Investigation of Noise Induced Hearing Loss Among Power Loom Industry Workers in Tamil Nadu, India

Abstract

Noise-induced hearing loss remains a prevalent occupational concern across various industries. This study aimed to address several key objectives regarding noise exposure and hearing impairment among power loom workers in Tamil Nadu, India. The major objectives were to assess the levels of noise exposure in the power loom industry and to determine the prevalence of hearing loss among the workers. The minor objectives included identifying the specific factors associated with hearing loss and proposing measures to mitigate noise exposure. A cross-sectional study was carried out at a Power Loom Industry in the Erode District of Tamil Nadu between September and November 2023. A total of 123 workers from weaving sections were randomly selected to participate in face-to-face interviews using a structured questionnaire. Noise exposure levels were measured using a noise meter, while hearing loss was assessed using a pure tone audiometer. Logistic regression analysis was conducted to identify factors associated with hearing loss. Among the workers, 88.5% were exposed to noise levels of ≥ 95 dB (A), and the prevalence of hearing loss was 71.6%. Factors positively associated with hearing loss included age between 31–50 years and over 50 years, lack of literacy, experiencing hearing difficulties or earaches, hypertension, and more than 15 years of service in the power loom industry. To mitigate noise exposure levels, there is a need for enhanced occupational hazard education and stricter enforcement of safety regulations. Regular audiometry tests should be implemented to monitor hearing threshold shifts. Employers should establish and enforce hearing conservation programs in workplaces where noise exposure exceeds or reaches 95 dB (A).

Introduction

On a global scale, hearing loss ranks as the fourth highest cause of disability, affecting an estimated 480 million individuals. Particularly in developing countries, occupational noise exposure stands as the second most self-reported occupational illness, profoundly impacting industrial workers on functional, social, emotional, and economic levels [1]. Noise-induced hearing loss (NIHL) poses a significant occupational hazard, especially prevalent among textile workers [2]. This condition arises from prolonged exposure to sound levels or durations that damage the delicate hair cells within the cochlea. NIHL often progresses gradually over time due to continuous exposure to excessive noise generated by manufacturing industries. The consequences of NIHL extend beyond mere auditory impairment [3]. Workers afflicted by this condition often experience diminished quality of life due to communication difficulties, social isolation, and psychological strain. Additionally, the economic ramifications are substantial, as affected individuals may face reduced employment opportunities and increased healthcare costs [4].

Noise refers to any unwanted disturbance within a useful frequency band, encompassing undesired electric waves in a transmission channel or device. It is typically categorized as environmental noise and occupational noise, depending on its impact on human well-being [5]. Occupational noise, considered one of the most insidious of all industrial pollutants, pervades across various industries. Exposure to excessive levels of occupational noise can lead to hearing loss, characterized by partial or complete impairment in one or both ears due to employment-related factors [6]. Globally, a significant portion of disabling hearing loss in adults, approximately 16%, is attributed to occupational noise exposure. This statistic underscores the profound impact that workplace noise can have on auditory health and highlights the importance of implementing effective noise control measures in industrial settings [7].

Exposure to sudden impulse noise poses a greater risk than exposure to steady-state noise, often resulting in what is termed acoustic trauma. Acoustic trauma, whether from a single intense exposure or repeated occurrences, can lead to significant damage to the inner ear. Noise trauma can manifest in two primary forms of injury to the inner ear: temporary threshold shift (TTS) and permanent threshold shift. TTS is typically reversible and may occur due to the temporary uncoupling of outer hair cell stereocilia from the tectorial membrane [8, 9]. Conversely, permanent threshold shift, a hallmark of noise-induced hearing loss (NIHL), is characterized by irreversible damage. In cases of permanent threshold shift, a distinct pathological feature is the pronounced loss of outer hair cells, particularly evident in the basal turn of the cochlea [10]. The severity of damage to the inner ear correlates with the intensity and duration of noise exposure. Prolonged or intense noise levels have the potential to disrupt not only individual hair cells but also the entire organ of Corti, the essential structure responsible for detecting sound vibrations. Understanding these mechanisms is crucial for implementing effective prevention strategies and interventions to safeguard against the debilitating effects of noise-induced hearing loss [11].

The human ear exhibits varying sensitivity to sounds across different frequencies. To account for this, a spectral sensitivity factor known as the A-weighting filter is applied to weight the sound pressure level at different frequencies, resulting in A-weighted sound pressure levels expressed in units of decibels (dB (A)) [12]. In occupational settings, the National Institute for Occupational Safety and Health (NIOSH) recommends a recommended exposure limit for occupational noise exposure, set at 85 dB(A) as an 8-h time-weighted average (8-h TWA). Exposures exceeding this level are deemed hazardous, as prolonged exposure to noise levels at and above 95 dB (A) can lead to significant hearing damage and contribute to noise-induced hearing loss (NIHL) [13, 14].

In developing countries, the impact of occupational noise exposure tends to be more pronounced in men than in women. Continuous or intermittent exposure to occupational noise can lead to accelerated rates of hearing loss, particularly within the first 10 to 15 years of exposure [15]. Factors such as the level of noise exposure, age, smoking habits, elevated blood pressure, and duration of employment are closely associated with the development of hearing impairment among workers [16]. Furthermore, occupational noise exposure can contribute to psychological stress and adversely affect job performance [17, 18]. Workers may experience increased levels of stress and difficulties in concentration due to the disruptive nature of excessive noise in the workplace [19]. To assess hearing sensitivity and detect hearing loss among individuals exposed to occupational noise, pure-tone testing is commonly employed. This involves the use of a pure-tone audiometer to measure an individual’s hearing threshold levels across various frequencies [20]. The results are then plotted on an audiogram, providing a detailed description of auditory sensitivity. Based on the audiogram, hearing ability is categorized into different levels: normal hearing (0–25 dB) and varying degrees of hearing loss (> 25 dB). This diagnostic tool is invaluable for monitoring the hearing health of workers and implementing appropriate interventions to prevent further hearing deterioration [21].

Despite the preventable nature of hearing loss, many Asian developing countries face significant challenges in providing accessible healthcare services and prevention programs. In these regions, limited awareness about noise-induced hearing loss (NIHL) among both employers and employees presents a major barrier to effective prevention efforts [22]. Furthermore, the development and implementation of comprehensive hearing conservation programs are hindered by various weaknesses, including inadequate measures for noise level reduction, gaps in regulatory frameworks, and suboptimal utilization of personal protective devices (PPDs) in occupational settings [23]. In India, specifically, there is a notable absence of a coordinated national program for the prevention of deafness and hearing loss. While the Committee on Prevention and Control of Deafness takes steps to safeguard hearing health in the industrial sector, there remains a critical need for more robust initiatives. The main objectives of this study were to explore the level of noise exposure and to assess factors associated with hearing loss among Power Loom Workers in Tamil Nadu, India. By examining these factors, the study aimed to inform targeted interventions and policies to protect the hearing health of industrial workers in the region.

Methodology

Study Design, Area, and Period

A cross-sectional descriptive study was undertaken among workers employed in the power loom industry located in the Erode district of Tamil Nadu, India, spanning from September to November 2023. This study focused specifically on 123 workers assigned to weaving sections within the textile power loom mill. These workers were subjected to prolonged exposure to excessive levels of noise, with measurements reaching up to 95 dB within the workplace environment.

Sample Size and Sampling Techniques

The sample size was determined using a single population proportion formula, incorporating a hearing loss proportion of 0.26 obtained from a prior study conducted in Turkey [24]. A margin of error of 0.06 and a Z score corresponding to a 95% confidence interval (CI) of 1.96 were employed in the calculation. Additionally, a 10% allowance for non-response was factored in, resulting in a final sample size of 123 participants. Exclusion criteria were applied to ensure the integrity and reliability of the study findings. Workers who did not provide informed consent, individuals with hereditary hearing loss, those with a history of head injury or ear infections, individuals exposed to ototoxic drugs or chemicals, and those exposed to occupational noise less than 12 h prior to audiometric assessment were excluded from participation.

Data Collection Methods

Data collection involved a combination of interviews, noise level measurements, and assessments of hearing loss. Participants engaged in face-to-face interviews conducted by trained interviewers using structured questionnaires. The questionnaire comprised three sections: demographic details including gender, age, educational attainment, and current work section; inquiries about health issues such as hearing difficulties, headaches, earaches, and hypertension; and factors related to noise exposure, including tenure at the textile mill, duration of service in the current work section, daily duration of occupational noise exposure, utilization of personal protective devices (PPDs), and noise exposure levels.

Noise exposure levels in each section were measured using the Oizom Polludrone device [17, 18], positioned at least 1 m away from the noise source. The device conducted 15 hourly measurements during working hours over an 8-h period to account for fluctuations in the production process, recording the 8-h Time-Weighted Average (TWA). Hearing loss assessments were conducted using a PC-based Pure-Tone Audiometer (PTA), administered by trained technicians from the Occupational and Environmental Division to minimize bias. Only one participant and technician were present in the examination room during each test, with ambient noise levels recorded to ensure they remained below 35 dB. All audiometric tests were conducted prior to workers entering their respective sections to mitigate the effects of Temporary Threshold Shifts (TTS). Audiograms were reviewed by an otolaryngologist to identify hearing loss, with confirmation provided by an occupational physician.

Operational Definitions

Listening to loud music involves using earbuds connected to devices like media players, resulting in exposure to high sound levels. The duration of service in a textile mill refers to the total number of years worked in the mill. If the duration includes a decimal greater than 6 months, it is rounded up to 1 year; otherwise, it is considered as 0 years. Similarly, the duration of service in the current section of the mill is calculated based on the total number of years worked in that specific weaving section. Noise exposure level, typically averaged over an 8-h workday, is categorized as high if it exceeds 95 dB (A) and low if it falls below that threshold. Personal protective device (PPD) utilization involves wearing earplugs or earmuffs to shield against workplace noise exposure. Hearing thresholds in frequencies ranging from 0.25 to 8 kHz were determined for both ears of all workers using a pure-tone audiometer. The measurement of hearing thresholds was conducted in 5 dB increments. Workers were considered to have hearing loss if the average hearing thresholds across frequencies of 4, 6, and 8 kHz exceeded 25 dB in each ear [25, 26].

Data Analysis

The collected data underwent thorough checks for completeness, accuracy, and relevance. Following validation, the data were entered into Excel 2021 and subsequently cleaned before being exported to the Statistical Package for Social Sciences (SPSS) program, version 23, for analysis. Summarization of the data was achieved through the utilization of tables, charts, and graphs. Descriptive statistics were presented in the form of frequency (percentages) for categorical variables and mean values with standard deviation (SD) for continuous variables. Bivariate logistic regression analysis was conducted on each independent variable, with respective odds ratios (OR) calculated. To address potential confounding factors, multivariate analysis was performed using a forward conditional logistic regression model. This model included only those variables that demonstrated significance in the bivariate analysis, allowing for the detection of factors associated with hearing loss. The significance of the association between independent and dependent variables was assessed using a 95% confidence interval (CI) and respective odds ratios (OR). A two-tailed p-value less than 0.05 was considered indicative of statistical significance.

Results

Socio-Demographic Characteristics of Workers

A total of 123 individuals employed in power loom weaving sections were included in the study. As indicated in Table 1, the majority of participants were male, comprising 70.73% of the study population, whereas females constituted only 29.2%. The average age of the workers was 37.23 years (standard deviation: 10.72), ranging from 20 to 60 years, with over half (55.1%) falling below the age of 30. In terms of educational attainment, the distribution was as follows: 44.7% were classified as illiterate, 40.6% had completed elementary education, and 14.6% held a graduate degree or higher. Regarding health issues, a significant proportion reported experiencing hearing difficulties (75.7%), tinnitus (63.4%), headaches (55.3%), and hypertension (47.2%). Regarding tenure at the power loom industry, 8.13% of workers had less than 5 years of service, 28.4% had worked for 6–10 years, 43.08% had 11–15 years of service, and 20.3% had more than 15 years of experience. All workers adhered to an 8-h work shift each day, and none utilized personal protective devices (PPDs) during working hours.

Table 1.

Socio-demographic characteristics of power loom industry workers

Variables	Frequency (%)
Demographic factors
Gender
Male	87 (70.73)
Female	38 (29.2)
Age
< 30 years	23 (18.6)
31–50 Years	45 (36.5)
> 50Years	55 (44.7)
Educational level
Illiterate	55 (44.7)
Elementary level	50 (40.6)
Secondary level	18 (14.6)
Health issues
Hearing difficulty
Yes	93 (75.7)
No	30 (24.3)
Tinnitus
Yes	78 (63.4)
No	45 (36.6)
Headache
Yes	68 (55.3)
No	55 (44.7)
Hypertension
Yes	58 (47.2)
No	65 (52.8)
Factors associated with noise exposure
Service duration in power-loom industry
< 5	10 (8.13)
6–10	35 (28.4)
11–15	53 (43.08)
> 15	25 (20.3)
Noise exposure level
< 95 dB (A)	3 (2.4)
> 95 dB (A)	120 (97.6)

Noise Exposure Levels and Frequency Distribution in Power-Loom Industry

Among the workers, the vast majority, comprising 97.6%, were exposed to noise levels of 95 dB (A) or higher, while only 2.4% were exposed to levels below this threshold. The noise levels recorded in the weaving section are depicted in Fig. 1. The average noise exposure over an 8-h Time-Weighted Average (TWA) period was 97.85 dB (A), with a standard deviation of 1.75 dB (A). The range of noise exposure observed in the power loom industry varied from 93.78 dB (A) to 107.25 dB (A).

Fig. 1.

The 24 h average noise concentration in the power-loom industry

Hearing Impairment Among Workers

The prevalence of hearing loss among the workers is illustrated in Table 2. Among all participants, 71.6% exhibited some degree of hearing loss, while 28.4% had normal hearing. Among those with hearing loss, 20.6% experienced impairment in both ears, 30.6% on the right side only, and 48.8% on the left side only. Figure 2 displays the hearing threshold levels exceeding 35 dB at high frequencies in both the left and right ears.

Table 2.

Hearing Impairment among power loom industry workers

Variables	Frequency (%)
Hearing loss
Present	88 (71.6)
Absent	35 (28.4)
Effected side of loss
Both sides	13 (20.6)
Right side	50 (30.6)
Left side	60 (48.8)

Fig. 2.

Audiometry results showing hearing impairment among power loom worker

Factors Associated with Hearing Loss

The factors associated with hearing loss among the workers is presented in Table 3. Individuals aged between 31 and 50 years (OR 3.58, 95% CI 0.82—2.48) and those over 50 years old (OR 5.7, 95% CI 2.43—12.42), as well as those with less than an elementary education level (OR 4.28, 95% CI 1.58—5.73), were significantly more likely to experience hearing impairment. Additionally, workers who reported hearing difficulty (OR 5.72, 95% CI 1.98—12.28), tinnitus (OR 4.23, 95% CI 0.52—3.19), or hypertension (OR 3.32, 95% CI 0.73—8.41) were also significantly associated with hearing loss. Furthermore, individuals with over 15 years of service duration in the power loom mill (OR 5.35, 95% CI 1.97—11.83) and those exposed to noise levels exceeding 95 dB (OR 4.21, 95% CI 2.28—8.93) were significantly more likely to experience hearing impairment.

Table 3.

Factors associated with hearing impairment among power loom industry workers

Variables	Hearing impairment N (%)		Bivariate analysis
	Present	Absent	p value	OR (95%CI)
Demographic factors
Gender
Male	67 (54.47)	20 (16.26)	0.22	1.2 (0.48–1.97)
Female	20 (16.26)	18 (14.63)	0.32	1.8 (2.42–5.78)
Age
< 30 years	5 (4.06)	18 (14.63)		1.00
31–50 Years	30 (24.39)	15 (12.19)	0.01	3.58 ( 0.82–2.48)*
> 50Years	45 (36.58)	10 (8.13)	0.001	5.7 (2.43 -12.42)*
Educational level
Illiterate	40 (32.52)	15 (12.19)	0.01	4.28 (1.58–5.73)*
Elementary level	30 (24.39)	20 (16.26)		0.23 (0.36–1.57)
Secondary level	10 (8.13)	8 (6.5)		0.72 (1.16–4.37)
Health issues
Hearing difficulty
Yes	85 (69.10)	8 (6.5)	0.001	5.72(1.98–12.28)*
No	2 (1.62)	28 (22.76)		1.00
Tinnitus
Yes	72 (58.53)	6 (4.87)	0.01	4.23 (0.52–3.19)*
No	42 (34.14)	3 (2.43)		1.00
Headache
Yes	60 (48.78)	8 (6.5)	0.45	1.23(0.48–1.55)
No	53 (43.08)	2 (2.43)		1.00
Hypertension
Yes	50 (40.6)	8 (6.5)	0.01	3.32(0.73–8.41)*
No	63 (51.2)	2 (2.43)		1.00
Factors associated with noise exposure
Service duration in power loom industry
< 5	2 (1.62)	8 (6.5)		1.00
6–10	30 (24.39)	5 (4.06)		1.19(0.68–3.82)
11–15	50 (40.65)	3 (2.43)	0.01	4.92 (0.72–6.35)*
> 15	22 (17.88)	3 (2.43)	0.001	7.35 (1.97–11.83)*
Noise exposure level
< 95 dB (A)	3 (2.43)	1 (0.8)		1.00
> 95 dB (A)	101 (82.11)	19 (15.44)	0.001	4.21 (2.28–8.93)*

*p-value ≤ 0.05,  OR = odd ratio

Discussion

Noise-induced hearing loss (NIHL) represents a critical occupational health issue with significant economic implications, particularly in South Asian countries [27]. Despite being entirely preventable, NIHL remains a prevalent concern. This study unveiled that the average age of the workers under investigation was 37.23 years, with an age range spanning from 20 to 60 years. Notably, these findings closely resemble those reported in similar studies conducted in other regions. For instance, research conducted in Ethiopia documented a mean age of 34.3 years among workers [27, 28], while studies in Thailand reported a comparable average age of 33.8 years [29, 30]. Moreover, investigations in Thailand [31] and Turkey [32] have consistently highlighted that the majority of workers fall within the age group of 31–40 years. This demographic trend may be attributed to the labor-intensive nature of employment prevalent in various industries. Furthermore, findings from studies conducted in various countries shed further light on the widespread prevalence of NIHL and its associated demographic patterns. For instance, research in Northern India has emphasized the alarming prevalence of NIHL among industrial workers, underscoring the urgent need for comprehensive preventive measures [33]. Similarly, studies in Bangladesh have highlighted the significant burden of NIHL among workers in textile and garment industries, pointing to the necessity for robust hearing conservation programs [34]. In neighboring Pakistan, investigations have revealed similar trends, emphasizing the imperative of implementing effective noise control measures and promoting awareness about the risks of occupational noise exposure [21].

All workers assigned to weaving sections adhered to an 8-h work shift within the textile mill premises. This duration is in line with findings from a study conducted in Pakistan, where workers also reported working 8 h per day with a daily break of 72 min [35]. Moreover, this practice aligns with the recommended exposure limit for noise stipulated by the National Institute for Occupational Safety and Health (NIOSH). Legislative frameworks further reinforce this standardization of working hours. In India, for instance, the Factories Act of 1951 stipulates that normal working hours should not exceed 8 h per day or 44 or 48 h per week, depending on whether the process is continuous or otherwise [36]. This regulation is in accordance with international labor standards set forth by the International Labor Organization. It’s noteworthy that a significant proportion of workers reported having more than 10 years of service tenure within the textile mill. This finding is consistent with similar studies conducted in Bangladesh [37] and Turkey [32], underscoring the longevity of employment within this sector across various countries. Expanding our understanding globally, similar trends in working hours and service duration have been observed in other regions. For instance, research in Vietnam has highlighted the prevalence of 8-h work shifts among textile industry workers, with many individuals also reporting extended service durations [38]. In neighboring Nepal, studies have also documented adherence to 8-h work shifts and prolonged service tenure among workers in the textile sector [39]. These findings collectively underscore the standardized nature of working hours and the enduring commitment of workers within the textile industry, both in South Asia and beyond.

To mitigate noise exposure and safeguard workers’ hearing health, the use of hearing protectors such as earmuffs, earplugs, and ear canal caps is recommended, particularly in instances where engineering controls and work practices are insufficient [40, 41]. Surprisingly, in this study, none of the workers were observed wearing Personal Protective Devices (PPDs) in the workplace, despite their availability. This observation suggests a potential lack of awareness among workers regarding the risks of Noise-Induced Hearing Loss (NIHL) and the importance of self-protective measures through PPD usage. Similar observations have been reported in studies conducted in other regions [42]. For instance, a study in Nigeria found that a significant number of workers who did not use hearing protectors reported experiencing hearing loss [3]. These findings underscore the critical importance of enforcing occupational safety and health regulations to ensure the proper use of hearing protectors in workplaces where noise exposure reaches or exceeds 95 dB(A) as an 8-h Time-Weighted Average (TWA). Furthermore, similar challenges related to PPD usage and awareness of NIHL risks have been observed in various countries. For example, research in Bangladesh has highlighted gaps in PPD utilization among workers in textile industries, despite the availability of protective equipment [43]. In Vietnam, studies have also reported low levels of awareness regarding NIHL prevention measures and inadequate PPD usage among workers in noisy work environments [38].

The prevalence of hearing loss observed in this study, at 71.6%, surpassed rates reported in other regions. For instance, studies conducted in Jordan [44] documented a prevalence of 40%, while in Turkey [45], it about 30.86%. Similarly, in Bangladesh [46], Ethiopia [47], and Canada [48], prevalence rates were reported as 33.46%, 34%, and 35%, respectively. These variations in hearing loss prevalence may be attributed to several factors, including differences in the implementation of hearing loss prevention programs. In this study, all workers exposed to unprotected 8-h Time-Weighted Average (TWA) noise levels equal to or exceeding 95 dB (A) underwent assessment of noise exposure and audiometric monitoring as part of these programs. This proactive approach to monitoring and managing noise exposure levels could have contributed to the higher prevalence observed. Conversely, in regions where hearing loss prevalence rates were lower, the implementation of such comprehensive prevention programs may have been lacking or less robust [13]. Additionally, differences in occupational health and safety regulations, as well as variations in workplace practices and awareness initiatives, could also have influenced the observed disparities in hearing loss prevalence across different countries.

Age-related hearing loss, known as presbycusis, emerges as a prevalent cause of high-frequency hearing impairment, typically beginning around the age of forty [49, 50]. Within the context of this study, workers aged 50 years and above exhibited a 5.7-fold increased likelihood of experiencing hearing loss compared to those under the age of 30. This association remained significant even after adjusting for service duration, aligning with findings from a similar study conducted in Ethiopia [51]. Presbycusis, characterized by gradual hearing loss in older individuals, likely underpins this observed relationship. Consistent with these findings, studies conducted in various regions have also highlighted the positive association between age and hearing loss [52]. For instance, research in Canada [48], and Brazil [53] have documented similar trends, further underscoring the impact of age-related factors on hearing health. Furthermore, studies conducted in Southeast Asian and African countries have also reported similar associations between age and hearing loss. Research in Vietnam, for example, found that older individuals were more likely to experience age-related hearing impairment compared to younger counterparts [38]. Similarly, investigations in Nigeria have highlighted the prevalence of age-related hearing loss among older adults, with increasing age serving as a significant risk factor [54].

Workers with less than a secondary school education level face a heightened risk of developing hearing loss compared to those with a secondary school education level or higher. This disparity may stem from various factors, including a lack of understanding of safety protocols, challenges in comprehending warning labels and machine instructions, and limited participation in hazard communication programs among individuals with lower educational attainment levels [13, 55]. A parallel observation was made in United Kingdom, where a high prevalence of severe hearing difficulty was noted among noise-exposed workers [56]. These findings underscore the critical importance of educational initiatives and effective communication strategies in promoting hearing health and mitigating the risk of occupational hearing loss.

Tinnitus (Ringing in ears) poses a significant challenge for individuals exposed to high levels of noise in the workplace, impacting various aspects of their lives including sleep, concentration, mood, and overall quality of life [57]. As a persistent background noise or ringing sensation, tinnitus can be perceived as a minor annoyance, yet its effects can be far-reaching [58]. Prolonged exposure to loud noise is known to trigger tinnitus, and it can also exacerbate existing hearing loss, leading to further deterioration of hearing function. Notably, individuals with hearing loss may not immediately notice changes in their hearing abilities until a significant threshold shift has occurred. Unfortunately, this shift is often irreversible and tends to worsen with continued exposure to hazardous noise levels [59]. In this study, workers who reported experiencing current tinnitus were found to be three times more likely to develop hearing loss compared to those who did not report such symptoms. This finding is consistent with research conducted in Canada, which highlighted a high prevalence of tinnitus among workers exposed to hazardous noise levels [48]. Additionally, studies conducted in other regions have also documented the adverse impact of tinnitus among noise-exposed workers. Research in Indonesia, for instance, found a significant association between occupational noise exposure and the prevalence of tinnitus among workers in noisy environments [60]. Similarly, investigations in Kenya have reported a high prevalence of tinnitus among individuals working in industries with elevated noise levels, underscoring the need for effective preventive measures and interventions [61]. These findings underscore the importance of addressing tinnitus as a critical occupational health concern, particularly among workers exposed to hazardous noise levels [62].

Regarding high blood pressure, a higher prevalence of hearing loss was observed among workers with hypertension [63]. Research has indicated a significant elevation in blood pressure levels among workers exposed to occupational noise [64, 65]. Similarly, a study conducted in Taiwan highlighted a positive correlation between noise levels and blood pressure levels [66]. In the current study, the risk of hearing loss was found to be 3.32 times higher among workers with hypertension compared to those without hypertension, consistent with the findings of these previous studies. Research in Malaysia, for instance, found an increased prevalence of hearing loss among workers with hypertension in noisy workplaces [67]. Similarly, investigations in South Africa have reported elevated blood pressure levels among individuals exposed to occupational noise, suggesting a potential link with hearing impairment [68]. These results highlights the interconnected nature of hypertension, occupational noise exposure, and hearing loss, highlighting the importance of comprehensive health monitoring and intervention strategies in occupational settings.

Exposure to extremely loud noise, whether occurring as a single event or over an extended period, can lead to hearing loss. Prolonged exposure to continuous noise can result in progressive and irreversible hearing impairment affecting both ears [69]. The incidence of hearing loss tends to be notably higher among individuals with prolonged work experience in noisy industries. In this study, workers with more than 15 years of service in the textile mill were found to be 7.35 times more likely to experience hearing loss compared to those with 10 years or less of service duration. This trend aligns with findings from research conducted in various countries such as Thailand [70], Ethiopia [71], Bangladesh [37], and Saudi Arabia [72], where employment tenure extended was associated with an increased risk of hearing loss among workers. To safeguard against hearing loss, the National Institute for Occupational Safety and Health (NIOSH) has set guidelines limiting exposure to noise levels of 95 dB (A) and above. It was anticipated that workers exposed to noise levels exceeding this threshold would be at greater risk of developing hearing loss compared to those exposed to levels below 95 dB (A). Studies conducted in countries like Thailand [31], Ethiopia [73], and Jordan [74] have indeed reported a significant association between noise exposure levels and the prevalence of hearing loss. However, in this study, no significant association was found between noise exposure levels and hearing loss. Research in Iran has indicated a notable prevalence of hearing loss among workers exposed to high noise levels in industrial settings [75]. Similarly, investigations in Turkey have reported a significant correlation between noise exposure duration and the incidence of hearing impairment among textile industry workers [45]. Results of this study might be generalized to elsewhere in which the workers are employed in same occupational setting. However, if the implementation of occupational safety and health regulations is different (even in other occupational settings located in different regions/ states), the study results might be varied, particularly among those with diversity of demographic factors, risk behaviors, health problems, and consciousness on NIHL.

Conclusion

In conclusion, this study sheds light on the significant prevalence of hearing loss among power loom workers in the Erode district of Tamil Nadu, India, and underscores the urgent need for comprehensive preventive measures. The findings reveal a high prevalence of hearing loss among workers, with 71.6% experiencing some degree of impairment. Factors significantly associated with hearing loss include older age, lower educational attainment, presence of health issues such as hypertension and tinnitus, prolonged service duration in the textile mill, and exposure to high noise levels exceeding 95 dB(A). Despite the availability of hearing protectors, none of the workers utilized personal protective devices (PPDs), highlighting a critical gap in awareness and adherence to safety protocols. This emphasizes the importance of enforcing occupational safety and health regulations to ensure proper PPD usage in noisy workplaces. The study underscores the interconnected nature of various risk factors contributing to hearing loss among industrial workers. It emphasizes the need for targeted interventions aimed at raising awareness, promoting the use of PPDs, and implementing effective noise control measures to mitigate occupational noise exposure. Furthermore, the study highlights the need for comprehensive hearing conservation programs and the development of coordinated national initiatives to address the burden of noise-induced hearing loss in industrial settings. Such efforts are crucial for safeguarding the hearing health and overall well-being of workers, ultimately contributing to a safer and healthier work environment.

Author’s contributions

All authors contributed equally to the study.

Funding

This work was supported by Indian Council of Medical Research (F.No. 11013/17/2023-GIA/HR). Shankar Subramaniam and Naveenkumar Raju has received research support from Department of Health Research, ICMR, New Delhi.

Data availability

The data underlying this article will be shared on reasonable request to the corresponding author.

Declarations

Conflicts of interest

The authors declare that they have no competing interests.

Consent to Participate

Informed consent was obtained from all individual participants included in the study.

Consent to Publish

Consent was obtained from all individual participants to publish without informing their names.

Ethical Approval

This study was approved by Institute Ethics Committee with the Reference number (KEC/R&D/EC/2022–23/003).