Showing papers in "Noise & Health in 2018"

Noise in the neonatal intensive care unit: a new approach to examining acoustic events

Abstract: Introduction: Environmental noise is associated with negative developmental outcomes for infants treated in the neonatal intensive care unit (NICU). The existing noise level recommendations are outdated, with current studies showing that these standards are universally unattainable in the modern NICU environment. Study Aim: This study sought to identify the types, rate, and levels of acoustic events that occur in the NICU and their potential effects on infant physiologic state. Materials and Methods: Dosimeters were used to record the acoustic environment in open and private room settings of a large hospital NICU. Heart and respiratory rate data of three infants located near the dosimeters were obtained. Infant physiologic data measured at time points when there was a marked increase in sound levels were compared to data measured at time points when the acoustic levels were steady. Results: All recorded sound levels exceeded the recommended noise level of 45 decibels, A-weighted (dBA). The 4-h Leq of the open-pod environment was 58.1 dBA, while the private room was 54.7 dBA. The average level of acoustic events was 11–14 dB higher than the background noise. The occurrence of transient events was 600% greater in the open room when compared to the private room. While correlations between acoustic events and infant physiologic state could not be established due to the extreme variability of infant state, a few trends were visible. Increasing the number of data points to overcome the extreme physiologic variability of medically fragile neonates would not be feasible or cost-effective in this environment. Conclusion: NICU noise level recommendations need to be modified with an emphasis placed on reducing acoustic events that disrupt infant state. The goal of all future standards should be to optimize infant neurodevelopmental outcomes.

Negative impact of noise and noise sensitivity on mental health in childhood

Abstract: Introduction: Noise and noise sensitivity have negative effects on mental health and are not well-studied in children and adolescents. In this study, we investigated these effects in the aforementioned population with respect to sociodemographic variables and environmental factors. Materials and Methods: In this population-based study conducted in two large cities in South Korea, 918 elementary and middle-school students were included. After direct measurements at the selected sites, a noise map was created using an interpolation method. The road traffic noise of the participants’ residential areas was calculated based on this noise map. Noise sensitivity was assessed on an 11-point Likert scale. Using multivariate logistic regression, we investigated the relationship among noise, noise sensitivity, and the Child Behavior Checklist. Further analyses were performed subdividing the data according to household income levels. Results: Noise sensitivity was significantly associated with internalizing, externalizing, and total behavioral problems. Noise was positively associated with total behavioral problems. In the low-income group, the degree of association with problem behaviors was higher, whereas the relationship between noise sensitivity and externalization problems disappeared in the high-income group. Conclusion: Noise and noise sensitivity are negatively associated with the mental health of children and adolescents, particularly in low-income groups. The findings of this study suggest that noise sensitivity and socioeconomic status should be considered in coping with negative effects of noise in children and adolescents.

The effect of aircraft, road, and railway traffic noise on stroke - results of a case-control study based on secondary data.

Abstract: Aim: To examine the stroke risks associated with aircraft, road traffic, and railway noise exposure in a large case–control study. Materials and Methods: All people aged ≥40 years living around the Frankfurt airport that were insured by one of three large statutory health insurance funds between 2005 and 2010 were included in the study (n = 1,026,670). Address-specific exposure to aircraft, road, and railway traffic noise was estimated for 2005. We used insurance claim data to identify 25,495 newly diagnosed cases of stroke between 2006 and 2010 and compared them with 827,601 control participants. Logistic regression analysis was used to calculate the odds ratios adjusted for age, sex, local proportion of people receiving unemployment benefits, and if available individual indicators of socioeconomic status (education, occupation). Results: For 24-h continuous aircraft noise exposure, neither increased risk estimates nor a positive linear exposure–risk relation was found. However, stroke risk was statistically significantly increased by 7% [95% confidence intervals (95%CI): 2–13%] for people who were exposed to

The interactive effect of occupational noise on attention and short-term memory: A pilot study.

Abstract: Introduction: Human performance is influenced by several job-related factors and workplace conditions, including occupational noise. This influence can occur at sound pressure levels lower than the ones that cause physiological damage, such as hearing loss, being mediated by the noise characteristics. However, studies concerning this issue are still scarce. Study. Aim: The aim of this study was to investigate the effects of three noise conditions on attention and short-term memory: standard condition (C1), environmental noise without alarm sounds (C2), and environmental noise with alarm sounds (C3). Materials and Methods: First, noise levels were measured during a normal workweek in a fast food establishment. Second, an experiment was designed to simulate the noise normally prevailing in the workplace. The noise levels were fixed at 45 ± 0.3 dB(A) (C1), 60 ± 0.4 dB(A) (C2), and 68 ± 0.4 dB(A) (C3). The influence of noise on participants’ attention and short-term memory was assessed with the following test battery: serial recall, response inhibition, and Stroop interference. Because annoyance, stress, and discomfort perceptions during the tests can influence results, visual analog scales to assess these variables were applied in the end of each trial. Fifteen undergraduate students were included in this pilot study (20–23 years; M = 21.6; SD = 0.8; all female). Results: The results demonstrated that participants’ performance during the tests was lower in C3, that is, the number of errors was higher and the reaction time longer. Participants also experienced higher levels of discomfort, stress, and annoyance perceptions in this condition. However, task performance was not found to be influenced by these perceptions. Conclusion: This study provided important insights about the different noise conditions that workers are exposed in a fast food restaurant, and how they influence participants’ performance. Further research should involve workers, exploring how these conditions are implicated in their performance in the field.

Public online information about tinnitus: A cross-sectional study of YouTube videos

Abstract: Purpose: To examine the information about tinnitus contained in different video sources on YouTube. Materials and Methods: The 100 most widely viewed tinnitus videos were manually coded. Firstly, we identified the sources of upload: consumer, professional, television-based clip, and internet-based clip. Secondly, the videos were analyzed to ascertain what pertinent information they contained from a current National Institute on Deafness and Other Communication Disorders fact sheet. Results: Of the videos, 42 were consumer-generated, 33 from media, and 25 from professionals. Collectively, the 100 videos were viewed almost 9 million times. The odds of mentioning “objective tinnitus” in professional videos were 9.58 times those from media sources [odds ratio (OR) = 9.58; 95% confidence interval (CI): 1.94, 47.42; P = 0.01], whereas these odds in consumer videos were 51% of media-generated videos (OR = 0.51; 95% CI: 0.20, 1.29; P = 0.16). The odds that the purpose of a video was to sell a product or service were nearly the same for both consumer and professional videos. Consumer videos were found to be 4.33 times as likely to carry a theme about an individual’s own experience with tinnitus (OR = 4.33; 95% CI: 1.62, 11.63; P = 0.004) as media videos. Conclusions: Of the top 100 viewed videos on tinnitus, most were uploaded by consumers, sharing individuals’ experiences. Actions are needed to make scientific medical information more prominently available and accessible on YouTube and other social media.

The study of attenuation levels and the comfort of earplugs

Abstract: Introduction: This study aimed to analyze and compare four different types of earplugs, divided into premolded plugs and foam plug models, in relation to the level of attenuation, comfort, and the size of the external acoustic meatus (EAM) in an attempt to identify how these variables influence the choice of specific hearing protection devices (HPDs). Materials and Methods: A cross-sectional observational study was performed in a sample of 49 participants, oriented toward the ideal placement of four HPDs, two premolded and two foam plugs (3M™). The procedures included otoscopy, EAM diameter measurement using an otometer, EAM volume measurement via an acoustic impedance test, and the obtainment of the bilateral personal attenuation rating (PAR) for each HPD using the E-A-Rfit™ Validation System (3M™). The Bipolar Comfort Rating Scale (BCRS) instrument was applied twice for each individual: once after the evaluations with the premolded HPDs and again after the evaluations with the foam plug HPDs. Then, each participant was asked which was his/her favorite protector. Results: The volume of the EAM was not directly related to the diameter of the EAM. The attenuation did not interfere with the HPD preference, and the PAR of the foam plug was significantly higher regardless of the preferred HPD. Regarding the BCRS, the variables “Placement,” “Complexity,” and “Occlusion Effect” had higher scores for premolded HPDs and had a direct relationship with the type of preferred HPD. Conclusion: Attention to the use of HPDs should be personalized, taking into account the needs of each individual, considering not only the attenuation, but also the user’s reported well-being.

Influences of combined traffic noise on the ability of learning and memory in mice

Abstract: Objective: The present study aimed to evaluate the influences of combined traffic noise (CTN) on the ability of learning and memory in mice. Materials and Methods: The Institute of Cancer Research (ICR) mice were exposed to CTN from highways and high-speed railways for 42 days, whose day–night equivalent continuous A-weighted sound pressure level (Ldn) was 70 dB(A). On the basis of behavioral reactions in Morris water maze (MWM) and the concentrations of amino acid neurotransmitters in the hippocampus, the impacts of CTN on learning and memory in mice were examined. Results: The MWM test showed that the ability of learning and memory in mice was improved after short-term exposure (6–10 days, the first batch) to 70 dB(A) CTN, which showed the excitatory effect of stimuli. Long-term exposure (26–30 days, the third batch; 36–40 days, the fourth batch) led to the decline of learning and memory ability, which indicated the inhibitory effect of stimuli. Assays testing amino acid neurotransmitters showed that the glutamate level of the experimental group was higher than that of the control group in the first batch. However, the former was lower than the latter in the third and fourth batches. Both, behavioral reactions and the concentrations of amino acid neurotransmitters, testified that short-term exposure and long-term exposure resulted in excitatory effect and inhibitory effect on the ability of learning and memory, respectively. Conclusion: The effects of 70 dB(A) CTN on the ability of learning and memory were closely related to the exposure duration. Furthermore, those effects were regulated and controlled by the level of glutamate in the hippocampus.

Health-related quality of life is impacted by proximity to an airport in noise-sensitive people.

Abstract: Introduction: The aim of the study was to determine whether those who are noise sensitive are more adversely affected by airport noise than those who are not noise sensitive. Participants and Methods: One area was very close to Wellington International Airport and the other was distant from the airport and any other major sources of noise such as motorways and railways. Noise sensitivity was self-rated on a three-point scale as follows: non-noise sensitive, moderately noise sensitive, or highly noise sensitive. Statistical analysis consisted of analyses of variance using the domains of the WHOQOL score with the year, area (airport or the control), and noise sensitivity as covariates. Results: Noise-sensitive people were found to have a significantly poorer HRQOL than others when they lived near an airport, but not when they lived in the control area. The same effect was present at both of the time points investigated, suggesting that it is a general finding. Discussion: This finding is consistent with similar studies using the WHOQOL-BREF for investigating noise from road traffic, suggesting consistency in effect across transport noise sources.

Association between polymorphism of tumor necrosis factor alpha (tnfα) in the region -308 g/a with tinnitus in the elderly with a history of occupational noise exposure.

Abstract: Context: Tinnitus is a common disorder that occurs frequently across all strata of population and has an important health concern and is often associated with different forms of the hearing loss of varying severity. Aims: To investigate the association between the polymorphism of tumor necrosis factor alpha (TNFα) in the region −308 G/A with the susceptibility to tinnitus in individuals with the history of exposure to occupational noise. Settings and Design: This was a cross-sectional study with a sample of 179 independent elderly people above 60 years of age. Materials and Methods: Information on exposure to occupational noise was obtained by interviews. Audiological evaluation was performed using pure tone audiometry and genotyped through polymerase chain reaction by restriction fragment length polymorphism. Statistical Analysis Used: Data were analyzed using the chi-square test and the odds ratio (OR), with the significance level set at 5%. Results: Among elderly with tinnitus (43.01%), 33.76% had a history of exposure to occupational noise. A statistically significant association was found between genotype frequencies of the TNFα gene in the −308 G/A region and the complaint of tinnitus (P = 0.04 and χ2 = 4.19). The elderly with the G allele were less likely to have tinnitus due to occupational noise exposure when compared to those carrying the A allele (OR = 2.74; 95% CI: 1.56–4.81; P

Community noise exposure and annoyance, activity interference, and academic achievement among university students.

Abstract: Background: Noise annoyance and effects on academic performance have been investigated for primary and secondary school students but comparatively little work has been conducted with university students who generally spend more time in dormitories or accommodation for their self-study. Objective: To determine, using a socio-acoustic approach involving face-to-face interviews and actual noise measurements, the effect of various community noise sources on student activities in accommodation both inside and outside a university precinct and also relationships with cumulative grade point average (GPA). Materials and Methods: The study sample comprised a student group resident off-campus (n = 450) and a control group resident in dormitories on-campus (n = 336). Noise levels [LA (dB)] were measured at both locations according to International Organization for Standardization standards. The extent of community noise interference with the student activities was examined with bivariate and stratified analyses and results presented as Mantel–Haenszel weighted odds ratios (ORMH) with 95% confidence intervals. Binary logistic regression was employed to assess the association between noise-disturbed student activities and dichotomized GPA values and derive odds ratios (ORs) for these associations. Results: Measured noise levels were all significantly (P < 0.05) higher for off-campus students. This was not reflected in the interviewed students’ subjective perceptions of how “noisy” their respective environments were. The off-campus student cohort was, however, more annoyed by all community noise categories (P < 0.001) except road traffic noise. For impact on specific student activities, the largest differences between on- and off-campus students were found for telephone and personal communication regardless of the type of community noise. There was no significant difference in the relationships between perceived annoyance due to community noise categories and cumulative GPA in the off-campus group compared to those for on-campus residents with ORMH values ranging from 1.049 to 1.164. The most important noise-impacted factors affecting off-campus students’ cumulative GPA were reading and mental tasks (OR = 2.801). Rest disturbance had a positive influence on cumulative GPA for on-campus students. Conclusion: These results provide support that various contemporary community noise sources affect university students’ activities and possibly influence their educational achievement as well.

Impacts of low frequency noise exposure on well-being: a case-study from portugal.

Abstract: The authors would like to acknowledge CAPES/Brazil (Process: BEX1684-13/2) for the financial support given to Dr. Pedro Arezes (Ergonomics Laboratory/University of Minho) for the dedicated orientation and technical support intheadaptedaudiometrictests,toFilipaManuelaNetoPaiva (Student at the Faculty of Engineering/University of Minho) for the technical support in audiometric tests, as well as the Serzedelo Village Council and Abacao and Gemeos Village Council for helping us to recruit volunteers.

The hearing of rural workers exposed to noise and pesticides.

Abstract: n work environments, different physical and chemical agents that may pose a risk to workers' hearing health coexist. In this context, occupational hearing loss stands out. It has mostly been attributed to only noise exposure, although there are other agents, that is, pesticides that might contribute to occupational hearing loss. In this report, two cases will be presented that consider rural workers exposed to pesticides and intense noise generated by an adapted rudimentary vehicle. The noise measured in this vehicle was 88.3 dBA up to 93.4 dBA. Pure-tone audiometry, distortion product otoacoustic emissions, and high-frequency audiometry tests were performed. This report is unusual because of the short time of exposure to noise and pesticides and the hearing loss found, indicating a synergy between those agents.

A profile of noise sensitivity on the health-related quality of life among young motorcyclists

Abstract: Introduction: Motorcycle riders with noise sensitivity (NS) may suffer from degraded health-related quality of life (HRQOL) because they are exposed to acute noise levels on a daily basis. Materials and Methods: This study was aimed to identify the relationship between NS and HRQOL among young motorcycle riders (undergraduate university students) aged between 19 and 25 years (n = 301) through a cross-sectional questionnaire-based study, that is, Weinstein noise sensitivity scale and the World Health Organization Quality of Life. The effects of NS on HRQOL were assessed based on gender, the years of motorcycle driving experience, and noise sensitive among groups using one-way analysis of variances with an alpha value of 0.05. Results: The results showed no significant difference in NS between males and females. On the other hand, motorcycle driving experience for

Noise exposure and hearing loss in classical orchestra musicians: A five-year follow-up.

Abstract: Introduction: This study is a follow-up to prior research from our group that attempts to relate noise exposure and hearing thresholds in active performing musicians of the National Ballet of Canada Orchestra. Materials and Methods: Exposures obtained in early 2010 were compared to exposures obtained in early 2017 (the present study). In addition, audiometric thresholds obtained in early 2012 were compared to thresholds obtained in early 2017 (the present study). This collection of measurements presents an opportunity to observe the regularities in the patterns of exposure as well as threshold changes that may be expected in active orchestra musicians over a 5-year span. Results: The pattern of noise exposure across instrument groups, which was consistent over the two time points, reveals highest exposures among brass, percussion/basses, and woodwinds. However, the average noise exposure across groups and time was consistently below 85 dBA, which suggests no occupational hazard. These observations were corroborated by audiometric thresholds, which were generally (a) in the normal range and (b) unchanged in the 5-year period between measurements. Conclusion: Because exposure levels were consistently below 85 dBA and changes in audiometric thresholds were minimal, we conclude that musicians experienced little-to-no risk of noise-induced hearing loss.

The test–retest reliability of questionnaires regarding attitudes and beliefs toward noise, hearing loss, and hearing protector devices in young adults

Abstract: Context: Young people expose themselves to high noise levels during leisure activities, and might thus be at risk of acquiring hearing-related problems Therefore, information regarding risk-taking behavior is necessary to prevent future hearing problems and to optimize future preventive campaigns Aim: This study evaluated the test–retest reliability of the Youth Attitude to Noise Scale (YANS) and beliefs about hearing protection and hearing loss (BAHPHL) instrument Settings and Design: Forty-three young adults between 18 and 29 years filled in a questionnaire at two test moments Materials and Methods: The YANS and BAHPHL instrument were used to evaluate the attitudes toward noise, hearing loss, and hearing protection Each participant completed the retest within 21–55 days after the first administration of the questionnaire Results: Paired Student’s t-tests showed no significant differences in mean scores between test and retest for both the entire YANS and BAHPHL instrument as well as their factors Furthermore, a good agreement between test and retest scores was seen by Bland–Altman analyses Intraclass correlation coefficients were above 070 for the entire YANS and the factor related to youth culture as well as for the entire BAHPHL and all the factors of the BAHPHL instrument, except for the factor related to the severity of the consequences of hearing loss Conclusion: Reliable test–retest measurements of the YANS and BAHPHL instrument can be performed Hence, these questionnaires can be used in longitudinal studies to explore young adults’ changes in attitudes toward noise, hearing loss, and hearing protection, with or without an educational intervention

Noise exposure and hearing status among call center operators

Abstract: Introduction: The overall objective of the study was to assess noise exposure and audiometric hearing threshold levels (HTLs) in call center operators. Materials and Methods: Standard pure-tone audiometry and extended high-frequency audiometry were performed in 78 participants, aged 19 to 44 years (mean ± standard deviation: 28.1 ± 6.3 years), employed up to 12 years (2.7 ± 2.9 years) at one call center. All participants were also inquired about their communication headset usage habits, hearing-related symptoms, and risk factors for noise-induced hearing loss (NIHL). Noise exposure under headsets was evaluated using the microphone in a real ear technique as specified by ISO 11904-1:2002. The background noise prevailing in offices was also measured according to ISO 9612:2009. Results and Discussion: A personal daily noise exposure level calculated by combining headset and nonheadset work activities ranged from 68 to 79 dBA (74.7 ± 2.5 dBA). Majority (92.3%) of study participants had normal hearing in both ears (mean HTL in the frequency range of 0.25–8 kHz ≤20 dB HL). However, their HTLs in the frequency range of 0.25 to 8 kHz were worse than the expected median values for equivalent highly screened otologically normal population, whereas above 8 kHz were comparable (9–11.2 kHz) or better (12.5 kHz). High-frequency hearing loss (mean HTLs at 3, 4, and 6 kHz >20 dB HL) and speech-frequency hearing loss (mean HTLs at 0.5, 1, 2, and 4 kHz >20 dB HL) were noted in 8.3% and 6.4% of ears, respectively. High-frequency notches were found in 15.4% of analyzed audiograms. Moreover, some of call center operators reported hearing-related symptoms. Conclusions: Further studies are needed before firm conclusions concerning the risk of NIHL in this professional group can be drawn.

Effects of parenteral papaverine and piracetam administration on cochlea following acoustic trauma

Abstract: Introduction: Noise exposure, the main cause of hearing loss in countries with lot of industries, may result both in temporary or permanent hearing loss. The goal of this study was to investigate the effects of parenteral papaverine and piracetam administration following an acoustic trauma on hearing function with histopathologic correlation. Materials and Methods: Eighteen Wistar albino rats exposed to noise for 8 h in a free environment were included. We divided the study population into three groups, and performed daily intraperitoneal injections of papaverine, piracetam, and saline, respectively, throughout the study. We investigated the histopathologic effects of cellular apoptosis on inner hair cells (IHCs) and outer hair cells (OHCs) and compared the distortion product otoacoustic emissions (DPOAEs) thresholds among the groups. Results and Discussion: On the 3rd and 7th days, DPOAE thresholds at 8 kHz were significantly higher both in papaverine and piracetam groups compared with the control group (P = 0.004 for 3rd day, P = 0.016 and P = 0.028 for 7th day, respectively). On the 14th day, piracetam group had significantly higher mean thresholds at 8 kHz (P = 0.029); however, papaverine group had similar mean thresholds compared to the control group (P = 0.200). On the 3rd and 7th days following acoustic trauma, both IHC and OHC loss were significantly lower in both papaverine and piracetam groups. On the 7th day, the mean amount of apoptotic IHCs and OHCs identified using Caspase-3 method were significantly lower in both groups, but the mean amount identified using terminal deoxynucleotidyl transferase dUTP nick end labeling method were similar in both groups compared to the control group. Conclusion: We demonstrated the effects of papaverine and piracetam on the recovery of cochlear damage due to acoustic trauma on experimental animals using histopathologic and electrophysiologic examinations.

The assessment of exposure to occupational noise and hearing loss for stoneworkers in taiwan

Abstract: Introduction: Stoneworkers in Taiwan are exposed to occupational noise and suffer hearing impairment. A complete assessment of exposure and health effects is needed for a better understanding. Materials and Methods: We accessed nine stone factories, monitored the environmental and personal doses of noise, analyzed the frequency spectra of noise from various machines, and recruited 55 stoneworkers and 25 administrative staff as controls for pure tone audiometry testing. Results: The means (standard deviations) of 8-h time-weighted averages for environmental and personal monitoring were 85.0 (6.2) and 87.0 (5.5) dB(A), respectively, with seven of nine personal measurements being higher than the respective environmental results. The monitoring data suggest that occupational noise in the stonework environments should be a matter of great concern. Nearly all frequency spectra indicated peak values occurring between 2 and 4 kHz, which were within the bands for early noise-induced hearing loss (NIHL). The mean hearing threshold levels of the study participants were elevated in low and high frequencies (29.2 and 41.2 dB) compared to that of controls (∼25 dB for both bands). Linear regression analysis indicated no significance in the low frequencies (P = 0.207) but statistical significance in the high frequencies (P = 0.002) after adjustment for covariates, suggesting NIHL among the stoneworkers. Conclusion: Stoneworkers apparently display early signs of NIHL. Noises in the stonework factories with peaks in the high frequencies are harmful to hearing ability. Employers and workers have to comply with the regulation strictly to prevent further hearing damage.

Utility of otoacoustic emissions and olivocochlear reflex in predicting vulnerability to noise-induced inner ear damage.

Abstract: Aim: The aim of the present study was to explore the possible utility of otoacoustic emissions (OAEs) and efferent system strength to determine vulnerability to noise exposure in a clinical setting. Materials and Methods: The study group comprised 344 volunteers who had just begun mandatory basic training as Hellenic Corps Officers Military Academy cadets. Pure-tone audiograms were obtained on both ears. Participants were also subjected to diagnostic transient-evoked otoacoustic emissions (TEOAEs). Finally, they were all tested for efferent function through the suppression of TEOAEs with contralateral noise. Following baseline evaluation, all cadets fired 10 rounds using a 7.62 mm Heckler & Koch G3A3 assault rifle while lying down in prone position. Immediately after exposure to gunfire noise and no later than 10 h, all participants completed an identical protocol for a second time, which was then repeated a third time, 30 days later. Results: The data showed that after the firing drill, 280 participants suffered a temporary threshold shift (TTS) (468 ears), while in the third evaluation conducted 30 days after exposure, 142 of these ears still presented a threshold shift compared to the baseline evaluation [permanent threshold shift (PTS) ears]. A receiver operating characteristics curve analysis showed that OAEs amplitude is predictive of future TTS and PTS. The results were slightly different for the suppression of OAEs showing only a slight trend toward significance. The curves were used to determine cut points to evaluate the likelihood of TTS/PTS for OAEs amplitude in the baseline evaluation. Decision limits yielding 71.6% sensitivity were 12.45 dB SPL with 63.8% specificity for PTS, and 50% sensitivity were 12.35 dB SPL with 68.2% specificity for TTS. Conclusions: Interestingly, the above data yielded tentative evidence to suggest that OAEs amplitude is both sensitive and specific enough to efficiently identify participants who are particularly susceptible to hearing loss caused by impulse noise generated by firearms. Hearing conservation programs may therefore want to consider including such tests in their routine. As far as efferent strength is concerned, we feel that further research is due, before implementing the suppression of OAEs in hearing conservations programs in a similar manner.

Railway noise annoyance on the railway track in northwest slovakia.

Abstract: Introduction: This paper describes an assessment of noise caused by railway traffic in a large high-loaded railway track in Northwest Slovakia. Materials and Methods: The measurements of noise levels generated by trains passing through residential neighborhoods were taken. Noise maps were also calculated showing noise pollution generated by the train traffic. In addition, the annoyance level and sleep disturbance of residents affected by railway noise were evaluated by a validated questionnaire on a pilot sample of 107 respondents living near the important railway track. Results: The measurements indicated that the noise levels generated by the passage of the train were extremely high especially at night, clearly exceeding the nighttime limits of equivalent sound pressure level established by the Decree of the Slovak Ministry of Health (No.549/2007) (LAeq = 55 dB). Measurements at one point during the night exceeded the limit values of up to 17.4 dB. The residents reported feeling affected by the noise generated by passing trains, which caused irritability, headache, poor concentration, and insomnia. In addition, 19.64% of the residents claimed that nocturnal noise pollution was the most distressing. The results of bivariate analysis showed a higher risk of annoyance especially for railway noise [ORMH = 7.80 (4.02–15.14)] and the noise from industry [ORMH = 3.08 (1.72–5.50)] in the exposed location. Discussion: The effects of railway traffic on annoyance/sleep and psychosocial well-being were evaluated in a few studies. In accordance with our results the railway noise mostly disturbs sleep and rest of the respondents. Conclusion: The pilot survey showed the importance of sleep and rest disturbance by railway noise and the possibilities of getting worse health condition in the future. Noise abatement measures and strategies should, therefore, be implemented in an effective and manageable way increasing the environmental advantages of rail transport.

A methodology to objectively assess the performance of sound field amplification systems demonstrated using 50 physical simulations of classroom conditions.

Abstract: Introduction: The effect of a sound reinforcement system, in terms of speech intelligibility, has been systematically determined under realistic conditions. Different combinations of ambient and reverberant conditions representative of a classroom environment have been investigated. Materials and Methods: By comparing the measured speech transmission index metric with and without the system in the same space under different room acoustics conditions, it was possible to determine when the system was most effective. A new simple criterion, equivalent noise reduction (ENR), was introduced to determine the effectiveness of the sound reinforcement system which can be used to predict the speech transmission index based on the ambient sound pressure and reverberation time with and without amplification. Results: This criterion had a correlation, R2>0.97. It was found that sound reinforcement provided no benefit if the competing noise level was less than 40 dBA. However, the maximum benefit of such a system was equivalent to a 7.7 dBA noise reduction. Conclusion: Using the ENR model, it would be possible to determine the suitability of implementing sound reinforcement systems in any room, thus providing a tool to determine if natural acoustic treatment or sound field amplification would be of most benefit to the occupants of any particular room.

Cathodal neuromodulation of dominant temporoparietal cortex with transcranial direct current stimulation for tinnitus: A case series.

Abstract: There is scant literature on the effectiveness of using transcranial direct current stimulation (tDCS) as an intervention modality for managing tinnitus. The current case series reflects the use of tDCS as an effective intervention for tinnitus while inhibiting the dominant temporoparietal cortex and simultaneous stimulating the non-dominant dorsolateral prefrontal cortex.

Realizing modeling and mapping tools to study the upsurge of noise pollution as a result of open-cast mining and transportation activities

Abstract: Introduction: In open-cast mines, noise pollution has become a serious concern due to the extreme use of heavy earth moving machinery (HEMM). Materials and Methods: This study is focused to measure and assess the effects of the existing noise levels of major operational mines in the Keonjhar, Sundergadh, and Mayurbhanj districts of Odisha, India. The transportation noise levels were also considered in this study, which was predicted using the modified Federal Highway Administration (FHWA) model. Result and Discussion: It was observed that noise induced by HEMM such as rock breakers, jackhammers, dumpers, and excavators, blasting noise in the mining terrain, as well as associated transportation noise became a major source of annoyance to the habitants living in proximity to the mines. The noise produced by mechanized mining operations was observed between 74.3 and 115.2 dB(A), and its impact on residential areas was observed between 49.4 and 58.9 dB(A). In addition, the noise contour maps of sound level dispersion were demonstrated with the utilization of advanced noise prediction software tools for better understanding. Conclusion: Finally, the predicted values at residential zone and traffic noise are correlated with observed values, and the coefficient of determination, R2, was calculated to be 0.6891 and 0.5967, respectively.

Effect of systematic desensitization training on acceptable noise levels in adults with normal hearing sensitivity

Abstract: Context: The willingness of a person to accept noise while listening to speech can be measured using the acceptable noise level (ANL) test. Individuals with poor ANL are unlikely to become successful hearing aid users. Hence, it is important to enhance the individual’s ability to accept noise levels. The current study was an attempt to investigate whether systematic desensitization training can improve the ANL in individuals having high ANL. Aims: To investigate the effect of systematic desensitization training on ANLs in individuals with normal hearing sensitivity. Settings and Design: Observational study design. Materials and Methods: Thirty-eight normally hearing adults within the age range of 18–25 years participated in the study. Initially, baseline ANL was measured for all participants. Based on the baseline ANL, participants were categorized into three groups; low ANL, mid ANL, and high ANL. The participants with high ANL were trained using systematic desensitization procedure whereas, individuals with low and mid ANL did not undergo any training and served as the comparison groups. After the training period, ANL was measured again for all the participants. Statistical Analysis Used: Repeated measures of analysis of variance with follow up paired "t" test. Results: Analysis revealed a significant main effect of systematic desensitization training on ANL. There was a significant improvement in ANL in participants with high ANL. However, there was no significant difference in ANL between baseline and follow-up session in individuals with low and mid ANL. Conclusions: Systematic desensitization training can facilitate ANL, thereby enhancing the individual’s ability to accept the noise levels. This enhanced ANL can facilitate better hearing aid fitting and acceptance.

Examination of previously published data to identify patterns in the social representation of "Loud music" in young adults across countries

Abstract: Purpose: The current study was aimed at understanding the patterns in the social representation of loud music reported by young adults in different countries. Materials and Methods: The study included a sample of 534 young adults (18–25 years) from India, Iran, Portugal, United Kingdom, and United States. Participants were recruited using a convince sampling, and data were collected using the free association task. Participants were asked to provide up to five words or phrases that come to mind when thinking about “loud music.” The data were first analyzed using the qualitative content analysis. This was followed by quantitative cluster analysis and chi-square analysis. Results: The content analysis suggested 19 main categories of responses related to loud music. The cluster analysis resulted in for main clusters, namely: (1) emotional oriented perception; (2) problem oriented perception; (3) music and enjoyment oriented perception; and (4) positive emotional and recreation-oriented perception. Country of origin was associated with the likelihood of participants being in each of these clusters. Conclusion: The current study highlights the differences and similarities in young adults’ perception of loud music. These results may have implications to hearing health education to facilitate healthy listening habits.

Impact of uncertainties related to noise indicator determination on observed exposure-effect relationship.

Abstract: Context: Noise indicators are the basis to describe noise exposure–effect relationships. The assessment of these noise indicators in field studies includes various uncertainties, so that the true values differ from the determined values used for establishing curve fits. If the relationship between a noise indicator and its effect is nonlinear, uncertainties of the noise indicator modify the observed exposure–effect relationships. Materials and Methods: The determination of an exposure-relationship curve fit within a field study was simulated based on the assumption of a given true exposure-relationship without uncertainties and normal distributed uncertainties for the observed noise indicator used for the statistics. Results: In case of an upward curvature of the exposure–effect relationship, the uncertainty for the noise indicator value leads to an asymmetric effect for the curve fit. Uncertainties of the same amount of over- or underestimation will not result in an identical over- or underestimation of the observed effect. A simulation of this effect shows an increased curvature of the observed curve fit, with overestimated exposure–effect relationships. Conclusion: Although linear exposure–effect curves are not observed with a systematic shift, quadratic, cubic, and exponential curve forms include a systematic uncertainty in the presented exposure–response curve. If such curves are used to define threshold levels to limit harmful effects of noise, no further uncertainty margins are needed for those situations where the calculated noise indicator uncertainties are equal or lower than those present in the underlying field study.

Apoptosis in the cochlear nucleus and inferior colliculus upon repeated noise exposure

Abstract: The time course of apoptosis and the corresponding neuronal loss was previously shown in central auditory pathway of mice after a single noise exposure. However, repeated acoustic exposure is a major risk factor for noise-induced hearing loss. The present study investigated apoptosis by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) assay after a second noise trauma in the ventral and dorsal cochlear nucleus and central nucleus of the inferior colliculus. Mice [Naval Medical Research Institute (NMRI) strain] were noise exposed [115 dB sound pressure level, 5–20 kHz, 3 h) at day 0. A double group received the identical noise exposure a second time at day 7 post-exposure and apoptosis was either analyzed immediately (7-day group-double) or 1 week later (14-day group-double). Corresponding single exposure groups were chosen as controls. No differences in TUNEL were seen between 7-day or 14-day single and double-trauma groups. Interestingly, independent of the second noise exposure, apoptosis increased significantly in the 14-day groups compared to the 7-day groups in all investigated areas. It seems that the first noise trauma has a long-lasting effect on apoptotic mechanisms in the central auditory pathway that were not largely influenced by a second trauma. Homeostatic mechanisms induced by the first trauma might protect the central auditory pathway from further damage during a specific time slot. These results might help to understand the underlying mechanisms of different psychoacoustic phenomena in noise-induced hearing loss.

Advanced noise-induced deafness among workers in singapore - what has changed?

Abstract: Context: Noise-induced deafness (NID) contributes a significant disease burden internationally, and is a leading occupational disease in Singapore. Aims: This study profiles the epidemiological characteristics of advanced noise-induced deafness (NID(A)) cases and explores whether these have evolved with time. Settings and Design: A quantitative retrospective analysis of prior NID(A) cases was performed. National records of NID(A) cases from 2001 to 2010 were obtained, with permission from the Ministry of Manpower, consisting of worker audiograms, case records, and noise monitoring reports. Methods and Material: Comparison was made with data from a prior study (127 cases, 1985–1994) to identify shifts in NID(A) epidemiology; 71 out of 73 NID(A) case records (2001–2010) from the national data were reviewed. Statistical Analysis Used: Statistical Package for Social Sciences (IBM) was used for statistical analysis. Results: Mean noise exposure (24–29.6 years) and age at diagnosis (48–54.6 years) have risen. Total case numbers (127 to 73 cases), average hearing loss levels (61.5 to 56.0 A-weighted decibels), and delayed reporting of NID(A) cases (82.7% to 47.9%) have decreased. Metal manufacturing and marine industries remain top contributors (69.1%, from 68.5%); 31% were noncompliant with hearing protector (personal protective equipment, PPE) use and 38% did not use PPE properly. Conclusions: NID(A) case profiles have shifted over time, with reduced case numbers, lower hearing loss levels at diagnosis, and earlier case notification, possibly linked to improvements in legislative coverage and NID prevention programs. Changes in age and average duration of noise exposure may be related to these improvements. Early case notification, PPE compliance, and proper usage should be focus areas for NID prevention and hearing conservation programs.

Evaluation of Effect of Garlic Aged Extracts and Vitamin B12 on Noise-Induced Hearing Loss

Abstract: Objective: This study investigated effects of S-allylmercaptocysteine (SAMC), diallyl disulfide (DADS), and vitamin B12 on inner ear functions and morphology after long-period high-level broadband noise exposure. Materials and Methods: Twenty-four healthy rats were randomly divided into four groups. First group was chosen as the control group. Vitamin B12, SAMC, and DADS were applied to other groups for 4 weeks. On the 14th day, each group was exposed to broadband noise. Auditory brainstem response test was performed before and immediately after noise exposure and repeated on the 2nd and 14th day. Results: Permanent threshold shifts were significantly lower in groups treated with vitamin B12, SAMC, and DADS. Histologically, cochleae of SAMC and DADS groups were found to be better preserved than the cochleae of vitamin B12 and control groups. Conclusion: Physiologically and histologically, SAMC and DADS reduced the long-term effects of noise. However, physiological recovery was not consistent with the morphological findings in vitamin B12 group.