A meta-analysis of 14 studies (17 individual effect estimates) on the association between road traffic noise and coronary heart diseases was carried out. A significant pooled estimate of the relative risk of 1.08 (95% confidence interval: 1.04, 1.13) per increase of the weighted day-night noise level L _DN of 10 dB (A) was found within the range of approximately 52-77 dB (A) (5 dB-category midpoints). The results gave no statistically significant indication of heterogeneity between the results of individual studies. However, stratified analyses showed that the treatment of gender in the studies, the lowest age of study subjects and the lowest cut-off of noise levels had an impact on the effect estimates of different studies. The result of the meta-analysis complies quantitatively with the result of a recent meta-analysis on the association between road traffic noise and hypertension. Road traffic noise is a significant risk factor for cardiovascular diseases.

The main aim of this paper is to present recent knowledge about the assessment and evaluation of low-frequency sounds (noise) and infrasound, close to the threshold of hearing, and identify their potential effect on human health and annoyance. Low-frequency noise generated by air flowing over a moving car with an open window was chosen as a typical scenario which can be subjectively assessed by people traveling by automobile. The principle of noise generated within the interior of the car and its effects on the comfort of the driver and passengers are analyzed at different velocities. An open window of a car at high velocity behaves as a source of specifically strong tonal low-frequency noise which is generally perceived as annoying. The interior noise generated by an open window of a passenger car was measured under different conditions: Driving on a highway and driving on a typical roadway. First, an octave-band analysis was used to assess the noise level and its impact on the driver's comfort. Second, a fast Fourier transform (FFT) analysis and one-third octave-band analysis were used for the detection of tonal low-frequency noise. Comparison between two different car makers was also done. Finally, the paper suggests some possibilities for scientifically assessing and evaluating low-frequency sounds in general, and some recommendations are introduced for scientific discussion, since sounds with strong low-frequency content (but not only strong) engender greater annoyance than is predicted by an A-weighted sound pressure level.

The problem of noise has recently gained more attention as it has become an integral part of our daily lives. However, its influence has yet to be fully elucidated. Other than being an unpleasant stimulus, noise may cause health disorders through annoyance and stress, including oxidative stress. Rosuvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, may possess antioxidant properties. Based on rat models, our project investigates the effect of rosuvastatin on noise-induced oxidative stress in the brain tissue. Thirty-two male Wistar albino rats were used. The rats were divided into four groups: Noise exposure plus rosuvastatin usage, only noise exposure, only rosuvastatin usage, and control. After the data had been collected, oxidant and antioxidant parameters were analyzed in the cerebral cortex, brain stem, and cerebellum. Results indicated that superoxide dismutase values were significantly decreased in the cerebral cortex, while malondialdehyde values in the brainstem and cerebellum were significantly increased in the group with only noise exposure. Superoxide dismutase values in the brainstem were significantly increased, but nitric oxide values in the cerebellum and brainstem and malondialdehyde values in the cerebellum and cerebral cortex were significantly decreased in the group where only rosuvastatin was used. During noise exposure, the use of rosuvastatin caused significantly increased superoxide dismutase values in the cerebral cortex and brainstem, but significantly reduced malondialdehyde values in the brain stem. Consequently, our data show that brain tissue was affected by oxidative stress due to continued exposure to noise. This noise-induced stress decreases with rosuvastatin therapy.

The main goal of this study was to assess the prevalence and characteristics of tinnitus among students after exposure to leisure noise. In addition, the effects of tinnitus on otoacoustic emissions (OAEs) in participants suffering from chronic tinnitus were evaluated. The study consisted of two parts. First, a questionnaire regarding leisure noise exposure and tinnitus was completed. Second, the hearing status of the subjects suffering from chronic tinnitus was evaluated and compared with a matched control group (CG). Furthermore, the psychoacoustical characteristics of their tinnitus in the chronic tinnitus group (TG) were established. The questionnaire was answered by 151 respondents. Seven persons suffering from chronic tinnitus were examined further in the second part of the study. Transient tinnitus was observed in 73.5% of the respondents after leisure noise exposure and 6.6% experienced chronic tinnitus. Transient and chronic tinnitus had similar characteristics, as established by the questionnaire. The amplitude of transient evoked otoacoustic emissions and distortion product otoacoustic emissions was reduced and the amount of efferent suppression was smaller in the TG as compared with the CG. Tinnitus induced by leisure noise is observed frequently in young adults. The characteristics of tinnitus cannot predict whether it will have a transient or rather a chronic nature. In subjects suffering from tinnitus, subclinical damage that cannot be detected by audiometry can be demonstrated by measuring OAEs. These findings underpin the importance of educating youth about the risks of noise exposure during leisure activities.

Ringtones are designed to draw attention away from on-going activities. In the present study, it was investigated whether the disruptive effects of a ringing cell phone on short-term memory are inevitable or become smaller as a function of exposure and whether (self-) relevance plays a role. Participants performed a serial recall task either in silence or while task-irrelevant ringtones were presented. Performance was worse when a ringing phone had to be ignored, but gradually recovered compared with the quiet control condition with repeated presentation of the distractor sound. Whether the participant's own ringtone was played or that of a yoked-control partner did not affect performance and habituation rate. The results offer insight into auditory distraction by highly attention-demanding distractors and recovery therefrom. Implications for work environments and other applied settings are discussed.

For musicians, the impact of noise exposure is not yet fully characterized. Some inconsistencies can be found in the methodology used to evaluate noise exposure. This study aims to analyze the noise exposure of musicians in a symphonic orchestra to understand their risk for hearing loss, applying the methodology proposed by ISO 9612:2009. Noise levels were monitored among musicians during the rehearsal of eight different repertoires. Test subjects were selected according to their instrument and position in the orchestra. Participants wore noise dosimeters throughout the rehearsals. A sound meter was used to analyze the exposure of the conductor. The results showed that musicians are exposed to high noise levels that can damage hearing. Brass, woodwind and percussion and timpani musicians were exposed to noise levels in excess of the upper exposure action level of 85 dB (A), while the other instrumental groups had a lower exposure action level of 80 dB (A). Percussion musicians were exposed to high peak noise levels of 135 dB (C). Sound levels varied by instrument, repertoire and position. Octave frequency analyses showed differences among musicians. This study suggests that musicians are at risk for hearing loss. There is a need for more effective guidelines applicable to all countries, which should define standardized procedures for determining musician noise exposure and should allow exposure level normalization to the year, including different repertoires.

The concept of noise sensitivity emerged in public health and psychoacoustic research to help explain individual differences in reactions to noise. Noise sensitivity has been associated with health problems, but the mechanisms underlying this relationship have yet to be fully examined. Participants (n = 1102) were residents of Auckland, New Zealand, who completed questionnaires and returned them through the post. Models of noise sensitivity and health were tested in the analyses using bootstrapping methods to examine indirect effects. Results indicated that gender and noise exposure were not significant moderators in the model. Perceived stress and sleep problems were significant mediators of the relationship between noise sensitivity and subjective health complaints, even after controlling for the influence of neuroticism. However, the relationship between noise sensitivity and mental health complaints (anxiety and depression) was accounted for by the variance explained by neuroticism. Overall, this study provides considerable understanding of the relationship between noise sensitivity and health problems and identifies areas for further research in the field.

It is poor in the literature the behavior of the geometric indices of heart rate variability (HRV) during the musical auditory stimulation. The objective is to investigate the acute effects of classic musical auditory stimulation on the geometric indexes of HRV in women in response to the postural change maneuver (PCM). We evaluated 11 healthy women between 18 and 25 years old. We analyzed the following indices: Triangular index, Triangular interpolation of RR intervals and Poincarι plot (standard deviation of the instantaneous variability of the beat-to beat heart rate [SD1], standard deviation of long-term continuous RR interval variability and Ratio between the short - and long-term variations of RR intervals [SD1/SD2] ratio). HRV was recorded at seated rest for 10 min. The women quickly stood up from a seated position in up to 3 s and remained standing still for 15 min. HRV was recorded at the following periods: Rest, 0-5 min, 5-10 min and 10-15 min during standing. In the second protocol, the subject was exposed to auditory musical stimulation (Pachelbel-Canon in D) for 10 min at seated position before standing position. Shapiro-Wilk to verify normality of data and ANOVA for repeated measures followed by the Bonferroni test for parametric variables and Friedman's followed by the Dunn's posttest for non-parametric distributions. In the first protocol, all indices were reduced at 10-15 min after the volunteers stood up. In the protocol musical auditory stimulation, the SD1 index was reduced at 5-10 min after the volunteers stood up compared with the music period. The SD1/SD2 ratio was decreased at control and music period compared with 5-10 min after the volunteers stood up. Musical auditory stimulation attenuates the cardiac autonomic responses to the PCM.

The objective of this study is to develop a traffic noise model under diverse traffic conditions in metropolitan cities. The model has been developed to calculate equivalent traffic noise based on four input variables i.e. equivalent traffic flow (Q _e ), equivalent vehicle speed (S _e ) and distance (d) and honking (h). The traffic data is collected and statistically analyzed in three different cases for 15-min during morning and evening rush hours. Case I represents congested traffic where equivalent vehicle speed is <30 km/h while case II represents free-flowing traffic where equivalent vehicle speed is >30 km/h and case III represents calm traffic where no honking is recorded. The noise model showed better results than earlier developed noise model for Indian traffic conditions. A comparative assessment between present and earlier developed noise model has also been presented in the study. The model is validated with measured noise levels and the correlation coefficients between measured and predicted noise levels were found to be 0.75, 0.83 and 0.86 for case I, II and III respectively. The noise model performs reasonably well under different traffic conditions and could be implemented for traffic noise prediction at other region as well.