Background: Many public health professionals have expressed concern that regular participation in recreational settings with high noise levels might induce hearing loss. This study measures the noise levels in a baseball stadium and analyzes baseball fans’ attitude of effect of recreational noise exposure on their hearing. Methods: In the baseball stadium, noise levels from the beginning to the end of four games were measured in four seating sections, the red, blue, navy, and outfield sections using a sound level meter. For the survey sample, 344 randomly selected participants who visited the stadium and/or were baseball fans completed a 16-question survey on their noise exposure during the game and on the potential risk of hearing loss. Results: The LAeq average of the 16 measures produced 91.7 dBA, showing a significantly high noise level in the red and navy sections. As a function of frequency by LZeq analysis, the noise levels of low frequencies between 0.05 and 1 kHz were significantly higher than other frequencies except for the outfield section, but the levels abruptly decreased above 1 kHz. Despite the very high noise levels, 70% of the respondents preferred sitting in either the red or the navy section to be closer to the cheerleaders and to obtain a good view. Most respondents reported that they did not consider wearing earplugs, and one-third experienced hearing muffled speech after the game. Notably, they agreed that an information announcement regarding loud noise and hearing protection was needed at the stadium. Conclusions: We conclude that the noise levels in baseball stadiums are high enough to cause hearing damage and/or tinnitus later when applying a rule of 85 dB LAeq for 8 hours with a 3-dB exchange rate. We expect these results to improve public education regarding safe noise exposure during popular sports activities.

Objective: The present study compared recognition of native and non-native consonants in quiet and noise among native speakers of Malayalam. Methods and Material: Fifteen native speakers of Malayalam who had English as the medium of instruction at school participated in the study. Stimuli comprised of 16 vowel-consonants-vowel nonsense syllables spoken by eight native speakers of Malayalam (native consonants) and eight native speakers of American English (non-native consonants). Recognition of native and non-native consonants was studied in quiet and in the presence of speech-shaped noise at signal-to-noise ratios (SNRs) of 8 dB, 0 dB, and −8 dB. The consonant recognition task was carried out as 16-alternative forced-choice procedure, and the responses were stored as confusion matrix. Results: In favourable listening condition (i.e., quiet and 8 dB SNR), the recognition score for native consonants was greater than non-native consonants. In contrast, at 0 dB SNR and −8 dB SNR, the recognition score of non-native consonants was greater than native consonants. Information transfer analysis revealed that the transfer of information was highest for consonant feature manner of articulation and lowest for voicing, across listening conditions for both native and non-native consonants. Conclusions: Recognition of native and non-native consonants were affected differently in the presence of speech-shaped noise among native speakers of Malayalam. In favourable listening condition, recognition of native consonants was better than non-native consonants. However, in challenging listening condition, non-native consonants were found to be recognised better than native consonants.

Context: Noise-induced hearing loss (NIHL) is considered as a common occupational hazard among the industrial workers. The printing press is one of the common industrial set up where noise levels are often high. The awareness of people working in such a setup is generally less towards the hazards that is caused by noise exposure. Aim: The current study was designed to identify the knowledge, attitude, and practice (KAP) of printing press workers towards NIHL. Settings and Design: Cross-sectional study was carried using an adapted and validated KAP questionnaire. It was administered on 57 workers in Thiruvananthapuram, Kerala. Methods and Material: The study was carried out in two phases: phase I included the adaptation and validation of KAP questionnaire to printing press workers. Phase II comprised of the administration of the questionnaire among the study population. Statistical analysis used: Descriptive statistics was used to compile the results. To measure the internal consistency Cronbach’s alpha scale was used. Results: The responses obtained from workers showed inadequate knowledge, negative attitudes in certain subdomains and poor practice. Conclusions: The findings from the present study sheds light on the dearth of awareness in printing press workers on hearing conservation and need of training programs to educate the printing press workers towards the effects of NIHL.

Objective: The aim is to investigate whether noise is effective on hearing screening tests of neonates born to mothers exposed to noise during pregnancy. Material and Method: Screening results of 2653 infants from the period of January 2013–May 2017 were evaluated. Transient Evoked Otoacoustic Emissions (TEOAE) and Auditory Brainstem Response (ABR) were used. Infants of 65 mothers exposed to noise (L_Aeq 80–85 dBA/8 hours/day) during pregnancy (Week ± SD; 32.58 ± 2.71) comprised the study group while the control group consisted of infants of 2588 mothers without noise exposure. Results: Among the 65 infants, 23 (35.4%) passed screening at the first emission test (OAE1); 34 (52.3%) at the second emission test (OAE2); 7 (10.8%) at the ABR stage, 1 (1.5%) infant was referred to a tertiary center. In the control group, 458 (17.7%) infants passed at OAE1; 1822 (70.4%) at OAE2; 289 (11.2%) at ABR stages, 19 (0.7%) infants were referred to a tertiary center. The rate of infants that passed screening at OAE1 in the study group was high (P = 0.00001). Sixty-four (98.46%) infants in the study group and 2569 (99.26%) infants in the control group passed the tests. The difference between the two groups was not significant, indicating that exposure to noise during pregnancy had no unfavorable effects on auditory functions (P = 0.392). Conclusion: Unfavorable effect of noise exposure during pregnancy was not observed on auditory functions of the infants. The higher rate of infants that passed the screening test at OAE1 stage in the study group raised the question, “Does the exposure of the noise at exposure action levels (80–85 dB A) during pregnancy contribute to auditory maturation of fetus?”

Aim: To investigate the association between the single nucleotide polymorphism in the position-889 (C/T) of the promoter region of the IL-1α gene and the susceptibility to tinnitus. Method: This was a case-control study with a sample of 108 independent elderly people over 60 years of age. Information on exposure to occupational noise and tinnitus was obtained by interviews. The genetic polymorphism was analyzed by polymerase chain reaction followed by cleavage with restriction enzyme NcoI. Data were analyzed using the Chi-square test, with the significance level set at 5%. For the statistical analysis all individuals with tinnitus on the right ear were eligible. Results: Among elderly with tinnitus, 42.9% had a history of exposure to occupational noise. There was statistically significant association between IL-1α gene polymorphism and tinnitus in subjects without a history of exposure to occupational noise (P  = 0.006 and χ² = 10.39). The elderly with the T allele were less likely to have tinnitus due to occupational noise exposure when compared to those carrying the C allele. Conclusion: This study suggests an association between the IL-1α gene polymorphism with susceptibility to tinnitus in individuals without a history of exposure to occupational noise. The present study demonstrated that allele T of IL-1α is a protective factor for presence and severity of tinnitus in the elderly and allele C contributes to the pathogenesis of the inflammatory response. The present observation implied the signaling IL-1α is involved in ear aging.

Introduction: An optimal classroom acoustic environment is essential for children with hearing impairment to achieve academic success. The aim of the present study is to provide an overview of classroom listening conditions in schools for children with hearing impairment in a developing country context. Materials and Methods: Noise levels were measured in 37 classrooms from four schools in Chennai, India. Teacher speech levels were measured to obtain classroom speech to noise ratio (SNR) data. The reverberation time was estimated for each classroom. Results: The mean noise level and reverberation time in all classrooms exceeded recommended maximum levels. The measured SNRs were not optimal for children with hearing impairment. Observations of the classrooms revealed that acoustical treatments were inadequate. Conclusion: The results indicated that Indian schools for children with hearing impairment should take steps to improve classroom listening environments. Possible solutions that may alleviate suboptimal classroom sound environments are discussed.