(A) ranges (author’s original work created using Microsoft PowerPoint, Microsoft Corporation, Redmond, WA, USA; latest version).

The Link between Mitigation Strategies and Health Effects

[Figure 6] illustrates the conceptual framework underpinning this scoping review, which links transport noise sources to health impacts via noise propagation and exposure pathways. Noise generated by road, rail, and air transport propagates through the built environment via emission, reflection, and diffraction processes. This results in population exposure, which is characterized by commonly used metrics such as L_DEN, L_NIGHT, and dB(A). The health impacts reported in the reviewed studies, including annoyance, sleep disturbance, and cardiovascular outcomes, are consistently associated with these exposure characteristics. The reviewed literature discusses mitigation strategies that primarily modify noise propagation (e.g., acoustic barriers and vegetation) or reduce source noise and its temporal characteristics (e.g., speed reduction, low-noise pavements, traffic management, rail maintenance, and planning measures). While energetic renovations of buildings incorporating soundproof windows, roof, and façade soundproofing are widely applied measures, they cannot address the sheer number of buildings exposed to noise due to expense. Consequently, mitigation strategies primarily influence health outcomes by modifying source and propagation conditions.

Figure 6.

Conceptual linkage between noise, health, and mitigation strategies (author’s original work created using Microsoft PowerPoint, Microsoft Corporation, Redmond, WA, USA; latest version.

While the reviewed literature addresses health impacts and mitigation strategies largely in separate strands, several studies allow these dimensions to be linked through shared exposure characteristics. To synthesize these relationships, Table 4 summarizes associations between specific noise-related health impacts, exposure metrics emphasized in the reviewed studies, and mitigation strategies discussed in relation to these exposures.

Table 4.

Associations between Transport Noise, Health Impacts, and Mitigation Strategies based on Reviewed Studies (Author’s Original Work Created using Microsoft Excel, Microsoft Corporation, Redmond, WA, USA; Latest Version)

Health impact category	Exposure characteristics emphasized in reviewed studies	Mitigation strategies discussed in reviewed studies	Evidence basis in reviewed literature (examples)
Noise annoyance and reduced quality of life	Overall exposure levels (LDEN); persistent daytime noise	Acoustic barriers; speed reduction; traffic calming; low-noise pavements; traffic flow optimization	Reviewed studies consistently associate higher LDEN with increased annoyance and reduced quality of life, and discuss strategies for reducing levels as being relevant for reducing annoyance.[46,61,72,78]
Sleep disturbance	Night-time exposure (LNIGHT); maximum noise events (LMAX); frequency of nocturnal events	Rail and wheel maintenance; speed management; night-time traffic controls; source-based mitigation	Studies focusing on sleep outcomes emphasize nocturnal exposure and event-related noise, particularly from rail and road traffic, and highlight source-based mitigation measures as relevant.[51,52,65,79]
Cardiovascular and long-term health outcomes	Long-term cumulative exposure (LDEN, LNIGHT); chronic noise burden	Noise mapping and action plans; traffic reduction strategies; land-use planning; strategic green buffers	Reviewed epidemiological and planning-oriented studies link cardiovascular outcomes to long-term cumulative exposure, supporting the relevance of strategic, population-level mitigation approaches.[64,67,79]
Cognitive effects and vulnerable populations (e.g., children)	Daytime exposure near sensitive locations; speech interference; peak noise events	Soundproofing of buildings; traffic calming in sensitive areas; localized vegetation buffers	Studies addressing vulnerable populations highlight localized exposure reduction near residential and sensitive land uses, including building insulation and traffic calming measures.[11,46,78]
Mental health and well-being	Chronic exposure; perceived noise burden; sound quality	Green infrastructure; soundscape-oriented design; access to quieter environments	Several studies discuss associations between chronic noise exposure, perceived disturbance, and mental well-being, emphasizing mitigation strategies that improve perceived sound quality rather than level alone.[49,60,61]

DISCUSSION

Implications for Policy and Future Research>

Although the existing body of literature on the impact of transportation noise on physical and mental health has undoubtedly grown, there are still several critical gaps that need to be addressed. Recognizing and addressing these gaps is essential for improving our understanding of the relationship between transportation noise and health outcomes, and for informing future mitigation efforts. The unique characteristics of noise as a pollutant, with both physical and mental health effects, require a specific approach to assessment. To this end, noise annoyance is the preferred indicator for assessing the impact of traffic noise on human health because it makes the results more intelligible and applicable to urban planning and infrastructure development decisions.[80] Accordingly, many studies rely on self-reported measures of noise annoyance, but this has limitations in terms of linking annoyance to specific objective health outcomes. Thus, there is a need for more research that incorporates objective health measures. Linking subjective experiences of noise annoyance with quantifiable physiological markers could enhance the robustness of findings and provide a more comprehensive understanding of the health implications of transportation noise.

Limitations of Noise Action Plans

Although NAPs offer a structured approach to mitigating environmental noise in urban areas, there are several limitations that require further investigation. One key limitation is the lack of real-time noise monitoring and adaptive responses. Most NAPs rely on periodic noise mapping and extensive modeling, which may fail to capture the dynamic fluctuations in urban noise levels caused by hourly or seasonal variations, temporary construction activities, shifts in traffic patterns, or variations in sound quality. Future research should, therefore, explore integrating continuous noise monitoring approaches as a fundament for data-driven mitigation strategies. The 2025 Dortmund NAP supported research which involved longitudinal sound monitoring in 92 noise hotspots and quiet areas. This study found that noise distribution changed during the pre-dawn, daytime, evening, and deep-night time periods,[81] with peripheral areas acting as quiet biophonic reserves and urban green areas providing moderate attenuation in contrast to the urban core and main transport corridors.

Another challenge lies in the long-term effectiveness of noise mitigation measures. Even though interventions such as speed reductions, green infrastructure, and noise barriers initially improve the situation, there is limited research on their long-term effectiveness, particularly in the context of structural and demographic changes. Further studies should, therefore, assess the durability and adaptability of these strategies. Although these strategies are widely implemented in NAPs, empirical evidence shows that certain interventions can lead to measurable improvements in health-related outcomes. For instance, a longitudinal study conducted in Zurich revealed that reducing traffic speed limits from 50 to 30 km/h led to substantial reductions in both noise annoyance and self-reported sleep disturbance, as well as measurable decreases in noise exposure.[78] These findings suggest that relatively small reductions in sound levels can translate to meaningful improvements in perceived well-being and sleep quality at a population level.

Similarly, spatial and architectural interventions have been shown to play a critical role in mitigating the health impacts of noise exposure. Studies examining the “quiet side” effect demonstrate that access to a less exposed façade or courtyard can significantly reduce noise annoyance and sleep disturbance. For example, Bodin et al.[76] found that residents with access to a quiet façade reported lower risks of annoyance, concentration problems and poor sleep quality. Van Renterghem and Botteldooren[77] reported comparable findings, showing that the presence of a quiet side can contribute to reductions in both annoyance and sleep disturbance, particularly when bedrooms are oriented away from the primary noise source. Large-scale population studies further confirm these effects. For example, de Kluizenaar et al. [82] demonstrated that the presence of a relatively quiet façade can produce benefits equivalent to a reduction in noise exposure of approximately 5 dB(A). Additionally, intervention-based research within the QSIDE project indicates that deliberately creating quiet sides through urban design measures leads to measurable improvements in both acoustic conditions and residents’ subjective health responses.[83]

On a broader scale, health impact assessment approaches provide further evidence of the effectiveness of mitigation strategies. For example, Rossi et al. [84] demonstrated that traffic management interventions, including speed reductions and traffic flow optimization, can reduce the burden of cardiovascular disease, noise annoyance and sleep disturbance at a population level. However, the relationship between noise reduction and health improvement is not always straightforward. For instance, Barros et al.[85] discovered that, despite noise barriers reducing sound levels by up to 10 dB(A), corresponding reductions in annoyance were not consistently observed in all cases. This suggests that non-acoustic factors, such as visual impact, expectations, and social context, may influence the perceived effectiveness of mitigation measures. Similarly, Laszlo et al. [86] emphasize that direct evidence linking mitigation strategies to physiological health outcomes remains limited, highlighting the need for more longitudinal and intervention-based studies. Furthermore, NAPs frequently concentrate on general regulatory measures rather than localized, community-specific solutions. Different urban districts experience noise pollution differently based on land use, population density, and socioeconomic factors. Future research should, therefore, investigate how neighborhood-scale, customized interventions could be more effective in addressing noise pollution at a micro-level.

Finally, public awareness and stakeholder engagement remain underexplored in many NAPs. Effective noise reduction requires the cooperation of policymakers, urban planners, and the public. However, few studies have examined how participatory planning and community-driven initiatives could improve noise management. It is important that future research explores methods for increasing public engagement and compliance with noise mitigation policies.

Social Justice and Vulnerable Populations

Urban transport systems often disproportionately expose vulnerable populations to environmental hazards, including noise pollution, in a disproportionate way. This is particularly relevant in the context of railway noise. Gössling[87] highlights that transport-related noise is not merely an environmental issue, but also a social justice concern that disproportionately affects low-income neighborhoods and sensitive institutions, such as schools and hospitals. Urban planning priorities that favor motorized transport over nonmotorized options exacerbate this inequity, leaving pedestrians, cyclists, and nearby residents more vulnerable to health risks such as cardiovascular disease and cognitive impairment.

Cumulative Effects of Noise and Vibration

Seidler et al.[88] introduced a pragmatic approach to assessing the cumulative effects of railway-related noise and vibration by combining their equivalent noise levels. This energetic summation method has proven to be a conservative way of estimating overall annoyance, as opposed to more complex epidemiological models. Although there are some methodological limitations that require further verification, this approach provides a valuable tool for predicting health outcomes related to noise and vibration. Further research is encouraged to explore the combined effects of these factors on cardiovascular and mental health, as well as annoyance and sleep disturbances.

Vulnerable Populations and Health Disparities

Limited attention has been given to vulnerable populations, including children, the elderly, and those with pre-existing health conditions. There is also a notable lack of research addressing potential health disparities related to transportation noise and the socioeconomic factors that may amplify or mitigate its impact on different demographic groups. Of the articles reviewed, fewer than five focused on more vulnerable groups such as children or the elderly. Further research is required to improve our understanding of the association between road traffic noise exposure and cognitive function in these demographic groups.[31]

Gender-Specific Impacts

Another underexplored area is the potential gender-specific effects of transportation noise on health. Research has yet to fully investigate whether males and females respond differently to noise exposure, taking into account potential variations in physiological and behavioral responses. Frei et al. [89] suggest that physiological reactions are triggered by noise exposure independent of annoyance. In a gender specific analysis, they found evidence that the link between sleep quality and modeled noise exposure is stronger in men than in women.

Limitations of the Study

As with every study, certain limitations must be acknowledged. In this study, the reviewed literature predominantly focuses on Western European countries, particularly Germany, Switzerland, and the United Kingdom, and comparatively little attention is given to Central and Eastern Europe. This geographical imbalance may limit the generalizability of the findings, highlighting the need for future research to better capture regional differences in transport systems, urban structures, and population exposure across diverse European contexts more effectively. However, given that our search criteria focused on EU countries, the paucity of studies from Eastern Europe likely reflects the scarcity of research combining transport noise, health outcomes, and mitigation strategies in this region. As this review was a scoping review, no formal quality assessment or risk-of-bias appraisal was conducted. The aim was instead to map the scope of existing literature, classify the types of evidence available, summarize the range of reported health outcomes and mitigation strategies, and identify knowledge gaps. To facilitate interpretation, the studies were categorized according to their methodological design. However, the absence of a standardized quality appraisal means that the findings should be interpreted as a structured mapping of the literature rather than as a formal grading of the strength of the evidence. The identified studies were evaluated individually, and no meta-analysis of effect sizes was conducted.

CONCLUSION

The impact of noise pollution on various aspects of human life and health is pervasive. The recognition of noise as a significant environmental threat can be traced back to Nobel laureate Robert Koch’s foresight in 1910. Defining noise and noise pollution as disruptive and undesirable sounds that cause disturbance has paved the way for understanding their adverse effects on human well-being. With people all over the world being exposed to noise pollution from sources such as vehicular traffic, railways, airports, construction sites, industries and recreational activities, the health consequences are substantial, particularly in urban areas. This scoping review emphasizes the prevalence and health effects of environmental noise, focusing on road traffic and railway noise as the main sources in urban areas. The adverse health effects of noise pollution, including severe annoyance, sleep disturbance, reading impairment, hypertension, cardiovascular disease, and premature mortality, underscore the urgent need to address this issue on a global scale.

The WHO recognizes environmental noise as one of the greatest environmental threats to mental and physical health, attracting attention from the public and policymakers alike. The psychosocial stressor aspect of noise is emphasized, as it impacts subjective well-being and physical health by disrupting communication, concentration, relaxation, and sleep. This scoping review examined the impact of noise exposure on physical and mental health, assessing various mitigation strategies including the incorporation of green spaces, sound barriers, traffic organization, and rail treatments. The multifaceted effects of noise on annoyance, sleep disturbances, cognitive disruption, cardiovascular effects, and overall well-being are discussed in detail, drawing on numerous epidemiological studies, meta-analyses, and experimental investigations. Overall, the strongest evidence supports associations between transport noise exposure and cardiovascular disease, annoyance, and sleep disturbance. In contrast, findings for cancer, metabolic effects, and gender-specific differences are inconclusive and require further verification. These distinctions are important for guiding evidence-based public health interventions and identifying priority areas for future longitudinal and mechanistic research.

Several important gaps were identified. Further research is needed into the cumulative and combined effects of multimodal transport noise, including exposure to noise from roads, railways, and aircraft. More attention should also be given to vulnerable groups, such as children, older adults, and socioeconomically disadvantaged populations, as well as to gender-specific differences in exposure and health outcomes. Furthermore, future studies should move beyond self-reported annoyance and incorporate more objective health indicators, longitudinal designs, and integrated health impact assessments. Overall, this scoping review provides a structured overview of the current state of knowledge rather than a formal quality assessment or quantitative synthesis. By highlighting dominant research themes and unresolved gaps, the review can support future research agendas and inform the development of more targeted, evidence-based noise mitigation strategies and public health policies, and support future research agendas.

Availability of Data and Materials

All data and materials collected and used in this article are included within the article itself.

Author Contributions

Kourosh Haghbin: Conceptualization, Data curation, Formal Analysis, Investigation, Methodology, Software, Validation, Visualization, Writing—Original Draft, Writing—Review & Editing.

Bryce T. Lawrence: Conceptualization, Formal Analysis, Funding Acquisition, Investigation, Methodology, Project Administration, Resources, Software, Supervision, Validation, Visualization, Writing—Original Draft, Writing—Review & Editing.

Ethics Approval and Consent to Participate

No participants were included in this study, and thus, we do not require ethics approval. Since no participants were included, we do not have any informed consent to include.

Conflicts of Interest

The authors declare no conflict of interest.

Funding Statement

The work was funded by the German Research Foundation under grant GR 3658/1-1.