Sexual Function in F-111 Maintenance Workers: The Study of Health Outcomes in Aircraft Maintenance Personnel

Characteristics and occupational risk assessment of occupational silica-dust and noise exposure in ferrous metal foundries in Ningbo, China

Introduction

To investigate the major existing occupational hazards and to assess the occupational health risks for ferrous metal foundries (FMFs) in Ningbo, China.

Methods

Unified questionnaires were formulated to investigate the information on the basic situations, occupational hazards, and occupational health management for 193 FMFs in Ningbo. Furthermore, we used the semi-quantitative risk assessment model, which was developed by the International Council on Mining and Metals (ICMM), to assess occupational health risks for 59 of 193 the FMFs.

Results

The casting process of FMFs in Ningbo was mainly divided into sand casting and investment casting, and silica-dust and noise were the major occupational hazards in both sand casting and investment casting foundries. Silica-dust mainly occurred in industries with such work as sand handling, modeling, falling sand, and sand cleaning, with the median of the permissible concentration-time weighted average (PC-TWA) was 0.80, 1.15, 3.52, 0.83 mg/m³, respectively. The noise mainly existed in industries with such work as sand handling, core making, falling sand, sand cleaning, cutting and grinding, and smelting with median of PC-TWA was 81.72 dB(A), 82.93 dB(A), 90.75 dB(A), 80.18 dB(A), 90.05 dB(A), 82.70 dB(A), respectively. In addition, the results of the ICMM assessment model indicated that 100 and 98.7% of the jobs exposed to silica-dust and noise in 59 FMFs have an "intolerable risk" level of risks of causing pneumoconiosis and noise deaf, respectively.

Discussion

The hazard risk of silica-dust and noise is serious for FMFs in Ningbo. It is necessary to supervise enterprises to improve operating environmental conditions, accelerate the reduction of silica-dust and noise exposure risks, and promote the healthy and sustainable development of the foundry industry.

An observed relationship between vestibular function and auditory thresholds in aircraft-maintenance workers

OBJECTIVE

We sought to examine the vestibular function and whether an association exists between vestibular function and hearing thresholds in a group of military aircraft-maintenance workers with exposures to high levels of noise and organic solvents, relative to two different comparison groups.

METHODS

Vestibular function (using functional reach) and hearing (with pure-tone audiometry) were assessed in 601 exposed personnel, compared with two unexposed groups (500 technical trade and 391 nontrade).

RESULTS

Linear regression model showed that functional reach was slightly better for the comparison groups than the exposed group, with only one group being statistically significant, and there was a significant association between vestibular function and auditory thresholds at 500 and 1000 Hz.

CONCLUSION

This study has demonstrated a relationship between low-frequency hearing loss, vestibular dysfunction, anxiety, and depression in an occupational population.

Hearing impairment in F-111 maintenance workers: the study of health outcomes in aircraft maintenance personnel (SHOAMP) general health and medical study

BACKGROUND

We sought to examine hearing loss in a group from the Royal Australian Air Force who undertook fuel tank maintenance on F-111 aircraft, with exposure to formulations containing ototoxins, relative to two different comparison groups.

METHODS

Using pure-tone audiometry, hearing thresholds were assessed in 614 exposed personnel, 513 technical-trade comparisons (different base, same job), and 403 non-technical comparisons (same base, different job). We calculated percentage loss of hearing (PLH) and used regression models to examine whether there was an association between PLH and F-111 fuel tank maintenance, adjusting for possible confounders. In addition, the difference between the observed hearing thresholds and the expected thresholds based on an otologically normal population (ISO-7029-2003) was determined.

RESULTS

The PLH ranged from nil to 96 (median 1.5, quartiles 0.3, 5.5). A logistic regression model showed no statistically significant difference in PLH among the three exposure groups (exposed vs. non-technical controls 1.1: 95% CI 0.7, 2.0 and exposed vs. technical OR 0.9: 95% CI 0.6, 1.3). The model also highlighted a number of other risk factors for PLH including age, tinnitus, smoking, depression, and use of depression medications. However, at all eight frequencies measured, all populations had lower than expected hearing thresholds based on published ISO-7029 medians.

CONCLUSIONS

Although there was no difference in PLH between the three exposure groups, the study did reveal a high degree of hearing loss between the 3 groups and a normal population.