Noise-induced hearing loss in children: A 'less than silent' environmental danger

The effect of screen time on hearing and balance in 6-16 aged children

BACKGROUND

The increase in screen time and the decrease in physical- activity cause balance problems as well as many systemic handicaps.

AIMS/OBJECTIVES

This study aimed to determine the effect of screen time on balance and the effect of headphone usage time on hearing.

METHOD

Thirty-four individuals aged 6-16 years who applied to our clinic with complaints of dizziness and/or balance disorder were included in the study. Participants were divided into 2 groups according to their screen time: Group 1 (4-8 h/day) and Group2(>8 h/day). The other two groups are grouped according to headphone usage time as Group A (2-4 h/day) and Group B (>4hours/day). Pure-tone audiometry, extended high frequency-audiometry, Videonystagmography (VNG) and Computerized Dynamic Posturography (CDP) tests and Pediatric Berg Balance Scale and Visual Analogue Scale were applied to all individuals. CDP scores and pure tone hearing thresholds between groups were compared.

RESULTS

A significant difference was observed between Group 1 and Group 2 according to the CDP test (visual, vestibular and composite scores), and according to the VAS-dizziness and PBS (p ≤ .05). Pure tone average and pure tone thresholds at high frequencies were compared between Group A and Group B according to headphone usage time. Pure tone thresholds of Group B were worse at high frequencies than Group A (p ≤ .05).

CONCLUSIONS

It has been observed that prolonged screen time may cause balance impairment in children and prolonged use of headphones may affect high-frequency hearing thresholds.

Dangerous Decibels Program in Elementary and Middle School Students: Effectiveness After a 6-Month Follow-Up

PURPOSE

The purpose of this article was to assess the effectiveness of the Dangerous Decibels (DD) program in students in the short- and medium-term follow-ups (up to 6 months), including an online game.

METHOD

A randomized trial was conducted between two interventions (DD and placebo). The research included 58 participants who were divided into two groups: the study group (SG) and the control group. The following phases were developed: intervention (DD or placebo), post-3-month assessment and availability of the online game, and post-6-month assessment. A questionnaire was administered to assess their performance. Overall total scores and category scores were obtained.

RESULTS

Improved overall scores were found in the SG in the immediate post-intervention (p = .004), post-3-month (p = .022), and post-6-month (p = .002) questionnaires, as well as the knowledge and behavior categories.

CONCLUSIONS

The DD program effectively improved the knowledge and behavior of 10- to 12-year-old children regarding noise in the short- and medium-term follow-ups. However, no significant changes were achieved in terms of barriers only by using the program and the online game. Adding a second intervention (the online game) to the program seems to be a good option to maintain the changes achieved with the interactive class.

Prevalence and global estimates of unsafe listening practices in adolescents and young adults: a systematic review and meta-analysis

INTRODUCTION

This study aimed to determine the prevalence of unsafe listening practices from exposure to personal listening devices (PLDs) and loud entertainment venues in individuals aged 12-34 years, and to estimate the number of young people who could be at risk of hearing loss from unsafe listening worldwide.

METHODS

We conducted a systematic review and meta-analysis to estimate the prevalence of unsafe listening practices from PLDs and loud entertainment venues. We searched three databases for peer-reviewed articles published between 2000 and 2021 that reported unsafe listening practices in individuals aged 12-34 years. Pooled prevalence estimates (95% CI) of exposed populations were calculated using random effects models or ascertained from the systematic review. The number of young people who could be at risk of hearing loss worldwide was estimated from the estimated global population aged 12-34 years, and best estimates of exposure to unsafe listening ascertained from this review.

RESULTS

Thirty-three studies (corresponding to data from 35 records and 19 046 individuals) were included; 17 and 18 records focused on PLD use and loud entertainment venues, respectively. The pooled prevalence estimate of exposure to unsafe listening from PLDs was 23.81% (95% CI 18.99% to 29.42%). There was limited certainty (p>0.50) in our pooled prevalence estimate for loud entertainment venues. Thus, we fitted a model as a function of intensity thresholds and exposure duration to identify the prevalence estimate as 48.20%. The global estimated number of young people who could be at risk of hearing loss from exposure to unsafe listening practices ranged from 0.67 to 1.35 billion.

CONCLUSIONS

Unsafe listening practices are highly prevalent worldwide and may place over 1 billion young people at risk of hearing loss. There is an urgent need to prioritise policy focused on safe listening. The World Health Organization provides comprehensive materials to aid in policy development and implementation.

Establishing Healthy Lifestyle Choices Early: How to Counsel Children and Their Parents

Promoting childhood and adolescent health and long-term well-being requires an emphasis on preventative care and anticipatory guidance. In this review, the authors will focus on pertinent ear, nose, and throat preventative health in children, providing clinicians with relevant and succinct information to counsel children and their parents on the following essential subjects: foreign body aspiration and ingestion, upper respiratory infection prevention, noise exposure risks, aural hygiene, risks of primary and secondhand smoke exposure, and sleep hygiene.

Sexual Dimorphism in the Functional Development of the Cochlear Amplifier in Humans

OBJECTIVES

Otoacoustic emissions, a byproduct of active cochlear mechanisms, exhibit a higher magnitude in females than in males. The relatively higher levels of androgen exposure in the male fetus are thought to cause this difference. Postnatally, the onset of puberty is also associated with the androgen surge in males. In this study, we investigated sexual dimorphism in age-related changes in stimulus-frequency otoacoustic emissions for children.

DESIGN

In a retrospective design, stimulus-frequency otoacoustic emissions were analyzed from a cross-sectional sample of 170 normal-hearing children (4 to 12 years) and 67 young adults. Wideband acoustic immittance and efferent inhibition measures were analyzed to determine the extent to which middle ear transmission and efferent inhibition can account for potential sex differences in stimulus-frequency otoacoustic emissions.

RESULTS

Male children showed a significant reduction in otoacoustic emission magnitudes with age, whereas female children did not show any such changes. Females showed higher stimulus-frequency otoacoustic emission magnitudes compared with males. However, the effect size of sex differences in young adults was larger compared with children. Unlike the otoacoustic emission magnitude, the noise floor did not show sexual dimorphism; however, it decreased with age. Neither the wideband absorbance nor efferent inhibition could account for the sex differences in stimulus-frequency otoacoustic emissions.

CONCLUSIONS

The cochlear-amplifier function remains robust in female children but diminishes in male children between 4 and 12 years of age. We carefully eliminated lifestyle, middle ear, and efferent factors to conclude that the androgen surge associated with puberty likely caused the observed masculinization of stimulus-frequency otoacoustic emissions in male children. These findings have significant theoretical consequences. The cochlea is considered mature at birth; however, the present findings highlight that functional cochlear maturation, as revealed by otoacoustic emissions, can be postnatally influenced by endogenous hormonal factors, at least in male children. Overall, work reported here demonstrates sexual dimorphism in the functional cochlear maturational processes during childhood.

Leisure Noise Exposure and Associated Health-Risk Behavior in Adolescents: An Explanatory Study among Two Different Educational Programs in Flanders

Adolescents frequently engage in noisy leisure activities which can result in hearing-related problems. However, the effect of leisure noise exposure is liable to an individual's risk-taking behavior. Identifying leisure noise activities and relevant factors related to risk-taking behavior in adolescents, are important to optimize hearing conservation programs targeting youngsters. The purpose of the study was to explore the presence of hearing-related symptoms, as well as noise exposure during various activities, and the use of hearing protector devices (HPDs) in adolescents in two educational programs in Flanders. In addition, their attitudes and beliefs towards noise, hearing loss, and HPDs were investigated. The final sample consisted of 247 adolescents. The most important hearing-related symptoms after noise exposure were tinnitus and noise sensitivity. With regard to leisure noise exposure, listening to PMPs was most frequently reported. The use of HPDs during most noisy activities was limited, in accordance with the presence of hearing-related symptoms, considering noise as unproblematic, and having worse scores on subscales of the beliefs about hearing protection and hearing loss scale. In the future, hearing conservation programs should target adolescents specifically for a more health-orientated behavior towards noise exposure, hearing loss, and HPDs.

Hearing and Exposure to Music in Adolescents From Four Schools of Córdoba, Argentina

Purposes The aims of this study are (a) to characterize the hearing of adolescents from four schools of Córdoba, Argentina, through the analysis of conventional and extended high-frequency audiometric thresholds and otoacoustic emissions (OAEs) and (b) to analyze the association between the mentioned hearing tests and exposure to music. Method It was a cross-sectional correlational descriptive study. Hearing thresholds (250-16000 Hz), transient evoked OAEs, and distortion product OAEs were evaluated in 225 adolescents (450 ears) aged 14 and 15 years. The ears were split into two groups: Group 1 had thresholds ≤ 21 dB HL in all frequencies, and Group 2 had thresholds > 21 dB HL in at least one. Exposure to music was evaluated through a questionnaire. Results Statistically significant differences were found in both ears between Groups 1 and 2. A notch at 3000-6000 Hz was noted in both groups. Group 2 showed a progressive threshold increase from 9000 Hz. Amplitude decrease, negative values, absent distortion product OAEs, and transient evoked OAEs were noted even in Group 1. A statistically significant association between Groups 1 and 2 and the presence/absence of OAEs was observed in most frequencies. Ears with moderate or high exposure to music had greater hearing thresholds compared to ears with low exposure at most frequencies; this was more evident in Group 1. Regarding exposure to music and OAEs, no significant differences were found between the exposure categories. Conclusions The findings highlight the value of implementing hearing conservation programs in Argentina, analyzing hearing tests correlated with questionnaires about recreational noise exposure in order to detect vulnerable ears early.

Sound-level Monitoring Earphones With Smartphone Feedback as an Intervention to Promote Healthy Listening Behaviors in Young Adults

OBJECTIVES

More than a billion adolescents and youngsters are estimated to be at risk of acquiring recreational noise-induced hearing loss (RNIHL) due to the unsafe use of personal audio systems. RNIHL is preventable; therefore, the present study aimed to determine (i) the accuracy and reliability of dbTrack (Westone) sound-level monitoring earphones and (ii) the effect of sound-level monitoring earphones with smartphone feedback and hearing-health information as an intervention to promote healthy listening behaviors in young adults.

DESIGN

The study consisted of two phases: the first phase investigated the accuracy and reliability of dbTrack sound-level monitoring earphones. Accuracy was determined by comparing earphone measurements to sound level meter measurements. Intradevice reliability was determined by comparing earphone measurements during test-retest conditions. Nineteen participants were recruited through convenience sampling to determine within-subject reliability by comparing in-ear sound levels measured by the earphones during test-retest conditions. For the second phase of the study, a single-group pretest-posttest design was utilized. Forty participants, recruited through snowball sampling, utilized the sound-level monitoring earphones with the accompanying dbTrack smartphone application for 4 weeks. The application's smartphone feedback was disabled during the first 2 weeks (pretest condition) and enabled during the last 2 weeks (posttest condition). Average daily intensities, durations, and sound dosages measured during pre- and posttest conditions were compared.

RESULTS

Phase 1 dbTrack earphone measurements were within 1 dB when compared with sound level meter measurements. Earphones were also within 1 dB in repeated measures across earphones and across participants. Phase 2 posttest average daily intensity decreased by 8.7 dB (18.3 SD), duration decreased by 7.6 minutes (46.6 SD), and sound dose decreased by 4128.4% (24965.5% SD). Differences in intensity and sound dose were significantly lower with a small and medium effect size, respectively.

CONCLUSIONS

This study's preliminary data indicate that dbTrack (Westone) sound-level monitoring earphones with a calibrated in-ear microphone can reliably and accurately measure personal audio systems sound exposure. Preliminary results also suggest that feedback on sound exposure using the accurate sound-level monitoring earphones with the accompanying dbTrack application can potentially promote safe listening behavior in young adults and reduce the risk of acquiring an RNIHL.

A smartphone application to objectively monitor music listening habits in adolescents : Personal listening device usage and the accuracy of self-reported listening habits

Background

Listening to music through personal listening devices (PLDs) has become more prevalent during last decades. The aim of this study was to evaluate music listening habits through PLDs in adolescents with a smartphone application, and to assess the accuracy of self-reported listening habits.

Methods

This study was embedded in the Generation R Study, a population-based prospective birth cohort in Rotterdam, the Netherlands. A smartphone application for Android operating systems was developed to objectively monitor music listening habits for a period of 35 days. A postal questionnaire was used to subjectively assess listening habits. The level of agreement between the objectively measured and self-reported listening habits were evaluated using weighted kappa coefficients. Data were collected from May 2017 to March 2019.

Results

A total of 311 adolescents aged 12 to 15 years were included, of whom 237 (76.2%) completed the postal questionnaire. The results of the smartphone application showed that the median listening frequency was 2.1 days a week (IQR 1.0–3.4), the median listening time 21.1 min a day (IQR 9.1–53.7), and the mean listening level 54.5% (SD 18.1%). There was a slight to fair agreement between the objectively measured, and self-reported listening habits according to the weighted kappa coefficients (k = 0.179 to 0.364).

Conclusions

The results of the current study suggest that self-reported measures of listening habits are not always accurate. We consider a smartphone application to monitor listening habits of added value in future research investigating the possible damaging effects of PLDs on hearing acuity.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40463-020-00488-5.

Associations between adolescents' earphone usage in noisy environments, hearing loss, and self-reported hearing problems in a nationally representative sample of South Korean middle and high school students

Few epidemiological studies have examined the relationship between earphone usage and hearing loss in adolescents. This study identified the prevalence of hearing loss in South Korean adolescents using representative national survey data and evaluated the relationship between earphone usage in a noisy environment and hearing loss. This study analyzed 532 subjects (12-19 years) who participated in a 2012 national survey and completed health and noise environment exposure questionnaires and pure tone audiometry (PTA) test. Hearing loss was defined as an average hearing threshold of 26 Decibel-A (dBA) or higher in PTA. The relationship between earphone usage and hearing loss was analyzed using a hierarchical logistic regression model. Adolescents who were exposed to high noise levels via headphones in a noisy environment had a hearing loss prevalence of 22.6% and adolescents who used earphones 80 minutes or more per day on average had the hearing loss prevalence of 22.3%. The results of the logistic regression analysis revealed that adolescents who used earphones in a noisy environment had a 4.5-fold higher risk of hearing loss and an 8.4 times higher risk of having a subjective hearing problem than those who did not use earphones (prevalence odds ratio (pOR) = 4.54, 95% confidence interval (CI): 1.35-15.24; pOR = 8.39, 95% CI: 1.12-62.83, respectively). Additionally, adolescents who used earphones more than 80 minutes per day in a noisy environment had a 4.7 times higher risk of hearing loss than those who used them less than 80 minutes per day (pOR = 4.68, 95% CI: 1.08-20.22). Longitudinal studies are needed to provide evidence of causality between earphone usage and hearing loss.

Personal Music Players Use and Other Noise Hazards among Children 11 to 12 Years Old

Exposure to loud music-due to widespread personal music players (PMPs) and noisy leisure activities-are major risk factors for noise induced hearing loss (NIHL) in adolescents. However, there is little evidence of the impact of noise on the hearing of younger children. This study aimed to explore an association between PMP use and hearing, and to identify other sources of noise among children. The study sample consisted of 1032 children aged 11-12 years old. Hearing thresholds were determined from 0.5 to 8 kHz. PMP use and other noise exposures were evaluated using a survey. We found that 82% of the children had a PMP, and 78% were exposed to noise when playing computer games. An audiometric notch was documented in 1.3% of the children. Only 11.5% of the children ever used hearing protection while engaged in noisy activities. We found no convincing evidence of an association between PMP use and hearing thresholds, although our results suggest that tinnitus may be an early sign of NIHL in young children. The study shows a need to provide children, their parents, and educators with knowledge of how to take care of hearing, including how to avoid and minimize noise exposure.

Children who say hand dryers 'hurt my ears' are correct: A real-world study examining the loudness of automated hand dryers in public places

Introduction

Previous research has suggested that hand dryers may operate at dangerously loud levels for adults. No research has explored whether they operate at a safe level for children's hearing. Children's ears are more sensitive to damage from loud sounds than adult ears. Health Canada prohibits the sale of toys with peak loudness greater than 100 dB. This study tested installed dryers in public washrooms to see if they were safe for children's hearing.

Methods

Forty-four hand dryers in public washrooms were each measured for peak sound levels in a standardized fashion, including at children's ear canal heights. Each dryer was measured at 10 different combinations of heights and distances from the wall, and with and without hands in the air stream coming from the hand dryer, for a total of 20 measurements per dryer.

Results

Xlerator units performed the loudest, with all being louder than 100 dBA at all measurements whenever hands were in the airstream. Several Dyson Airblade models were also very loud, including the single loudest measurement of 121 dBA. While some other units operated at low sound levels, many units were louder at children's ear heights than at adult ear heights.

Discussion

Many dryers operated much louder than their manufacturers claimed, usually greater than 100 dBA (the maximum allowable noise level for products/toys meant for children).

Conclusion

This study suggests that many hand dryers operate at levels far louder than their manufacturers claim and at levels that are clearly dangerous to children's hearing.

Noise exposure limit for children in recreational settings: Review of available evidence

It is universally recognized that prolonged exposure to high levels of non-impulsive noise will lead to noise-induced hearing loss. These high levels of noise have traditionally been found in an occupational setting, but exposure to high levels of noise is increasingly common in recreational settings. There is currently no established acceptable risk of hearing loss in children. This review assumed that the most appropriate exposure limit for recreational noise exposure in children would be developed to protect 99% of children from hearing loss exceeding 5 dB at the 4 kHz audiometric test frequency after 18 years of noise exposure. Using the ISO 1999:2013 model for predicting hearing loss, it was estimated that noise exposure equivalent to an 8-h average exposure (L_EX) of 82 dBA would result in about 4.2 dB or less of hearing loss in 99% of children after 18 years of exposure. The 8-h L_EX was reduced to 80 dB to include a 2 dB margin of safety. This 8-h L_EX of 80 dBA is estimated to result in 2.1 dB or less of hearing loss in 99% of children after 18 years of exposure. This is equivalent to 75 dBA as a 24-h equivalent continuous average sound level.

Increased incidence in hospitalised patients with sudden sensorineural hearing loss: a 14-year nationwide population-based study

Objective: To conduct a 14-year nationwide study on the epidemiologic incidence in patients with sudden sensorineural hearing loss (SSNHL). Design: Retrospective cross-sectional design. Study sample: Data of patients hospitalised with the diagnosis of SSNHL from 2000 to 2013, extracted from the Taiwan National Health Insurance Research Database. Results: In total, 31,258 patients were included. The mean age was 50.30 ± 16.70 years. Males (53.5%) were more commonly diagnosed with SSNHL than females (46.5%). The patients most commonly presented with SSNHL were in the age group of 45-64 years. The crude incidence of SSNHL from 2000 to 2013 was 9.76 per 100,000 people per year. The annual incidence rate shows a steady increased from 5.15 in 2000 to 13.97 per 100,000 people in 2013 with a statistical significance (p < 0.001). Conclusion: This 14-year nationwide study indicated an increased incidence rate of SSNHL. This necessitates the development of additional treatment modalities to enhance the prognosis and the clarification of the underlying mechanism of this enigmatic disease.

Early Indication of Noise-Induced Hearing Loss in Young Adult Users of Personal Listening Devices

Objectives:

The recent integration of portable music players into cell phones has further increased the use of personal listening devices (PLD) among young adults, raising concerns about potentially hazardous effects on hearing.

Methods:

Assessment of young adults’ hearing ability and listening preferences by subjective and objective measurement. Young adult users of PLDs (n = 50; 30 females, 20 males; mean age = 24.1 ± 4.2 years; average PLD use = 6.1 ± 2.1 years) were included. Subjective assessment of listening preferences was performed via a questionnaire as well as objective assessment of preferred volume levels in different background noise environments and hearing tests.

Results:

Preferred volume levels were significantly correlated with hearing thresholds. Most participants exhibited safe listening behavior according to National Institute for Occupational Safety and Health criteria. We identified a substantial high-risk subgroup of PLD users (22% of participants, daily use ⩾2 h at ⩾91 dB) in which pure tone audiometry showed increased hearing thresholds at 4000 and 6000 Hz, potentially indicating an early manifestation of noise-induced hearing loss (NIHL).

Conclusions:

These findings suggest that preventive measures may be warranted to prevent a future increase of clinically relevant NIHL among heavy users of PLDs.

Headphone listening habits and hearing thresholds in swedish adolescents

Introduction:

The aim of this study was to investigate self-reported hearing and portable music listening habits, measured hearing function and music exposure levels in Swedish adolescents. The study was divided into two parts.

Materials and Methods:

The first part included 280 adolescents, who were 17 years of age and focused on self-reported data on subjective hearing problems and listening habits regarding portable music players. From this group, 50 adolescents volunteered to participate in Part II of the study, which focused on audiological measurements and measured listening volume.

Results:

The results indicated that longer lifetime exposure in years and increased listening frequency were associated with poorer hearing thresholds and more self-reported hearing problems. A tendency was found for listening to louder volumes and poorer hearing thresholds. Women reported more subjective hearing problems compared with men but exhibited better hearing thresholds. In contrast, men reported more use of personal music devices, and they listen at higher volumes.

Discussion:

Additionally, the study shows that adolescents listening for ≥3 h at every occasion more likely had tinnitus. Those listening at ≥85 dB L_{Aeq, FF} and listening every day exhibited poorer mean hearing thresholds, reported more subjective hearing problems and listened more frequently in school and while sleeping.

Conclusion:

Although the vast majority listened at moderate sound levels and for shorter periods of time, the study also indicates that there is a subgroup (10%) that listens between 90 and 100 dB for longer periods of time, even during sleep. This group might be at risk for developing future noise-induced hearing impairments.

Perceptions of public primary school teachers regarding noise-induced hearing loss in South Africa

Background

Noise-induced hearing loss (NIHL) is an increasingly growing problem in young children. This is attributed to recreational noise being the most common cause of this problem. In young children, hearing problems can delay language development and reduce academic achievements. South Africa, in particular, has limited information and protective measures regarding the conservation of hearing in school-aged children.

Objectives

The main aim of the study was to determine the perception of primary school teachers regarding NIHL. The study also aimed to determine if any hearing conservation programmes are being implemented in schools and the need for training of primary school teachers regarding NIHL.

Method

A survey was conducted. In order to cover the population of interest, the sampled schools in Pretoria were clustered into urban, semi-urban and rural areas.

Results

The majority of the teachers included in this study are aware of NIHL and its effects. They, however, lack the necessary resources and knowledge to effectively use this information. Most (67.5%) of the teachers indicated that they have never been exposed to children with NIHL in a school setting. It was also found that the majority (84%) of the schools included in the study do not implement hearing screening and conservation programmes.

Conclusion

Although the sample size was limited, the results correlate with other research in this field indicating a need for planning and implementation of hearing conservation programmes in schools, including training of teachers in order for these programmes to be effective.

Influence of Hearing Risk Information on the Motivation and Modification of Personal Listening Device Use

PURPOSE

The purpose of this study was (a) to investigate the behaviors, knowledge, and motivators associated with personal listening device (PLD) use and (b) to determine the influence of different types of hearing health risk education information (text with or without visual images) on motivation to modify PLD listening use behaviors in young adults.

METHOD

College-age students (N = 523) completed a paper-and-pencil survey tapping their behaviors, knowledge, and motivation regarding listening to music or media at high volume using PLDs. Participants rated their motivation to listen to PLDs at lower volume levels following each of three information sets: text only, behind-the-ear hearing aid image with text, and inner ear hair cell damage image with text.

RESULTS

Acoustically pleasing and emotional motives were the most frequently cited (38%-45%) reasons for listening to music or media using a PLD at high volume levels. The behind-the-ear hearing aid image with text information was significantly (p < .0001) more motivating to participants than text alone or the inner ear hair cell damage image with text.

CONCLUSIONS

Evocative imagery using hearing aids may be an effective approach in hearing protective health campaigns for motivating safer listening practices with PLDs in young adults.

Educating teenagers about hearing health by training them to educate children

OBJECTIVE

We investigated the change in hearing-health behaviour amongst teenagers trained to deliver the Dangerous Decibels programme to younger children.

DESIGN

The Dangerous Decibels programme uses a two-stage process to train 8-12 year-old children to protect their hearing from noise: (1) a team of experts train 'Educators' who (2) give classroom training to children in schools. Training teenagers as Educators may add a second level of benefit if teenagers internalize the hearing-health messages that they present and thus protect their own hearing better. They were assessed before training, immediately after, and three months later (after all had presented the classroom training) using a questionnaire. In addition, a focus group was conducted with a subgroup of the Educators to assess their subjective experience.

STUDY SAMPLE

We trained 44 Educators aged 14-17 years.

RESULTS

Results were generally positive: there were significant and sustained improvements in knowledge, self-reported behaviour, and perceived supports towards protecting hearing, and trends but not significant changes in attitudes or perceived barriers to hearing protection.

CONCLUSIONS

Providing training to teenagers had benefits beyond the delivery of training to younger children, but improvements in the delivery model may increase the uptake and impact on the teenagers.

Efeitos do mp3 player na audição

Objetivo investigar se há dano e a extensão do mesmo com o uso de MP3 player. Métodos aplicação do exame de Emissões Otoacústicas por Produto de Distorção e Emissões Otoacústicas Transientes, em 30 indivíduos expostos ao MP3 Player, sendo 15 deles no grupo controle (intensidade média de 85 dBNA) e 15 no grupo análise (intensidade média de 110 dBNA), ambos expostos por 15 minutos. O método utilizado para análise estatística foi inferencial (teste “t” para amostras pareadas). Resultados o grupo controle apresentou alteração na frequência de 1,5kHz nas Emissões Otoacústicas Transientes e na frequência de 6kHz no Produto de Distorção. Enquanto o grupo análise apresentou alteração nas frequências de 2, 3, 4kHz e na amplitude média de todas as frequências, nas Emissões Otoacústicas Transientes e nas frequências de 3 e 6kHz na Produto de Distorção. Conclusão o estudo mostrou que pessoas expostas a ruídos intensos, sendo o aparelho de MP3 Player fonte deste estudo, apresentam diminuição significante da amplitude, que indica alteração temporária das células da cóclea, podendo tornar-se uma lesão permanente caso a exposição seja contínua.

Variability of state school-based hearing screening protocols in the United States

The prevalence of hearing loss has increased among United States children. As schools commonly perform hearing screens, we sought to contrast current United States school-based hearing screening protocols. State department of health and education websites were reviewed to assess school hearing screening protocols for the fifty states and the District of Columbia. Individuals listed on these websites were contacted as necessary to confirm and/or acquire relevant data. School-based hearing screening is currently required in 34/51 (67 %) states. Of these 34 states, 28 (82 %) mandate grades for screening, but only 20 (59 %) require screening beyond 6th grade. Pure tone audiometry is the most common screening method (33/34 [97 %]). A majority of states screen at 1, 2 and 4 kHz usually at 20 or 25 dB hearing level. Six states recommend or require testing at 6 or 8 kHz, which is necessary to detect high-frequency hearing loss. The results indicate that United States school-based hearing screens vary significantly. They focus on low frequencies with few testing adolescents for whom high-frequency hearing loss has increased. Disparities in hearing loss detection are likely, particularly considering the evolution of hazardous noise exposures and rising prevalence of hearing loss.

Indoor environment and children's health: recent developments in chemical, biological, physical and social aspects

Much research is being carried out into indoor exposure to harmful agents. This review focused on the impact on children's health, taking a broad approach to the indoor environment and including chemical, microbial, physical and social aspects. Papers published from 2006 onwards were reviewed, with regards to scientific context. Most of publications dealt with chemical exposure. Apart from the ongoing issue of combustion by-products, most of these papers concerned semi volatile organic compounds (such as phthalates). These may be associated with neurotoxic, reprotoxic or respiratory effects and may, therefore, be of particular interest so far as children are concerned. In a lesser extent, volatile organic compounds (such as aldehydes) that have mainly respiratory effects are still studied. Assessing exposure to metals is still of concern, with increasing interest in bioaccessibility. Most of the papers on microbial exposure focused on respiratory tract infections, especially asthma linked to allergens and bio-aerosols. Physical exposure includes noise and electromagnetic fields, and articles dealt with the auditory and non auditory effects of noise. Articles on radiofrequency electromagnetic fields mainly concerned questions about non-thermal effects and papers on extremely low-frequency magnetic fields focused on the characterization of exposure. The impact of the indoor environment on children's health cannot be assessed merely by considering the effect of these different types of exposure: this review highlights new findings and also discusses the interactions between agents in indoor environments and also with social aspects.

Survey of high school students' perceptions about their iPod use, knowledge of hearing health, and need for education

PURPOSE

High school students' knowledge about hearing health and their perceptions of how they use personal listening devices (PLDs) including iPods were surveyed to determine the need, content, and preferred format for educational outreach to them.

METHOD

This study was a descriptive convenience survey of students at a California high school. An 83-item questionnaire was administered in December 2009 to assess students' demographics, knowledge of hearing health, perceived iPod use, and risk activities.

RESULTS

The response rate was 56%. Most of the students perceived that they used iPods safely. However, responses indicated that many of the respondents could be at risk of injury to themselves or others if they became unaware of their surroundings while listening to iPods. Some students were knowledgeable about hearing health and safe iPod use, but most needed information about hearing loss and hearing conservation.

CONCLUSION

Most of the students needed education (e.g., via health classes or the Internet) about hearing health, the warning signs of hearing loss, and how to prevent hearing loss. Resources for educational audiologists are provided.

Acoustic noise induces attention shifts and reduces foraging performance in three-spined sticklebacks (Gasterosteus aculeatus)

Acoustic noise is known to have a variety of detrimental effects on many animals, including humans, but surprisingly little is known about its impacts on foraging behaviour, despite the obvious potential consequences for survival and reproductive success. We therefore exposed captive three-spined sticklebacks (Gasterosteus aculeatus) to brief and prolonged noise to investigate how foraging performance is affected by the addition of acoustic noise to an otherwise quiet environment. The addition of noise induced only mild fear-related behaviours--there was an increase in startle responses, but no change in the time spent freezing or hiding compared to a silent control--and thus had no significant impact on the total amount of food eaten. However, there was strong evidence that the addition of noise increased food-handling errors and reduced discrimination between food and non-food items, results that are consistent with a shift in attention. Consequently, noise resulted in decreased foraging efficiency, with more attacks needed to consume the same number of prey items. Our results suggest that acoustic noise has the potential to influence a whole host of everyday activities through effects on attention, and that even very brief noise exposure can cause functionally significant impacts, emphasising the threat posed by ever-increasing levels of anthropogenic noise in the environment.

High frequency hearing sensitivity in adolescent females of a lower socioeconomic status over a period of 24 years (1985-2008)

PURPOSE

To examine annually over a period of 24 years, the high frequency hearing sensitivity in different groups of urban female adolescents with a low socioeconomic status (SES) and residential foster care.

METHODS

Hearing screening (15 decibel [dB] hearing level ranging from 1,000 to 8,000 Hertz [Hz]) and threshold (>15 dB hearing level) records were obtained from 8,710 female adolescents (mean age, 15.8 years [range, 12-20 years]), predominantly Hispanic and African American from households with a low SES. Data related to the use of personal listening devices (PLDs), daily hours of usage, occurrence of tinnitus, and hearing thresholds between 1,000 and 8,000 Hz over an 8-year period (2001-2008) were obtained from the adolescents.

RESULTS

High frequency hearing loss (HFHL) doubled over the 24-year period from 10.1% in 1985 to 19.2% in 2008. In comparison with the general adolescent population, this group of female adolescents presented with a higher percentage of bilateral mild or greater degrees of HFHL at two or more frequencies including 3,000, 4,000, and 6,000 Hz. Use of PLDs increased four-fold, from 18.3% (n = 68) in 2001 to 76.4% (n = 227) in 2008. Of the total number reporting tinnitus (n = 286), 99.7% (n = 285) also reported regular PLD use. A significant relationship was found between PLD use and reported tinnitus and HFHL irrespective of time of use of PLD.

CONCLUSIONS

Increased incidence of HFHL, reported tinnitus, PLD use, and hours of daily use in at-risk female adolescents of a low SES was found. A frequency interval of 3,000-6,000 Hz should be included in hearing screening protocols to identify potentially disabling hearing loss. Hearing conservation strategies need to be developed and/or modified that target and reach at-risk children and adolescents.

Prevalence of noise-induced hearing-threshold shifts and hearing loss among US youths

OBJECTIVE

We investigated trends in noise-induced threshold shifts (NITSs), high-frequency hearing loss (HFHL), and low-frequency hearing loss (LFHL).

METHODS

A total of 4310 adolescents 12 to 19 years of age completed audiometric testing during National Health and Nutrition Examination Surveys in 1988-1994 and 2005-2006. NITS criteria were audiometric patterns of decreased 3- to 6-kHz thresholds but preserved 0.5- to 1-kHz and 8-kHz thresholds; HFHL and LFHL criteria were high and low pure-tone averages, respectively, of >15 dB HL.

RESULTS

There were no significant increases in NITSs (odds ratio [OR]: 0.81 [95% confidence interval [CI]: 0.53-1.22]; P = .29), HFHL (OR: 1.21 [95% CI: 0.87-1.69]; P = .25), or LFHL (OR: 1.37 [95% CI: 0.77-2.45]; P = .28) between survey periods. However, a significant increase in the prevalence of NITSs occurred among female youths (11.6% [95% CI: 9.0%-14.1%] vs 16.7% [95% CI: 13.2%-20.3%]; P < .0001). The overall prevalence of exposure to loud noise or listening to music through headphones in the previous 24 hours increased from 19.8% (95% CI: 17.6%-22.1%) to 34.8% (95% CI: 31.0%-38.5%; P < .0001). In 2005-2006, female youths had a similar prevalence of exposure to recreational noise (23.6% [95% CI: 19.6%-27.6%] vs 27.7% [95% CI: 23.6%-31.8%]; P < .0001) and a lower prevalence of hearing-protection use (3.4% [95% CI: 1.6%-5.3%] vs 10.3% [95% CI: 7.3%-13.2%]; P < .0001) compared with male youths.

CONCLUSIONS

Increased exposure to recreational noise and minimal use of hearing protection might have lead to an increase in NITS prevalence among female youths.

Effects of the use of personal music players on amplitude modulation detection and frequency discrimination

Measures of auditory performance were compared for an experimental group who listened regularly to music via personal music players (PMP) and a control group who did not. Absolute thresholds were similar for the two groups for frequencies up to 2 kHz, but the experimental group had slightly but significantly higher thresholds at higher frequencies. Thresholds for the frequency discrimination of pure tones were measured for a sensation level (SL) of 20 dB and center frequencies of 0.25, 0.5, 1, 2, 3, 4, 5, 6, and 8 kHz. Thresholds were significantly higher (worse) for the experimental than for the control group for frequencies from 3 to 8 kHz, but not for lower frequencies. Thresholds for detecting sinusoidal amplitude modulation (AM) were measured for SLs of 10 and 20 dB, using four carrier frequencies 0.5, 3, 4, and 6 kHz, and three modulation frequencies 4, 16, and 50 Hz. Thresholds were significantly lower (better) for the experimental than for the control group for the 4- and 6-kHz carriers, but not for the other carriers. It is concluded that listening to music via PMP can have subtle effects on frequency discrimination and AM detection.