Sources of noise exposure across Australian workplaces: cross-sectional analysis and modelling the impact of a targeted noise-source reduction initiative.

CONTEXT: Workplace noise regulations and guidance follow the hierarchy of control model that prioritizes eliminating or reducing noise at its source. OBJECTIVES: To determine the main sources of workplace noise exposure in the Australian working population and estimate the reduction of workers exposed over the noise limit (LAeq,8h > 85 dB) if noise levels of specific tools or equipment were reduced by 10 dB. METHODS: Information on the tools used and tasks performed during each participant's last working shift was collected from 4,977 workers via telephone survey. Using a predetermined database of task-based noise levels, partial noise exposures (Pa2h) were determined for each noisy activity performed by the workers and their daily noise exposure level (LAeq,8h) was estimated. Partial exposures were categorized into 15 tool/task groups and the tally, average, and sum (Pa2h) for each group were calculated. The impacts of 5 different scenarios that simulated a reduction of 10 dB in noise emissions for specific tool groups were modelled. RESULTS: Powered tools and equipment were responsible for 59.3% of all noise exposure (Pa2h); vehicles for 10.6%; mining, refineries, and plant equipment for 5.1%; and manufacturing and food processing for 4.2%. Modelling demonstrated that a 10 dBA noise-level reduction of all powered tools and equipment would lead to a 26.4% (95% confidence interval: 22.7% to 30.3%) reduction of workers with an LAeq,8h > 85 dB. This could represent over 350,000 Australian workers no longer exposed above the workplace limit daily. CONCLUSIONS: A universal reduction of 10 dB to power tools and equipment would substantially reduce the future burden of hearing loss, tinnitus, workplace injuries, and other health effects. Initiatives to reduce the noise emissions of specific powered tool groups are warranted.

The Associations Between Workplace Noise, Ototoxic Chemicals, and Tinnitus.

OBJECTIVE: To investigate the occupational risk factors associated with tinnitus in the Australian working population. DESIGN: The research was conducted using data collected from the Australian Workplace Exposure Survey-Hearing, a national cross-sectional study of 4970 workers conducted in 2016 to 2017. Workers were asked if they experienced tinnitus and if they answered affirmatively, they were asked about the frequency and length of the presentations. Based on their answers, each worker was categorized as having no tinnitus or any tinnitus, with an additional group of workers with any tinnitus subcategorized as having constant tinnitus. Exposure assessment was conducted using an automated expert assessment method. Exposures included daily noise (L Aeq,8h ), hand-arm vibration (A(8)), impulse noise, smoking status, styrene, trichloroethylene, toluene, n-hexane, p-xylene, ethylbenzene, lead, and carbon monoxide. Univariate and multivariate logistic regression models were used to examine the associations between workplace exposures and tinnitus. RESULTS: Workers with an estimated noise exposure above the workplace limit (L Aeq,8h > 85 dBA) had 1.73 (95% confidence interval [CI]: 1.42 to 2.11) increased odds of any tinnitus and 2.15 (95% CI: 1.60 to 2.89) odds of constant tinnitus. The odds of workers having any tinnitus increased with increasing noise exposure levels in a dose-response relationship that strengthened when considering only those with constant tinnitus. In the fully adjusted model, statistically significant associations were seen for lead exposure with both any and constant tinnitus, toluene exposure with constant tinnitus, and carbon monoxide exposure with any tinnitus. CONCLUSIONS: These results suggest that, in addition to workplace noise, occupational exposures to lead, toluene, and carbon monoxide are associated with tinnitus.

The prevalence of tinnitus in the Australian working population.

OBJECTIVES: To estimate the prevalence of tinnitus in Australian working people; to identify occupational and demographic factors associated with tinnitus. DESIGN: Cross-sectional national telephone survey of self-reported frequency and duration of tinnitus. SETTING, PARTICIPANTS: Australian Workplace Exposure Survey (AWES) - Hearing; 4970 currently employed people aged 18-64 years, recruited by random digit dialling, representative by sex of the workforce population, 7 June 2016 - 20 March 2017. MAIN OUTCOME MEASURES: Prevalence of occasional, intermittent, and constant tinnitus, and of any tinnitus, by occupational group, sex, and other demographic characteristics; estimated numbers of working people with constant or any tinnitus, by occupational group and sex. RESULTS: Of 4970 respondents, 1317 reported experiencing tinnitus (26.5%): 713 people had occasional tinnitus (14.3%), 259 intermittent tinnitus (5.2%), and 345 constant tinnitus (6.9%). The sample prevalence of constant tinnitus was greater among men (7.5%; 95% CI, 6.2-8.7%) than women (3.3%; 95% CI, 2.3-4.3%), and was higher in older age groups. After rake weighting our survey responses, we estimated that 2.4 million workers (24.8%; 95% CI, 23.2-26.4%) experience tinnitus, including 529 343 with constant tinnitus (5.5%; 95% CI, 4.6-6.3%). The estimated prevalence of constant tinnitus was highest for automotive workers (16.7%; 95% CI, 9.5-23.8%), drivers (13.0%; 95% CI, 7.3-18.6%), farmers (12.1%; 95% CI, 5.9-18.4%), and workers in other trades (10.4%; 95% CI, 4.6-16.2%). CONCLUSIONS: The prevalence of tinnitus in the Australian workforce is high, particularly in certain occupations. Workplace practices and conditions that increase the risk of tinnitus should be examined, and targeted workplace prevention strategies developed.

Exposure to Hand-Arm Vibration in the Australian Workforce.

OBJECTIVE: To estimate the prevalence of hand-arm vibration (HAV) in Australian workplaces. METHODS: The Australian Workplace Exposure Survey (AWES)-Hearing was a cross-sectional telephone survey of Australian workers conducted in 2016-2017. Respondents were asked about the time spent using tools or performing tasks known to be associated with HAV during their most recent working day. We created a library of HAV magnitude levels for each tool/task and estimated each worker's daily HAV exposure level using standard formulae. We categorized each worker as to whether they exceeded the daily occupational limits of 2.5 and 5.0 m/s2. Results were extrapolated to the Australian working population using a raked weighting method. RESULTS: In our sample of 4991 workers, 5.4% of men and 0.7% of women exceeded the HAV action limit of 2.5 m/s2 on their most recent working day. We estimate that 3.8% of the Australian workforce exceeds the HAV limit of 2.5 m/s2 and 0.8% exceeds the 5 m/s2 limit. Men were more likely to exceed the HAV limits than women, as were those with trade qualifications, and those who worked in remote locations. Workers in the construction, farming, and automobile industries had the highest prevalence of HAV exposure. Tool groups that contributed to higher exposure levels included: compactors, rollers, and tampers; power hammers and jackhammers; and underground mining equipment. CONCLUSIONS: HAV is common in the Australian working population. Given the health risks associated with this exposure, reduction strategies and interventions should be developed, with engineering controls as the starting point for exposure reduction strategies.

Productivity Burden of Occupational Noise-Induced Hearing Loss in Australia: A Life Table Modelling Study.

Background: Occupational noise-induced hearing loss (ONIHL) is one of the most common yet preventable occupational diseases. The aim of this study was to estimate the economic burden of ONIHL in the Australian working population by quantifying and monetising ONIHL-related loss of Quality Adjusted Life Years (QALY) and Productivity Adjusted Life Years (PALYs). Methods: We simulated the number of moderate-to-severe ONIHL by multiplying the age-specific prevalence of occupational noise exposure by the excess risks of ONIHL. Life table modelling was applied to workers with ONIHL. The QALY and PALY weights attributable to hearing loss were sourced from published data. The 2016 Gross Domestic Product per full-time equivalent worker in Australia was used to estimate the cost of productivity loss due to ONIHL. The cost due to the loss of well-being was quantified using willingness to pay thresholds derived from an Australian longitudinal study. Results: Under current occupational noise exposure levels in Australia, we estimated that over 80,000 male workers and over 31,000 female workers would develop ONIHL over 10 years of exposure. Following this cohort until the age of 65 years, the estimated loss of QALYs and PALYs were 62,218 and 135,561 respectively, with a projected loss of AUD 5.5 billion and AUD 21.3 billion due to well-being and productivity loss, respectively. Reducing noise exposure at work would substantially reduce the economic burden of ONIHL. Conclusion: ONIHL imposes substantial burden on Australian economy. Interventions to reduce occupational noise exposure are warranted.

The estimated prevalence of exposure to carcinogens, asthmagens, and ototoxic agents among healthcare workers in Australia.

BACKGROUND: Healthcare workers are occupationally exposed to various hazardous chemicals and agents that can potentially result in long-term adverse health effects. These exposures have not been comprehensively examined at a population level. The aim of this study was to examine occupational exposures to a wide range of asthmagens, carcinogens, and ototoxic agents among healthcare workers in Australia. METHODS: Data were collected as part of the Australian Work Exposures Studies, which were computer-assisted telephone surveys conducted in 2011, 2014, and 2016 to assess the prevalence of occupational exposures to carcinogens, asthmagens, and ototoxic agents, respectively, among Australian workers. Using data on healthcare workers, the prevalence of exposures to these agents was calculated and associations of demographic variables and occupation groups with exposure status were examined. RESULTS: The prevalence of exposure to at least one asthmagen, carcinogen, and ototoxic agent was 92.3%, 50.7%, and 44.6%, respectively. The most common exposures were to (a) cleaning and sterilizing agents in the asthmagen group; (b) shift work in the carcinogen group; and (c) toluene and p-xylene among ototoxic agents. Exposure varied by occupation, with exposure to carcinogens and ototoxic agents highest among personal carers and exposure to carcinogens most likely among nursing professionals and health and welfare support workers. CONCLUSION: The results demonstrate that a substantial proportion of Australian healthcare workers are occupationally exposed to asthmagens, carcinogens, and ototoxic agents. These exposures are more common among certain occupational groups. The information provided by this study will be useful in prioritizing and implementing control strategies.

Exposure to noise and ototoxic chemicals in the Australian workforce.

OBJECTIVE: To determine the current prevalence of exposure to workplace noise and ototoxic chemicals, including co-exposures. METHOD: A cross-sectional telephone survey of nearly 5000 Australian workers was conducted using the web-based application, OccIDEAS. Participants were asked about workplace tasks they performed and predefined algorithms automatically assessed worker's likelihood of exposure to 10 known ototoxic chemicals as well as estimated their full shift noise exposure level (LAeq,8h) of their most recent working day. Results were extrapolated to represent the Australian working population using a raked weighting technique. RESULTS: In the Australian workforce, 19.5% of men and 2.8% of women exceeded the recommended full shift noise limit of 85 dBA during their last working day. Men were more likely to be exposed to noise if they were younger, had trade qualifications and did not live in a major city. Men were more likely exposed to workplace ototoxic chemicals (57.3%) than women (25.3%). Over 80% of workers who exceeded the full shift noise limit were also exposed to at least one ototoxic chemical in their workplace. CONCLUSION: The results demonstrate that exposures to hazardous noise and ototoxic chemicals are widespread in Australian workplaces and co-exposure is common. Occupational exposure occurs predominantly for men and could explain some of the discrepancies in hearing loss prevalence between genders.

A Systematic Review of Full-Shift, Noise Exposure Levels Among Construction Workers: Are We Improving?

Context: Construction industry workers are at high risk of occupational noise exposure. Although regulations and guidelines for this industry specify the use of noise controls, workers continue to be exposed to hazardous noise levels. Objectives: The objectives of this study were (i) to collate and describe full-shift noise exposure experienced by construction workers; (ii) to review trends in full-shift exposure over time and between countries; and (iii) to identify any occupational categories within the construction industries that have higher levels of exposure. Results: Of the 1171 studies found using key terms, 25 contained noise exposure measurements that met our inclusion criteria. Sample populations were predominantly from large construction sites and primarily comprised occupations known to engage in noisy workplace activities. Studies spanned over 36 years with all having average full-shift noise exposure over 85 A-weighted decibels (dBA). No time trend in full-shift noise exposure levels for construction workers was observed. Construction workers in the subgroup occupations of mason, sheet metal workers, carpenters, concrete workers, and operating engineers consistently had mean LAeq,8h over the 85 dBA limit. Conclusion: Studies spanning 36 years in 10 countries consistently show construction workers have been exposed to hazardous noise levels. There has been no significant change over time of the average full-shift exposure levels of construction workers, including in all occupational subgroups except iron-workers. Some variability in full-shift measures is due to sampling methods and population characteristics and to a lesser extent, methods used to derive exposure levels.

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.