A prospective study of decline in lung function in relation to welding emissions

<p>Abstract</p> <p>Background</p> <p>Numerous cross-sectional studies have reported reduced lung function among welders but limitations of exposure assessment and design preclude causal inference. The aim of this study was to investigate if long-term exposure to welding fume particulates accelerates the age-related decline in lung function.</p> <p>Methods</p> <p>Lung function was measured by spirometry in 1987 and 2004 among 68 steel welders and 32 non-welding production workers. The decline in forced expiratory volume (FEV₁) was analysed in relation to cumulated exposure to fume particulates among welders during the follow-up period.</p> <p>Results</p> <p>Among smokers the decline in FEV₁through follow-up period was in average 150 ml larger among welders than non-welders while the difference was negligible among non-smokers. The results did not reach statistical significance and within welders the decline in lung function was not related to the cumulated welding particulate exposure during follow-up period</p> <p>Conclusion</p> <p>Long-term exposure to welding emissions may accelerate the age-related decline of lung function but at exposure levels in the range of 1.5 to 6.5 mg/m³the average annual excess loss of FEV₁is unlikely to exceed 25 ml in smokers and 10 ml in non-smokers.</p

The influence of vessel movements on the energy expenditure of fishermen in relation to activities and occupational tasks on board

Background: Previous studies of professional fishing activities have indicated that vessel movements correlate to fishermen’s energy expenditure. We have previously demonstrated that even in calm weather, the heel and pitch significantly increase the fishermen’s energy expenditure, ignoring the activities carried out on board. This continuation of the study goes further by exploring the relation between the exposure to the ship’s movements and the fishermen’s energy expenditure during various physical activities on board. Materials and methods: Four fishermen on 2 contemporary steel trawlers recorded their work activities on an hourly basis during a 4 days fishing voyage. The energy expenditure was estimated with a body monitoring system (SenseWear Pro 3) carried as an armband, placed on the right upper arm. The vessels’ movements were assessed by a gyroscope placed in the wheelhouse. The additional energy expenditure relative to the energy expenditure during sleep was recorded during activities such as navigation, fishing, and machine handling and was correlated to the vessels’ recorded movements (pitch/roll). Data were analysed by linear regression. Results: Roll and pitch were less than 10o for both vessels during the voyages. The fishermen’s energy expenditure differed with the tasks undertaken and correlated with the vessels’ movements, but for navigation and fishing the correlation was only significant in the highest — fourth quartile of — pitch/roll. Conclusions: This study has demonstrated that vessel’s movements in calm weather increase the energy expenditure during navigation, fishing, and machine handling and that the relation differs in between these activities on board and rest.

Eye movement characteristics reflected fatigue development in both young and elderly individuals

Abstract Fatigue can develop during prolonged computer work, particularly in elderly individuals. This study investigated eye movement characteristics in relation to fatigue development. Twenty young and 18 elderly healthy adults were recruited to perform a prolonged functional computer task while their eye movements were recorded. The task lasted 40 minutes involving 240 cycles divided into 12 segments. Each cycle consisted of a sequence involving memorization of a pattern, a washout period, and replication of the pattern using a computer mouse. The participants rated their perceived fatigue after each segment. The mean values of blink duration (BD) and frequency (BF), saccade duration (SCD) and peak velocity (SPV), pupil dilation range (PDR), and fixation duration (FD) along with the task performance based on clicking speed and accuracy, were computed for each task segment. An increased subjective evaluation of fatigue suggested the development of fatigue. BD, BF, and PDR increased whereas SPV and SCD decreased over time in the young and elderly groups. Longer FD, shorter SCD, and lower task performance were observed in the elderly compared with the young group. The present findings provide a viable approach to develop a computational model based on oculometrics to track fatigue development during computer work

Can selection explain the protective effects of farming on asthma?

INTRODUCTION AND OBJECTIVE: Reduced asthma and allergy risks in farmers have been ascribed to microbial exposures. However, selection may also play a role and this was assessed in two Scandinavian farming populations. MATERIALS AND METHODS: Asthma prevalence in 739 Danish farming students was compared to that of 1,105 siblings. 8,482 Norwegian farmers were also compared with 349 early retired farmers. RESULTS: The prevalence of ever-asthma was 5.4% in farming students and 5.2% in siblings (OR 1.1; 95%CI 0.73-1.7). Current asthma in farmers was 3.0% compared to 6.3% in farmers who had retired early (OR 1.8, 95%CI 1.1-2.9). Adjustments for early retirement increased the asthma prevalence by 0.3-0.6%. Farmers who had changed production were more likely to have asthma (OR 9.8, 95% CI 6.0-16). CONCLUSIONS: No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma