Annals Of Work Exposures and Health最新文献

Background: In studies of occupational health, longitudinal environmental exposure, and biomonitoring data are often subject to right skewing and left censoring, in which measurements fall below the limit of detection (LOD). To address right-skewed data, it is common practice to log-transform the data and model the geometric mean, assuming a log-normal distribution. However, if the transformed data do not follow a known distribution, modeling the mean of exposure may result in bias and reduce efficiency. In addition, when examining longitudinal data, it is possible that certain covariates may vary over time.

Objective: To develop predictive quantile regression models to resolve the issues of left censoring and time-dependent covariates and to quantitatively evaluate if previous and current covariates can predict current and/or future exposure levels.

Methods: To address these gaps, we suggested incorporating different substitution approaches into quantile regression and utilizing a method for selecting a working type of time dependency for covariates.

Results: In a simulation study, we demonstrated that, under different types of time-dependent covariates, the approach of multiple random value imputation outperformed the other approaches. We also applied our methods to a carbon nanotube and nanofiber exposure study. The dependent variables are the left-censored mass of elemental carbon at both the respirable and inhalable aerosol size fractions. In this study, we identified some potential time-dependent covariates with respect to worker-level determinants and job tasks.

Conclusion: Time dependency for covariates is rarely accounted for when analyzing longitudinal environmental exposure and biomonitoring data with values less than the LOD through predictive modeling. Mistreating the time-dependency as time-independency will lead to an efficiency loss of regression parameter estimation. Therefore, we addressed time-varying covariates in longitudinal exposure and biomonitoring data with left-censored measurements and illustrated an entire conditional distribution through different quantiles.

Introduction: Respirable crystalline silica (RCS) exposures in tanzanite gem mining have been linked to tuberculosis and silicosis among miners. We conducted a plot study to assess RCS exposures and to introduce safer mining practices in one small-scale underground tanzanite mine.

Materials and methods: Personal and area air samples for RCS were collected during tanzanite mining operations before and after improved work practices employed to reduce exposures and analyzed using X-ray diffraction. Area samples were collected at the rest area, located approximately 300 m underground and 100 m from other work activities. Improved practices included the use of wet drilling methods and drilling with new bits.

Results: A total of 33 personal and 4 area air samples were collected. Pre-intervention, mean exposures for all operations, drilling operations, non-drilling activities, and area samples were 122 mg/m3, 247 mg/m3, 34.3 mg/m3, and 1.95 mg/m3, respectively which exceeded the U.S. OSHA Permissible Exposure Limit (PEL) by 2,440 times for all operations, by 4,946 times for drilling operations, by 686 times for non-drilling activities and 39 times for area samples collected at an underground rest area. The post-intervention results showed a 99% reduction of RCS exposures for wet drilling operations, 98.5% reduction for non-drilling activities, and 36% reduction for area samples. Despite improvements, post-intervention RCS exposures during drilling had a mean of 2.08 mg/m3 or more than 41 times the OSHA PEL.

Conclusions: We successfully piloted a program to work with small-scale tanzanite miners to reduce RCS exposures and raise awareness about the occupational health risks of RCS, though additional measures are recommended to further reduce RCS exposures. Similar programs should be taken to scale throughout underground mining sites in Tanzania and other countries.

Whole body vibration (WBV) is linked to short- and longer-term adverse health outcomes, including cognitive impairment, stress and memory loss, loss of balance, reduced proprioception, visual and vestibular disturbances, gastrointestinal problems, and musculoskeletal disorders. Epidemiological evidence supports the link between WBV and headache and head discomfort, but few experimental studies have examined this relationship, particularly with increased muscle tension, as an intermediary. This study aimed to investigate the relationship between muscle tension and vibration intensity, between perceived neck pain and headache/head discomfort and vibration intensity, and between muscle tension and reported neck pain and headache symptoms from simulated WBV based on field measurements of all-terrain vehicle operation on farm terrain. We observed significantly higher electromyography amplitude in the High condition (equivalent to EU Directive's Exposure Limit Value) compared to both Low (equivalent to EU Directive's Exposure Action Value) and Control (quiet sitting) conditions at the left upper trapezius muscle but there were no significant time effects. Neck pain and headache/head discomfort significantly increased after both Low (91% increase from baseline) and High (154% increase from baseline) vibration conditions but there were no significant differences between conditions. Based on simple regression modeling, the relationship between muscle activity and neck pain or headache was very weak (R2 = 0-0.093). Given the possibility of multiple factors contributing to headache symptoms, future research should not only consider the role of muscle tension but also sensory conflict, excessive noise, biodynamic responses, and a combination of these factors.

Objectives: Assessing occupational exposure to radiofrequency electromagnetic fields (RF-EMF) presents significant challenges due to the considerable variability in exposure levels within and between occupations. This spatial and temporal variability complicates the reliable evaluation of potential health risks associated with RF-EMF exposure in the workplace. Accurate assessment methods are crucial to understand the extent of exposure and to evaluate potential health risks, especially given the potential for higher exposures in occupational settings compared to the general population. This study compares the historical RF-EMF exposure estimates in the INTEROCC RF-EMF job-exposure matrix (RF-JEM) with recent personal measurement data collected in 2 countries as part of the OccRF-Health study, to assess the broader applicability of the RF-JEM.

Methods: Weighted kappa (k  w) coefficients and Spearman rank correlation tests were performed to assess the alignment between RF-JEM estimates and measurements for 8 h time-weighted average exposure intensity and prevalence estimates across various occupations. The comparisons were mainly based on 22 jobs having ≥5 measured workers in the OccRF-Health study.

Results: Poor agreement was found for both exposure prevalence and intensity between both methods (k  w < 0.1). RF-JEM values likely overestimated exposure levels for both electric (E) and magnetic (H) fields (mean percentage difference >194%) compared to current personal measurements.

Conclusions: Findings suggest that the INTEROCC-JEM likely overestimates current exposure intensity levels in the measured jobs. Adopting a semiquantitative JEM could also mitigate misclassification errors due to exposure variability, improving accuracy in exposure assessment. These findings indicate the need for more targeted personal measurements, including among highly exposed workers, and for potentially considering new exposure metrics to more accurately assess occupational RF-EMF exposures in occupational epidemiological research.

Recycling demands are increasing and new biowaste plants are established. The aim of this study is to obtain knowledge about occupational hygiene in biowaste pretreatment plants. At 6 plants, bioaerosol exposure, hand hygiene, and bioaerosol concentrations in work areas were investigated repeatedly. The total inflammatory potential (TIP) of exposures was measured using the human HL-60 cell line. Exposure to airborne bacteria, bacteria able to grow anaerobic, fungi(37°C), endotoxin, and TIP differed between plants and was lowest in a plant transporting waste in closed pipes compared to plants where waste was delivered on the receiving hall floor. Conversely, high exposures were measured in a plant that also processes compost. All microbial components had an impact on TIP of workers' exposure with main effects of fungi and endotoxin. Seasonality was found for several exposures and TIP, and they were lowest in the winter. Concentrations of bacteria and fungi on workers' hands at the end of the workday were 15 times higher for production than for nonproduction workers. In work areas, the concentrations of airborne fungi were highest in the waste-receiving area. Bacteria (3.2 µm) and anaerobic bacteria (4.0 µm) were present as larger airborne particles than fungi (2.8 µm), and bacteria were largest in the waste-receiving area. The microbial community compositions of exposures and work areas differed between plants and work areas. In conclusion, measures to reduce exposure should focus on the waste-receiving area and on the production workers. Differences in exposures and community compositions were found between seasons, work areas, work groups, and plants.

Objectives: Evidence suggests that workers exposed to psychosocial stressors at work from the effort-reward imbalance (ERI) model are at increased risk for type 2 diabetes mellitus (T2DM). However, evidence about the effect of ERI on prediabetes is scarce. This study aimed to examine the association between effort-reward imbalance at work, glycated hemoglobin level and the prevalence of prediabetes in women and men from a prospective cohort study.

Methods: This study was conducted among 1354 white-collar workers followed for an average of 18 years. Effort-reward imbalance at work was measured in 1999 to 2001 using a validated instrument. Glycated hemoglobin was assessed at follow-up (2015 to 2018). Differences in mean glycated hemoglobin levels were estimated with linear models. Prediabetes prevalence ratios (PRs) were computed using robust Poisson regression models.

Results: In women, those exposed to effort-reward imbalance at work at baseline had a higher prevalence of prediabetes (PR = 1.60, 95% confidence interval: 1.02-2.49) at follow-up following adjustment for sociodemographic, lifestyle-related, clinical, and other occupational risk factors. There was no difference in mean glycated hemoglobin levels.

Conclusion: Among women, effort-reward imbalance at work at midlife was associated with the prevalence of prediabetes, at older age. Preventive workplace interventions aiming to reduce the prevalence of effort-reward imbalance at work may be effective to reduce the prevalence of prediabetes among women.

Objectives: The aim of this systematic review was to study the association between occupational mechanical exposures and shoulder osteoarthritis (OA).

Methods: A protocol was registered in PROSPERO. Four databases were systematically searched based on PECOS criteria. Outcome was defined as shoulder OA (acromioclavicular (AC) and/or glenohumeral OA) and exposure as occupational mechanical exposures (vibration, upper arm elevation, force, lifting, repetition, and combined mechanical exposures). We included epidemiological studies estimating the prevalence of shoulder OA or the association between occupational mechanical exposures and shoulder OA. Two researchers independently screened articles, performed data extraction, and assessed the risk of bias and level of evidence using GRADE.

Results: A total of 1642 articles were screened, of which 7 met the inclusion criteria. Four studies were assessed as having a high risk of bias, 1 with a moderate risk, and 2 with a low risk. Based on job titles, higher prevalence estimates (2.9% to 61.8%) were found in exposed job groups. For all occupational mechanical exposures, exposure-response relations were found in relation to AC OA. For vibration, the odds ratio (OR) ranged between 1.7 and 3.1 in the highest exposure groups, while the ORs for upper arm-elevation, force, lifting, repetition, and combined mechanical exposures ranged between 0.5 to 2.2, 1.3 to 1.8, 7.3 to 10.3, 2.4, and 2.2 to 2.9. Low or very low level of evidence was found for all exposures.

Conclusions: This systematic review found an indication of an association between occupational mechanical exposures and shoulder OA, especially AC OA. However, the level of evidence varied between low and very low. High-quality studies assessing the association and differentiating between the specific shoulder joints are highly warranted.

Introduction: Despite world-leading measures in place to protect employees from second-hand smoke exposure in workplaces in the United Kingdom, workers who deliver health and social care in private homes remain unprotected legally in this setting from second-hand smoke exposure (SHS).

Methods: Fourteen individuals took part in either an in-depth telephone interview (n = 11) or an online focus group discussion (n = 3), including home-care workers (n = 5) and managers (n = 5) based in Lanarkshire (Scotland) and local/national policy makers (n = 4). Participants were asked about the extent to which exposure to SHS is an issue during home visits and possible additional measures that could be put in place to eliminate exposure.

Results: Participants highlighted the difficulties in balancing the provision of care in a person's own home with the right of workers to be able to breathe clean air and be protected from SHS. Current strategies to reduce staff exposure to SHS during home visits were often reported as inadequate with SHS not a hazard considered by managers beyond protecting pregnant staff or those with pre-existing respiratory conditions such as asthma. Simple respiratory protective equipment (as used during the COVID-19 pandemic) was rightly identified as being ineffective. Methods such as nicotine replacement therapy and e-cigarettes were identified as potential ways to help people who smoke achieve temporary asbstinence prior to a home visit.

Conclusion: Implementing appropriate and proportionate measures to protect home-care workers from the harms posed by SHS should be a priority to help protect the health of this often overlooked occupational group.

Objectives: A Coronavirus disease 2019 (COVID-19) workplace outbreak is a risk to the health of workers and business continuity. To minimise this risk, companies have implemented risk management measures (RMMs) designed to mitigate SARS-CoV-2 transmission within the workforce. The objective of this work was to gather insights into the application of RMMs in non-healthcare workplaces and to improve understanding of the practical barriers to their implementation.

Methods: Data were collected using a pre-designed framework from 12 volunteer workplaces through discussions with staff responsible for site safety and during site visits to observe the RMMs and work processes. To evaluate ventilation effectiveness, measurements for carbon dioxide (CO2) were taken during the site visit and logged over an extended period in selected occupied areas.

Results: RMMs that were implemented well included working at home for office and other non-production staff, provision, and use of face coverings, provision for hand hygiene, and as methods became commonly available, carrying out testing for infected people. However, maintaining adequate physical distancing in many production areas proved difficult because established factory layouts cannot be easily changed and there is often a need for workers to be close to each other to communicate. A major shortcoming identified was the understanding and application of measures to improve workplace ventilation. Rapidly installing and/or upgrading mechanical ventilation systems during a pandemic may not be practical and ideally should be considered in building design. Measuring CO2 in occupied workspaces proved to be a useful tool for identifying areas with potentially inadequate ventilation.

Conclusions: Preventing workplace attendance by identifying infected individuals is challenging, making effective RMMs crucial to mitigating virus transmission. The effectiveness of individual RMMs can be uncertain; therefore, it is necessary to adopt multilayered RMMs. Successful implementation relies on measures that are specific to individual workplaces, identified by accurate risk assessment, regularly reviewed for effectiveness, and worker compliance. Establishing suitable risk mitigation policies and providing staff supervision are vital to ensure the sustained and effective implementation of RMMs. For RMMs that require technical understanding, such as workplace ventilation systems, specialist support may be necessary to ensure effective implementation.