Noise Exposure and Hearing Loss in Agriculture: A Survey of Farmers and Farm Workers in the Southland Region of New Zealand

Hearing Difficulties Among Farmworkers in the México-US Southwest Border Region

Migrant and seasonal farmworkers are a vulnerable population with a potentially high risk for hearing loss due to farm-related noise exposures. Occupational noise-induced hearing loss (NIHL) is permanent, and it is associated with an increased risk for injuries on the job, as well as communication difficulties, isolation, and depression. The México/US border region is one of the most productive agricultural regions in the country, however, no known studies have explored hearing loss among farmworkers in this area. This pilot study was a first step toward measuring and addressing hearing loss and noise exposure among this region's farmworkers. We conducted a cross-sectional survey to estimate the prevalence of subjective hearing difficulties among Yuma County, Arizona farmworkers. Survey interviews took place during a late-night farmworker health fair from 2 am to 6 am to accommodate local farms' labor schedules. Multivariable regression adjusted for demographic and work covariates estimated subjective hearing loss prevalence ratios. Among 132 farmworker participants, 36% reported they have or might have hearing loss, and 62% reported no hearing loss. Subjective hearing loss prevalence was lower in farmworkers who report not working in noise compared to prevalence in farmworkers who work in noise [prevalence ratio, 0.44 (95% CI 0.23-0.82)]. This report contributes to understanding the perception of hearing-related health and occupational exposures among farmworkers in the México-US Southwest border region. The information from this line of research will inform appropriate safety measures known to lower the risk of experiencing occupational NIHL.

Noise exposure and hearing loss among tractor drivers in India

BACKGROUND

Tractors emit high intensity noise and prolonged exposure to high intensity noise causes hearing loss to the drivers.

OBJECTIVE

The aim of this study was to measure noise intensity at the tractor drivers' ear level and hearing loss among tractor drivers.

METHODS

Noise intensity was measured on 6 models of tractors which were operated with 5 different tillage implements. In order to assess hearing loss, audiometric test was performed at 7 frequencies, i.e. 250, 500, 1000, 2000, 4000, 6000, and 8000 Hz, among 30 tractor drivers and 30 control group subjects. All the selected tractor drivers and control group subjects were also interviewed to obtain personal information and noise exposure details.

RESULTS

The tractor drivers were exposed to noise intensity in the range of 91.7-97.5 dB(A). Audiogram analysis shows that the hearing threshold levels were significantly (p < 0.05) higher among the tractor drivers as compared with the control group subjects. The effect was significantly (p < 0.05) more on the left ear as compared with the right ear among the tractor drivers. Increase in age has significant (p < 0.05) effect on the hearing threshold levels on the left ear. Prevalence of high frequency hearing loss was 50% among tractor drivers as compared with 10% among control group subjects. Hearing loss was significantly (p < 0.05) more in the low frequency as compared with the high frequency among the tractor drivers.

CONCLUSION

Indian tractor operators are exposed to high noise levels which may result in hearing loss. It is recommended that hearing conservation programs should be initiated to prevent noise hazards and hearing loss among the tractor drivers.

Hearing Difficulties and Tinnitus in Construction, Agricultural, Music, and Finance Industries: Contributions of Demographic, Health, and Lifestyle Factors

High levels of occupational noise exposure increase the risk of hearing difficulties and tinnitus. However, differences in demographic, health, and lifestyle factors could also contribute to high levels of hearing difficulties and tinnitus in some industries. Data from a subsample (n = 22,936) of the U.K. Biobank were analyzed to determine to what extent differences in levels of hearing difficulties and tinnitus in high-risk industries (construction, agricultural, and music) compared with low-risk industries (finance) could be attributable to demographic, health, and lifestyle factors, rather than occupational noise exposure. Hearing difficulties were identified using a digits-in-noise speech recognition test. Tinnitus was identified based on self-report. Logistic regression analyses showed that occupational noise exposure partially accounted for higher levels of hearing difficulties in the agricultural industry compared with finance, and occupational noise exposure, older age, low socioeconomic status, and non-White ethnic background partially accounted for higher levels of hearing difficulties in the construction industry. However, the factors assessed in the model did not fully account for the increased likelihood of hearing difficulties in high-risk industries, suggesting that there are additional unknown factors which impact on hearing or that there was insufficient measurement of factors included in the model. The levels of tinnitus were greatest for music and construction industries compared with finance, and these differences were accounted for by occupational and music noise exposure, as well as older age. These findings emphasize the need to promote hearing conservation in occupational and music settings, with a particular focus on high-risk demographic subgroups.

Noise Exposure on Mixed Grain and Livestock Farms in Western Australia

Noise presents an ongoing occupational health and safety issue, which despite numerous studies still presents a significant risk in agriculture with high exposures prevalent. In this study, we measured noise exposures associated with significant activities on 42 mixed grain and livestock farms in Western Australia. Employing a mixture of personal noise measurements using dosimeters, noise measurements using sound level meters, and a validated survey, we identified that 32% of farm workers were exposed to noise levels above the LAeq,8h 85 dB(A) limit, before considering extended shifts. We also noted that extended shift lengths, of up to 16 h in some cases, were possible. In addition, we found that 37% of workers were exposed to noise peak of 140 dB(C) or greater. It was further noted that hearing protection is not typically worn for the duration of an activity and is only for a small number of tasks. However we did find some evidence that farmers had begun to implement some form of noise management practice, usually in the form of buying quieter equipment or separating noisy tasks from quiet tasks. Improved education for farmer and farm workers in terms of the risks posed by noise, identifying noisy tasks, is recommended, as well as a programme to encourage better and consistent use of hearing protection.

Hearing Loss in Agricultural Workers Exposed to Pesticides and Noise

Agricultural workers who have concurrent exposure to pesticides and noise are at increased risk of hearing loss. We recruited 163 Thai conventional and 172 organic farmers to answer our questionnaires about personal demographics, agricultural activities, and pesticide and agricultural machinery use. This information was used to calculate the years of conventional (pesticide use) farming and the years of agricultural noise exposure, and to estimate semiquantitative metrics for pesticide exposure (cumulative intensity score-years) and cumulative noise exposure (dB(A)-years) for each conventional farmer. All participants underwent pure tone audiometric testing. The mean hearing threshold in the low-frequency band (0.5-2 kHz) and high-frequency band (3-6 kHz) were used for analysis. Years involved in conventional farming and years using agricultural machinery were associated with an increase in the average hearing threshold for the high-frequency band after controlling for age, ever exposed to industrial noise and cigarette smoking. The highest category of cumulative insecticide exposure (score-years), cumulative organophosphates exposure (score-years) and cumulative noise exposure (dB(A)-years) were also associated with an increased high-frequency band hearing threshold among conventional farmers. Results from the full cohort and the subcohort of conventional farmers support each other and the hypothesis that pesticide and noise have an additive effect on hearing, since no model interactions were significant.

"I Will Not Leave My Body Here": Migrant Farmworkers' Health and Safety Amidst a Climate of Coercion

Every year more temporary migrant workers come to Canada to fill labour shortages in the agricultural sector. While research has examined the ways that these workers are made vulnerable and exploitable due to their temporary statuses, less has focused on the subjective experiences of migrant agricultural workers in regards their workplace health and safety. We conducted interviews and focus groups with migrant workers in the interior of British Columbia, Canada and used a narrative line of inquiry to highlight two main themes that illustrate the implicit and complex mechanisms that can structure migrant agricultural workers’ workplace climate, and ultimately, endanger their health and safety. The two themes we elaborate are (1) authorities that silence; and (2) “I will not leave my body here.” We discuss the implications of each theme, ultimately arguing that a number of complex political and economic forces create a climate of coercion in which workers feel compelled to choose between their health and safety and tenuous economic security.

Questionnaire-based algorithm for assessing occupational noise exposure of construction workers

Objectives

Occupational noise exposure is a major cause of hearing loss worldwide. In order to inform preventative strategies, we need to further understand at a population level which workers are most at risk.

Methods

We have developed a new questionnaire-based algorithm that evaluates an individual worker’s noise exposure. The questionnaire and supporting algorithms are embedded into the existing software platform, OccIDEAS. Based on the tasks performed by a worker during their most recent working shift and using a library of task-based noise exposure levels, OccIDEAS estimates whether a worker has exceeded the full-shift workplace noise exposure limit (LAeq,8h≥85 dBA). We evaluated the validity of the system in a sample of 100 construction workers. Each worker wore a dosimeter for a full working shift and was then interviewed using the OccIDEAS software.

Results

The area under the receiver operating characteristic curve was 0.81 (95% CI 0.72 to 0.90) indicating that the ability of OccIDEAS to identify construction workers with an LAeq,8h≥85 dBA was excellent.

Conclusion

This validated noise questionnaire may be useful in epidemiological studies and for workplace health and safety applications.

Gender differences in use of hearing protection devices among farm operators

Purpose:

Although farm operators have frequent exposure to hazardous noise and high rates of noise-induced hearing loss, they have low use of hearing protection devices (HPDs). Women represent about one-third of farm operators, and their numbers are climbing. However, among published studies examining use of HPDs in this worker group, none have examined gender-related differences. The purpose of this study was to examine gender-related differences in use of hearing protection and related predictors among farm operators.

Materials and Methods:

Data previously collected at farm shows and by telephone were analyzed using t-tests and generalized linear model with zero inflated negative binomial (ZINB) distribution.

Findings:

The difference in rate of hearing protector use between men and women farm operators was not significant. There was no difference between men and women in most hearing protector-related attitudes and beliefs.

Conclusion:

Although men and women farm operators had similar rates of use of hearing protectors when working in high-noise environments, attitudes about HPD use differed. Specifically, interpersonal role modeling was a predictor of HPD use among women, but not for men. This difference suggests that while farm operators of both genders may benefit from interventions designed to reduce barriers to HPD use (e.g., difficulty communicating with co-workers and hearing warning sounds), farm women have unique needs in relation to cognitive-perceptual factors that predict HPD use. Women farm operators may lack role models for use of HPDs (e.g., in peers and advertising), contributing to their less frequent use of protection.

Evaluation of noise-induced hearing loss by auditory steady-state and auditory brainstem-evoked responses

OBJECTIVES

Noise-induced hearing loss (NIHL) may result from occupational noise exposures and is considered as an 'Occupational Disease'; therefore, it is compensable. To verify the existence and severity of the work-related hearing loss, there is a need of an objective, reliable auditory measure in cases of arbitration of financial disputes to resolve any medicolegal aspects. The objective of the study was to compare between the ABR and ASSR for predicting the behavioural threshold in subjects with normal hearing or NIHL.

DESIGN

The study included 82 subjects regularly exposed to high levels of occupational noise, with normal hearing and NIHL. ABR to clicks and to tone bursts were recorded followed by multiple-frequency ASSR. Physiological and behavioural thresholds were compared for specific frequencies (1000, 2000 Hz) and average of high-frequency range (2000 and 4000 Hz). In addition, Pearson correlations and the specificity and sensitivity of each measure were also calculated using receiver operating characteristic (ROC) curves.

RESULTS

In the NIHL group, there was a significantly smaller difference between the behavioural threshold and click-ABR than the ASSR in high-frequency range. Pearson correlations were significantly higher for click-ABR. Analysis of specific frequencies yielded a smaller difference between behavioural and ASSR than tone-burst-ABR thresholds, with a slightly better correlation for ASSR than tone-burst-ABR. Higher sensitivity but lower specificity was suggested for ASSR than ABR.

CONCLUSIONS

ASSR is associated with high-frequency specificity, shorter test sessions and good correlations with behavioural thresholds, making it a potentially better measure than ABR for predicting audiograms in subjects with NIHL. These findings have diagnostic implications, especially in cases of workers' compensation when subjects may be uncooperative.

The Effect of Atorvastatin on Preventing Noise-Induced Hearing Loss: An Experimental Study

Background:

Noise-induced hearing loss (NIHL) is a common, irreversible occupational disease. Statins have recently been proposed to prevent NIHL.

Objective:

To assess the effect of atorvastatin for the prevention of NIHL in rats.

Methods:

In this experimental study, forty 2–3-month-old Wistar male rats were divided into 5 groups of 8 animals. 3 groups of rats received atorvastatin at doses of 5, 25, and 50 mg/kg daily for 14 days. The 4^th group of rats received normal saline; another group was the control group. After 2 weeks of treatment, the rats were exposed to broad-band noise (125– 20 000 Hz) at 110 dB-SPL intensity for 2 hours. Response amplitude of all ears at 5 frequencies was assessed by distortion product otoacoustic emissions (DP-OAE) at baseline, 2 hours, and 2 weeks after the exposure.

Results:

Response amplitude was significantly decreased at all frequencies immediately after exposure to noise in all studied groups. The amplitude increased after 72 hours to a level higher than temporary threshold shift (TTS); this change was only significant in the group received 5 mg/kg atorvastatin.

Conclusion:

Low dose atorvastatin (5 mg/kg) used before exposure to noise can probably prevent NIHL in rats. This effect was not observed with higher doses of the drug.

Assessment of Occupational Noise Exposure among Groundskeepers in North Carolina Public Universities

Groundskeepers may have increased risk to noise-induced hearing loss due to the performance of excessively noisy tasks. This study assessed the exposure of groundskeepers to noise in multiple universities and determined the association between noise exposure and variables (ie, university, month, tool used). Personal noise exposures were monitored during the work shift using noise dosimetry. A sound level meter was used to measure the maximum sound pressure levels from groundskeeping equipment. The mean Occupational Safety and Health Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH) time-weighted average (TWA) noise exposures were 83.0 ± 9.6 and 88.0 ± 6.7 dBA, respectively. About 52% of the OSHA TWAs and 77% of the NIOSH TWAs exceeded 85 dBA. Riding mower use was associated with high TWA noise exposures and with having OSHA TWAs exceeding 85 and 90 dBA. The maximum sound pressure levels of equipment and tools measured ranged from 76 to 109 dBA, 82% of which were >85 dBA. These findings support that groundskeepers have excessive noise exposures, which may be effectively reduced through careful scheduling of the use of noisy equipment/tools.

Effects of interventions on use of hearing protectors among farm operators: A randomized controlled trial

OBJECTIVE

The purpose of this study was to compare the effectiveness of three interventions designed to promote hearing protector device (HPD) use.

DESIGN

Randomized controlled trial.

STUDY SAMPLE

Farm operators (n = 491) were randomly assigned to one of five intervention groups: (1) interactive web-based information with mailed assortment of HPDs; (2) Interactive web-based information only; (3) static web-based information with mailed assortment of HPDs; (4) Static web-based information only; or (5) mailed assortment of HPDs only. Data were analysed using a mixed model approach.

RESULTS

HPD use increased among all participants, and increased more among participants receiving the mailed HPDs (with or without information) compared to participants receiving other interventions. Participants receiving the interactive web-based information had comparable increased use of HPDs to those receiving the static web-based information. Participants receiving the mailed HPDs had more positive situational influences scale scores than other participants. Program satisfaction was highest among mailed and web-based information groups.

CONCLUSIONS

A mailed assortment of hearing protectors was more effective than information. Interactive and static information delivered via web were similarly effective. Programs interested in increasing HPD use among farmers should consider making hearing protectors more available to farmers.

Noise exposure assessment among groundskeepers in a university setting: A pilot study

Approximately 870,000 U.S. workers are employed as landscaping and groundskeeping workers who perform various tasks and use a variety of tools that expose them to high noise levels, increasing their risk to noise-induced hearing loss (NIHL). Several studies on noise exposure and NIHL in other job sectors have been published, but those on groundskeepers are very limited. This study aims to characterize the noise exposure of groundskeepers. Participants were monitored over their entire work shift for personal noise exposure by wearing noise dosimeters at shoulder level, 4 in from the ear. Using two different dosimeter settings (OSHA and NIOSH), the time-weighted averages (TWAs) and 1-min averages of noise exposure levels in decibels (dBA) were obtained. The participants were also asked to fill out an activity card daily to document their tasks, tools used, location and noise perception. Sound pressure levels (SPLs) produced by various groundskeeping equipment and tools were measured at full throttle near the ear of the operator using a sound level meter. These measurements were used to assess worker noise exposure profiles, particularly the contributing source of noise. The overall mean OSHA and NIOSH TWA noise exposures were 82.2±9.2 (range of 50.9-100 dBA) and 87.8±6.6 dBA (range of 67.2-102.9 dBA), respectively. Approximately 46% of the OSHA TWAs exceeded the OSHA action limit of 85 dBA. About 76% of the NIOSH TWAs exceeded 85 dBA, and 42% exceeded 90 dBA. The SPLs of equipment and tools measured ranged from 75- 106 dBA, most of which were at above 85 dBA and within the 90-100 dBA range. Hand-held power tools and ride-on equipment without enclosed cab may have contributed significantly to worker noise exposure. This study demonstrates that groundskeepers may be routinely exposed to noise levels above the OSHA and NIOSH exposure limits, and that the implementation of effective hearing conservation programs is necessary to reduce their risk to NIHL.

Social Desirability Bias in Self-Reporting of Hearing Protector Use among Farm Operators

OBJECTIVE

The purposes of this study were (i) to examine the relationship between reported hearing protector use and social desirability bias, and (ii) to compare results of the Marlowe-Crowne social desirability instrument when administered using two different methods (i.e. online and by telephone).

METHODS

A shortened version of the Marlowe-Crowne social desirability instrument, as well as a self-administered instrument measuring use of hearing protectors, was administered to 497 participants in a study of hearing protector use. The relationship between hearing protector use and social desirability bias was examined using regression analysis. The results of two methods of administration of the Marlowe-Crowne social desirability instrument were compared using t-tests and regression analysis.

RESULTS

Reliability (using Cronbach's alpha) for the shortened seven-item scale for this sample was 0.58. There was no evidence of a relationship between reported hearing protector use and social desirability reporting bias, as measured by the shortened Marlowe-Crowne. The difference in results by method of administration (i.e. online, telephone) was very small.

CONCLUSIONS

This is the first published study to measure social desirability bias in reporting of hearing protector use among farmers. Findings of this study do not support the presence of social desirability bias in farmers' reporting of hearing protector use, lending support for the validity of self-report in hearing protector use in this population.

Time of day and season affect the level of noise made by pigs kept on slatted floors

Abstract. The aim of this study was to prove the hypothesis that the noise emissions from pig housing varies according to the time of day and the season. The measurements were performed in a building for 1150 fattening pigs with a slatted floor during summer and winter. The pigs (average weight 95 kg) were kept in pens under a batch management system. Nine places were the focus of sound intensity measurements (one inside the stable in section 7; eight places outside the building). The measurements were performed during three sets of 5 consecutive days in summer and three sets in winter. On each day the data were obtained during three 30 min periods (before feeding, during feeding and after feeding). The measurement was made inside and outside the building at the same time. The level of noise depends very significantly upon the period of measurement (before feeding, during feeding, after feeding). The following values were recorded inside (place 1): 65.5 ± 1.6 dB before feeding, 72.0 ± 1.4 dB during feeding and 63.4 ± 0.7 dB after feeding (P < 0.001). The effect of seasonal noise levels can be seen only in outside measurements (P < 0.05; P < 0.01). The comparison of measurement place 1 (inside, pen with pigs) with the other places outdoors showed significant differences in both observed factors (P < 0.001). We can conclude that the noise in the pig housing depends significantly on the time of day. The season influences the noise outside the building, in particular.

Noise exposure of workers and the use of hearing protection equipment in New Zealand

Hearing loss from occupational noise exposure is a significant occupational health problem, requiring effective health and safety strategies. Essential to this is an understanding of the noise exposure of workers and the use of hearing protection equipment (HPE). This study reports on data collected in New Zealand. Visits were made to companies in each economic sector. Personal dosimetry was used to assess individual noise exposure of 529 workers. Workers were also interviewed about their use of HPE. Overall, 40.4% of production workers had a daily noise exposure greater than 1 Pa(2)h, exceeding the New Zealand National Standard for occupational noise exposure without HPE. Of these, 88.5% reported to use HPE when working in noise; however, some observations suggested that workers do not consistently use the devices. These data add to the overall picture of noise exposure of workers in New Zealand and are especially useful in areas where data did not previously exist or were difficult to access.

Effect of workplace noise on hearing ability in tile and ceramic industry workers in Iran: a 2-year follow-up study

INTRODUCTION

Noise as a common physical hazard may lead to noise-induced hearing loss, an irreversible but preventable disorder. Annual audiometric evaluations help detect changes in hearing status before clinically significant hearing loss develops. This study was designed to track hearing threshold changes during 2-year follow-up among tile and ceramic workers.

METHODS

This follow-up study was conducted on 555 workers (totally 1110 ears). Subjects were divided into four groups according to the level of noise exposure. Hearing threshold in conventional audiometric frequencies was measured and standard threshold shift was calculated for each ear.

RESULTS

Hearing threshold was increased during 2 years of follow-up. Increased hearing threshold was most frequently observed at 4000, 6000, and 3000 Hz. Standard threshold shift was observed in 13 (2.34%), 49 (8.83%), 22 (3.96%), and 63 (11.35%) subjects in the first and second years of follow-up in the right and left ears, respectively.

CONCLUSIONS

This study has documented a high incidence of noise-induced hearing loss in tile and ceramic workers that would put stress on the importance of using hearing protection devices.

Effects of common agricultural tasks on measures of hearing loss

BACKGROUND

Among agricultural populations, hearing loss caused by excessive noise exposure is common. However, examinations of associations between exposure to agricultural tasks and hearing loss are limited.

METHODS

Audiometry and lifetime exposure to 11 agricultural tasks were analyzed among 1,568 participants. Gender stratified multivariable linear regression was used to estimate associations between exposure duration and three hearing loss metrics.

RESULTS

Among men, significant associations were observed between hearing loss and hunting or target shooting, all-terrain vehicle (ATV) or motorcycle riding, chain saw use, electric or pneumatic tool use, living on a farm, and all agricultural tasks combined. When all significant exposure metrics were included in a single model, associations remained for hunting or target shooting, electric or pneumatic tool use and living on a farm. Significant associations were sparse among women, and in all cases paradoxical.

CONCLUSIONS

Despite imprecise estimation of noise exposure, specific agricultural tasks were associated with hearing loss.

The injured and diseased farmer: occupational health, embodiment and technologies of harm and care

Occupational health in agriculture is a significant public health issue in industrialised agricultural nations. This article reports on 26 in-depth interviews with farmers throughout New Zealand. Farmers are exposed to a range of technologies which place them at risk of injury and disease and/or prevent injury and disease. In this article these technologies are respectively conceptualised as technologies of harm and technologies of care. Despite being vulnerable to high rates of injury, fatality and occupationally related diseases the uptake of technologies of care amongst farmers in New Zealand is poor. The analysis draws on body theory to explore the meaning attached to injury and disease and to examine the socio-cultural field of agriculture. It is argued that the key features of subjective embodiment and social, cultural and symbolic capital can undermine the uptake of technologies of care, ensuring poor occupational health outcomes on New Zealand farms.

Noise exposures of rural adolescents

PURPOSE

This project was conducted to characterize the noise exposure of adolescents living in rural and agricultural environments.

METHODS

From May to October, 25 adolescents ages 13 through 17, living either on a farm or a rural nonfarm, were enrolled in the study. Subjects received training on the correct operation and use of personal noise dosimeters and the proper way to record their daily tasks on activity cards. Subjects completed 4 days of self-monitoring noise dosimetry, 2 days in the first round (May-July) and 2 days in the second round (August-October). In addition to dosimetry, subjects completed activity logs of their daily tasks.

RESULTS

The mean daily noise exposures of adolescents living on farms and in nonfarm rural homes were between 55.4 dBA (A-weighted decibels) and 103.5 dBA, with 44% of the daily measurements greater than the National Institute of Occupational Safety and Health Recommended Exposure Level of 85 dBA. Task-based analysis of noise exposures found that activities involving mechanized equipment resulted in the highest exposures, while activities in the home resulted in the lowest exposure. No particular demographic group had a statistically higher noise exposure; therefore, specific factors apart from activities and noise sources could not be identified as risk factors for exposure to hazardous noise levels.

CONCLUSIONS

The results of this project indicate that rural adolescents complete a variety of activities and are exposed to noise sources with a broad range of decibel levels. While the exposures may change from day to day, there are occasions when exposure to noise exceeds the recommended levels.

Effects of a low intensity intervention to increase hearing protector use among noise-exposed workers

BACKGROUND

Farm operators experience exposure to high noise and high prevalence of noise-induced hearing loss, but use of hearing protection in this worker group is low. The purpose of this study was to test a brief intervention to increase farm operators' use of hearing protection.

METHODS

In this one-group pre- and post-test study, a random sample of 32 members of a farmers' organization was supplied a variety of hearing protectors. Participants received an assortment of hearing protectors by mail with manufacturer's instructions for use.

RESULTS

Mean pre-intervention hearing protector use when in high noise in this group was 23% (SD 29). Of the 32 participants, 27 (84%) were exposed to hazardous noise during the study period. Post-intervention mean use of HPDs was 64%, an increase of 41% (t = 5.26, P < 000).

CONCLUSION

Results of this study suggest that overall, hearing protectors were acceptable to farm operators, and that a brief mailed intervention is feasible.

Personal noise exposures of operators of agricultural tractors

Approximately one million agricultural tractors are used in Turkey for crop production and about one-third of the population lives in rural areas. The objectives of this study were to determine sound pressure levels, A-weighted sound pressure levels, and the permissible exposure time for tractors without cabins, field-installed cabins, and original cabins at ear level of agricultural tractor operators for following machines: plows, cultivators, top soil cultivators, rotary tillers, tool combinations (harrow+roller), mechanical drills, pneumatic drills, chemical applicators, fertilizer applicators, drum mowers, balers, and forage harvesters. Variance analyses showed that type of operation, type of cabins, and operation x cabin interactions were statistically significant (P<0.01) both for sound pressure levels and equivalent (A-weighted) sound pressure levels. The use of original cabins had a greater effect in decreasing average sound pressures and resulted in more efficient noise insulation, especially at higher center frequencies compared to field-installed cabins whereas field-installed cabins proved to be more favorable compared to tractors without cabins. Sound pressure levels at 4000Hz center frequency was reduced 2-13dB and 4-18dB by using a field-installed cabin and an original cabin, respectively. The measured A-weighted equivalent sound pressure levels were compared to the threshold limit level, and was concluded that depending on the cabin types used, the operators could usually work from 4 to 6h a day without suffering from noise induced inconveniences while 2-3h is permissible for plowing and forage harvesting on tractors without cabins. Due to timeliness considerations in agricultural machine operations, a farmer would not be willing to interrupt the operation based on permissible exposure time set by the standards. Based on the findings of this study, particularly an original cabin is recommended to reduce machine-induced noise below the danger limit during agricultural machine operations. Personal protection devices should be used when tractors are operated without cabins, which could reduce A-weighted equivalent sound pressure levels by 10-45dB(A).

The New Zealand workforce survey I: self-reported occupational exposures

INTRODUCTION

This study examines the prevalence of a range of occupational risk factors reported by a random sample of the New Zealand working population.

METHODS

Men and women aged 20-64 were selected from the New Zealand Electoral Roll and invited to take part in a telephone interview, which collected information on lifetime work history, current workplace exposures and organizational factors, and various health conditions. The prevalences of occupational risk factors in each occupational and industry group are reported.

RESULTS

Three thousand and three interviews were completed (37% of the eligible sample and 55% of those that could be contacted). Trades workers reported the highest prevalences of exposure to dust (75%) and oils and solvents (59%). Agriculture and fishery workers reported the highest prevalences of exposure to pesticides (63%) and acids or alkalis (25%). Plant and machine operators and assemblers reported the highest prevalences of exposure to smoke/fume/gas (43%), working night shift in the previous 4 weeks (18%), and working irregular hours (33%). In the high exposure occupational and industry groups, males reported a higher prevalence of exposure than females. Lifting, exposure to loud noise, and the use of personal protective equipment were reported by >50% of the manual occupational groups.

CONCLUSIONS

This study indicates that occupational exposure to risk factors for work-related disease and injury remains common in the New Zealand working population. While these occupational exposures are disproportionately experienced by workers in certain industries, they also occur in occupational groups not traditionally associated with hazardous exposures or occupational disease.

Exposure to hazardous workplace noise and use of hearing protection devices among US workers--NHANES, 1999-2004

BACKGROUND

To estimate the prevalence of workplace noise exposure and use of hearing protection devices (HPDs) at noisy work, NIOSH analyzed 1999-2004 data from the National Health and Nutrition Examination Survey (NHANES).

METHODS

A total of 9,275 currently employed workers aged > or =16 years were included in the weighted analysis. Hazardous workplace noise exposure was defined as self-reported exposure to noise at their current job that was so loud that the respondent had to speak in a raised voice to be heard. Industry and occupation were determined based on the respondent's current place and type of work.

RESULTS

Twenty-two million US workers (17%) reported exposure to hazardous workplace noise. The weighted prevalence of workplace noise exposure was highest for mining (76%, SE = 7.0) followed by lumber/wood product manufacturing (55%, SE = 2.5). High-risk occupations included repair and maintenance, motor vehicle operators, and construction trades. Overall, 34% of the estimated 22 million US workers reporting hazardous workplace exposure reported non-use of HPDs. The proportion of noise-exposed workers who reported non-use of HPDs was highest for healthcare and social services (73.7%, SE = 8.1), followed by educational services (55.5%).

DISCUSSION

Hearing loss prevention and intervention programs should be targeted at those industries and occupations identified to have a high prevalence of workplace noise exposure and those industries with the highest proportion of noise-exposed workers who reported non-use of HPDs.

Ethnic, racial, and gender variations in health among farm operators in the United States

PURPOSE

The purpose of this study was to collect baseline prevalence data on the health problems faced by minority, white, and female farm operators.

METHODS

An occupational health survey of farm operators was conducted by the U.S. Department of Agriculture, National Agricultural Statistics Service between February and August 2000. A stratified random sample of farm operators from 50 U.S. states based on the 1997 Census of Agriculture was selected for telephone interview. Interviews were primarily conducted using a computer assisted telephone instrument system.

RESULTS

Population prevalences were calculated for 7137 farm operators. Prevalences were greatest for musculoskeletal discomfort, followed by respiratory problems, hearing loss, and hypertension. Generally, Latino and Asian American operators had lower prevalences for health problems than white non-Latino and white operators, respectively. African-American operators had greater prevalences for hypertension, and osteoarthritis, but lower prevalences for hearing loss, skin problems, heart problems, and cancer than white operators. American Indian or Alaska Native operators had higher prevalences for musculoskeletal problems, skin problems, and hypertension.

CONCLUSIONS

Prevalences for the different ethnicity and race groups are not the same. Studies that combine racial and ethnic groups, or study only white and non-Latino farm operators may overestimate or underestimate the prevalence of health conditions in the entire farm operator population.

Hearing difficulty attributable to employment by industry and occupation: an analysis of the National Health Interview Survey--United States, 1997 to 2003

OBJECTIVE

To estimate the national burden of hearing difficulty among workers in US industries and occupations.

METHODS

Data on 130,102 employed National Health Interview Survey respondents between the ages of 18 to 65 years who were interviewed between 1997 and 2003 were analyzed to estimate the population prevalence, adjusted prevalence ratios, and fractions of hearing difficulty attributable to employment.

RESULTS

The estimated population prevalence of hearing difficulty was 11.4% (24% attributable to employment). The adjusted prevalence ratios of hearing difficulty were highest for railroads, mining, and primary metal manufacturing industry. Occupations with increased risk of hearing difficulty were mechanics/repairers, machine operators, and transportation equipment operators.

CONCLUSIONS

Hearing difficulty was differentially distributed across various industries. In industries with high rates, employers and workers should take preventive action to reduce the risk of occupational hearing loss.

Occupationally-acquired noise-induced hearing loss: a senseless workplace hazard

OBJECTIVES

Occupational noise-induced hearing loss (ONIHL) describes an acquired hearing deficiency directly attributable to excessive workplace noise exposure. Data suggest that excessive noise attributes to approximately 37% of all adult causes of hearing loss and remains a significant contributor to employment-related morbidity internationally. Typically insidiously-acquired, often without frank progressive symptomatology, regional medical agencies continue to struggle with this potentially debilitating condition. The aim of the study was to provide a synopsis of the current understanding of ONIHL, its impact on individual workers and the wider international community, and to identify barriers to more uniform adoption of personal hearing protection.

MATERIALS AND METHODS

A review of the contemporary literature was performed using defined keyword searches and OVID, PubMed, and Google Scholar as primary electronic search engines.

RESULTS

A number of published works were identified, describing aspects of the relationship between workplace-related noise exposure and subsequent development of employee hearing impairment, which demonstrate an overwhelming gender imbalance, with up to 97% of affected individuals being male. Industry-specific associations (e.g., mining, manufacturing and heavy construction) were well documented, as were links to toxin-specific exposures, in the recognized development of hearing loss. However, evidence of integration of appraisal of the topically-current area of genetic susceptibility was often lacking. Much discordance still exists among international agencies in the prescriptive regulation and enforcement of "safe" exposure limits.

CONCLUSIONS

Despite a high level of public awareness regarding the importance of hearing preservation and increasingly stringent international occupational health, safety and welfare requirements mandating provision of safer work environments, ONIHL continues to be a significant occupational hazard. ONIHL is permanent and may cause significant disability, for which there currently exists no cure, but is largely overtly-preventable. The impact of ONIHL on the global transition toward dominant communication-rich white-collar employment roles is difficult to quantitate, but is likely to be substantive upon the afflicted individual. In the mainstream setting, exposure-avoidance strategies aimed to reduce the incidence of ONIHL remain the focus of public health and occupational medicine approaches.

Hazardous decibels: hearing health of firefighters

Noise-induced hearing loss ranks among the most significant occupational health problems. In the United States, more than 1 million firefighters are at risk for noise-induced hearing loss due to exposure to hazardous levels of intermittent noise from sirens, air horns, and engines of emergency vehicles and fire trucks. Although irreversible, noise-induced hearing loss is entirely preventable through both engineering controls and personal protective equipment. This article describes occupational noise exposure, hearing loss, and strategies to prevent noise-induced hearing loss among firefighters.

Hearing loss in migrant agricultural workers

BACKGROUND

Farmers have high rates of hearing loss, yet little is known about the hearing status of migrant agricultural workers. We performed a cross-sectional survey to assess the prevalence and impact of hearing loss in this population.

METHODS

One hundred fifty migrant and seasonal agricultural workers were surveyed at a series of health fairs held at migrant camps. A bilingual questionnaire included items related to hearing loss risk factors and subjective hearing difficulties. Pure tone audiometry and tympanometry were performed in a mobile testing van.

RESULTS

More than half the subjects had some degree of hearing loss at audiometric frequencies between 500 and 6,000 Hz, especially in the higher frequencies. Hispanic males in the sample had significantly greater prevalence of high-frequency hearing loss compared to adults in the national Hispanic Health and Nutrition Examination Survey (HHANES). More than 35% of respondents complained of subjective difficulty hearing or understanding speech, yet no workers reported use of hearing aids. Even after adjusting for measured hearing loss, Hispanic farm workers were more likely than their English- speaking counterparts to complain of difficulty hearing or understanding speech, suggesting that language barriers could worsen the impact of hearing loss. Risk factors for hearing loss included age and abnormal tympanometry. Occupational exposures to noise from tractors and other machinery as well as pesticides were frequently reported, while use of hearing protection was rare.

CONCLUSION

Hearing loss is a significant and under-recognized problem in the migrant worker population. Further preventive and treatment efforts are warranted.

A Comparison of Self-Reported Hearing and Pure Tone Threshold Average in the Iowa Farm Family Health and Hazard Survey

BACKGROUND

Self-reported hearing measures are useful for surveying hearing loss in a population because they are short, and easy to administer by either questionnaire or telephone. This study aims to assess the performance of several self-reported hearing measures to identify hearing loss in a group of Iowa farmers.

METHODS

The study subjects were 98 male farmers who participated in the Iowa Farm Family Health and Hazard Survey. We tested three self-reported hearing measures; the hearing screening questions, the Rating Scale for Each Ear (RSEE), and the Health, Education and Welfare-Expanded Hearing Ability Scale (HEW-EHAS), which were originally developed and implemented in the National Health Interview Survey. The sensitivity and specificity of the self-reported hearing measures were assessed by comparing them with pure tone threshold averages. These sensitivity and specificity measures were compared between younger and older age groups.

RESULTS

The sensitivities of the screening questions, RSEE, and HEW-EHAS were 73.0%, 66.7%, and 53.3%, respectively. The specificities of the self-reported hearing measures were similar, which ranged from 81.4% to 84.8%. The sensitivities of the self-reported hearing measures were higher in the younger age group while the specificities were higher in the older age group.

CONCLUSIONS

The results of this study support the use of simple screening questions in identifying hearing loss among farmers.

Hearing loss among operating engineers in American construction industry

OBJECTIVE

Occupational noise exposure and noise-induced hearing loss (NIHL) among construction workers has long been recognized as a problem in the United States, yet little is known about the prevalence of NIHL among American construction workers. The purpose of this study was to determine the prevalence and characteristics of hearing loss among operating engineers (OEs) who operate heavy construction machinery.

METHOD

As a part of hearing protection intervention, an audiometric test was conducted for both ears at frequencies 0.5 through 8 kHz in the soundproof booth. Prior to the audiometric test, a paper-pencil pre-hearing test questionnaire was administered and an otoscopic examination was completed. Prevalence of hearing loss was determined based on hearing threshold levels (HTLs) in the worst ear with a low fence of 25 dB.

RESULT

A total of 623 workers were included in the analysis and they were predominantly middle-aged Caucasian males (mean age = 43 years, Caucasian = 90%, male = 92%). Over 60% of OEs showed hearing loss in the noise-sensitive higher frequencies of 4 and 6 kHz. The rate of hearing loss was particularly higher among workers who reported longer years of working in the construction industry. Workers showed significantly poorer hearing in the left ear, and a typical characteristic of NIHL, a V-notch at 4 or 6 kHz, was not shown in this population. Thirty-eight percent reported ringing/buzzing in the ear and 62% indicated having problems in understanding what people say in loud noise. Average reported use of hearing protection devices (HPDs) was 48% of the time they were required to be used. Significant inverse relationship was found between higher frequency (4-6 kHz) hearing loss and use of HPDs (r =-0.134, p < 0.001). Workers using HPDs more had significantly better hearing than those who did not.

CONCLUSION

The study demonstrated a significant NIHL problem and low use of HPDs in OEs. An effective hearing conservation program, including a periodic audiometric testing and hearing protection intervention, for this study population should be in place.