Noise-induced hearing loss in construction workers being assessed for hand-arm vibration syndrome

Effect of noise and hand-transmitted vibration exposure on hearing and equilibrium under a simulated work environment with building tools

BACKGROUND

Construction workers are exposed to hand-transmitted vibration (HTV) and/or noise caused by vibrating hand tools in the work environment.

OBJECTIVE

The present study aims to investigate the effects of exposure to HTV and/or noise on workers' hearing loss and body balance.

METHODS

Forty construction workers were exposed to HTV (10 m/s2 rms, 31.5 Hz) and/or typical construction noise (90 dBA) in three simulated experiment scenarios with the vibrating hand-held tool for 30 minutes over three days. The hearing loss from 1000 to 6000 Hz and the body balance were determined before and after each exposure scenario.

RESULTS

Separate noise exposure at all frequencies except for 1000 Hz could significantly affect hearing threshold levels (p-value<0.05). Separate exposure to HTV cannot lead to a remarkable effect on hearing loss (p-value>0.05); however, it can synergistically increase the effect of noise on hearing loss. Also, the affected frequency range in concurrent exposure has been greater than in separate noise exposure. The separate effects of exposure to HTV and noise on the subjects' body balance were not statistically significant (p-value>0.05); however, these effects became significant in concurrent exposure (p-value<0.05). Based on the estimated effect sizes, noise could synergistically increase the observed effect of HTV on body balance.

CONCLUSION

There is a synergistic interaction between HTV and noise on hearing loss and body balance. It seems necessary to pay attention to the risk evaluation of simultaneous exposure to noise and HTV when setting the occupational action limit values.

The Combined Impact of Hand-Arm Vibration and Noise Exposure on Hearing Sensitivity of Agricultural/Forestry Workers-A Systematic Literature Review

Hand-arm vibration (HAV), which potentially causes vibration white finger (VWF), and occupational noise are serious issues in the agricultural and forestry industries. Generally, agricultural workers operate as single-family/small businesses and thus are exempted from Occupational Safety and Health Administration (OSHA) regulations/laws for noise and HAV otherwise applicable to other industries in general. The agricultural/forestry sectors are at increased risk as working hours are longer than a typical 8-h work shift putting them at greater risk of hearing loss. The study was conducted to assess the possible association between hearing sensitivity on combined exposure to noise and hand-arm vibration. A systematic literature review was conducted on exposure to noise and HAV in the agricultural/forestry sector and the resulting impacts on hearing. The peer-reviewed articles in English were searched with 14 search words in three databases of PubMed, Ergo Abstracts, and Web of Science without any filter for the year for fully available article text. The database literature search resulted in 72 articles. Forty-seven (47) articles met the search criteria based on the title. Abstracts were then reviewed for any relationship between hearing loss and hand-arm vibration/Raynaud's phenomenon/VWF. This left 18 articles. It was found that most agricultural workers and chainsaw workers are exposed to noise and VWF. Hearing is impacted by both noise and aging. The workers exposed to HAV and noise had greater hearing loss than non-exposed workers, possibly due to the additive effect on temporary threshold shift (TTS). It was found that VWF might be associated with vasospasm in the cochlea through autonomous vascular reflexes, digital arteries narrowing, vasoconstriction in the inner ear by noise, ischemic damage to the hair cells and increased oxygen demand, which significantly affects the correlation between VWF and hearing loss.

Proposal of Combined Noise and Hand-Arm Vibration Index for Occupational Exposure: Application to a Study Case in the Olive Sector

In many production and industrial sectors, workers are exposed to noise and hand-arm vibrations (HAV). European directives have established the maximum limit values or exposure action values for noise and vibration independently. However, in many cases, workers who endure hand-arm vibration also receive high noise levels. This research suggests a procedure to aid the establishment of precautionary measures for workers with simultaneous exposure to both physical agents. This procedure defines a combined index based on the energy doses for both noise and HAV. From this combined index, the suggested methodology allows a recommended exposure time for workers with simultaneous noise and HAV exposure to be calculated. This methodology can be adapted to tackle the relative importance assigned to both agents according to the safety manager and new knowledge on combined health effects. To test this method, a measurement campaign under real working conditions was conducted with workers from the olive fruit-harvesting sector, where a variety of hand-held machinery is used. The results of the study case show that the suggested procedure can obtain reliable exposure time recommendations for simultaneous noise and HAV exposures and is therefore a useful tool for establishing prevention measures.

Occupational Disease as the Bane of Workers' Lives: A Study of Its Incidence in Slovakia. Part 2

The main objective of this article is to monitor the development of the number of occupational diseases related to selected physical factors in the working environment (noise, vibration and dust). Each region of Slovakia has its own specific social and economic conditions. Due to the existence of a strong correlation between the several regional variables observed, principal component analysis (PCA) was used to determine the new variables. Cluster analysis was used to group regions with similar characteristics. A dendrogram was created using the average linkage method, which illustrated the similarity of the regions studied. The value of the cophenetic correlation coefficient (CC = 0.90) confirms the validity of the average linkage method. The result of the cluster analysis is the grouping of the eight regions into five homogenic groups (clusters). An analysis of the data shows that Slovakia’s regional differences significantly influence the incidence of occupational diseases in individual regions. It is shown that, in Slovakia, the development of the number of occupational diseases has seen a favourable trend in the long term.

Occupational Noise-Induced Hearing Loss among Migrant Workers in Kuwait

Although the effect of hearing loss on years lived with disability (YLD) is quite substantial, occupational hearing loss among migrant workers is significantly under-studied. In Kuwait, where nearly two-thirds of the population are migrant workers, the burden of occupational noise-induced hearing loss (ONIHL) is unknown. The objective of the study was to assess the prevalence of ONIHL among migrant workers in Kuwait and explore workplace and individual risk factors that are associated with ONIHL. We obtained data of annual physical exams for the year 2018 conducted by the Shuaiba Industrial Medical Center (SIMC) for all industrial workers in the area. We applied univariate and multivariate logistic regression models to estimate the effects of individual and occupational characteristics on ONIHL. A total of 3474 industrial workers visited the SIMC for an annual exam. The vast majority were men (99%) and non-Kuwaitis (98%) with a median age of 38 years. A total of 710 workers were diagnosed with ONIHL with a prevalence of 20.4%. Age, years of experience, and self-reported exposure to noise were associated with statistically significant higher odds of ONIHL. When adjusted for age, years of experience, and other individual level factors, type of industry was not a statistically significant predictor of ONIHL. The study uncovers the significant burden of hearing loss among the migrant worker subpopulation in Kuwait, an area of occupational health that is often underestimated or unrecognized. Although laws and regulations are in place to prevent and control noise in the workplace, the onus is on local authorities to ensure the necessary training and controls aimed to reduce noise exposure.

Development and Validation of a Clinical Frailty Index for the World Trade Center General Responder Cohort

Objectives: To develop and validate a clinical frailty index to characterize aging among responders to the 9/11 World Trade Center (WTC) attacks. Methods: This study was conducted on health monitoring data on a sample of 6197 responders. A clinical frailty index, WTC FI-Clinical, was developed according to the cumulative deficit model of frailty. The validity of the resulting index was assessed using all-cause mortality as an endpoint. Its association with various cohort characteristics was evaluated. Results: The sample's median age was 51 years. Thirty items were selected for inclusion in the index. It showed a strong correlation with age, as well as significant adjusted associations with mortality, 9/11 exposure severity, sex, race, pre-9/11 occupation, education, and smoking status. Discussion: The WTC FI-Clinical highlights effects of certain risk factors on aging within the 9/11 responder cohort. It will serve as a useful instrument for monitoring and tracking frailty within this cohort.

The Association Between Occupational Exposure to Hand-Arm Vibration and Hearing Loss: A Systematic Literature Review

Background

Hearing loss is one of the most prevalent worker health conditions worldwide. Although the effect of noise exposure on hearing is well researched, other workplace exposures may account for significant hearing loss. The aim of this review was to determine whether occupational hand–arm vibration exposure through use of power or pneumatic tools, independent of noise exposure, is associated with permanent hearing loss. Do workers suffer from hand–arm vibration–induced hearing loss?

Methods

Peer-reviewed articles published in English between 1981 and 2020 were identified through five online databases with five search keywords. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, including online database search methodology, study selection, article exclusion, and assessment of potential study design confounders and biases, were followed.

Results

Database searches retrieved 697 articles. Fifteen articles that reported 17 studies met the criteria for review. All but two studies revealed statistically significant associations between occupational exposure to hand–arm vibration and hearing loss. The majority of the study results revealed associations between hand–arm vibration and hearing loss, independent of potential age and noise confounders.

Conclusion

Few studies have examined the association between occupational exposure to hand–arm vibration and hearing loss. Dose response data were limited as only one study measured vibration intensity and duration. Although the majority of studies identified statistically significant associations, causal relationships could not be determined. Further research using standardized and uniform measurement protocols is needed to confirm whether the association between occupational exposure to hand–arm vibration and permanent hearing loss is causal and the mechanism(s).

Raising awareness of hand-arm vibration syndrome (HAVS) using posters

BACKGROUND

Hand-arm vibration syndrome (HAVS) is caused by prolonged occupational exposure to hand-transmitted vibration. Although HAVS is preventable, disease awareness and prevention knowledge are lacking in high-risk workplaces; this may contribute to under-diagnosis, delays in seeking care, and poor health outcomes. Posters may be used to increase awareness in the workplace.

OBJECTIVE

To conduct a pilot survey in workers with HAVS about poster use in their workplaces, their recommendations for poster campaigns and training programs, and their evaluation of HAVS awareness and prevention posters.

METHODS

All eligible HAVS patients in the Occupational Health Clinic at St. Michael's Hospital, in Toronto, Canada, were asked to complete a questionnaire on workplace poster use and to evaluate a set of HAVS posters.

RESULTS

Fifty workers participated; almost all were males, aged 50 and older, working in construction. Most indicated having non-HAVS specific awareness posters in their workplaces. There was a positive evaluation of the design, content, and potential usefulness of the posters. The poster depicting finger blanching stood out most. The poster depicting anti-vibration gloves rated highest for relatability and effectiveness at conveying disease importance.

CONCLUSIONS

Participants supported the proposed use of industry-specific HAVS awareness posters in their workplaces. Future research should evaluate the effectiveness of these posters in the workplace.

Risk of hearing loss among workers with vibration-induced white fingers

BACKGROUND

We examined the risk of hearing loss for workers who use hand-held vibrating tools with vibration-induced white fingers (VWF) compared to workers without VWF.

METHODS

Data on 184 participants from a 21-year cohort were gathered with questionnaires and measurements. The effects on hearing status of VWF, hand-arm vibration exposure, smoking habits, age and two-way interactions of these independent variables were examined with binary logistic regression. Analyses were made for the right hand and ear as well as for the hand with VWF and the ear with worse categorized hearing status.

RESULTS

Workers with VWF in their right hand had an increased risk of hearing loss (odds ratio 2.2-2.3) in the right ear. Workers with VWF in any hand did not have any increased risk of hearing loss in the ear with worse hearing status.

CONCLUSIONS

This study supports the hypothesis that VWF increases the risk of hearing loss among workers who use hand-held vibrating tools in a noisy environment.