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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. [ABSTRACT FROM AUTHOR]

Background: Asbestos is a known human carcinogen and is causally associated with malignant mesothelioma, lung, larynx and ovarian cancers. Methods: Cancer risk was studied among a pool of formerly asbestos‐exposed workers in Italy. Fifty‐two Italian asbestos cohorts (asbestos‐cement, rolling‐stock, shipbuilding, and other) were pooled and their mortality follow‐up was updated to 2018. Standardized mortality ratios (SMRs) were computed for major causes of death considering duration of exposure and time since first exposure (TSFE), using reference rates by region, age and calendar period. Results: The study included 63,502 subjects (57,156 men and 6346 women): 40% who were alive, 58% who died (cause known for 92%), and 2% lost to follow‐up. Mortality was increased for all causes (SMR: men = 1.04, 95% confidence interval [CI] 1.03−1.05; women = 1.15, 95% CI 1.11−1.18), all malignancies (SMR: men = 1.21, 95% CI 1.18−1.23; women = 1.29, 95% CI 1.22−1.37), pleural and peritoneal malignancies (men: SMR = 10.46, 95% CI 9.86−11.09 and 4.29, 95% CI 3.66−5.00; women: SMR = 27.13, 95% CI 23.29−31.42 and 7.51, 95% CI 5.52−9.98), lung (SMR: men = 1.28, 95% CI 1.24−1.32; women = 1.26, 95% CI 1.02−1.53), and ovarian cancer (SMR = 1.42, 95% CI 1.08−1.84). Pleural cancer mortality increased during the first 40 years of TSFE (latency), reaching a plateau thereafter. Conclusions: Analyses by time‐dependent variables showed that the risk for pleural neoplasms increased with latency and no longer increases at long TSFE, consistent with with asbestos clearance from the lungs. Peritoneal neoplasm risk increased over all observation time. [ABSTRACT FROM AUTHOR]

Background: Post-acute COVID-19 syndrome patients complain of sensory alterations, mainly positive symptoms such as paresthesia or neuropathic pain but also decreased tactile sensation. Using the Semmes-Weinstein monofilament test (SWMT), our study aims to confront recently infected SARS-CoV2 subjects with a control group. Methods: This is a cross-sectional, single-centric study. We performed the SWMT (North Coast Medical Inc.) on 30 patients with previous SARS-CoV2 infection (COVID group) and 46 controls (control group). These patients did not present comorbidities or sensory impairment and did not take any medications. The control group tested negative for SARS-CoV2 infection since the COVID-19 pandemic; the COVID group was examined for this study after the resolution of the infection. We tested the threshold of tactile sensation of the tips of the thumb, index, and little finger of each hand, one hand at a time; the dorsum and the hypothenar regions were also tested. Results: Both groups presented the perception of tactile sensation within the reference value. Despite this result, subclinical changes suggestive of the involvement in peripheral sensory nerve function have been identified in the tested sites in the COVID group compared to the control group. The overall mean target force (grams) was higher in the COVID group than in the control group: 27 (7) vs. 19 (10) mg, p < 0.001. Conclusion: Controls and the COVID group infection had normal tactile sensation thresholds. However, the COVID group presented a higher threshold than the control group, suggesting a possible subclinical perception of tactile sensation involvement of A-beta nerve fibers. [ABSTRACT FROM AUTHOR]

The cold response of the digital arteries in a cohort of vibration-exposed workers was related to measures of daily vibration exposure expressed in terms of r.m.s. acceleration magnitude normalised to an 8-hour day, and frequency was weighted according to either the frequency weighting Wh defined in ISO 5349-1:2001 (Ah(8) in ms-2 r.m.s) or the hand--arm vascular frequency weighting Wp proposed in the ISO Technical Report 18570:2017 (Ap(8) in ms-2 r.m.s.). The metric Ap(8), which assigns more weight to intermediate- and high-frequency vibrations (31.5-250 Hz), performed better for the prediction of cold-induced digital arterial hyperresponsiveness in the vibration-exposed workers than the measure Ah(8) derived from the conventional ISO frequency weighting, which gives more importance to lower-frequency vibrations (≤16 Hz). [ABSTRACT FROM AUTHOR]

Workers can be exposed daily to foot-transmitted vibration (FTV) from standing on mobile equipment or vibrating platforms and surfaces. This results in a consistent risk of developing neurological, vascular, and musculoskeletal problems. To date, there are no international standards describing procedures with which to evaluate the health risks deriving from long-term exposure to FTV. To study the applicability of hand--arm vibration (HAV) standards to the foot, the biomechanical responses of the hand and foot in terms of the frequency response function upon varying contact conditions were compared. Results evidenced similarities between the responses of the wrist and ankle, with differences in resonance for the fingers and toes. The study confirms that HAV standards are more suitable than whole-body vibration standards for evaluating higher frequency exposure to FTV. [ABSTRACT FROM AUTHOR]

Background: The frequent use of hand-held vibrating tools by construction workers exposes them to hand-transmitted vibration (HTV) and noise. This study investigated the effect of combined exposure to HTV and noise on workers' fatigues under simulated work with a typical building destruction tool. Methods:The repeated measures study was conducted on 40 construction workers exposed to HTV (5 m/s2 rms with frequencies of 31.5, 63, and 125 Hz), HTV (10 m/s2 rms-31.5 Hz), noise (90 dBA), and concurrent exposure (noise (90 dBA) + HTV (10 m/s2 rms-31.5 Hz)) with the typical vibrating hand-held tool for 30 minutes. Electromyography signals determined each worker's fatigue level in the Flexor digitorum superficialis (FDS) muscle in two pre-and post-exposure periods. The subjects also filled out the visual analog scale to evaluate mental fatigue severity subjectively. Results:The mean difference of muscle fatigue parameters was significant in all scenarios except for the two scenarios of alone exposure to HTV (5 m/s2 -125 Hz) and noise exposure (p-value < 0.05). The mean difference of mental fatigue in all scenarios except for the two scenarios of exposure to HTV (5 m/s2 -125 Hz) and exposure to HTV (5 m/s2 -63 Hz) was significant (p-value < 0.05). The most differences in muscle fatigue parameters (Amplitude = 8.16±5.63, Mean frequency=-4.69±3.78) and mental fatigue (4.97±2.38) were observed in the simultaneous exposure to noise and HTV. Conclusion: Noise exposure alone cannot produce remarkable effects on muscle fatigue but can aggravate the effects of vibrations as a consequence of synergistic interaction. However, the role of noise on perceived mental fatigue was more dominant than the HTV. These findings should be considered to adapt the existing exposure limits to actual work conditions. [ABSTRACT FROM AUTHOR]