Mortality from occupational exposure to relatively pure chrysotile: a 39-year study.

BACKGROUND: Asbestos exposure is related to serious adverse health effects. However, there is disagreement about the relationship between chrysotile exposure and mesothelioma or lung cancer. OBJECTIVES: Our aim was to investigate the mortality rate among workers exposed to relatively pure chrysotile in an asbestos cement factory. PATIENTS AND METHODS: In an asbestos cement plant opened in 1968, we prospectively studied all 317 workers. A quantity of 2,000 tons of chrysotile, with minimal amphibole contamination, was used annually until 1 January 2005. Asbestos fiber concentration was measured regularly. Date and cause of death were recorded among active and retired workers. RESULTS: Asbestos fiber concentration was always below permissible levels. Fifty-two workers died during the study. The cause was cancer in 28 subjects; lung cancer was diagnosed in 16 of them. No case of mesothelioma was reported. Death was attributed to cardiovascular diseases in 23 subjects and to liver cirrhosis in 1. Overall mortality rate was significantly lower than that of the Greek general population, standardized mortality ratio (SMR) was 0.71 (95% CI 0.53-0.93). Mortality due to cancer was increased (SMR 1.15, 95% CI 0.77-1.67), mainly due to lung cancer mortality (SMR 1.71, 95% CI 0.98-2.78), but not significantly. CONCLUSIONS: Occupational exposure to relatively pure chrysotile within permissible levels was not associated with a significant increase in lung cancer or with mesothelioma. Decreased overall mortality of workers indicates a healthy worker effect, which--together with the relatively small cohort size--could have prevented small risks to be detected.

Respiratory effects in workers processing dried tobacco leaves.

OBJECTIVES: The aim of this study was to examine the pollution level of the occupational environment and to investigate the effects of occupational exposure to tobacco dust on the respiratory system of tobacco workers. No such study has previously been conducted in Greece, which is one of the main tobacco-producing countries. METHODS: A total of 1,020 seasonal and permanent tobacco workers (188 men and 832 women) were studied in a factory in Thessaloniki. The study included: 1) completion of a questionnaire (British Medical Research Council 1986), 2) spirometry and 3) rhinomanometry. At the same time, tobacco dust levels in the working environment were measured. As controls, 469 workers (87 men and 382 women) at a Thessaloniki hospital were used. Seventy six workers with nasal symptoms underwent: 1) special nasal provocation test with tobacco dust antigen, 2) skin prick tests, and 3) measurement of total IgE, specific IgE and specific IgG against tobacco protein. RESULTS: Very high levels of total suspended dust were found in work site air (45.3-54.4 mg/m3). The prevalence of chronic bronchitis was 8.7 % versus 20.6 % in controls. Chronic obstructive pulmonary disease was found in 13 workers (1.3 %) and in 16 controls (3.4 %). FEV1 %pred, FVC %pred and the FEV1/FVC ratio were lower in controls, whereas FEF25-75 % %pred was lower in workers. There were no workers with bronchial asthma or extrinsic allergic alveolitis. Rhinitis was reported by 27.3 % of the workers versus 17.9 % of controls, whereas nasal flows were 563+/-211 versus 645 +/- 321 ml/sec, respectively. According to the results of skin prick tests, six workers were sensitized to dried tobacco leaf dust. CONCLUSIONS: The results of our study do not support an association between the development of chronic diseases of the lower respiratory system and pollutants associated with the processing of dried tobacco leaves. In contrast, an association between disorders of the upper airways and tobacco dust in work sites is postulated.

Respiratory effects in workers processing dried tobacco leaves

Objectives: The aim of this study was to examine the pollution level of the occupational environment and to investigate the effects of occupational exposure to tobacco dust on the respiratory system of tobacco workers. No such study has previously been conducted in Greece, which is one of the main tobacco-producing countries. Methods: A total of 1,020 seasonal and permanent tobacco workers (188 men and 832 women) were studied in a factory in Thessaloniki. The study included: 1) completion of a questionnaire (British Medical Research Council 1986), 2) spirometry and 3) rhinomanometry. At the same time, tobacco dust levels in the working environment were measured. As controls, 469 workers (87 men and 382 women) at a Thessaloniki hospital were used. Seventy six workers with nasal symptoms underwent: 1) special nasal provocation test with tobacco dust antigen, 2) skin prick tests, and 3) measurement of total IgE, specific IgE and specific IgG against tobacco protein. Results: Very high levels of total suspended dust were found in work site air (45.3-54.4 mg/m3). The prevalence of chronic bronchitis was 8.7 % versus 20.6 % in controls. Chronic obstructive pulmonary disease was found in 13 workers (1.3 %) and in 16 controls (3.4 %). FEV1 %pred, FVC %pred and the FEV1/FVC ratio were lower in controls, whereas FEF25-75 % %pred was lower in workers. There were no workers with bronchial asthma or extrinsic allergic alveolitis. Rhinitis was reported by 27.3 % of the workers versus 17.9 % of controls, whereas nasal flows were 563±211 versus 645 ± 321 ml/sec, respectively. According to the results of skin prick tests, six workers were sensitized to dried tobacco leaf dust. Conclusions: The results of our study do not support an association between the development of chronic diseases of the lower respiratory system and pollutants associated with the processing of dried tobacco leaves. In contrast, an association between disorders of the upper airways and tobacco dust in work sites is postulated (AU)

Objetivos: El propósito del estudio era examinar el nivel de contaminación del entorno de trabajo e investigar los efectos de la exposición laboral al polvo de tabaco sobre el aparato respiratorio de los trabajadores de la industria tabacalera. Fue el primer estudio de estas características realizado en Grecia, uno de los principales países productores de tabaco. Métodos: Se estudiaron los casos de 1.020 trabajadores temporales y permanentes de la industria tabacalera (188 hombres y 832 mujeres) en una fábrica de Tesalónica. El estudio consistió en los siguientes pasos: 1) cumplimentar un cuestionario (Consejo Bri- tánico de Investigaciones Médicas, 1986); 2) espirometría, y 3) rinomanometría. Al mismo tiempo, se midieron los niveles de polvo de tabaco en el entorno de trabajo. Se emplearon como controles 469 trabajadores (87 hombres y 382 mujeres) del hospital de Tesalónica. Se sometieron 76 trabajadores con síntomas nasales a los siguientes procedimientos: 1) prueba de provocación nasal especial con polvo de tabaco como antígeno; 2) pruebas cutáneas, y 3) medición de la IgE total, la IgE específica y la IgG específica contra proteína de tabaco. Resultados: En el aire del entorno de trabajo se observaron niveles muy elevados de polvo suspendido total (45,3-54,4 mg/m3). La prevalencia de la bronquitis crónica era del 8,7 por ciento, frente al 20,6 por ciento de los controles. Se observó enfermedad pulmonar obstructiva crónica (EPOC) en 13 trabajadores (1,3 por ciento) y en 16 controles (3,4 por ciento). Los valores del porcentaje predicho de FEV1y FVC, así como el cociente FEV1/FVC resultaron inferiores en los controles, mientras que el porcentaje predicho de FEF25-75 por ciento era inferior en los trabajadores. Ningún trabajador presentaba asma bronquial ni alveolitis alérgica extrínseca. Se observó rinitis en un 27,3 por ciento de los trabajadores frente al 17,9 por ciento de los controles, mientras que los flujos nasales resultaron ser de 563ñ211 frente a 645ñ321 ml/seg, respectivamente. Según las pruebas cutáneas, 6 trabajadores presentaban sensibilidad al polvo de las hojas secas de tabaco. Conclusiones: Los resultados de nuestro estudio no respaldan una relación entre el desarrollo de enfermedades crónicas del tracto respiratorio inferior y los contaminantes asociados a la manipulación de hojas secas de tabaco. En cambio, se postula una asociación entre los trastornos del tracto respiratorio superior y el polvo de tabaco de los entornos de trabajo (AU)

Pulmonary hypertension and respiratory failure in the development of right ventricular hypertrophy in patients with chronic obstructive airway disease.

The high incidence of right ventricular hypertrophy in patients with chronic obstructive pulmonary disease is a well-known fact. In clinical medicine according to our present status of thinking, severe impairment of ventilatory function and pulmonary hypertension are the two essential prerequisites for right ventricular involvement. To investigate this accepted assumption we studied 51 patients with chronic obstructive pulmonary disease, while they were in a remission period. The patients were subjected to clinical examination, chest roentgenography, spirometry, blood gas examination, electrocardiography, vectorcardiography, echocardiography, and right heart catheterization. The majority of the patients with significantly compromised ventilatory function and abnormal blood gases had right ventricular hypertrophy with elevation of the pulmonary artery pressure. Two subgroups of patients could be distinguished: One included 15 patients (29.4% of all patients) with normal pulmonary artery pressure and evidence of right ventricular hypertrophy. In this subgroup are included 10 patients (19.6% of all patients) showing mild ventilatory impairment and mild hypoxaemia. The second subgroup consisted of 5 patients (9.8% of all patients) with elevated mean pulmonary artery pressure at rest and right ventricular hypertrophy showing relatively mild ventilatory impairment and moderate hypoxaemia. Two conclusions could be drawn: (1) the pulmonary artery pressure at rest could be normal despite the evidence of right ventricular hypertrophy, and (2) a mild ventilatory impairment does not exclude an elevated pulmonary artery pressure or the development of right ventricular hypertrophy in patients with chronic obstructive pulmonary disease.

Bronchodilatory effect of inhaled versus oral salbutamol in bronchial asthma.

The bronchodilator effect of salbutamol inhalation was compared with the oral administration of the drug in 10 patients with bronchial asthma. The study consisted of treating each patient for 4 consecutive days with: (1) a combined regimen consisting of a 2-mg tablet of salbutamol and 10 puffs of salbutamol inhalation (100 micrograms in each puff) given in pairs of two puffs every 20 min (regimen 1); (2) salbutamol inhalation (regimen 2); (3) salbutamol tablet (regimen 3), and (4) placebo, tablet and inhalation (regimen 4). The bronchodilator effect was assessed measuring the forced expiratory volume in 1 s, the forced vital capacity and the peak expiratory flow rate. The bronchodilator response was significantly greater on the inhalation alone and the combined regimen than on the oral and placebo regimens. The combined regimen showed a better although not significant bronchodilatory response than the inhalation regimen. We conclude that the inhalation treatment with salbutamol is superior to the oral route of administration in treating bronchial asthma and that the oral treatment has an added effect.