Nonoccupational Noise Research Articles

Sound levels of the UVU pedestrian bridge

Utah Valley University provides a pedestrian bridge to travel from a train station to the school over Interstate-15. Due to traffic noise, people using the bridge could be exposed to sound levels that damage their hearing. Sound level measurements have been made at several locations on the bridge with two different instruments, the first being an Extech (Knoxville, USA) SL400 noise dosimeter and the other being a Larson Davis (Depew, USA) 831C sound level meter. Sound levels have ranged from 55 to 102 dB, depending on time of day and location on the bridge. In addition to our experimental results a COMSOL model was also developed to simulate the interactions of the freeway noise with the bridge, demonstrating how the geometry of the bridge affects the noise exposure of pedestrians. The Occupational Safety and Health Administration (OSHA) limit for non-occupational noise exposure of 100 dB is 15 minutes, suggesting that pedestrians that linger on the bridge could be exposed to damaging levels of sound. This research seeks to better understand and quantify the noise levels that pedestrians experience on the bridge.

Development of a clinical investigation protocol for occupational auditory health.

Considering that noise is present in different work environments, occupational health regulations have been created that advocate for the care of employees' auditory system in these environments. Occupational hearing assessment should be performed by audiologists through audiological examinations, otoscopy, as well as an interview to assess possible risk factors for the development of hearing loss. However, up to the present moment, a standardized set of updated questions for this interview has not been defined. To develop a clinical investigation instrument for occupational auditory health that provides support for clinical decision-making and differential diagnosis. The study was conducted using Design Thinking as a methodological approach in its stages of inspiration (problem identification), ideation (theoretical foundation and protocol design), and prototyping (protocol construction). This study was conducted with the objective of providing support for clinical decision-making and differential diagnosis of the auditory aspects of the assisted population. The Protocolo de Investigação Clínica da Saúde Auditiva Ocupacional was developed, consisting of six main sections that address medical history, lifestyle habits, exposure to non-occupational noise, work history, extra-auditory symptoms, and auditory and vestibular signs and symptoms, aimed at investigating workers' auditory health and related aspects. The developed instrument can be used for data collection and assist audiologists in the occupational health teams in diagnosis and decision-making processes.

The National Institute for Occupational Safety and Health recommended exposure level for noise needs to be revised downwards

Noise-induced hearing loss (NIHL) is caused by cumulative occupational and non-occupational noise exposure. The National Institute for Occupational Safety and Health (NIOSH) developed recommendations for occupational noise exposure in 1972, revised in 1998. Fifty years after the NIOSH 85 dBA recommended exposure level (REL) was first published, it needs to be revised downwards. In its calculations, NIOSH assumed that workers have quiet (<60 dBA) when not at work, something no longer true. Everyday public noise exposure now exceeds the Environmental Protection Agency's safe noise level, a time-weighted average of 70 dB for 24 hours, with multiple studies reporting average exposures near 75 dBA. Also, NIOSH calculations were based on occupational studies of material hearing loss measured by limited frequency pure tone audiometry, an insensitive measure of noise-induced auditory damage. Modern audiology techniques include extended range audiometry, speech in noise testing, diffusion product otoacoustic emissions testing, and questions about tinnitus and hyperacusis. Doing the needed research to support downward REL revision, detecting auditory damage in noise-exposed workers with these newer techniques, is a daunting task, but this is necessary both to protect workers and because the NIOSH REL forms the basis for the world's recommendations for non-occupational noise exposure.

What is the safe noise level to prevent noise-induced hearing loss?

Noise causes short-term mechanical and chemical changes in the cochlea, transduced into electrical signals transmitted to the brain. Excessive noise exposure overwhelms the cochlea’s ability to reverse these changes, causing noise-induced hearing loss (NIHL). The Centers for Disease Control and Prevention state that NIHL is the only completely preventable type of hearing loss. What is the evidence-based safe noise exposure level to prevent NIHL? The National Institute for Occupational Safety and Health (NIOSH) recommended exposure level (REL), 85 dBA, does not prevent NIHL. Occupational exposures are calculated for 8 hours/day, 240 days/year, for 40 years. To calculate the noise exposure level to prevent NIHL in the public, 70 dB for 24 hours (Leq(24) = 70), the Environmental Protection Agency (EPA) adjusted the REL for 24 hours/day, 365 days/year exposure. The actual safe noise exposure must be lower than 70 dB because 1) the EPA did not adjust for lifetime noise exposure, 2) NIOSH based its REL on limited-frequency pure tone audiometry, an insensitive measure of auditory damage, and 3) non-occupational noise exposure has increased. The safe noise level may be as low as 55 dBA, the effective quiet level required for humans to recover from noise-induced temporary threshold shift.

A Comparison of Self-Reported Nonoccupational Noise Exposure in a Large Cohort of Listeners.

A variety of questionnaires have been developed to describe and quantify occupational and nonoccupational noise exposure, which are associated with hearing loss and tinnitus. The main aim of this study was to compare and contrast three commonly used nonoccupational noise exposure measurement questionnaires in a group of young adults. A total of 197 participants were recruited for this study. All the participants completed three commonly used nonoccupational noise exposure measurement questionnaires via Qualtrics software (Qualtrics, Provo, UT). General patterns in the nature of noise exposure were highlighted and statistical agreement and correlations between the three instruments were calculated. Comparisons were made between self-percept of noise exposure and annual noise exposure metrics obtained using questionnaires. Strong statistical agreement and correlation (r = 0.57, P < 0.001) was found between the selected instruments similar in their constructs of noise exposure. When compared to quantified scores of noise exposure, self-report of exposure to loud noise was highly sensitive but associated with poor specificity (3.61%) and a high false-positive rate (96.38%). The majority of participants reported exposure to noise from listening to music and attending loud recreational activities, with a differential effect of sex on average annual noise exposure values depending on the questionnaire used. The outcomes of this analysis could assist in comparing noise exposure quantifications across research studies, and determining if and how these questionnaires may be utilized clinically to effectively identify and counsel those at risk for noise-induced hearing loss.

Personal Audio Systems Unsafe At Any Sound

Personal Audio Systems Unsafe At Any Sound

Too Loud: Noise Exposure in Everyday Life is Causing Hearing Loss

Too Loud: Noise Exposure in Everyday Life is Causing Hearing Loss

Investigating the effects of occupational and environmental noise on cardiovascular diseases: a systematic review and meta-analysis.

The present study aimed to use a meta-analysis to investigate the relationship between occupational and non-occupational noise exposure expressed in various studies with cardiovascular disease. This is a systematic review and meta-analysis study based on PRISMA checklist. In this study, the researchers searched five international databases of Medline/PubMed, Embase, Scopus, ISI/web of knowledge, and Google Scholar. Search keywords included two categories noise and noise pollution, cardiovascular disease, and hypertension. The Joanna Briggs Institute checklist was used to review and control the quality of the articles. After all screening stage 139 articles entered the final analysis. The results show that except for East African environmental studies and workplace studies in East Asia, Western Asia, and Northern Europe, there was a significant association between noise exposure and cardiovascular disease. Also, there was a significant difference between the intensity of sound and blood pressure in workers (OR = 1.28, CI 95%: 1.15-1.42, P < 0.001). Based on the results of environmental noise, there was a significant difference between ambient noise intensity and blood pressure (OR = 1.55, CI 95%: 1.53-1.57, P < 0.001). It can be concluded that it is very important to study and identify jobs or living environments with less than the recommended noise level and in addition to hearing aids that occur in over-standard exposures, such as cardiovascular disease.

Associations between indoor temperature and noise and semen parameters among participants in the US-based general population Growing Up Today Study

BACKGROUND AND AIM: Multiple environmental exposures have been suggested as important determinants of decreases in semen quality. However, very little is known regarding the impacts of non-occupational noise and indoor temperature exposures. Our aim was to explore these associations in a general population cohort of young men in the United States. METHODS: Participants were members of the prospective Growing Up Today Study. Exposures to noise, temperature, and relative humidity were collected every 5 minutes for 90 days in the main room of each home with a NetAtmo weather station. Semen samples collected at home were sent by express shipping to the Massachusetts General Hospital Andrology Laboratory; sperm concentration and morphology were assessed via computer-aided and manual methods. Associations per interquartile range (IQR) were assessed in three-exposure generalized linear models, adjusted for age, race, and body mass index. RESULTS:The first 82 participants were included in analyses (average age 35.6 years). The average sperm concentration was 56.5 (SD=36.9) M/ml and the percent normal morphology was 4.5% (SD=2.1). The average 90-day average noise level was 62.5 dB (SD=8.0), temperature was 22.0°C (SD=1.9) and relative humidity was 54.0% (SD=8.2). There was little evidence that the exposures were associated with sperm concentration (-1.91, 95%CI:-12.44, 8.63 per 9.83dB of noise; -3.73, 95%CI: -14.93, 7.46 per 2.53°C; 9.25, 95%CI: -0.78, 19.27 per 9.63% relative humidity) or % normal morphology (0.04, 95%CI: -0.58, 0.66 per 9.83dB of noise; -0.59, 95%CI: -1.23, 0.05 per 2.53°C; 0.04, 95%CI: -0.53, 0.61 per 9.63% relative humidity). CONCLUSIONS:In this cohort of general population US men, temperature, humidity, and noise in the 90 days before producing a semen sample were not associated with measures of semen quality. The impact of these exposures may be limited to sensitive time windows. KEYWORDS: Noise, Temperature, Relative Humidity, Reproductive Outcomes, Male, environmental epidemiology

Centers for Disease Control and Prevention non-occupational noise campaign

In February 2017, an intra-agency workgroup within the Centers for Disease Control and Prevention (CDC) National Center for Environmental Health (NCEH) launched a hearing loss campaign to increase awareness that excessive exposure to loud sounds outside of the working environment can lead to permanent noise-induced hearing loss (NIHL). The NCEH workgroup initiated research efforts and participated in activities to promote the prevention of NIHL from non-occupational noise exposures. This included the development of an online toolkit with infographics, videos, and other sharable media, several available in English and Spanish. Publication of CDC NIHL research has included peer-reviewed journals, partner articles and Morbidity and Mortality Weekly Report (MMWR) manuscripts. The CDC NIHL workgroup engages with various organizations and continues to analyze national data to prioritize public health needs in this area. CDC continues to develop communication materials, social media content, videos, and factsheets to support partners and other stakeholders. By providing evidence and education/health communication; through its partners CDC collaborates with other national efforts to increase awareness and behavioral change to prevent NIHL at home and in the community.

Improving our understanding on non-occupational noise-induced hearing loss

Noise is among the most common occupational and non-occupational exposures globally. As a result, the public health burden of noise-induced hearing loss is high. Some estimates suggest that roughly 20% of all hearing loss cases result from occupational noise exposure. Occupational noise exposures have been extensively studied and regulated in many countries for decades, and as a result the risk of occupational noise-induced hearing loss associated with different exposure levels and durations has been modeled and quantified. However, non-occupational exposures have not been nearly as well-characterized, and the risk of non-occupational noise-induced hearing loss is not well understood. This presentation will describe a systematic review conducted to evaluate the risk of noise-induced hearing loss associated with non-occupational noise. The presentation will also discuss knowledge gaps in our understanding of non-occupational noise exposures, and the need for tools to allow individuals to evaluate their own exposures against recommended non-occupational noise exposure limits, and ideally to share these “citizen-science” data for aggregated analysis. This approach is now being utilized in the Apple Hearing Study, a partnership between Apple, Inc., and the University of Michigan. Details will be provided on the research approaches and some preliminary results from the Apple Hearing Study.

Non-occupational noise exposure in the United States: A review

That occupational noise exposure causes hearing loss has long been known, but non-occupational noise exposure was generally not recognized as causing hearing loss until the 1960s. Audiometric evaluation of populations not exposed to occupational noise was used to establish normal hearing baselines for workers compensation purposes. Audiometery in these groups, and in isolated populations not exposed to loud noise, suggested that hearing was preserved without noise exposure. The word sociocusis was used to describe non-occupational hearing loss. There are no federal recommendations, guidelines, or standards for non-occupational noise exposure. Perhaps because of a misconception that the 85 A-weighted decibel recommended occupational noise exposure limit is safe for the public without time limit, everyday noise exposure appears to have increased. Noise-induced hearing loss (NIHL) has become a major public health problem in the U.S., with approximately 20% of adolescents age 12–19 and 25% of adults age 20–69 having NIHL Common sources of non-occupational noise exposure include transportation noise, music and entertainment including personal listening devices, restaurant noise, kitchen appliances and power tools, hobbies, and sports. Efforts to reduce non-occupational noise exposure must include public education and the promulgation and enforcement of standards for non-occupational noise exposure.

Effectiveness of a Novel Index System in Preventing Early Hearing Loss among Furniture Industry Skills Training Students in Malaysia.

Occupational noise-induced hearing loss (ONIHL) is the most reported occupational disease in Malaysia. ONIHL is aggravated by the presence of early hearing loss amongst the youth prior to entering a real working environment. At technical and vocational education training (TVET) institutions, students may develop early ONIHL because training workshops are designed imitating the industrial working environment to produce skilled workers. The exceeding noise level at workshops and recent risk of non-occupational noise can cause early ONIHL among these students. Therefore, ONIHL must be addressed at the early stage of producing skilled workers. Octa hearing conservation index (OHCI) system is developed as a management and monitoring tool for hearing conservation program (HCP) in TVET institutions. Six existing and two new HCP components were used to build the index system. A pilot test on the effectiveness of the OHCI system was conducted in a selected TVET institution for six months. The post-HCP shows a 52.6% improvement compared to the pre-HCP. The implementation of HCP has shown improved awareness on the hazards of loud noise exposure and active use of hearing protection devices among participants. The OHCI system has a great potential as a tool to improve HCP implementation in TVET institutions, and eventually, industry.

Larry H. Royster memorial session

Larry Royster conducted pioneering research on the effectiveness of occupational hearing conservation programs, with a particular focus on the performance of hearing protection devices (HPDs) and audiometric database evaluation. Dr. Royster also conducted important early research into non-occupational noise exposures such as sporting events, recreational activities, and air travel. This presentation will briefly review key findings from Dr. Royster's work on these topics from the 1970s–1990s, and will then summarize the findings of a number of recent related studies. These will include: an evaluation of hearing conservation program effectiveness and hearing protector performance among aluminum manufacturing workers; an assessment of the contributions of occupational and non-occupational noise to hearing loss risk in a large sample of individuals in New York City; and a review of patterns and trends in occupational noise exposures in the US from 1979–2013. Collectively, these studies indicate that the risk of hearing loss from noise remains substantial among US workers, as well as in the general public that participates in noisy leisure-time activities, and highlight the importance of continuing the research that Dr. Royster started in order to protect the hearing health of Americans.

Noise-induced hearing loss and its prevention: Integration of data from animal models and human clinical trials.

Animal models have been used to gain insight into the risk of noise-induced hearing loss (NIHL) and its potential prevention using investigational new drug agents. A number of compounds have yielded benefit in pre-clinical (animal) models. However, the acute traumatic injury models commonly used in pre-clinical testing are fundamentally different from the chronic and repeated exposures experienced by many human populations. Diverse populations that are potentially at risk and could be considered for enrollment in clinical studies include service members, workers exposed to occupational noise, musicians and other performing artists, and children and young adults exposed to non-occupational (including recreational) noise. Both animal models and clinical populations were discussed in this special issue, followed by discussion of individual variation in vulnerability to NIHL. In this final contribution, study design considerations for NIHL otoprotection in pre-clinical and clinical testing are integrated and broadly discussed with evidence-based guidance offered where possible, drawing on the contributions to this special issue as well as other existing literature. The overarching goals of this final paper are to (1) review and summarize key information across contributions and (2) synthesize information to facilitate successful translation of otoprotective drugs from animal models into human application.

Early hearing slope as a predictor of subsequent hearing trajectory in a noise-exposed occupational cohort.

Variations in individual susceptibility to noise-induced hearing loss have been observed among workers exposed to similar ambient noise levels but the reasons for this observation are poorly understood. Many workers are exposed to hazardous levels of occupational noise throughout their entire careers. Therefore, a mechanism to identify workers at risk for accelerated hearing loss early in their career may offer a time-sensitive window for targeted intervention. Using available longitudinal data for an occupationally noise-exposed cohort of manufacturing workers, this study aims to examine whether change in an individual's high frequency hearing level during the initial years of occupational noise exposure can predict subsequent high frequency hearing loss. General linear mixed modeling was used to model later hearing slope in the worse ear for the combined frequencies of 3, 4, and 6 kHz as a function of early hearing slope in the worse ear, age at baseline, sex, race/ethnicity, mean ambient workplace noise exposure, and self-reported non-occupational noise exposure. Those with accelerated early hearing loss were more likely to experience a greater rate of subsequent hearing loss, thus offering a potentially important opportunity for meaningful intervention among those at greatest risk of future hearing loss.

Association of organic solvents and occupational noise on hearing loss and tinnitus among adults in the U.S., 1999-2004.

Exposure to organic solvents and noise may be causal agents in the development of hearing loss and tinnitus. The objectives of the present study were to examine the association of organic solvents with hearing loss and tinnitus and to assess the interaction of organic solvent and occupational noise exposure on hearing loss and tinnitus. A secondary data analysis of data from the National Health and Nutrition Examination Survey and Occupational Information Network (O*NET) among a study population ranging from 1085 to 2471 study participants from 1999 to 2004. Multiple multivariate logistic regression models were used to assess the associations of individual organic solvent exposures as measured by blood biomarkers (1,4-dichlorobenzene, benzene, ethylbenzene, styrene, toluene, o-xylene, and m-/p-xylene) with self-reported hearing loss, audiometrically assessed hearing loss, and self-reported tinnitus. Models were adjusted for age, gender, race/ethnicity, diabetes, non-occupational noise exposure, smoking, and income. Organic solvents found to be statistically significantly associated with the outcome after adjusting for covariates were tested for interaction with occupational noise exposure. Solvent exposure was not statistically significantly associated with self-reported tinnitus. Benzene (OR 1.43, 95% CI 1.15-1.78), ethylbenzene (OR 1.24, 95% CI 1.02-1.50), and toluene (OR 1.27, 95% CI 1.06-1.52) concentrations were statistically significantly associated with increased adjusted odds of high-frequency hearing loss. No statistically significant interaction was observed between these solvents and occupational noise on high-frequency hearing loss. We found no evidence of an association between organic solvents and tinnitus; however, there was evidence of an association between organic solvent exposure and prevalence of high-frequency hearing loss.

Urban noise levels are high enough to damage auditory sensorineural health

ABSTRACT This commentary outlines the preventable auditory sensorineural health risk of cumulative episodic high-level indoor and outdoor non-occupational urban noise. Irreversible auditory sensorineural damage includes hidden hearing loss (cochlear synaptopathy), tinnitus, signal-to-noise ratio loss, noise-induced hearing impairment, and accelerated age-related hearing loss (presbycusis). There is evidence of ubiquitous high-level urban noise exceeding public health limits, and increased prevalence of sensorineural auditory damage in all age groups internationally. Sensorineural components differ greatly between late-onset sensory presbycusis in people with no hazardous exposure and early-onset neural presbycusis in people with a history of high noise exposure. Public health auditory safe listening limits are more stringent than occupational limits in order to fully protect the general population from permanent sensorineural noise damage. Speech interference noise limits prevent social isolation of individuals with noise-induced auditory system damage or hearing impairment from any cause. Quieter urban noise levels meeting public health limits are urgently needed to protect auditory sensorineural health, lower healthcare costs, and permit communication access in public spaces for people with auditory disabilities.

Construcción y Validación del Cuestionario de Percepción de Riesgos y Beneficios de la Exposición a Reproductores Personales de Música Para Adolescentes

Evidence has been found of an association between participation in risk behaviors and the perception of their risks and benefits. The use of personal music players (PMPs) is one of the most common non-occupational noise activities, especially among the young. The aim of the study was to develop a questionnaire to assess the positive consequences (benefits) perceived by adolescents and the negative consequences (risks) of listening to music on these devices. The construction and validation process occurred in 3 phases: item pool development; establishment of content validity; and estimation of construct validity, criterion-related validity, and internal consistency, with an accidental sample of 694 adolescents from 2 schools of Cordoba, Argentina. The results of the exploratory and confirmatory factor analyses revealed a 2-dimensional factorial structure. Together, both factors correctly classified 64.6% and 74% of adolescents with high and low exposure to music through PMPs. This questionnaire can be used to detect adolescents with risky listening and to develop strategies to promote protective behavior.

CDC Grand Rounds: Promoting Hearing Health Across the Lifespan.

Globally, one in three adults has some level of measurable hearing loss, and 1.1 billion young persons are at risk for hearing loss attributable to noise exposure. Although noisy occupations such as construction, mining, and manufacturing are primary causes of hearing loss in adults, nonoccupational noise also can damage hearing. Loud noises can cause permanent hearing loss through metabolic exhaustion or mechanical destruction of the sensory cells within the cochlea. Some of the sounds of daily life, including those made by lawn mowers, recreational vehicles, power tools, and music, might play a role in the decline in hearing health. Hearing loss as a disability largely depends on a person's communication needs and how hearing loss affects the ability to function in a job. The loss of critical middle and high frequencies can significantly impair communication in hearing-critical jobs (e.g., law enforcement and air traffic control).