Marit Skogstad

Cross shift changes in lung function among bar and restaurant workers before and after implementation of a smoking ban

Objective: To study possible cross shift effects of environmental tobacco smoke (ETS) on pulmonary function among bar and restaurant employees before and after the implementation of a smoking ban in Norway. Methods: The study included 93 subjects employed in 13 different establishments in Oslo. They were examined at the beginning and end of a workshift both while ETS exposure was present and when smoking was banned. The mean exposure level of nicotine and total dust before the ban was 28 μg/m3 (range 3–65) and 275 μg/m3 (range 81–506), respectively. Following the smoking ban, the mean level of nicotine and total dust was 0.6 μg/m3 and 77 μg/m3, respectively. Assessment of lung function included dynamic lung volumes and flows. Results: The cross shift reduction in forced vital capacity (FVC) among 69 subjects participating in both examinations changed from 81 ml (SD 136) during exposure to ETS to 52 ml (SD 156) (p = 0.24) following the smoking ban. The reduction in forced expired volume in one second (FEV1) during a workshift, was borderline significantly reduced when comparing the situation before and after the intervention, by 89 ml (SD = 132) compared to 46 ml (SD = 152) (p = 0.09), respectively. The reduction in forced mid-expiratory flow rate (FEF25–75%) changed significantly from 199 ml/s (SD = 372) to 64 ml/s (SD = 307) (p = 0.01). Among 26 non-smokers and 11 asthmatics, the reduction in FEV1 and FEF25–75% was significantly larger during ETS exposure compared to after the smoking ban. There was an association between the dust concentration and decrease in FEF25–75% before the ban among non-smokers (p = 0.048). Conclusions: This first study of cross shift changes before and after the implementation of a smoking ban in restaurants and bars shows a larger cross shift decrease in lung function before compared with after the implementation of the ban.

Work-related post-traumatic stress disorder

BACKGROUND Work-related post-traumatic stress disorder (PTSD) is an important condition encountered by many occupational health practitioners. AIMS To carry out an in-depth review of the research on occupational groups that are at particular risk of developing work-related PTSD. METHODS A literature search was conducted in the databases OVID MEDLINE, OVID Embase, Ovid PsycINFO, ISI Web of Science and CSA Health and Safety Science Abstracts. RESULTS Professionals such as police officers, firefighters and ambulance personnel often experience incidents that satisfy the stressor criterion for the PTSD diagnosis. Other professional groups such as health care professionals, train drivers, divers, journalists, sailors and employees in bank, post offices or in stores may also be subjected to work-related traumatic events. Work-related PTSD usually diminishes with time. CONCLUSIONS Mental health problems prior to the traumatic event and weak social support increase the risk of PTSD. Prevention of work-related PTSD includes a sound organizational and psychosocial work environment, systematic training of employees, social support from colleagues and managers and a proper follow-up of employees after a critical event.

Exposure to thoracic dust, airway symptoms and lung function in cement production workers

Cement dust exposure has previously been associated with airway symptoms and ventilatory impairment. The aim of the present study was to examine lung function and airway symptoms among employees in different jobs and at different levels of exposure to thoracic dust in the cement production industry. At the start of a 4-yr prospective cohort study in 2007, exposure to cement dust, symptoms and lung function were recorded cross-sectionally in 4,265 employees in 24 European cement plants. Bronchial exposure was assessed by 2,670 full-shift dust samples with cyclones collecting the thoracic aerosol fraction. A job exposure matrix was constructed by grouping dust concentrations according to job type and plant. Elevated odds ratios for symptoms and airflow limitation (range 1.2–2.6 in the highest quartile), but not for chronic bronchitis, were found in the higher quartiles of exposure compared with the lowest quartile. Forced expiratory volume in 1 s (FEV1) showed an exposure–response relationship with a 270-mL deficit of FEV1 (95% CI 190–300 mL) in the highest compared with the lowest exposure level. The results support the hypothesis that exposure to dust in cement production may lead to respiratory symptoms and airway obstruction.

Lung function over six years among professional divers

Aims: To analyse longitudinal changes in pulmonary function in professional divers and their relation with cumulative diving exposure. Methods: The study included 87 men at the start of their education as professional divers. At follow up one, three, and six years later, 83, 81, and 77 divers were reexamined. The median number of compressed air dives in the 77 divers over the follow up period was 196 (range 37–2000). A group of non-smoking policemen (n = 64) were subjected to follow up examinations in parallel with the divers. Assessment of lung function included dynamic lung volumes, maximal expiratory flow rates, and transfer factor for carbon monoxide (TlCO). The individual rates of change of the lung function variables were calculated by fitting linear regression lines to the data, expressed as percent change per year. Results: The annual reductions in forced vital capacity (FVC) and forced expired volume in one second (FEV1) were 0.91 (SD 1.22) and 0.84 (SD 1.28) per cent per year in divers, which were significantly higher than the reductions in the policemen of 0.24 (SD 1.04) and 0.16 (SD 1.07) per cent per year (p < 0.001). The annual reduction in the maximal expiratory flow rates at 25% and 75% of FVC expired (FEF25% and FEF75%) were related to the log10 transformed cumulative number of dives in a multiple regression analysis (p < 0.05). The annual reductions in TlCO were 1.33 (SD 1.85) and 0.43 (SD 1.53) per cent per year in divers and policemen (p < 0.05). Conclusions: FVC, FEV1, maximal expiratory flow rates, and TlCO were significantly reduced in divers over the follow up period when compared with policemen. The contrasts within and between groups suggest that diving has contributed to the reduction in lung function.

Lung function over the first 3 years of a professional diving career

OBJECTIVES To characterise diving exposure and pulmonary function in professional divers at the start of their formal education and during the first 3 years of their professional career. METHODS The study included 87 men at the start of their education as professional divers. At follow up 1 and 3 years after the school 83 and 81 divers respectively were re-examined. Assessment of lung function included dynamic lung volumes and flows and transfer factor for carbon monoxide (TlCO). RESULTS 69 Divers had preschool SCUBA diving experience and had a median number of 70 dives (range 2–3000) to a median maximal depth of 40 (range 10–73) metres. During the 15 week introductory diving course, they had 44 dives (range 38–50) in the depth range 10–50 metres. The median number of dives over the follow up period was 95 (range 0–722) to a maximal median depth of 38 (range 0–98) metres. At the start of the diving course there were no differences in forced vital capacity (FVC), forced expired volume in 1 second (FEV1), and in TlCO between the 69 pre-exposed divers and the 18 never exposed divers. The FVC was significantly larger than predicted in both groups. At follow up at 3 years there was a significant reduction in mean (SD) FEV1 of 1.8% (6.5), in forced mid-expiratory flow rate (FEF25–75%) of 6.5% (11.7) and in forced expiratory flow at 75% of FVC expired (FEF75%) of 10.4% (16.8). There was no change in FVC. The TlCO was significantly decreased by 4.6% (8.8). No significant effects were found of cumulative diving exposure, including the number of dives, on the relative changes of any of the lung function variables. CONCLUSIONS The results indicate that divers initially belong to a selected group with large FVC. Exposure to diving may contribute to changes in pulmonary function, mostly affecting small airways conductance.

A cross-shift study of lung function, exhaled nitric oxide and inflammatory markers in blood in Norwegian cement production workers

Objectives To study possible effects of aerosol exposure on lung function, fractional exhaled nitric oxide (FeNO) and inflammatory markers in blood from Norwegian cement production workers across one work shift (0 to 8 h) and again 32 h after the non-exposed baseline registration. Methods 95 workers from two cement plants in Norway were included. Assessment of lung function included spirometry and gas diffusion pre- and post-shift (0 and 8 h). FeNO concentrations were measured and blood samples collected at 0, 8 and 32 h. Blood analysis included cell counts of leucocytes and mediators of inflammation. Results The median respirable aerosol level was 0.3 mg/m3 (range 0.02–6.2 mg/m3). FEV1, FEF25–75% and DLCO decreased by 37 ml (p=0.04), 170 ml/s (p<0.001) and 0.17 mmol/min/kPa (p=0.02), respectively, across the shift. A 2 ppm reduction in FeNO between 0 and 32 h was detected (p=0.01). The number of leucocytes increased by 0.6×109 cells/l (p<0.001) across the shift, while fibrinogen levels increased by 0.02 g/l (p<0.001) from 0 to 32 h. TNF-α level increased and IL-10 decreased across the shift. Baseline levels of fibrinogen were associated with the highest level of respirable dust, and increased by 0.39 g/l (95% CI 0.06 to 0.72). Conclusions We observed small cross-shift changes in lung function and inflammatory markers among cement production workers, indicating that inflammatory effects may occur at exposure levels well below 1 mg/m3. However, because the associations between these acute changes and personal exposure measurements were weak and as the long-term consequences are unknown, these findings should be tested in a follow-up study.

Circulating lipopolysaccharides in the blood from “bioprotein” production workers

Background: Workers producing bacterial single-cell protein (BSCP), “bioprotein,” are exposed to organic dust containing high levels of endoxins (lipopolysaccharides, LPS). Workers in this industry have complained of episodes of fever, fatigue, chest tightness, skin dryness and rubor. The aim of the present study was to quantify LPS and inflammatory mediators in plasma among the workers and non-exposed control subjects. Methods: We included eight non-smoking production workers, aged 32–51 (median 38), and eight non-smoking, non-exposed controls, aged 30–51 (median 39). Airborne and plasma endotoxin concentrations were measured, as well as plasma hsCRP and different cytokines, chemokines and metalloproteinases. Results: The workers who did not use personal respiratory protection were exposed to varying airborne levels of endotoxin, 430 (75–15 000) EU/m3 (median, range). The level of plasma LPS was significantly elevated (p = 0.01) among the workers compared to the non-exposed controls. The workers also had elevated levels of MCP-1 (p = 0.02), MIP-1α (p = 0.05) and MMP-3 (p = 0.04). IL-6 and hsCRP were also elevated among the exposed group, but not significantly (p = 0.10 and p = 0.07, respectively). Conclusions: In this study, we detected LPS in plasma of individuals exposed to high levels of LPS at their workplace. This finding is supported by elevated levels of several inflammatory cytokines among the workers, significantly exceeding that of the non-exposed control group. To the best of our knowledge, this is the first time that plasma LPS, together with increased inflammatory markers in plasma, has been detected in an occupational setting.

Auditory function among young occupational divers: a 3-year follow-up study

Auditory function was measured in a 3-year follow-up study of 54 young occupational divers divided into high-exposure ( n = 23) and low-exposure ( n = 31) groups. The divers performed open-sea dives with a median number of 132 dives (range 44-766) during follow-up. At the start of follow-up, hearing in the high-exposure group was reduced compared with that in the low-exposure group. During the follow-up period, the total group experienced a significantly reduced hearing ability at 4 kHz in the left ear. No difference in change between the last and the first measurement for both ears combined was found when the two groups were compared. A regression analysis of measurements at the end of follow-up shows an association between the loss of hearing in the left ear at 6 and 8 kHz and the total number of years of diving. This indicates that diving may contribute to hearing impairment.

Systematic review of the cardiovascular effects of occupational noise

BACKGROUND Cross-sectional studies of occupational noise and cardiovascular effects show an association between noise and hypertension but for coronary heart disease or other cardiovascular diseases (CVDs) the evidence is not convincing. AIMS To assess possible associations between occupational noise exposure and the risk for cardiovascular effects in follow-up studies published after 1999. METHODS We performed a systematic critical literature review of original articles from key literature databases of associations between workplace noise and health. The studies were identified by search in Ovid Medline, Ovid Embase, Web of Science, Scopus and ProQuest Health and Safety Sciences Abstracts. We selected prospective studies of adequate quality with a measure of association between occupational noise exposure and cardiovascular health for the meta-analysis. RESULTS Twelve papers, all prospective and mostly with high quality but with methodological shortcomings in exposure assessment, were included in the review and meta-analysis. Exposure to noise at work was consistently positively associated with hypertension [Hazard ratio (HR) = 1.68; 95% confidence interval (CI) 1.10-2.57] and CVD [relative risk (RR) = 1.34; 95% CI 1.15-1.56]. In addition, we found a trivial effect of noise exposure on CVD mortality (HR = 1.12; 95% CI 1.02-1.24). CONCLUSIONS Occupational noise exposure is strongly associated with hypertension. For other cardiovascular effects, this meta-analysis suggests a weak association, but the evidence is limited. More longitudinal studies on the effects of occupational noise on the cardiovascular system are warranted.

Lung function and respiratory symptoms in male Palestinian farmers.

ABSTRACT In a cross-sectional study of 250 farmers aged 22 to 77 years, of whom 36.4% are smokers, the authors aimed at describing lung function and respiratory symptoms and to estimate associations with exposures to pesticides and dust. Lung function was measured using a spirometer. Respiratory symptoms and exposure levels were self-reported based on a modified standardized questionnaire. Mean forced vital capacity (FVC) was 4.20 L (SD = 0.93 L), 95.51% of predicted as compared to European standards. Mean forced expiratory volume in one second (FEV1) was 3.28 L (SD = 0.80 L), 91.05% of predicted. The authors found high symptom prevalences: 14.0% for chronic cough; 26.4% for wheeze; and 55.2% for breathlessness. There was no clear association between exposure to pesticides or dust and lung function or between such exposures and respiratory symptoms. However, a significant association was found between smoking and respiratory symptoms such as chronic cough, cough with phlegm, and wheezes. The lack of farm exposure associations could be due to improvement in farmers’ awareness to pesticides hazards as well as regulations of pesticide import, or because of inherent problems with the experimental design. Farmers who kept animals and poultry seem to have less respiratory symptoms and better lung function.