Noise level analysis of commercially available toys

Preventing Excessive Noise Exposure in Infants, Children, and Adolescents

Noise exposure is a major cause of hearing loss in adults. Yet, noise affects people of all ages, and noise-induced hearing loss is also a problem for young people. Sensorineural hearing loss caused by noise and other toxic exposures is usually irreversible. Environmental noise, such as traffic noise, can affect learning, physiologic parameters, and quality of life. Children and adolescents have unique vulnerabilities to noise. Children may be exposed beginning in NICUs and well-baby nurseries, at home, at school, in their neighborhoods, and in recreational settings. Personal listening devices are increasingly used, even by small children. Infants and young children cannot remove themselves from noisy situations and must rely on adults to do so, children may not recognize hazardous noise exposures, and teenagers generally do not understand the consequences of high exposure to music from personal listening devices or attending concerts and dances. Environmental noise exposure has disproportionate effects on underserved communities. In this report and the accompanying policy statement, common sources of noise and effects on hearing at different life stages are reviewed. Noise-abatement interventions in various settings are discussed. Because noise exposure often starts in infancy and its effects result mainly from cumulative exposure to loud noise over long periods of time, more attention is needed to its presence in everyday activities starting early in life. Listening to music and attending dances, concerts, and celebratory and other events are sources of joy, pleasure, and relaxation for many people. These situations, however, often result in potentially harmful noise exposures. Pediatricians can potentially lessen exposures, including promotion of safer listening, by raising awareness in parents, children, and teenagers. Noise exposure is underrecognized as a serious public health issue in the United States, with exposure limits enforceable only in workplaces and not for the general public, including children and adolescents. Greater awareness of noise hazards is needed at a societal level.

An unusual case of sudden sensorineural hearing loss after cycling class

In this case report, our patient developed sudden sensorineural hearing loss (SSNHL) after loud noise exposure during a popular cardiovascular group exercise cycling class. To increase awareness among all healthcare professionals of the effects of these modern-day group fitness classes on hearing loss, we describe this case and review the current literature on SSNHL and its management. A 35-year old man developed SSNHL in the setting of loud noise exposure during a high intensity aerobic exercise class. After a short course of oral steroids with no improvement, intratympanic steroids were administered weekly for three weeks. The patient showed minimal improvement; thus, hyperbaric oxygen therapy was conducted. Serial audiograms continued to show severe to profound mixed hearing loss in the right ear. In conclusion, individuals who participate in loud, high-intensity aerobic group-exercise classes should be careful of the potential for noise-induced hearing loss. Aerobic exercise may make these individuals more susceptible to noise-induced hearing loss. Early intervention is critical for any chance of recovery.

Hazardous noise exposure from noisy toys may increase after purchase and removal from packaging: A call for advocacy

OBJECTIVE

Previous studies identified hazardous noise levels from packaged toys. Sound levels may increase when packaging is removed and therefore, complicate the ability to accurately assess noise levels before purchase. The goal of this study was to evaluate how packaging affects the decibel (dB) level of toys by: 1) Assessing dB level of toys with and without packaging. 2) Evaluating the percentage of packaged and unpackaged toys that exceed a safety limit of 85 dB.

METHODS

Thirty-five toys were selected from the 2009-2011 Sight and Hearing Association (SHA) based on availability for purchase. Toys' speakers were categorized as Exposed, Partially Exposed, or Covered, based on its packaging. The dB level of each toy was tested at 0 cm and 25 cm from the speaker using a handheld digital sound meter in a standard audiometric booth. T tests and ANOVA were performed to assess mean change in sound level before and after packaging removal.

RESULTS

Significant dB increases were noted after packaging was removed (mean change 11.9 dB at 0 cm; and 2.5 dB at 25 cm, p < 0.001). Sixty-four percentage of Covered toys (n = 14) had dB greater than 85 dB when packaged and this increased to 100% when unpackaged.

CONCLUSION

Many manufactured toys have hazardous sound levels. Caregivers and healthcare providers should be aware that toys tested in the store may actually be louder when brought home and removed from their packaging. Limits on and disclosure of dB level of toys should be considered nationally.

Loudness and acoustic parameters of popular children's toys

OBJECTIVE

This project was conducted to evaluate the loudness and acoustic parameters of toys designed for children. In addition, we investigated whether occluding the toys' speaker with tape would result in a significant loudness reduction; thereby potentially reducing the risk of noise induced hearing loss.

METHODS

Twenty-six toys were selected after an initial screening at two national retailers. Noise amplitudes at 0.25, 0.5, 1, 2, 4, and 8kHz were measured using a digital sound level meter at a distance of 0 and 30cm. The toys' speakers were then occluded using adhesive tape and the same acoustic parameters were re-measured.

RESULTS

Mean maximum noise amplitude of the toys at 0cm and 30cm was 104dBA (range, 97-125dBA) and 76dBA (range, 67-86dBA), respectively. Mean maximum noise amplitude after occlusion at 0cm and 30cm distances was 88dBA (range, 73-110dBA) and 66dBA (range, 55-82dBA), respectively, with a p-value <0.001.

CONCLUSIONS

Proper use of the loudest toys at a distant of 30cm between the speaker and the child's ear will likely not pose a risk of noise-induced hearing loss. However, since most toys are used at closer distances, use of adhesive tape is recommended as an effective modification to decrease the risk of hearing loss.

Noise producing toys and the efficacy of product standard criteria to protect health and education outcomes

An evaluation of 28 commercially available toys imported into New Zealand revealed that 21% of these toys do not meet the acoustic criteria in the ISO standard, ISO 8124-1:2009 Safety of Toys, adopted by Australia and New Zealand as AS/NZS ISO 8124.1:2010. While overall the 2010 standard provided a greater level of protection than the earlier 2002 standard, there was one high risk toy category where the 2002 standard provided greater protection. A secondary set of toys from the personal collections of children known to display atypical methods of play with toys, such as those with autism spectrum disorders (ASD), was part of the evaluation. Only one of these toys cleanly passed the 2010 standard, with the remainder failing or showing a marginal-pass. As there is no tolerance level stated in the standards to account for interpretation of data and experimental error, a value of +2 dB was used. The findings of the study indicate that the current standard is inadequate in providing protection against excessive noise exposure. Amendments to the criteria have been recommended that apply to the recently adopted 2013 standard. These include the integration of the new approaches published in the recently amended European standard (EN 71) on safety of toys.

Análise dos níveis de pressão sonora emitidos por brinquedos infantis

OBJETIVO: Verificar os níveis de pressão sonora emitidos por brinquedos infantis sem certificação. MÉTODOS: Estudo transversal com brinquedos sonoros ofertados em lojas de comércio popular, chamado de setor informal. Foram considerados brinquedos eletrônicos, mecânicos e musicais. A mensuração de cada produto foi realizada por um engenheiro acústico, em cabine isolada acusticamente, por meio de um decibelímetro. Para obter os parâmetros sonoros de intensidade e frequência, os brinquedos foram acionados a uma distância de 10 e 50cm da orelha do pesquisador. A intensidade foi verificada em nível de pressão sonora em decibéis dB(A) e a frequência, em hertz (Hz). RESULTADOS: Foram avaliados 48 brinquedos. Nas medidas a 10cm da orelha, foi registrada uma faixa de pressão sonora de 102±10 dB(A) e, a 50cm, a média foi de 94±8 dB(A), com p<0,05. A maioria dos brinquedos apresentou nível de pressão sonora acima de 85dB(A). A frequência variou de 413 a 6.635Hz, sendo que 56,3% dos brinquedos emitiram som com frequência superior a 2.000Hz. CONCLUSÕES: Constatou-se que a maioria dos brinquedos emitiu sons com elevado nível de pressão.

Systematic Assessment of Noise Amplitude Generated by Toys Intended for Young Children

Objective

To systematically evaluate the noise generated by toys targeted for children and to compare the results over the course of 4 consecutive holiday shopping seasons.

Study Design

Experimental study.

Setting

Academic medical center.

Subjects and Methods

During 2008-2011, more than 200 toys marketed for children older than 6 months were screened for loudness. The toys with sound output of more than 80 dBA at speaker level were retested in a soundproof audiometry booth. The generated sound amplitude of each toy was measured at speaker level and at 30 cm away from the speaker.

Results

Ninety different toys were analyzed. The mean (SD) noise amplitude was 100 (8) dBA (range, 80-121 dBA) at the speaker level and 80 (11) dBA (range, 60-109 dBA) at 30 cm away from the speaker. Eighty-eight (98%) had more than an 85-dBA noise amplitude at speaker level, whereas 19 (26%) had more than an 85-dBA noise amplitude at a 30-cm distance. Only the mean noise amplitude at 30 cm significantly declined during the studied period ( P < .001). There was no significant difference in mean noise amplitude of different toys specified for different age groups.

Conclusion

Our findings demonstrate the persistence of extremely loud toys marketed for very young children. Acoustic trauma from toys remains a potential risk factor for noise-induced hearing loss in this age group, warranting promotion of public awareness and regulatory considerations for manufacture and marketing of toys.

Análise acústica em brinquedos ruidosos

OBJETIVO: analisar os níveis de ruídos emitidos por brinquedos nacionalmente comercializados, utilizados por crianças de 1 a 5 anos; comparar os valores entre os brinquedos com e sem selo do Inmetro (Instituto Nacional de Metrologia, Normalização e Qualidade Industrial) e analisar o espectro acústico dos brinquedos, com o intuito de identificar a área da cóclea que pode ser mais afetada por esses ruídos. MÉTODO: as medições foram realizadas em 20 brinquedos sonoros (10 com o selo do Inmetro e 10 sem o selo) com o uso do decibelímetro digital em sala acusticamente tratada, e a análise dos sons emitidos pelos brinquedos foi realizada por meio do programa Praat. RESULTADOS: a intensidade do ruído dos brinquedos com o selo do Inmetro posicionados a 2,5 cm do equipamento variou de 61,50 a 91,55 dB(A) e 69,75 a 95,05 dB(C) e a referente à distância de 25 cm variou entre 58,30 a 79,85 dB(A) e 62,50 a 83,65 dB(C). A intensidade do ruído dos brinquedos sem o selo do Inmetro a 2,5 cm variou entre 67,45 a 94,30 dB(A) e 65,4 a 99,50 dB(C) e na distância de 25 cm registrou desde 61,30 a 87,45 dB(A) e 63,75 a 97,60 dB(C), portanto os achados demonstraram que existem brinquedos ruidosos que ultrapassam os valores recomendados pela legislação vigente em ambos os grupos, com e sem selo do Inmetro. CONCLUSÃO: os brinquedos sem o selo do Inmetro apresentaram valores de intensidade significantemente maior em relação ao outro grupo, oferecendo maior risco à saúde auditiva das crianças.

Causation of permanent unilateral and mild bilateral hearing loss in children

Children with permanent unilateral or mild bilateral hearing loss have been a focus of concern by audiologists, educators, and physicians for at least 2 decades. These children are known to be at risk for psychoeducational difficulties. However, despite this concern, little has been learned about the causative factors of these hearing losses and how those factors might be contributing to child development. This review of known causes of permanent unilateral and mild bilateral hearing loss in children is meant to draw attention to the importance of the search for etiologic factors. That is, the identification of the hearing loss should not signal the end of the diagnostic process but, rather, the beginning of a search for causation. With the combined efforts of audiologists, otolaryngologists, pediatricians, geneticists, and other medical professionals, we may enhance our understanding of the primary causes of unilateral and mild bilateral hearing loss and, perhaps, create links between causative factors and psychosocial and psychoeducational outcomes.

Influence of leisure-time noise on outer hair cell activity in medical students

OBJECTIVE

Noise exceeding a certain level can damage outer hair cells and thus cause hearing loss. In the past, noise-induced hearing loss was mainly caused by occupational noise. Leisure-time noise may be a promoting factor, particularly in young adults. The purpose of this study was to investigate whether transient evoked otoacoustic emissions (TEOAE) can be used to evaluate outer hair cell damage in young adults with no history of hearing complaints. The data obtained from the measurement of TEOAE were correlated with the participants' listening habits and exposure to leisure-time noise.

METHODS

Eighty-eight young adults (47 women, 41 men; age 22.9+/-2.9 years) were examined. TEOAE were measured using standard ILO 88 equipment. All participants had normal hearing (hearing thresholds better than 20 dB HL; frequency range 0.125-10 kHz). None of the participants suffered from permanent tinnitus. All participants answered a questionnaire concerning their listening habits.

RESULTS

On average, the participants frequented a discotheque 1.4 times a month; 25% had never visited a discotheque, 35% visited once a month and 32% twice or three times a month. Sixteen per cent reported transient tinnitus after every visit to a discotheque and 58% after nearly every visit. Eight per cent suffered from transient hearing loss after every visit to a disco and 37% after nearly every visit. Three per cent (4%) reported tinnitus (nearly) every morning after visiting a discotheque. The TEOAE level was above 6 dB in all participants [9.2+/-3.6 dB (mean +/- SD)] and reproducibility was above 60% (90+/-9%). All values matched pass criteria for normal TEOAE under clinical conditions. However, TEOAE levels and reproducibility decreased significantly with an increased number of visits to discotheques.

CONCLUSION

Outer hair cell damage could be measured using TEOAE in individuals exposed to leisure-time noise, although these individuals exhibited no measurable puretone hearing loss.

Estimated prevalence of noise-induced hearing threshold shifts among children 6 to 19 years of age: the Third National Health and Nutrition Examination Survey, 1988-1994, United States

OBJECTIVE

This analysis estimates the first nationally representative prevalence of noise-induced hearing threshold shifts (NITS) among US children. Historically, NITS has not been considered a common cause of childhood hearing problems. Among children, NITS can be a progressive problem with continued exposure to excessive noise, which can lead to high-frequency sound discrimination difficulties (eg, speech consonants and whistles).

METHODS

The Third National Health and Nutrition Examination Survey (NHANES III) was conducted from 1988 to 1994. NHANES III is a national population-based cross-sectional survey with a household interview, audiometric testing at 0.5 to 8 kHz, and compliance testing. A total of 5249 children aged 6 to 19 years completed audiometry and compliance testing for both ears in NHANES III. The criteria used to assess NITS included audiometry indicating a noise notch in at least 1 ear.

RESULTS

Of US children 6 to 19 years old, 12.5% (approximately 5.2 million) are estimated to have NITS in 1 or both ears. In the majority of the children meeting NITS criteria, only 1 ear and only 1 frequency are affected. In this analysis, all children identified with NITS passed compliance testing, which essentially rules out middle ear disorders such as conductive hearing loss. The prevalence estimate of NITS differed by sociodemographics, including age and sex.

CONCLUSIONS

These findings suggest that children are being exposed to excessive amounts of hazardous levels of noise, and children's hearing is vulnerable to these exposures. These data support the need for research on appropriate hearing conservation methods and for NITS screening programs among school-aged children. Public health interventions such as education, training, audiometric testing, exposure assessment, hearing protection, and noise control when feasible are all components of occupational hearing conservation that could be adapted to children's needs with children-specific research.

Selected topics related to occupational exposures

The auditory and nonauditory effects of noise can be quite profound, affecting approximately 15 to 20 million Americans. As with most occupational toxins, recognition and careful assessment of noise exposure are the foundation on which preventive measures and treatment are based. Dosimeters can measure noise exposure over specific time periods. Pure tone air conduction audiometric monitoring should be performed on an annual basis in workers at risk for significant noise exposure. Occupational infectious disease involves far more than hepatitis and tuberculosis. Periodic fever, dermatologic manifestations and other symptoms peculiar to a specific disease may be important clues to an occupationally related exposure. Whereas strict attention to hand washing and isolation are cornerstones of prevention, use of protective gear is mandated in certain situations. Zoonotic disease, agriculture exposure, water transmission, and biologic contaminants in buildings can be important but subtle exposures sources. Recognition of these infections often depends on the alertness of the primary care giver.