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   Abstract
   Introduction
   Materials and Me...
   Results
   Eardrum perforation
   Hearing loss
   Dizziness and ti...
   Discussion
   References
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Year : 2003  |  Volume : 5  |  Issue : 18  |  Page : 13-18
Inner ear damage in children due to noise exposure from toy cap pistols and firecrackers : A retrospective review of 53 cases

Department of Otolaryngology, Assaf Harofeh Medical Center, Affiliated to Sackler Faculty of Medicine, Tel Aviv University, Israel

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  Abstract 

This retrospective study presents the findings of inner ear damage documented in 53 children exposed to impulsive sound emitted by toy weapons and firecrackers. There were 49 boys and four girls aged between four and fourteen years. Thirty-nine children were affected unilaterally while fourteen had bilateral hearing loss (total of 67 ears). Most of the hearing loss (>70%) was sensorineural high frequency hearing loss, while only nine out of the 67 injured ears had sensorineural mid frequency hearing loss. Seven children sustained a traumatic ear drum perforation. Dizziness or tinnitus was reported by twenty children, with pathological ENG findings in four of them. This paper re-emphasizes the possibility of inner ear damage in children from exposure to noisy toys.

Keywords: Inner ear, children, noise, toys

How to cite this article:
Segal S, Eviatar E, Lapinsky J, Shlamkovitch N, Kessler A. Inner ear damage in children due to noise exposure from toy cap pistols and firecrackers : A retrospective review of 53 cases. Noise Health 2003;5:13-8

How to cite this URL:
Segal S, Eviatar E, Lapinsky J, Shlamkovitch N, Kessler A. Inner ear damage in children due to noise exposure from toy cap pistols and firecrackers : A retrospective review of 53 cases. Noise Health [serial online] 2003 [cited 2019 Oct 23];5:13-8. Available from: http://www.noiseandhealth.org/text.asp?2003/5/18/13/31823

  Introduction Top


Most of the papers on noise-induced hearing loss were reported on adults. Even the hearing protection regulations, which permit exposure to a sound level of 85 dBA for a maximum of eight hours per day, were designated for adults. These regulations also require that individuals (adults) should not be exposed to sound levels greater than 115 dBA (Hellstrom et al, 1992) or to peak levels of 140 dBA (Axelsson et al, 1991; Hellstrom et al, 1992). It has been shown that sound pressure levels produced by firecrackers reach peak levels of 145 to 160 dBA at the ear, when standing at a distance of 2 meters or less from the firecracker lying on a hard surface (Smoorenburg, 1978). These levels match those produced by firearms, up to 160 dBA for a pistol at the ear of the gunman (Smoorenburg et al, 1978). Therefore, there are strict regulations for ear protection for real gunmen. In spite of these common regulations for protection from shooting noise, no such hearing protection devices are required for children participating in activities with noisy toys, such as firecrackers and toy cap pistols.

The fact that a number of items used by children, or near them, have sound levels capable of producing temporary or permanent hearing loss, has been well known for the past three decades (Hellstrom et al, 1992). A previous investigation reported that teenage boys have a relatively higher incidence of high-frequency hearing loss than girls at the age of 13: 187/1198 (15.6%) in boys, and 101/1127 (9%) in girls (Axelsson et al, 1987). Such hearing loss has been attributed to excessive noise exposure from "noisy toys" (Axelsson and Jerson, 1985; Axelsson et al, 1981b; Lipscomb, 1972; Lipscomb, 1974; Roeser, 1980; Rytzner and Rytzner, 1981).

Despite awareness of the fact that noisy toys are capable of producing a hazardous noise level and the high incidence of teenage boys with high­tone hearing loss from exposure to "noisy games", no regulations for children concerning lowering noises from toys or use of noise protection devices, have been proposed.

The retrospective data of 53 children (67 ears), with proven inner ear damage from firecrackers or toy gun pistols, re-emphasizes the need for strict regulations regarding the permitted intensity of noise emitted from children's toys and firecrackers, and the use of hearing protection, especially during "New Year celebrations".


  Materials and Methods Top


A retrospective chart study was performed on 53 children between 1974 and 1997. All the children were exposed to excessive noise from noisy toys such as firecrackers, toy cap pistols, etc.

All the cases during the study period sought medical care due to exposure to noisy toys and met the following inclusion criteria: Exposure to excessive noise; First hearing test during the first three months after the exposure; Second hearing test between six to twelve months after the incident; No previous ear disease such as chronic otitis media.

All the children underwent a complete hearing test which included: pure tone audiometry (PTA) of bone conduction and air conduction thresholds, speech reception threshold (SRT) and discrimination. Those children complaining of dizziness or vertigo underwent Electronystagmography (ENG) during the first year post-exposure. Those who showed pathology on the ENG were re-examined.

There were 15 children who did not fulfil the above criteria. Two children with previous ear infection were excluded from the review because of the possibility of hearing loss due to the prior ear infection. The other 13 disappeared from follow up.


  Results Top


The following factors will be summarized: Eardrum perforation; audiometry results and hearing outcome; ENG results and tinnitus.


  Eardrum perforation Top


Seven children (17% of all 53 cases) suffered from traumatic eardrum perforations. All the injuries were the result of toy cap pistols or firecrackers that exploded near the injured ear. Five of them were less than 25% of the ty mpanic membrane and the other two were between 25 and 50% of the eardrum. All the perforations healed without treatment in less than one month. [Table - 1] summarizes the audiological findings and follow up.


  Hearing loss Top


There were 67 affected ears. Out of the 53 children, 39 children (74%) had unilateral sensorineural high tone hearing loss (SNHL), while 14 (26%) had bilateral hearing loss. Of these 14 children, eight had symmetrical hearing loss and six had asymmetrical audiological findings.

Most of the PTAs showed the classical high frequency SNHL with the notch between 4 to 6 kHz. Only 22% of the PTA showed sloping curve audiograms.

The severity of the acoustic trauma was divided into: mild when the hearing loss was up to 35 dBA in the 4-6 kHz range; moderate - between 35 and 45 dBA (PTA); and severe when the hearing loss was over 50 dBA. The same criteria were applied to the nine children with mid frequency SNHL.

Repeated hearing test after six to twelve weeks revealed an overall recovery rate of between 17% to 100%. (This does not include the seven children with mixed hearing loss.) [Table - 2] summarizes the audiometry results and the hearing outcome in the affected ears, according to the type of hearing loss. At six months follow up, 15% of those who improved had normal hearing, while 85% still had a slight hearing loss (high tone hearing loss in most cases).


  Dizziness and tinnitus Top


ENG including caloric test were performed for seven patients complaining of dizziness during the noise exposure. Three electronystagmo­graphic tests were normal, while four out of seven (57%) had pathological findings summarized in [Table - 3].

Thirteen children (25%) complained of tinnitus during the first audiological evaluation, while in eight out of the 13 cases (62%) (eight of 53 cases = 15%) the tinnitus persisted.

Two representative cases:

A toy gun pistol was shot near the left ear of a four-year-old child. He sustained pain and hearing loss immediately after the shot. Physical examination revealed a perforation in the anterior lower quadrant of the tympanic membrane. Hearing test showed a flat curve mixed hearing loss of both low and high frequencies, with a 15-20 dBA SRT. The perforation healed within three weeks after the incident. Hearing test that was performed eight months later revealed high tone hearing loss.

A 13-year-old child was playing with a firecracker. One of them exploded right next to his left ear. The boy fell down and complained of tinnitus, hearing loss and dizziness accompanied by vomiting. Physical examination revealed 1st degree burns of the auricle, tympanic membrane perforation and right-sided nystagmus. Hearing test performed three days after the incident revealed mixed hearing loss in the left ear, with 33 dBA SRT. Audiological evaluation of the right ear revealed slight high frequency SNHL. ENG performed four months after the explosion revealed signs of canal paresis on the left side along with direction fixed positional nystagmus to the right. Re­examination after one year revealed the same audiometry test results and the same result on the ENG.


  Discussion Top


High-frequency hearing loss has a relatively high incidence peak among the school age population (Hellstrom et al, 1992; Anderson, 1967; Anderson and Wedenberg, 1970; Lass et al, 1990). Such hearing loss is assumed to be caused by excessive noise exposure, mainly during recreational activities such as New Year celebrations (Anderson, 1967; Axelsson and Jerson, 1985; Axelsson et al, 1981a); Axelsson et al, 1981b; Lipscomb, 1972; Lipscomb, 1974; Plakke, 1985; Roeser, 1980; Rytzner and Rytzner, 1981). It was also shown that 15% of teenage boys have audiograms similar to those expected after exposure to high levels of noise (Axelsson et al, 1991; Axelsson and Jerson, 1985; Axelsson et al, 1987; Mills, 1975; Weber et al, 1967). Our study re-establishes the fact that boys are more frequently exposed to repeated noise. In our survey 39 of the children were boys (74%) and only four were girls. We believe that the reason is that boys engage in more noise aggressive behavior and more noisy games than girls. This is the same conclusion as Axelsson and Rytzner reported earlier (Axelsson et al, 1981a; Rytzner and Rytzner, 1981).

There is probably no otologist in the world who doubts that firecrackers or toy cap pistols can produce acoustic trauma (Ward and Glorig, 1961). Where unilateral high-frequency hearing loss (=4,000 Hz) is found incidentally in a boy or a young man, it is estimated that the reason is an accidental exposure to excessive noise; in children mostly due to toy cap guns or firecrackers, while in young men real explosions and gunfire (Ward and Glorig, 1961).

The damage from sound, on the sensitive organ of the inner ear, depends on the intensity and the duration of the sound. The duration of these impulses is very short - microseconds or a few milliseconds - and the apparent loudness of the sound decreases with duration of less than 25 microseconds (Axelsson et al, 1991). The sound pressure level produced by firecrackers exceeds 145 to 160 dBA peak level at the ear of an observer standing at a distance of 2 m from the explosion (Smoorenbrug, 1978). The same sound levels are produced by real firearms (Smoorenburg et al, 1978). This noise intensity can be potentially hazardous to the ear. Therefore, single hearing protection is recommended for outdoor shooting facilities and double hearing protection for indoor shooting (Smoorenburg, 1993). In spite of this, no regulation for firecrackers and toy cap pistols exists and recommendations for hearing protective devices are quite uncommon. No-one wears earmuffs or earplugs during firework displays at New Year's Eve.

Histological examination on guinea pigs exposed to sound pressure levels similar to those of firecrackers, showed pronounced outer hair cell loss (Axelsson et al, 1991; Robertson et al, 1979).

When dealing with this issue of inner ear damage in children due to exposure to intense sound levels from firecrackers and toy cap pistols, there are two major obstacles. The first is that the true incidence is unknown; the second is that we have no previous audiometry on those who are found to have hearing loss post-exposure. Addressing the second obstacle, none of the children in this series had an audiometry prior to the noise exposure. Nevertheless, we assume that all of them had normal hearing prior to the excessive noise exposure as none of them complained in the past. Another shortcoming of the study is the lack of information concenring hearing loss within the family. Ward and Glorig (1961) showed a case of a 21-year-old man with normal hearing prior to an explosion of a flashlight cracker about 15 inches from his right ear, and a subsequent right hearing loss as a result of acoustic trauma. Hearing loss recovery took one month. In another case report (McMillan and Kileny, 1994) of a 39-month-old child with normal hearing prior to an acoustic trauma from a bicycle horn, the child had a 50 dBA notch at 4 kHz six days after the exposure, but improved to 30 dBA after six weeks.

Our series showed an overall hearing recovery rate of 28%.

The exact incidence of SNHL in children due to exposure to noisy toys is unknown, mainly because the hearing loss is minimal with a high percentage of recovery and the children do not complain. However, it is assumed that the phenomenon is fairly common. Some of the children in our study sought medical help because of blast injury including tympanic membrane perforation and vertigo. Hearing studies in children before and after New Year or National Day celebrations, both of which are associated with the use of firecrackers, showed SNHL attributed to the noise exposure event (Axelsson, 1998). Weber et al. (1967) showed, in a review of hearing loss in 1,000 children, that 30% of them had SNHL related to exposure to gunfire, firecrackers and noisy recreational activities. Most of the SNHL in children has the characteristic of noise-induced hearing loss of adults, (high-tone hearing loss with dips at 4-6 kHz) (Axelsson, 1998).

Seventy eight percent of those suffering from hearing loss in our series showed a "notched" high-tone hearing loss, similar to noise-exposure audiometry. Although the issue of noise sensitivity in young humans is unknown (Axelsson, 1998), it is well documented that the child's external auditory canal (EAC) amplifies higher frequencies, for example 6 kHz, while lower frequencies, such as 2-3 kHz, are relatively more amplified in the adult EAC (Hellstrom, 1995). This means that the relatively high-pitched sounds from toys are more amplified in the EAC of children.

Despite the growing awareness of the hazardous sequela of hearing loss due to exposure to noisy toys in children, the incidence of SNHL in children has not decreased during the last two decades (Lass, 1990). About 10% of the population at risk (boys - 5-15 years old) has noise exposure hearing loss from firecrackers and other noisy games.

Our series reinforces the danger of noisy toys to the "sensitive" inner ear organs of children. The 53 children with hearing loss due to noise exposure from noisy toys were only the worst cases, but we believe that the problem is much more prevalent.

In order to reach safety levels for toys we are in agreement with Prasher and Patrick who, in a recently published article (Prasher and Patrick, 1998), stated and suggested the following: to lower the frequency of the sound emitted by toys; to lower the intensity of sound from toys; to determine age-specific safe levels of sound; to provide legislation for toy noise safety for manufacturers; to educate parents and children about the dangers of being exposed to high­intensity sound emitting toys.[33]

 
  References Top

1.Anderson U.M. (1967) The incidence and significance of high-frequency deafness in children. Am. J. Dis. Child. 113: 560-565  Back to cited text no. 1    
2.Anderson H., Wedenberg E. (1970) Genetic aspects of hearing impairments in children. Acta Otolaryngol. 69: 77­88  Back to cited text no. 2    
3.Axelsson A. (1998) The risk of sensorineural hearing loss from noisy toys and recreational activities in children and teenagers. Adv. Noise Res. 2: 78-90  Back to cited text no. 3    
4.Axelsson A., Aniansson G., Costa O.A. (1987) Hearing loss in school children. Scand. Audiol. 16: 137-143  Back to cited text no. 4    
5.Axelsson A., Hellstrom P.A., Altschuler R., Miller J.M. (1991) Inner ear damage from toy cap pistols and fire­crackers. Int. J. Pediatr. Otorhinolaryngol. 21: 143-148  Back to cited text no. 5    
6.Axelsson A., Hellstrom P.A., Miller J.M., Altschuler R.A. (1990) Inner ear damage from toy cap pistols and fire crackers. Paper presented at the meetings of the Association for Research in Otolaryngology, St. Petersburg, FL  Back to cited text no. 6    
7.Axelsson A. Jerson T. (1985) Noisy toys: a possible source of sensorineural hearing loss. Pediatrics. 79: 574-578  Back to cited text no. 7    
8.Axelsson A., Jerson T., Lindgren F. (1981a) Noisy leisure time activities in teenage children. Am. Ind. Hyg. Assoc. 42: 229-233  Back to cited text no. 8    
9.Axelsson A., Jerson T., Lindberg U., Lindgren F. (1981b) Early noise-induced hearing loss in teenage boys. Scand. Audiol. 10: 91-96  Back to cited text no. 9    
10.Barr B., Anderson H., Wedenberg E. (1973) Epidemiology of hearing loss in childhood. Audiology. 12: 426-437  Back to cited text no. 10    
11.Bock G.R., Saunders J.C. (1977) A critical period for acoustical trauma in the hamster and its relation to cochlear development. Science. 197: 396-398  Back to cited text no. 11    
12.Hellstrom P.A. (1995) Sound transfer function and hearing. Thesis. Gothenburg University  Back to cited text no. 12    
13.Hellstrom P.A., Axelsson A., Altschuler R., Miller J.M. (1991) Inner ear damage from toy cap pistols and fire­crackers. Int. J. of Pediatric Othorhinolaryngol. 21: 143­148  Back to cited text no. 13    
14.Hellstrom P.A., Dengerink H.A., Axelsson A. (1992) Noise levels from toys and recreational articles for children and teenagers. Br. J. Audiol. 26: 267-270  Back to cited text no. 14    
15.Henry K.R. (1982) Age-related changes in sensitivity of the post-pubertal ear to acoustic trauma. Hear Res. 8: 285­294  Back to cited text no. 15    
16.Kruger B. (1987) An update on the external ear resonance in infants and young children. Ear Hear. 8: 333-336  Back to cited text no. 16    
17.Kruger B., Ruben R.J. (1987) The acoustics properties of the infant ear. Acta Otolaryngol. (Stockh). 103: 578-585  Back to cited text no. 17    
18.Lass N.J., Woodford C.M., Lundeed C., English P.J., Schmitt J.F., Pannbacker M. (1990) Health educator's knowledge of hearing, hearing loss, and hearing health practices. Language, Speech and Hearing Services in Schools. 21: 85-90  Back to cited text no. 18    
19.Lipscomb D.M. (1972) The increase in prevalence of high frequency hearing impairment among college students. Audiology. 11: 231-237  Back to cited text no. 19    
20.Lipscomb D.M. (1974) Dangerous playthings. Noise: the unwanted sounds. Nelson-Hall, Chicago  Back to cited text no. 20    
21.McMillan P.M., Kileny P.R. (1994) Hearing loss from a bicycle horn. J. Am. Acad. Audiol. 5: 7-9  Back to cited text no. 21    
22.Mills J.H. (1975) Noise and children: a review of the literature. J. Acoust. Soc. Am. 58: 767-779  Back to cited text no. 22    
23.Plakke B.L. (1985) Hearing conservation in secondary industrial arts classes: a challenge for school audiologists. Language, Speech, and Hearing Services in the Schools. 16: 75-79  Back to cited text no. 23    
24.Prasher D., Patrick M. (1998) Noisy toys: a case for determining the hazard and safety levels. Adv. Noise Res. 2: 91-94  Back to cited text no. 24    
25.Robertson D., Cody A.R., Johnstone B.M. (1979) Inner ear damage caused by a toy cap pistol. J. Otolaryng. Soc. Austral. 80: 285-288  Back to cited text no. 25    
26.Roeser R.J. (1980) Industrial hearing conservation programs in the high schools (protect the ear before the 12 th year). Ear Hear. 1: 119-120  Back to cited text no. 26    
27.Rytzner B., Rytzner C. (1981) School children and noise. Scand. Audiol. 10: 213-216  Back to cited text no. 27    
28.Saunders J.C., Chen C.S. (1977) Sensitive periods of susceptibility to auditory trauma in mammals. Environ. Health Perspect. 44: 63-65  Back to cited text no. 28    
29.Smoorenburg G.F. (1978-11) Kans op gehoorgschade door vuurwerk. Report IZF (in Dutch). TNO Institute for Perception, Soesterberg  Back to cited text no. 29    
30.Smoorenburg G.F. (1993) Risk of noise-induced hearing loss following exposure to Chinese firecrackers. Audiology. 32: 333-343  Back to cited text no. 30    
31.Smoorenburg G.F., Mimpen A.M., Pols L.C.W. (1978-2) Geluiddrukniveaus rondom 18 vuurwapens en maxima voor het aantal schoten ter voorkoming van gehoorbeschadigingen. Report IZF (in Dutch). TNO Institute for Perception, Soesterberg  Back to cited text no. 31    
32.Ward W.D., Glorig A. (1961) A case of firecracker-induced hearing loss. Laryngoscope. 71: 1590-1596  Back to cited text no. 32    
33.Weber H.J., McGovern F.J., Zink D. (1967) An evaluation of 1000 children with hearing loss. J. Speech Hear. Dis. 32: 343-354  Back to cited text no. 33    

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Correspondence Address:
A Kessler
Department of Otolaryngology, Assaf Harofeh Medical Center, Affiliated to Sackler Faculty of Medicine, Tel Aviv University
Israel
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Source of Support: None, Conflict of Interest: None


PMID: 12631431

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    Tables

  [Table - 1], [Table - 2], [Table - 3]

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