Blind Calibration of Environmental Acoustics Measurements Using Smartphones

Environmental noise control is a major health and social issue. Numerous environmental policies require local authorities to draw up noise maps to establish an inventory of the noise environment and then propose action plans to improve its quality. In general, these maps are produced using numerical simulations, which may not be sufficiently representative, for example, concerning the temporal dynamics of noise levels. Acoustic sensor measurements are also insufficient in terms of spatial coverage. More recently, an alternative approach has been proposed, consisting of using citizens as data producers by using smartphones as tools of geo-localized acoustic measurement. However, a lack of calibration of smartphones can generate a significant bias in the results obtained. Against the classical metrological principle that would aim to calibrate any sensor beforehand for physical measurement, some have proposed mass calibration procedures called "blind calibration". The method is based on the crossing of sensors in the same area at the same time, which are therefore supposed to observe the same phenomenon (i.e., measure the same value). The multiple crossings of a large number of sensors at the scale of a territory and the analysis of the relationships between sensors allow for the calibration of the set of sensors. In this article, we propose to adapt a blind calibration method to data from the NoiseCapture smartphone application. The method's behavior is then tested on NoiseCapture datasets for which information on the calibration values of some smartphones is already available.

Noise exposure and the risk of cancer: a comprehensive systematic review

The association between noise exposure and increased risk of cancer has received little attention in the field of research. Therefore, the goal of this study was to conduct a systematic review on the relationship between noise exposure and the incidence of cancer in humans. In this study, four electronic bibliographic databases including Scopus, PubMed, Web of Science, and Embase were systematically searched up to 21 April 2022. All types of noise exposure were considered, including environmental noise, occupational noise, and leisure or recreational noise. Furthermore, all types of cancers were studied, regardless of the organs involved. In total, 1836 articles were excluded on the basis of containing exclusion criteria or lacking inclusion criteria, leaving 19 articles retained for this study. Five of nine case-control studies showed a significant relationship between occupational or leisure noise exposure and acoustic neuroma. Moreover, four of five case-control and cohort studies indicated statistically significant relationships between environmental noise exposure and breast cancer. Of other cancer types, two case-control studies highlighted the risk of Hodgkin and non-Hodgkin lymphoma and two cohort studies identified an increased risk of colon cancer associated with environmental noise exposure. No relationship between road traffic and railway noise and the risk of prostate cancer was observed. In total, results showed that noise exposure, particularly prolonged and continuous exposure to loud noise, can lead to the incidence of some cancers. However, confirmation of this requires further epidemiological studies and exploration of the exact biological mechanism and pathway for these effects.

Impact of environmental noise exposure as an inducing factor on the prognosis of sudden sensorineural hearing loss: a retrospective case-control study

Objective

The study aimed to evaluate the clinical characteristics and prognostic factors associated with unilateral sudden sensorineural hearing loss (SSNHL) related to environmental noise exposure before its onset.

Methods

A total of 50 unilateral SSNHL patients exposed to environmental noise before onset (case group) and 924 unilateral SSNHL patients without any exposure to obvious inducing factors before onset (control group) were enrolled between January 2018 and October 2022. We retrospectively analyzed differences between both groups using the chi-square test, Fisher's exact tests, independent t-tests, and Mann-Whitney U-tests as appropriate before and after propensity score matching (PSM) based on sex, age, and initial pure-tone average (PTA). Prognostic factors for the case group were analyzed using univariate and multivariate logistic analyses between the effective and ineffective groups.

Results

Before PSM, significant differences were noted in age, sex, time to treatment, the proportion of combined diabetes mellitus, initial PTA, hearing gain, the incidence of vertigo or aural fulness, the rate of vestibular dysfunction or inner ear MRI abnormalities, the effective rate, the glucose and homocysteine levels, and the proportion of audiogram curve types (P < 0.05) between both groups. After PSM, compared to the control group, a longer time to treatment (Z= -3.02, P < 0.05), higher final PTA (Z= -2.39, P < 0.05), lower hearing gain (Z= -3.46, P < 0.05), lower rate of vestibular dysfunction (χ² = 55.1, P < 0.001), and lower effective rate (χ² = 4.87, P < 0.05) were observed in the case group. There was a significant difference between the audiogram curve types in both groups (χ² = 14.9, P < 0.05). Time to treatment (95% confidence interval: 0.692-0.965, P < 0.05) and final PTA (95% confidence interval: 0.921-0.998, P < 0.05) were associated with the clinical outcomes for the case group.

Conclusion

Unilateral SSNHL patients exposed to environmental noise triggers before onset showed a poorer effective rate and a lower rate of vestibular dysfunction than those who were not. The time to treatment and final PTA were associated with the prognosis of these patients.

Occupational and Environmental Noise Exposure and Extra-Auditory Effects on Humans: A Systematic Literature Review

Noise is a common harmful factor in our work and the environment. Most studies have investigated the auditory effects of noise exposure; however, few studies have focused on the extra-auditory effects of exposure to occupational or environmental noise. This study aimed to systematically review published studies on the extra-auditory effects of noise exposure. We reviewed literature from PubMed and Google Scholar databases up to July 2022, using the Patient, Intervention, Comparison, and Outcome criteria and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies that reported extra-auditory effects of occupational or environmental noise exposure. Studies were evaluated utilizing validated reporting tools (CONSORT, STROBE) appropriate to study design. A total of 263 articles were identified, of which 36 were finally selected and reviewed. Upon conducting a review of the articles, exposure to noise can elicit a variety of extra-auditory effects on humans. These effects include circulatory effects linked to higher risk of cardiovascular disease and decreased endothelial function, nervous system effects correlated with sleep disturbance, cognitive impairment, and mental health problems, immunological and endocrinal effects connected to increased physiological stress response and metabolic disorders, oncological and respiratory effects associated with an elevated risk of acoustic neuroma and respiratory disorders, gastrointestinal effects linked to an increased risk of gastric or duodenal ulcer, and obstetric effects connected to the risk of preterm birth. Our review suggests that there are numerous extra-auditory effects of noise exposure on human, and further investigations are needed to fully understand these effects.

The Impact of Aircraft Noise on the Cognitive Function of Elementary School Students in Korea

Background

This study evaluated the effects of chronic exposure to aircraft noise on the cognitive functions of Korean elementary school students attending an elementary school around a military airfield and clarified the relationship between noise exposure and cognitive functions.

Methods

Five schools with average weight equivalent continuous perceived noise levels (WECPNL) of ≥75 dB were selected from four regions in Korea. Each of these schools was matched with a non-exposed school. The Korean Intelligence Test Primary (KIT-P) was used to measure the scores of four subcategories and the intelligence quotient (IQ). The noise exposure groups were divided into high-exposure (WECPNL ≥ 80 dB) and medium-exposure (75 ≤ WECPNL < 80) groups. The period of exposure during the school year was collected. A linear mixed model, with matched pairs of schools, was used for statistical analysis.

Results

In the multivariable linear mixed model adjusted by possible confounders, the reasoning score was significantly lower in the high-exposure group of students than in the no-exposure group. Other scores and IQ were lower in the noise exposure groups, although these were not statistically significant. The duration of exposure did not show a significant relationship with cognitive functions.

Conclusion

Chronic exposure to noise from military airfields may influence the cognitive functions, thereby reducing the learning performance of Korean children.

The Role of Traffic Volume on Sound Pressure Level Reduction before and during COVID-19 Lockdown Measures-A Case Study in Bochum, Germany

During the SARS-CoV-2 pandemic, sound pressure levels (SPL) decreased because of lockdown measures all over the world. This study aims to describe SPL changes over varying lockdown measure timeframes and estimate the role of traffic on SPL variations. To account for different COVID-19 lockdown measures, the timeframe during the pandemic was segmented into four phases. To analyze the association between a-weighted decibels (dB(A)) and lockdown phases relative to the pre-lockdown timeframe, we calculated a linear mixed model, using 36,710 h of recording time. Regression coefficients depicting SPL changes were compared, while the model was subsequently adjusted for wind speed, rainfall, and traffic volume. The relative adjusted reduction of during pandemic phases to pre-pandemic levels ranged from -0.99 dB(A) (CI: -1.45; -0.53) to -0.25 dB(A) (CI: -0.96; 0.46). After controlling for traffic volume, we observed little to no reduction (-0.16 dB(A) (CI: -0.77; 0.45)) and even an increase of 0.75 dB(A) (CI: 0.18; 1.31) during the different lockdown phases. These results showcase the major role of traffic regarding the observed reduction. The findings can be useful in assessing measures to decrease noise pollution for necessary future population-based prevention.

Evolutionary loss of complexity in animal signals: cause and consequence

We identified hypotheses for the cause and consequences of the loss of complexity in animal signals and tested these using a genus of visually communicating lizards, the Southeast Asian Draco lizards. Males of some species have lost the headbob component from their display, which is otherwise central to the communication of this genus. These males instead display a large, colorful dewlap to defend territories and attract mates. This dewlap initially evolved to augment the headbob component of the display, but has become the exclusive system of communication. We tested whether the loss of headbobs was caused by relaxed selection, habitat-dependent constraints, or size-specific energetic constraints on display movement. We then examined whether the consequences of this loss have been mitigated by increased signaling effort or complexity in the color of the dewlap. It appears the increased cost of display movement resulting from the evolution of large body size might have contributed to the loss of headbobs and has been somewhat compensated for by the evolution of greater complexity in dewlap color. However, this evolutionary shift is unlikely to have maintained the complexity previously present in the communication system, resulting in an apparent detrimental loss of information potential.

Exploring the Joint Association of Road Traffic Noise and Air Quality with Hypertension Using QGIS

There is growing evidence linking exposure to air pollution and traffic noise with hypertension. The aim of this study was to examine the associations of registered hypertension cases and hypertension rate with exposure to air pollution and road noise. In this cross-sectional study, we linked the information from the NHS Scotland database of 776,579 hypertension patients' registrations and rates per 13.80 people at the Scottish NHS Board, HSCP, Cluster, and GP practice levels. Based on the geospatial attributes, the data on residential areas were added by modelling annual average air pollutant concentrations, including particulate matter (PM₁₀ and PM_2.5), nitrogen dioxide (NO₂), and road-traffic noise at different frequency components (Lden). The relationships between exposure to road noise, air pollution, and hypertension were examined using multiple regression and multivariate analysis. Traffic noise and air pollution at various frequency components positively and negatively predicted registered hypertension cases and hypertension rate. Based on the canonical loading technique, the variance explained by the canonical independent variable at a canonical correlation of 0.342 is 89%. There is a significant correlation between joint air pollution and noise at different frequency components and combined registered hypertension cases and hypertension rate. Exploring the combined effects of the two environmental exposures and the joint modelling of noise and air pollutants with hypertension in geospatial views provides an opportunity to integrate environmental and health data to support spatial assessment strategies in public and environmental health.

Development of Magnetocardiograph without Magnetically Shielded Room Using High-Detectivity TMR Sensors

A magnetocardiograph that enables the clear observation of heart magnetic field mappings without magnetically shielded rooms at room temperatures has been successfully manufactured. Compared to widespread electrocardiographs, magnetocardiographs commonly have a higher spatial resolution, which is expected to lead to early diagnoses of ischemic heart disease and high diagnostic accuracy of ventricular arrhythmia, which involves the risk of sudden death. However, as the conventional superconducting quantum interference device (SQUID) magnetocardiographs require large magnetically shielded rooms and huge running costs to cool the SQUID sensors, magnetocardiography is still unfamiliar technology. Here, in order to achieve the heart field detectivity of 1.0 pT without magnetically shielded rooms and enough magnetocardiography accuracy, we aimed to improve the detectivity of tunneling magnetoresistance (TMR) sensors and to decrease the environmental and sensor noises with a mathematical algorithm. The magnetic detectivity of the TMR sensors was confirmed to be 14.1 pT_rms on average in the frequency band between 0.2 and 100 Hz in uncooled states, thanks to the original multilayer structure and the innovative pattern of free layers. By constructing a sensor array using 288 TMR sensors and applying the mathematical magnetic shield technology of signal space separation (SSS), we confirmed that SSS reduces the environmental magnetic noise by -73 dB, which overtakes the general triple magnetically shielded rooms. Moreover, applying digital processing that combined the signal average of heart magnetic fields for one minute and the projection operation, we succeeded in reducing the sensor noise by about -23 dB. The heart magnetic field resolution measured on a subject in a laboratory in an office building was 0.99 pT_rms and obtained magnetocardiograms and current arrow maps as clear as the SQUID magnetocardiograph does in the QRS and ST segments. Upon utilizing its superior spatial resolution, this magnetocardiograph has the potential to be an important tool for the early diagnosis of ischemic heart disease and the risk management of sudden death triggered by ventricular arrhythmia.

Hypertension, a linchpin between environmental noise exposure and the development of cardiovascular disease?

Environmental noise exposure has been considered one of the most common hazards worldwide, especially in the workplace environment, and could produce a variety of health issues. Some epidemiological evidence supports the association between occupational noise exposition and a high risk for hypertension and cardiovascular diseases. Wang et al. has conducted an observational cross-sectional study using occupational data of 4746 workers, 32.4% were exposed to high occupational noise. These exposed individuals had a moderate increase in the risk for hypertension (adjusted odds ratio [OR], 1.30; 95% confidence interval [CI], 1.05-1.62). The subgroup analyses showed that the relationship between noise and hypertension prevalence was stronger in young participants (OR, 1.70; 95% CI, 1.21-2.40). Noise exposure activates the sympathetic and endocrine systems producing an increase in blood pressure and the changes in other biological risk factors. Moreover, a recently published study showed that oxidative stress and DNA damage were significantly higher in subjects exposed to noise. Emotional stress reactions and unconscious physiological stress could also be potential mechanisms for hypertension. Finally, physiological stress caused by noise exposure may also increase indulgence in unhealthy behaviors, such as smoking and alcohol consumption, and indirectly result in an increased risk of hypertension and cardiovascular diseases. Previously published studies showed relationships between environmental noise exposure (including road traffic, railway, and aircraft noises) and the development of hypertension and cardiovascular diseases. Thus, the study by Wang et al. emphasizes the importance of environmental control in the prevention of cardiovascular diseases, not only in the workplace but also outside it.

The Effects of Noise on Cognitive Performance and Helplessness in Childhood: A Review

Environmental noise affects our daily functioning in many ways, and the cognitive, motivational, and emotional effects of noise are intertwined. Our task performance under noisy conditions depends on our ability to cope with the noise and our cognitive resources. The process of (failed) coping may wear us out cognitively, lead to learned helplessness, and, consequently, alter the motivation to persist in a task. The direct effect of irrelevant sounds on cognitive functioning in children is relatively well-established, however, the research on the framework of learned helplessness is limited when it comes to children. Learned helplessness can give more insight into effects of environmental noise on learning and child development and how the effects of short-term and long-term exposure interact. A systematic literature review is performed to assess to what extent the current evidence addresses the (interaction) effects of the sound environment on cognition and learned helplessness as measured by motivation in children and young adults up to the age of 21. The search resulted in 8 included papers that addressed both cognition and learned helplessness in their research. The included papers study children between 8-13 years old and show evidence for a relation between environmental noise, cognition, and helplessness individually, but none study a possible interaction. Based on the individual study designs, it could be hypothesized that cognitive fatigue may play a role in the interaction. Studies that conducted motivation tasks after cognitive tasks found stronger effects than those that conducted tasks in a random order. More research is needed using the same methods in different age groups to further assess the interaction between cognition and learned helplessness in relation to the sound environment.

Exploring the Combined Association between Road Traffic Noise and Air Quality Using QGIS

There is mounting evidence that exposure to air pollution and noise from transportation are linked to the risk of hypertension. Most studies have only looked at relationships between single exposures. To examine links between combined exposure to road traffic, air pollution, and road noise. A Casella CEL-63x instrument was used to monitor traffic noise on a number of locations in residential streets in Glasgow, UK during peak traffic hours. The spatial numerical modelling capability of Quantum GIS (abbreviated QGIS) was used to analyse the combined association of noise and air pollution. Based on geospatial mapping, data on residential environmental exposure was added using annual average air pollutant concentrations from local air quality monitoring network, including particulate matter (PM₁₀ and PM_2.5), nitrogen dioxide (NO₂), and road-traffic noise measurements at different component frequencies (Lden). The combined relationships between air pollution and traffic noise at different component frequencies were examined. Based on Moran I autocorrelation, geographically close values of a variable on a map typically have comparable values when there is a positive spatial autocorrelation. This means clustering on the map was influenced significantly by NO₂, PM₁₀ and PM_2.5, and Lden at the majority of monitoring locations. Studies that only consider one of these two related exposures may exaggerate the impact of the individual exposure while underestimating the combined impact of the two environmental exposures.

Environmental Noise Exposure and Sleep Habits among Children in a Cohort from Northern Spain

Environmental noise is considered the second most serious environmental risk factor in Europe. However, little evidence exists regarding its impact on health and sleep in children, and the results are inconclusive. In this study, we aim to analyse the effect of environmental noise exposure on 11-year-old children's sleep habits. Data were collected from 377 participants in the INMA-Gipuzkoa (INfancia y Medio Ambiente) cohort project using both parent-reported and actigraphic sleep measures. The results revealed that 60% of children have a day-evening-night environmental noise exposure (L_den) of above 55 dB, which is defined as a "high noise level". No differences in noise exposure were observed between different socioeconomic groups. However, no effect of environmental noise was found on sleep variables. The paper highlights the importance of studying how environmental noise may affect children's sleep.

Cardiovascular consequences of aircraft noise exposure

The results from epidemiological studies suggest that environmental noise including aircraft, railway, road traffic, wind turbine, and leisure-related noise is a growing public health concern. According to the WHO, at least 100 million people in the European Union are affected by traffic noise levels above the WHO-recommended thresholds. Environmental noise can adversely affect physical and mental health, as well as wellbeing. Chronic low-level noise exposure typical for most environmental sources is associated with psychophysiological stress causing non-auditory or indirect noise effects leading ultimately to cardiovascular diseases. Among all environmental noise sources, aircraft noise is considered the most annoying, and its leading mechanism of action is autonomic system activation such as increases in heart rate and blood pressure. Previously, we observed that long-term exposure to aircraft noise was associated with increased diastolic blood pressure, arterial stiffness (as assessed by pulse wave velocity), and impaired left ventricular diastolic function. All mentioned above effects are early, subclinical, and potentially reversible changes which preceded late noise effects in the cardiovascular system, that is, established cardiovascular diseases such as myocardial infarction, stroke, and heart failure. However, even a short-term reduction in aircraft noise exposure as observed during the COVID-19 lockdown may reverse these negative effects on arterial stiffness and blood pressure and may decrease the prevalence of insomnia. In this review, we aimed to critically discuss our obtained results considering recent studies on the influence of aircraft noise (and other traffic noises) on cardiovascular diseases in the context of the WHO Environmental Noise Guidelines for the European Region.

Noise Indicators Relating to Non-Auditory Health Effects in Children-A Systematic Literature Review

A systematic literature review was conducted to investigate which objective noise indicators related to various noise sources (i.e., aircraft, road-traffic, and ambient noise) are the best predictors of non-auditory health-effects in children. These relationships are discussed via a conceptual framework, taking into account main parameters such as the type of noise source, the exposure locations and their environments, the type of noise indicators, the children's mediating factors, and the type of non-auditory health effects. In terms of the procedure, four literature databases were screened and data was extracted on study design, types of noise sources, assessment method, health-based outcomes and confounders, as well as their associations. The quality of the studies was also assessed. The inclusion criteria focused on both indoor and outdoor environments in educational buildings and dwellings, considering that children spend most of their time there. From the 3337 uniquely collected articles, 36 articles were included in this review based on the defined inclusion and exclusion criteria. From the included literature, it was seen that noise exposure, assessed by energetic indicators, has significant associations with non-auditory health effects: psychophysiological, cognitive development, mental health and sleep effects. Percentile and event-based indicators provided significant associations to cognitive performance tasks and well-being dimension aspects.

Using a Clustering Method to Detect Spatial Events in a Smartphone-Based Crowd-Sourced Database for Environmental Noise Assessment

Noise has become a very notable source of pollution with major impacts on health, especially in urban areas. To reduce these impacts, proper evaluation of noise is very important, for example by using noise mapping tools. The Noise-Planet project seeks to develop such tools in an open science platform, with a key open-source smartphone tool "NoiseCapture" that allows users to measure and share the noise environment as an alternative to classical methods, such as simulation tools and noise observatories, which have limitations. As an alternative solution, smartphones can be used to create a low-cost network of sensors to collect the necessary data to generate a noise map. Nevertheless, this data may suffer from problems, such as a lack of calibration or a bad location, which lowers its quality. Therefore, quality control is very crucial to enhance the data analysis and the relevance of the noise maps. Most quality control methods require a reference database to train the models. In the context of NC, this reference data can be produced during specifically organized events (NC party), during which contributors are specifically trained to collect measurements. Nevertheless, these data are not sufficient in number to create a big enough reference database, and it is still necessary to complete them. Other communities around the world use NC, and one may want to integrate the data they collected into the learning database. In order to achieve this, one must detect these data within the mass of available data. As these events are generally characterized by a higher density of measurements in space and time, in this paper we propose to apply a classical clustering method, called DBSCAN, to identify them in the NC database. We first tested this method on the existing NC party, then applied it on a global scale. Depending on the DBSCAN parameters, many clusters are thus detected, with different typologies.

Statistical Pass-By for Unattended Road Traffic Noise Measurement in an Urban Environment

Low-noise surfaces have become a common mitigation action in the last decade, so much so that different methods for feature extraction have been established to evaluate their efficacy. Among these, the Close Proximity Index (CPX) evaluates the noise emissions by means of multiple runs at different speeds performed with a vehicle equipped with a reference tire and with acoustic sensors close to the wheel. However, signals acquired with CPX make it source oriented, and the analysis does not consider the real traffic flow of the studied site for a receiver-oriented approach. These aspects are remedied by Statistical Pass-By (SPB), a method based on sensor feature extraction with live detection of events; noise and speed acquisitions are performed at the roadside in real case scenarios. Unfortunately, the specific SPB requirements for its measurement setup do not allow an evaluation in urban context unless a special setup is used, but this may alter the acoustical context in which the measurement was performed. The present paper illustrates the testing and validation of a method named Urban Pass-By (U-SPB), developed during the LIFE NEREiDE project. U-SPB originates from standard SPB, exploits unattended measurements and develops an in-lab feature detection and extraction procedure. The U-SPB extends the evaluation in terms of before/after data comparison of the efficiency of low-noise laying in an urban context while combining the estimation of long-term noise levels and traffic parameters for other environmental noise purposes, such as noise mapping and action planning.

The day-to-day impact of nighttime noise disturbances on college students' psychological functioning

ObjectiveTo understand environmental predictors (i.e., nighttime noise disturbance) of sleep health (i.e., restedness) in residential college students and its potential mental health consequences, this study examined daily variation in restedness upon awakening as a potential mediator between nightly environmental noise disturbances and daily fluctuations in depressive and anxiety symptoms. Participants: The sample was comprised of 283 college students (M_age = 19.9, SD = 1.9; 79% female). Methods: Multilevel structural equation modeling was conducted based on an initial self-report, online questionnaire and an online 7-day daily sleep (morning) and mood (evening) diary. Results: Daily fluctuations in college students' reports of restedness (morning diary) mediated the association between the nighttime presence of noise disturbances (morning diary) and depressive and anxiety symptoms (evening diary). Conclusions: Given the high prevalence of mental health problems in college students, creating more conducive sleep environments may help to prevent depressive and anxiety symptoms in this population.

Relationships between long-term residential exposure to total environmental noise and stroke incidence

BACKGROUND

Noise has been related to several cardiovascular diseases (CVDs) such as coronary heart disease and to their risk factors such as hypertension, but associations with stroke remain under-researched, even if CVD likely share similar pathophysiologic mechanisms.

AIM

The objective of the study was to examine the association between long-term residential exposure to total environmental noise and stroke incidence in Montreal, Canada.

MATERIALS AND METHODS

We created an open cohort of adults aged ≥45years, free of stroke before entering the cohort for the years 2000 to 2014 with health administrative data. Residential total environmental noise levels were estimated with land use regression (LUR) models. Incident stroke was based on hospital admissions. Cox hazard models with age as the time axis and time-varying exposures were used to estimate associations, which were adjusted for material deprivation, year, nitrogen dioxide, stratified for sex, and indirectly adjusted for smoking.

RESULTS

There were 9,072,492 person-years of follow-up with 47% men; 26,741 developed stroke (21,402 ischemic; 4947 hemorrhagic; 392 had both). LUR total noise level acoustic equivalent for 24 hours (LAeq24h) ranged 44 to 79 dBA. The adjusted hazard ratio (HR) for stroke (all types), for a 10-dBA increase in LAeq24h, was 1.06 [95% confidence interval (CI): 1.03-1.09]. The LAeq24h was associated with ischemic (HR per 10 dBA: 1.08; 95% CI: 1.04-1.12) but not hemorrhagic stroke (HR per 10 dBA: 0.97; 95% CI: 0.90-1.04).

CONCLUSION

The results suggest that total environmental noise is associated with incident stroke, which is consistent with studies on transportation noise and other CVD.

Pre-Sleep Cognitive Arousal Is Negatively Associated with Sleep Misperception in Healthy Sleepers during Habitual Environmental Noise Exposure: An Actigraphy Study

Specific noises (e.g., traffic or wind turbines) can disrupt sleep and potentially cause a mismatch between subjective sleep and objective sleep (i.e., “sleep misperception”). Some individuals are likely to be more vulnerable than others to noise-related sleep disturbances, potentially as a result of increased pre-sleep cognitive arousal. The aim of the present study was to examine the relationships between pre-sleep cognitive arousal and sleep misperception. Sixteen healthy sleepers participated in this naturalistic, observational study. Three nights of sleep were measured using actigraphy, and each 15-s epoch was classified as sleep or wake. Bedside noise was recorded, and each 15-s segment was classified as containing noise or no noise and matched to actigraphy. Participants completed measures of habitual pre-sleep cognitive and somatic arousal and noise sensitivity. Pre-sleep cognitive and somatic arousal levels were negatively associated with subjective−objective total sleep time discrepancy (p < 0.01). There was an association between sleep/wake and noise presence/absence in the first and last 90 min of sleep (p < 0.001). These results indicate that higher levels of habitual pre-sleep arousal are associated with a greater degree of sleep misperception, and even in healthy sleepers, objective sleep is vulnerable to habitual bedside noise.

Impact of Noise Exposure on Risk of Developing Stress-Related Health Effects Related to the Cardiovascular System: A Systematic Review and Meta-Analysis

Background

: Exposure to acute noise can cause an increase in biological stress reactions, which provides biological plausibility for a potential association between sustained noise exposure and stress-related health effects. However, the certainty in the evidence for an association between exposures to noise on short- and long-term biomarkers of stress has not been widely explored. The objective of this review was to evaluate the strength of evidence between noise exposure and changes in the biological parameters known to contribute to the development of stress-related adverse cardiovascular responses.

Materials and Methods

This systematic review comprises English language comparative studies available in PubMed, Cochrane Central, EMBASE, and CINAHL databases from January 1, 1980 to December 29, 2021. Where possible, random-effects meta-analyses were used to examine the effect of noise exposure from various sources on stress-related cardiovascular biomarkers. The risk of bias of individual studies was assessed using the risk of bias of nonrandomized studies of exposures instrument. The certainty of the body of evidence for each outcome was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach.

Results

: The search identified 133 primary studies reporting on blood pressure, hypertension, heart rate, cardiac arrhythmia, vascular resistance, and cardiac output. Meta-analyses of blood pressure, hypertension, and heart rate suggested there may be signals of increased risk in response to a higher noise threshold or incrementally higher levels of noise. Across all outcomes, the certainty of the evidence was very low due to concerns with the risk of bias, inconsistency across exposure sources, populations, and studies and imprecision in the estimates of effects.

Conclusions

: This review identifies that exposure to higher levels of noise may increase the risk of some short- and long-term cardiovascular events; however, the certainty of the evidence was very low. This likely represents the inability to compare across the totality of the evidence for each outcome, underscoring the value of continued research in this area. Findings from this review may be used to inform policies of noise reduction or mitigation interventions.

A Noise Control Method Using Adaptive Adjustable Parametric Array Loudspeaker to Eliminate Environmental Noise in Real Time

Long-term exposure to environmental noise is dangerous to human health. Therefore, there is an urgent need to suppress or eliminate environmental noise. Due to the limitation of environmental space, the use of reverse sound waves emitted by loudspeakers for noise elimination has been widely used in noise control. However, because of the omni-directionality of sound propagation, a traditional voice coil loudspeaker (VCL) is used as a secondary source (emission reverse sound wave). It is easy to increase the sound pressure in non-target areas and form significant acoustic feedback to the reference source. Therefore, we propose an online secondary path modeling method using an adjustable parametric array loudspeaker (PAL) based on ultrasounds to eliminate environmental noise in real time. According to the different distance of the target, the size of the PAL is adjusted adaptively to realize the noise control of different long-distance targets. The distribution of quiet areas is discussed. The experimental results showed that a PAL as a secondary source had the same noise reduction effect as a traditional VCL, but it had longer propagation distance, smaller sound feedback and a more regular and controllable distribution of quiet areas. These research findings have great potential for improving environmental noise and creating a quiet environment.

Comparison of Road Noise Policies across Australia, Europe, and North America

Developing innovative noise policies that build on international best practices is difficult when policies around the world differ along many dimensions, ranging from different sources covered to different levels of governance involved. This is particularly critical in the context of road traffic, identified as one of the main culprits leading to noise-associated complaints and health issues. In this article, we document the wide range of specifications observed in road traffic policies and propose a methodology to compare noise limits across noise policies. First, we present the responsibilities of administrative governments according to the scope (e.g., emission vs. exposure). Second, we compare noise limits by scope and geographic areas by separating acoustic indicators (overall and event indicators). Third, we convert overall outdoor noise limits into a common basis using the method described by Brink and his associates (2018) and compare them with the World Health Organization (WHO)'s recommendations (2018). Finally, measurement protocols are also compared across outdoor noise policies. This paper shows that road noise is managed at several administrative levels using approaches that are either centralized or decentralized. We also observed disparities in the associated noise limits across geographic areas. The converted outdoor noise limits generally exceeded the WHO's recommendations (2018). Finally, this paper outlines how outdoor measurement protocols vary across geographic areas. However, similarities were identified between state and provincial noise policies within the same country.

Quantification of Sound Exposure from Wind Turbines in France

The WHO guidelines on environmental noise highlight that evidence on the health effects of wind turbine sound levels is either non-existent or of poor quality. In this context, a feasibility study was conducted in France in 2017. The objective was to suggest a methodology for calculating wind turbine sound levels in order to quantify the number of windfarms' residents exposed to this sound. Based on a literature review, the Harmonoise model was selected for sound exposure calculation. It was validated by quantifying its uncertainties, and finally used to estimate the population exposed to wind turbine sound in metropolitan France. Compared to other environmental noise sources (e.g., transportation), sound exposure is very moderate, with more than 80% of the exposed people exposed to sound levels below 40 dBA. The total number of people exposed to more than 30 dBA is about 686,000 and 722,000 people for typical daytime and night-time meteorological conditions respectively, i.e., about 1% of the French population in 2017. These results represent the first ever assessment of sound exposure from wind turbines at the scale of the entire metropolitan France.

The effect of wind turbine noise on polysomnographically-measured and self-reported sleep latency in wind turbine noise naïve participants

STUDY OBJECTIVES

Wind turbine noise exposure could potentially interfere with the initiation of sleep. However, effects on objectively assessed sleep latency are largely unknown. This study sought to assess the impact of wind turbine noise on polysomnographically-measured and sleep diary-determined sleep latency compared to control background noise alone in healthy good sleepers without habitual prior wind turbine noise exposure.

METHODS

Twenty-three wind turbine noise naïve urban residents (mean±standard deviation age: 21.7±2.1 years, range 18-29, 13 females) attended the sleep laboratory for two polysomnography studies, one week apart. Participants were blind to noise conditions and only informed that they may or may not hear noise during each night. During the sleep onset period, participants were exposed to counterbalanced nights of wind turbine noise at 33 dB(A), the upper end of expected indoor values; or background noise alone as the control condition (23 dB(A)).

RESULTS

Linear mixed model analysis revealed no differences in log10 normalized objective or subjective sleep latency between the wind turbine noise versus control nights (median [interquartile range] objective 16.5 [11.0 to 18.5] versus 16.5 [10.5 to 29.0] minutes, p = 0.401; subjective 20.0 [15.0 to 25.0] versus 15.0 [10.0 to 30.0] minutes, p = 0.907).

CONCLUSIONS

Although undetected small effects cannot be ruled out, these results do not support that wind turbine noise extends sleep latency in young urban dwelling individuals without prior wind turbine noise exposure.

Associations between Personal Attitudes towards COVID-19 and Public Space Soundscape Assessment: An Example from Antwerp, Belgium

The COVID-19 pandemic, and the lockdown events and policies that followed, led to significant changes in the built environment and how it is experienced by people and communities. Among those, variations in the acoustic environments were some of the most noticeable in cities. This study investigated the relationships between the perception of the acoustic environment (i.e., soundscape) and different personal factors such as attitudes towards the pandemic and noise sensitivity, by performing a survey with 109 participants in an urban green public space in Antwerp (Belgium), shortly after most restrictions issued by the government were lifted in September 2020 when the first contamination wave ended. While preliminary in nature, the results of this data collection campaign show that people actively changing their behaviors (using less public transport or cycling more) assessed the soundscapes as less vibrant/exciting. People who were more concerned about the pandemic tended to notice more natural sounds and noise from traffic on nearby local roads. This same subset also put a bigger importance on the environmental quality of the public space than in the pre-pandemic period. Noise sensitivity also played a role, as an association was found between more-than-average noise sensitive persons and those more worried regarding the pandemic. Overall, the findings of this study confirm that at least part of the people have started to perceive the public space, including its soundscape, differently since the start of the pandemic.

The Negative Impact of Noise on Adolescents' Executive Function: An Online Study in the Context of Home-Learning During a Pandemic

UNICEF estimates that 1.6 billion children across the world have had their education impacted by COVID-19 and have attempted to continue their learning at home. With ample evidence showing a negative impact of noise on academic achievement within schools, the current pre-registered study set out to determine what aspects of the home environment might be affecting these students. Adolescents aged 11-18 took part online, with 129 adolescents included after passing a headphone screening task. They filled out a sociodemographic questionnaire, followed by a home environment and noise questionnaire. Participants then completed three executive function tasks (the Flanker, the Backward Digit Span, and the Wisconsin Card Sorting Test) while listening to a soundtrack of either white noise or home-like environmental noise. For purposes of analysis, based on the noise questionnaire, participants were separated into quieter and noisier homes. Results revealed that measures of the home environment significantly correlated with individual perceptions of noise and task performance. In particular, adolescents coming from noisier homes were more likely to report that they studied in a noisy room and that they were annoyed by noise when studying. In terms of noise and task performance, the Flanker task revealed that while older adolescents were more efficient overall than their younger peers, those older adolescents from noisier homes seemed to lose this advantage. Additionally, reaction times for younger adolescents from noisier homes were less impacted by accuracy compared to their peers from quieter homes, though there was no difference for the older adolescents. This evidence suggests that higher in-home noise levels lead to higher rates of annoyance and may be hindering home-learning, with both younger and older adolescents being impacted. Furthermore, the long-term effect of in-home noise on adolescent executive function task performance indicates that these findings transcend the pandemic and would influence in-school learning. Limitations and advantages of online adolescent research without researcher supervision are discussed, including sociodemographics and adapting tasks.

Sex/Gender-Differences in the Health Effects of Environmental Noise Exposure on Hypertension and Ischemic Heart Disease-A Systematic Review

Previous studies have demonstrated cardiovascular health effects of environmental noise exposure, partly showing different effect estimates for males and females. This cannot be explained by biological differences between males and females alone. It is assumed that health outcomes and exposure patterns also depend on gender, determined by social, economic, and cultural factors in society. This systematic review evaluated the current state of how sex/gender is integrated in studies on environmental noise associated with hypertension, blood pressure, and ischemic heart diseases. A systematic literature search was conducted in three different databases, identifying thirty studies published between 1 January 2000 and 2 February 2020. Effects varied, with no consistent findings for both males and females. All studies used a binary operationalization of sex/gender, assuming static differences between males and females. The differentiation between biological and social dimensions of sex/gender was not present in any of the studies and the terms “sex” and “gender” were used interchangeably. However, biological and social dimensions of sex/gender were unconsciously taken up in the discussion of the results. Integrating sex/gender-theoretical concepts into future studies offers great potential to increase the validity of research findings, thus making them more useful for prevention efforts, health promotion, and health care.

The Burden of Disease Due to Road Traffic Noise in Hesse, Germany

Road-traffic-noise exposition is widespread in Germany and can have harmful health effects. As guidance for informed decision-making, we estimated the environmental burden of disease attributable to road-traffic noise in Hesse, Germany as disability-adjusted life-years (DALYs). Using detailed road-traffic-noise exposure data provided by the Hessian Agency for Nature Conservation, Environment, and Geology (HLNUG), we calculated the DALYs due to road-traffic noise > 40 dB(A) L_24h (unweighted average 24 h noise level) and other noise metrics for endpoints with known dose-response functions and evidence in the literature (NORAH-study on disease risks and WHO reviews): cardiovascular disease, depressive disorders, road-traffic annoyance, and sleep disturbance. We calculated the population-attributable fractions (PAF) for road-noise-related cardiovascular disease (hypertensive heart disease, ischemic heart disease, and stroke) and depressive disorders in the population using published relative risk estimates. We multiplied the PAFs with the Hessian proportion of the 2015 WHO DALY estimates for Germany in people aged ≥ 40 years. For high annoyance and high sleep disturbance, we used published dose-response functions to determine the burden for residents of all ages. For Hesse, we found a total of 26,501 DALYs attributable to road-traffic noise or 435 DALY per 100,000 persons for the reference year, 2015. Further, we estimated that a hypothetic uniform road-traffic-noise reduction of 3 dB would prevent 23% of this burden of disease.

Effect of Environmental Noise, Distance and Warning Sound on Pedestrians' Auditory Detectability of Electric Vehicles

With developments in science and technology, the number of electric vehicles will increase, and they will even replace ICE vehicles. Thus, perceiving the presence of approaching electric vehicles on the road has become an important issue. In this study, the auditory detectability of the electric vehicle warning sound at different volumes, distances, and environmental noise levels was investigated. To this end, the detection rate was recorded in experiments with three environmental noise levels (50, 60, and 70 dBA), two sound pressure levels (SPLs) of the warning sound (46 and 51 dBA), three frequency combinations of the warning sound (5000, 2500, 1250, and 630 Hz for high frequencies; 2500, 1250, 630, and 315 Hz for medium frequencies; and 1250, 630, 315, and 160 Hz for low frequencies), and five distances (2, 4, 6, 8, and 10 m). The main results showed that the detection rate at 51 dBA was significantly higher than that at 46 dBA under a high-frequency warning sound; however, the detection rates were similar under medium- and low-frequency warning sounds. The participants’ rates of detection for warning sounds were less than 20% under all experimental conditions, and a high-frequency warning sound was not affected by environmental noise. With regard to distances, no significant effects were observed between the distances and the detection rate at any of the three frequencies. In addition, auditory thresholds based on high-, medium-, and low-frequency warning sounds were found through logistic regression analysis results. The results of this study can be used as a reference for the future design of warning sounds.

Effects of Exposure to Road, Railway, Airport and Recreational Noise on Blood Pressure and Hypertension

Noise is one of the most diffused environmental stressors affecting modern life. As such, the scientific community is committed to studying the main emission and transmission mechanisms aiming at reducing citizens' exposure, but is also actively studying the effects that noise has on health. However, scientific literature lacks data on multiple sources of noise and cardiovascular outcomes. The present cross-sectional study aims to evaluate the impact that different types of noise source (road, railway, airport and recreational) in an urban context have on blood pressure variations and hypertension. 517 citizens of Pisa, Italy, were subjected to a structured questionnaire and five measures of blood pressure in one day. Participants were living in the same building for at least 5 years, were aged from 37 to 72 years old and were exposed to one or more noise sources among air traffic, road traffic, railway and recreational noise. Logistic and multivariate linear regression models have been applied in order to assess the association between exposures and health outcomes. The analyses showed that prevalence of high levels of diastolic blood pressure (DBP) is consistent with an increase of 5 dB (A) of night-time noise (β = 0.50 95% CI: 0.18-0.81). Furthermore, increased DBP is also positively associated with more noise sensitive subjects, older than 65 years old, without domestic noise protection, or who never close windows. Among the various noise sources, railway noise was found to be the most associated with DBP (β = 0.68; 95% CI: -1.36, 2.72). The obtained relation between DBP and night-time noise levels reinforces current knowledge.

A Smartphone-Based Crowd-Sourced Database for Environmental Noise Assessment

Noise is a major source of pollution with a strong impact on health. Noise assessment is therefore a very important issue to reduce its impact on humans. To overcome the limitations of the classical method of noise assessment (such as simulation tools or noise observatories), alternative approaches have been developed, among which is collaborative noise measurement via a smartphone. Following this approach, the NoiseCapture application was proposed, in an open science framework, providing free access to a considerable amount of information and offering interesting perspectives of spatial and temporal noise analysis for the scientific community. After more than 3 years of operation, the amount of collected data is considerable. Its exploitation for a sound environment analysis, however, requires one to consider the intrinsic limits of each collected information, defined, for example, by the very nature of the data, the measurement protocol, the technical performance of the smartphone, the absence of calibration, the presence of anomalies in the collected data, etc. The purpose of this article is thus to provide enough information, in terms of quality, consistency, and completeness of the data, so that everyone can exploit the database, in full control.

Fish Avoid Visually Noisy Environments Where Prey Targeting Is Reduced

AbstractThe environment contains different forms of ecological noise that can reduce the ability of animals to detect information. Here, we ask whether animals adapt their behavior to either exploit or avoid areas of their environment with increased dynamic visual noise. Three-spined sticklebacks (Gasterosteus aculeatus) were immersed in environments with a simulated form of naturally occurring visual noise-moving light bands that form on underwater substrates caused by the refraction of light through surface waves. We tested whether this form of visual noise affected fish's habitat selection, movements, and prey-targeting behavior. Fish avoided areas of the environment with increased visual noise and achieved this by increasing their activity as a function of the locally perceived noise level. Fish were less likely to respond to virtual prey in environments with increased visual noise, highlighting a potential impact that visual noise has on their perceptual abilities. Fish did not increase or decrease their refuge use in environments with increased visual noise, providing no evidence that visual noise increased either exploratory or risk-aversive behavior. Our results indicate that animals can use simple behavioral strategies to avoid visually noisy environments, thereby mitigating the impacts that these environments appear to have on their perceptual abilities.

Subjective Evaluation on the Annoyance of Environmental Noise Containing Low-Frequency Tonal Components

Recently in Japan, noises from wind turbines and domestic use heat sources sometimes cause an increase in noise annoyance owing to low-frequency tonal components. The purpose of this study was to investigate the effects of the tonal components on the annoyance of the environmental noise. The authors conducted an auditory test in the laboratory to evaluate the annoyance of tonal noise using a seven-step rating method. The stimuli were composed of a broadband noise modeling of the environmental noise (25, 30, and 35 dB) and a low-frequency tonal component. With the tonal component added to the broadband noise, the frequency and tonal audibility were varied to 40, 50, 100, 200, and 400 Hz and 0, 3, 6, 9, and 12 dB, respectively. The amount of increase in annoyance owing to the addition of the tonal component was quantitatively evaluated as a tonal adjustment by comparing it with broadband noise. As a result, tonal adjustment ranged from 0 to 7 dB, and the higher the tonal frequency, the larger the value. For the test background noise level, the lower the background noise level of the test sound, the greater the value. This trend suggests that the influence of tonal components on subjective impressions is stronger in quiet environments such as residential areas. This result may provide a basis for the evaluation method, which varies the penalty in the noise evaluation according to the frequency of the pure tones and the noise level.

Selected Approaches to the Assessment of Environmental Noise from Railways in Urban Areas

Rail transport is the second most important way of transporting people and freights by land in the European Union. Rail noise affects around 12 million people in the European Union during the day and around 9 million at night. There are two possible ways to assess environmental noise: noise measurement in situ and prediction using mathematical models. The aim of the work is based on the performed measurements and selected noise predictions to evaluate the accuracy of the prediction models and assess their sensitivity to various aspects. Two measuring points in the Banská Bystrica Self-Governing Region, within Slovakia, were selected for measurement, which is characterized by increased mobility of the population. For prediction, the two methodologies were selected (Schall 03 and Methodical instructions for the calculation of sound pressure level from transport). The results show that the Schall 03 method is sensitive to the measurement location (the value reaches half of the significance level) and to the location–period interaction. The second prediction method is sensitive to systematic error (absolute term) and, such as Schall 03, to the location–period interaction. This method systematically overestimates the results. Results showed greater accuracy of both prediction models compared to the measured noise values than the results of the authors in other countries and conditions.

Environmental noise, its types and effects on health

Noise can be defined as an undesirable sound that pollutes the environment. If noise is continuous and exceeds certain levels, negative effects on health can be observed. In recent years, the impact of environmental noise (road traffic noise, railway traffic noise, air traffic noise and industrial noise) on human health has come under increasingly intense scrutiny. Noise can cause a number of negative effects on health that directly or indirectly affect humans. The occurrence of some certain and harmful health effects drives the onset of others and may contribute to the development of various diseases. Health is not only a state of physical well-being, but also mental well-being. Mental health primarily depends on the quality of life, which can be affected by various environmental factors, such as noise. An important aspect of fighting noise is the most effective protection of the population by avoiding sources of noise and reducing it. This can be achieved by introducing new technical solutions and new technologies, including devices that generate less noise. Another important measure is educating the society and influencing the change of individual and collective behavior, which may contribute to reducing the harmful factor, which is noise in human life, and minimize the resulting negative effects on health.

Revisiting the Concept of Quietness in the Urban Environment-Towards Ecosystems' Health and Human Well-Being

There is plenty of proof that environmental noise is a major pollutant in the urban environment. Several approaches were successfully applied for its calculation, visualization, prediction and mitigation. The goal of all strategy plans regards its reduction and the creation of quietness. This study aims to revisit the concept of quietness in the urban environment and attempts to portray a new understanding of the specific phenomena. "Quietness" as a term retains an ambiguity, and so far, it can be described as the lack of something, meaning the lack of noise that is portrayed by means of intensity. Several studies describe quietness as the combination of perceptual soundscape elements and contextual factors that can be quantified, combined, weighed and used as indicators of healthy soundscapes. In this research, the focus is on setting aside all indicators, either measuring the intensity or contextual ones and use solely quantifiable metrics regarding the acoustic environment, thus introducing a new composite index called the composite urban quietness index (CUQI). After testing the CUQI, in order to verify the results of previous research regarding the identification of quiet Areas in the city of Mytilene (Lesbos Island, Greece), the study concludes that CUQI is efficiently functioning even in this early stage of development.

Life in fluctuating environments

Variability in the environment defines the structure and dynamics of all living systems, from organisms to ecosystems. Species have evolved traits and strategies that allow them to detect, exploit and predict the changing environment. These traits allow organisms to maintain steady internal conditions required for physiological functioning through feedback mechanisms that allow internal conditions to remain at or near a set-point despite a fluctuating environment. In addition to feedback, many organisms have evolved feedforward processes, which allow them to adjust in anticipation of an expected future state of the environment. Here we provide a framework describing how feedback and feedforward mechanisms operating within organisms can generate effects across scales of organization, and how they allow living systems to persist in fluctuating environments. Daily, seasonal and multi-year cycles provide cues that organisms use to anticipate changes in physiologically relevant environmental conditions. Using feedforward mechanisms, organisms can exploit correlations in environmental variables to prepare for anticipated future changes. Strategies to obtain, store and act on information about the conditional nature of future events are advantageous and are evidenced in widespread phenotypes such as circadian clocks, social behaviour, diapause and migrations. Humans are altering the ways in which the environment fluctuates, causing correlations between environmental variables to become decoupled, decreasing the reliability of cues. Human-induced environmental change is also altering sensory environments and the ability of organisms to detect cues. Recognizing that living systems combine feedback and feedforward processes is essential to understanding their responses to current and future regimes of environmental fluctuations.

This article is part of the theme issue ‘Integrative research perspectives on marine conservation’.

Long-term exposure to low-intensity environmental noise aggravates age-related hearing loss via disruption of cochlear ribbon synapses

Noise pollution is a major public hazard. Previous studies have shown that environmental noise affects the reorganization of the auditory cortex and leads to behavioral abnormality; however, the effects of long-term environmental noise exposure on the inner ear and hearing remain to be elucidated. In this study, we simulated environmental noise with a long-term 70 dB sound pressure level "white" noise, observed its effect on the inner ears of C57BL/6J mice, and developed an in vitro model for mechanistic studies. We found that environmental noise increased the hearing threshold, decreased the auditory response amplitude, and aggravated the range and extent of age-related hearing loss (ARHL), especially in the intermediate frequency band in mice. Cochlear ribbon synapse is the primary site of inner ear injury caused by environmental noise. We also verified, through an in vitro simulation of the excitatory toxicity of glutamate and aging effects, that the activation of NLRP3 inflammasome plays a vital role in the cochlear ribbon synaptic damage. Our results show that long-term exposure to low-intensity environmental noise can lead to hearing loss via the disruption of ribbon synapses, which is caused by an inflammatory reaction. Additionally, environmental noise can further aggravate the progression of ARHL. This study expounded the pathogenesis of the inner ear damage caused by environmental noise exposure and provides a new direction for the prevention and treatment of hearing loss.

Let the Children Listen: A First Approximation to the Sound Environment Assessment of Children through a Soundwalk Approach

The urban sound environment is one of the layers that characterizes a city, and several methodologies are used for its assessment, including the soundwalk approach. However, this approach has been tested mainly with adults. In the work presented here, the aim is to investigate a soundwalk methodology for children, analyzing the sound environment of five different sites of Gothenburg, Sweden, from children's view-point, giving them the opportunity to take action as an active part of society. Both individual assessment of the sound environment and acoustic data were collected. The findings suggested that among significant results, children tended to rank the sound environment as slightly better when lower levels of background noise were present ( L A 90 ). Moreover, traffic dominance ratings appeared as the best predictor among the studied sound sources: when traffic dominated as a sound source, the children rated the sound environment as less good. Additionally, traffic volume appeared as a plausible predictor for sound environment quality judgments, since the higher the traffic volume, the lower the quality of the sound environment. The incorporation of children into urban sound environment research may be able to generate new results in terms of children's understanding of their sound environment. Moreover, sound environment policies can be developed from and for children.

Environmental Noise Classification Using Convolutional Neural Networks with Input Transform for Hearing Aids

Hearing aids are essential for people with hearing loss, and noise estimation and classification are some of the most important technologies used in devices. This paper presents an environmental noise classification algorithm for hearing aids that uses convolutional neural networks (CNNs) and image signals transformed from sound signals. The algorithm was developed using the data of ten types of noise acquired from living environments where such noises occur. Spectrogram images transformed from sound data are used as the input of the CNNs after processing of the images by a sharpening mask and median filter. The classification results of the proposed algorithm were compared with those of other noise classification methods. A maximum correct classification accuracy of 99.25% was achieved by the proposed algorithm for a spectrogram time length of 1 s, with the correct classification accuracy decreasing with increasing spectrogram time length up to 8 s. For a spectrogram time length of 8 s and using the sharpening mask and median filter, the classification accuracy was 98.73%, which is comparable with the 98.79% achieved by the conventional method for a time length of 1 s. The proposed hearing aid noise classification algorithm thus offers less computational complexity without compromising on performance.

Population variability under stressors is dependent on body mass growth and asymptotic body size

The recruitment and biomass of a fish stock are influenced by their environmental conditions and anthropogenic pressures such as fishing. The variability in the environment often translates into fluctuations in recruitment, which then propagate throughout the stock biomass. In order to manage fish stocks sustainably, it is necessary to understand their dynamics. Here, we systematically explore the dynamics and sensitivity of fish stock recruitment and biomass to environmental noise. Using an age-structured and trait-based model, we explore random noise (white noise) and autocorrelated noise (red noise) in combination with low to high levels of harvesting. We determine the vital rates of stocks covering a wide range of possible body mass (size) growth rates and asymptotic size parameter combinations. Our study indicates that the variability of stock recruitment and biomass are probably correlated with the stock's asymptotic size and growth rate. We find that fast-growing and large-sized fish stocks are likely to be less vulnerable to disturbances than slow-growing and small-sized fish stocks. We show how the natural variability in fish stocks is amplified by fishing, not just for one stock but for a broad range of fish life histories.

Road Traffic Noise Exposure and Depression/Anxiety: An Updated Systematic Review and Meta-Analysis

Unlike other World Health Organization evidence reviews, the systematic review on mental disorders could not provide a quantitative estimate of the effect of environmental noise. With that in mind, we aimed to update it with additional studies published through to 18 August 2019 in order to allow for a formal meta-analysis of the association of residential road traffic noise with anxiety and depression. The quality effects and random effects estimators were used for meta-analysis and the robustness of findings was tested in several sensitivity analyses. Ten studies were included in the qualitative synthesis, from which we extracted 15 estimates for depression (n = 1,201,168) and five for anxiety (n = 372,079). Almost all studies were cross-sectional and the risk of bias in them was generally high. We found 4% (95% CI: -3%, 11%) higher odds of depression and 12% (95% CI: -4%, 30%) of anxiety associated with a 10 dB(A) increase in day-evening-night noise level (Lden). Both models suffered from moderate heterogeneity (55% and 54%), but there was evidence of publication bias only in the depression model. These findings were robust with no evidence of study-level moderators. A sensitivity analysis on an alternative set of categorically-reported estimates supported a linear relationship between Lden and depression. Taking into account an overall quality assessment for the included studies, we conclude that there is evidence of "very low" quality that increasing exposure to road traffic noise may be associated with depression and anxiety.

Workplace noise exposure and audiometric thresholds in dental technicians

Noise is a well-known risk factor in occupational medicine. Several studies have been performed in workplaces with noise sources, especially in the industrial field; on the contrary, only a few studies have been carried to evaluate the noise exposure effects in non-industrial workplaces such as small factories, handicraft laboratories, and dental laboratories. The aims of this study were to evaluate workplace noise exposure and hearing thresholds in dental technicians. Four laboratories and 51 dental technicians were included in the study. Noise exposure levels during a nominal eight-hour working day (LEX, 8 h) were assessed in the included laboratories. Audiometric thresholds with pure tone audiometry were performed in 51 dental technicians, and results were compared with those expected in subjects not exposed to noise. The environmental noise measures showed moderate differences of the LEX, 8 h among the four laboratories (range 71.4 to 76.2); average LEX, 8 h was 73.9 ± 2.2 dB(A). The audiometric results showed a progressive increase of hearing threshold values at the frequencies mostly involved in noise-induced hearing loss (3, 4 and 6 kHz) and a correlation with age and working seniority especially in males (p<0.005). Nevertheless, in the 92.1% of subjects the threshold increases were in line with those expected in subjects of the same age and sex not exposed to noise and in the remaining 7.8% were not statistically significant (p>0.05). In 3.9% of the cases the increases were bilateral, typical of noise-induced hearing loss, and only 1.9% showed involvement of several frequencies with worsening of expected thresholds >25 dB. In conclusion, our study showed that exposure to noise in dental laboratories was not sufficient to represent a hazard to hearing, as demonstrated by the LEX, 8 h, which were below 80 dB(A) and therefore below the European exposure limit values and exposure action values for workers.

Road Traffic Noise Exposure and Birth Outcomes: An Updated Systematic Review and Meta-Analysis

Unlike the other WHO evidence reviews, the systematic review on birth outcomes could not provide a quantitative estimate of the effect of environmental noise. With that in mind, we aimed to update it with additional studies published through to 12 May, 2019 to allow for a formal meta-analysis of the association of residential road traffic noise with birth weight, low birth weight (LBW), small for gestational age (SGA), and preterm birth (PTB). The quality effects and random effects estimators were used for meta-analysis and the robustness of findings was tested in several sensitivity analyses. Nine studies were included in the qualitative synthesis, from which we extracted seven estimates for birth weight (n = 718,136 births) and LBW (n = 620,221), and five for SGA (n = 547,256) and PTB (n = 74,609). We found -8.26 g (95% CI: -20.61 g, 4.10 g) (I2 = 87%) lower birth weight associated with a 10 dB(A) increase in day-evening-night noise level (Lden), and this effect became significant in sensitivity analyses. No evidence of significant effects was found for LBW (OR = 1.06; 95% CI: 0.91, 1.23) (I2 = 49%), SGA (OR = 1.02; 95% CI: 0.86, 1.21) (I2 = 90%), or PTB (OR = 1.00; 95% CI: 0.79, 1.27) (I2 = 69%). The quality of evidence for continuous birth weight was graded as "moderate", while for the other outcomes it was deemed "very low". Finally, we discuss limitations of the risk of bias assessment criteria employed by Nieuwenhuijsen et al.

Burden of Disease Due to Traffic Noise in Germany

Traffic noise is nearly ubiquitous and thus can affect the health of many people. Using the German noise mapping data according to the Directive 2002/49/EC of 2017 and exposure-response functions for ischemic heart disease, noise annoyance and sleep disturbance assessed by the World Health Organization's Environmental Noise Guidelines for the European Region the burden of disease due to traffic noise is quantified. The burden of disease is expressed in disability-adjusted life years (DALYs) and its components. The highest burden was found for road traffic noise, with 75,896 DALYs when only considering moderate evidence. When including all available evidence, 176,888 DALYs can be attributable to road traffic noise. The burden due to aircraft and railway noise is lower because fewer people are exposed. Comparing the burden by health outcomes, the biggest share is due to ischemic heart disease (90%) in regard to aircraft noise, however, the lowest evidence was expressed for the association between traffic noise and ischemic heart disease. Therefore, the results should be interpreted with caution. Using alternative input parameters (e.g., exposure data) can lead to a much higher burden. Nevertheless, environmental noise is an important risk factor which leads to considerable loss of healthy life years.

Exploring the Relationship between Urban Quiet Areas and Perceived Restorative Benefits

To help mitigate the adverse health impacts of environmental noise, European cities are recommended to identify urban quiet areas for preservation. Procedures for identifying urban quiet areas vary across cities and between countries, and little is known of the strength of the salutogenic (health-promoting) benefits they may provide. Taking a multi-site approach, this study examines the potential of three sites as urban quiet areas and their associated health benefits, particularly in relation to perceived restorative benefits. Across three cities in the United Kingdom, an urban garden, urban park, and an urban square had sound pressure levels measured. Responses from 151 visitors to these sites evaluated the place as quiet, calm, and tranquil, and assessed their experience of the place in terms of perceived sounds, its benefits, how it made them feel, and perceived restoration. Depending on the criteria used, the sites varied in their suitability as urban quiet areas, although all provided perceived health benefits. Relationships between sound levels (subjective and objective) and perceived restoration were not linear, with the type of sounds heard and other aspects of the place experience believed to affect the relationship. Building on this work, a future experimental approach based on the study sites is planned to manipulate the multiple variables involved. This will provide a clearer understanding of the relationship between urban quiet areas and perceived restorative benefits.

Vibrational mating disruption of Empoasca vitis by natural or artificial disturbance noises

BACKGROUND

The green leafhopper, Empoasca vitis, is a polyphagous pest of grapevine and tea plants. To date population density is controlled primarily by insecticides and there is a demand for more sustainable controls. To develop a vibrational mating disruption method, the natural occurrence of a 'disruptive signal' was investigated. Further, the efficacy of natural and artificial 'disruptive signals' was determined.

RESULTS

With behavioral trials we described male rivalry and recorded a species-specific disruptive signal (DP). The DP, a single pulse overlapping the competitor male call, interfered with the rival's ability to locate the female. Laboratory playback disruption trials revealed that the pair formation process was prevented by artificial disturbance noises that included the following features: E. vitis DP, Scaphoideus titanus disturbance noise, and a pure tone (250 Hz). Among these, the pure tone was most efficient at preventing mating.

CONCLUSION

Results support development of a vibrational mating disruption method as a control strategy for E. vitis. To simultaneously disrupt the mating of E. vitis and S. titanus, the possibility of applying the S. titanus disturbance noise combined with the pure tone is discussed. © 2018 Society of Chemical Industry.

Trait-based predictions and responses from laboratory mite populations to harvesting in stochastic environments

Predictions on population responses to perturbations are often derived from trait-based approaches like integral projection models (IPMs), but are rarely tested. IPMs are constructed from functions that describe survival, growth and reproduction in relation to the traits of individuals and their environment. Although these functions comprise biologically non-informative statistical coefficients within standard IPMs, model parameters of the recently developed dynamic energy budget IPM (DEB-IPM) are life-history traits like "length at maturation" and "maximum reproduction rate". Testing predictions from mechanistic IPMs against empirical observations can therefore provide functional insights into the links between individual life history, the environment and population dynamics. Here, we compared the population dynamics of the bulb mite (Rhizoglyphus robini) predicted by a DEB-IPM with those observed in an experiment where populations experienced daily food rations that were either positively correlated over time (red noise), negatively (blue noise) or uncorrelated (white noise). We also selectively harvested large adults in half of these populations. The model failed to generate detailed predictions of population structure as juvenile numbers were overestimated; likely because juvenile-adult interference competition was underestimated. The model performed well at the population level as, for both harvested and unharvested populations, simulations matched the observed, long-term stochastic growth rate λ_s . We next generalised the model to investigate how stochastic change affects mite λ_s , which correlated well with the frequency f of experiencing periods of good environment, but, due to the relationship between f and noise colour ρ, did not correlate well with shifts in ρ. The sensitivity of λ_s to perturbations in life-history parameters depended on the type of stochastic change, as well as population growth. Our findings show that responses to differential mortality depend on individual life-history traits, environmental characteristics and population growth. As long-term climate change causes ever greater environmental fluctuations, trait-based approaches will be increasingly important in predicting population responses to change. We therefore conclude by illustrating what questions can be examined with mechanistic trait-based models like the DEB-IPM, the answers to which will advance our knowledge of the functional links between individual traits, the environment and population dynamics.

Sleep quality and noise: comparisons between hospital and home settings

BACKGROUND

Children and their parents report poor sleep in hospital and complain about noise.

OBJECTIVE

To measure sleep quality and noise levels in hospital and compare these with the home environment.

DESIGN

Observational within case-controlled study.

SETTING

Paediatric medical wards at Southampton Children's Hospital and bedrooms at home.

PARTICIPANTS AND METHODS

Participants were children aged 3-16 years and their co-sleeping parents. Sleep quality was measured using actigraphy for a maximum of 5 nights in each setting. Median sound levels at the bedside were monitored overnight in a subgroup in both settings.

MAIN OUTCOME MEASURES

Total sleep time, sleep efficiency, median sound levels overnight.

RESULTS

40 children and 16 mothers completed actigraphy in both settings. Children had on average 62.9 min, and parents 72.8 min, per night less sleep in hospital than at home. Both children and parents had poorer sleep quality in hospital than at home: mean sleep efficiency 77.0% vs 83.2% for children and 77.1% vs 88.9% for parents, respectively. Median sound levels in hospital measured in 8 children averaged 48.6 dBA compared with 34.7 dBA at home and exceeded World Health Organization recommendations of 30 dB.

CONCLUSIONS

Children and their mothers have poor quality sleep in paediatric wards. This may affect the child's behaviour, recovery and pain tolerance. Sleep deprivation adds to parental burden and stress. Sound levels are significantly raised in hospital and may contribute to poor sleep. Reduction in the level of noise might lead to an improvement in sleep, affecting the quality of stay of both parent and child.