Urban air quality and carboxyhemoglobin levels in a group of traffic policemen.

Toxicological potential of carbon monoxide (CO) on humans is well known. Nevertheless, CO is still considered as a useful marker to detect some environmental and occupational human risk factors typical of cities. The role played by traffic pollution, indoor air quality in offices and tobacco smoke on the expression of carboxyhemoglobin (COHb%) levels was investigated in a large group of traffic policemen in Torino city (North-Western Italy). At the end of the working shift, 228 policemen responded to a questionnaire, weight and height recorded, urine spot samples collected to measure cotinine as biomarker of tobacco smoke exposure, and an arterial blood sample was taken to measure COHb levels. Data of outdoor urban air-CO were collected and to each subject a "CO outdoor air measurement" was related to his/her COHb level. Considering the annual trend of air-CO pollution from 2002 to 2004, one can assume that a general improvement of air quality in Torino was evident. Taking into account the environments where policemen work (urban outdoor and indoor), and analyzing their COHb% content, the traffic-congested areas, and, in general, the outdoor urban environment were equally risky as offices. Furthermore, if compared to CO arising from traffic-congested areas or other outdoor environments, the traffic policemen in Torino city demonstrate COHb% levels largely due to smoking habits.

Effects of tobacco smoke exposure on lung growth in adolescents.

A longitudinal study on exposure to tobacco smoke among adolescents was carried out in Turin (North-Western Italy) in January-February 1992 and in January-February 1993. In 1992, 394 schoolchildren aged 14-16 years were enrolled in a study protocol which consisted in answering a standardized questionnaire, measurement of urinary cotinine and testing of lung function (flow-volume curve--[FVC] and forced expiratory volume in I sec.--[FEV1]). In 1993, 333 schoolchildren from the same group repeated the survey. By comparison to urinary cotinine, findings obtained showed a reduction of increase, from 1992 to 1993, of -0.57% (p = 0.082) for FVC, and -0.66% (p = 0.05) for FEV1. Assuming that the systematic selection bias did not seem to have occurred, findings, obtained from a multiple regression analysis, showed that active and passive exposure to tobacco smoke, as measured by urinary cotinine, had a significant effect on lung growth (as measured by FEV1) in adolescents; this effect, though small, was dose-related.

Predictors of survival in a group of patients with chronic airflow obstruction.

This article shows the results of a 10-year follow-up study conducted on a cohort of 870 patients affected by severe chronic airflow obstruction (CAO) on spirometric tests. The main aims of the study were to identify those factors associated with reduced survival in CAO patients and to evaluate the effectiveness of a care program on patients' survival. The analysis compared the survival time and causes of death between patients who showed adherence and patients who did not show adherence to the care program. The most important results can be summarized as follows: (1) CAO patients have a high mortality rate for acute respiratory failure, cor-pulmonale, and lung cancer; (2) patient's age at the time of selection to enter follow-up influences the death hazard; (3) patients who need long-term oxygen treatment (LTOT) have a higher death hazard than those who don't need it; (4) the higher is FEV1 or PaO2 value at the time of selection, the lower the death hazard; (5) patients who need, and regularly take, long-term oxygen treatment have a lower death hazard compared to those who need it, but do not take it properly; and (6) patients with a partial reversible airway obstruction (pRAO) who regularly attend the clinic for planned check-ups, have a lower death hazard compared to those who have the same characteristics, but do not show adherence to the care program. These results indicate that an organized program to treat severe CAO patients may improve their survival.

Tobacco smoke habits in a group of adolescents: responsibility of the cohabitants in the active and passive exposure.

Several studies in adults demonstrated a positive relationship between the number of cigarettes smoked and the urinary cotinine. The aim of this work was to analyze the passive and active smoking exposure of 333 sixteen-year-old students, demonstrated by their urinary cotinine, in comparison with the smoking habits of all the cohabitants. This last information was obtained from a questionnaire and urinary cotinine in mothers. The second purpose of this work was to observe whether the smoking habits of parents can promote the voluntary active exposure to tobacco smoke in children. The considered students represent a particular group of people (16 years old) having a life-style still strictly bound to the smoking habit of parents. In fact, the nonactive smokers show urinary cotinine levels described by the following means: 28.81, 39.35, 39.62, and 57.67 ng/mL. This finding demonstrates a trend of exposure from no exposure to a maximum level of passive exposure. Similar results can be observed by considering the urinary cotinine of mothers. Finally, the active smoking habit potentially acquired by the adolescents seems to be induced also by emulation of the smoking habits of fathers. This possibility is demonstrated by a light positive and statistically significative correlation with the number of cigarettes actively smoked and, consequently, with urinary cotinine.

Involuntary exposure to tobacco smoke in adolescents: urinary cotinine and environmental factors.

The relationship between environmental tobacco smoke exposure and urinary cotinine was studied in 434 14-y-old schoolchildren. To estimate the independent contribution of physiological and environmental variables to cotinine concentrations, we conducted a multiple regression analysis of log-transformed cotinine (R(2) = .21, p < .0001). Environmental tobacco smoke exposure was associated with sharing a household with members who smoked. The most profound associations were linked to (a) the smoking habits of the mother (beta = 5.135, p = .0397); (b) the combined smoking habits of the mother and other family members (beta = 8.201, p = .0020); and (c) the total number cigarettes smoked each day by family members in the household (beta = 0.217, p = .0008). Passive smoke exposure of adolescents is a preventable risk that could be reduced by improving ventilation and by increasing the living space available to each family member. Parents should avoid smoking at home in the presence of their children.

Using reference values in pulmonary ventilation studies.

The aim of this study was to examine the discriminating power of six widely used, or recently introduced, reference values in the interpretation of pulmonary ventilation (FVC and FEV1) in occupational health surveys. These six reference values were applied to a sample of 400 Italian males; 200 of the sample were foundry workers and the other 200 were workers who were not occupationally exposed to dusts; 50% of each group were smokers. The relationship between the reference values and their capacity to discriminate between the workers occupationally exposed to dusts and the workers who smoked in each group was evaluated. The results showed very significant differences among the various reference values. Generally speaking these differences may be determined by the different selection criteria of the subjects under study, or may be a result of the different characteristics of the population included in the various studies. Our conclusions show the need for a critical approach to the use of reference values, particularly during screening tests.

Chronic bronchitis in the iron and steel industry: prevalence study.

The paper reports the results of a prevalence study on functional impairment and chronic bronchitis in 733 foundry workers and in a control group of 1041 workers not exposed to the specific risks of the iron and steel industry. This study is the first part of a longitudinal study lasting 5 years within the framework of the Fourth Research Programme of the European Coal and Steel Community. Data on microclimate and particulate pollution for the various departments showed uniformly cold and damp conditions. Concentrations of pollutants were generally below the current T.L.V.'s. The subjects were subdivided into groups according to age, smoking and length of exposure. All the subjects were administered the "E.C.S.C. Questionnaire for the study of chronic bronchitis and pulmonary emphysema" and underwent a chest X-ray and spirometry to measure FVC, FEV1 and Vmax 50. The prevalence of functional impairment and chronic bronchitis was higher in the foundry workers than in the group of non-exposed workers. A statistical standardization was made of the effect of age and smoking thus accentuating the effect of exposure. The results are compared with the data obtained by other epidemiologic studies on working populations exposed to a similar risk.

Effects of vitamin C on airway responsiveness to inhaled histamine in heavy smokers.

Histamine bronchial threshold, the provocation concentration of histamine causing a 25% fall in maximal expiratory flow at 50% of forced vital capacity from the control value (PC25MEF50), was measured in seven heavy smokers and in seven sex- and age-matched nonsmokers before and one hour after ingestion, double-blind, of vitamin C (2 g) or placebo. Smokers had significantly lower baseline values of serum ascorbate, maximal expiratory flow at 50% of forced vital capacity (MEF50) and PC25MEF50: the latter was negatively related to serum ascorbate (r = -0.85; p less than 0.001). Acute treatment with vitamin C produced a significant decrease in PC25MEF50 in smokers (95% confidence limit (CL) from 4.87-3.36 to 2.91-2.01 mg.ml-1; p = 0.017), whilst it had no effect in nonsmokers. A preliminary open study on the effect of prolonged administration of vitamin C (1 g daily) was performed in smokers. One week of treatment produced a further significant decrease in PC25MEF50 (p less than 0.0001). Our results suggest that in heavy smokers histamine bronchial responsiveness may be attenuated by chronic ascorbate deficiency. In these circumstances, acute and short-term treatment with vitamin C may increase the bronchoconstrictive response to inhaled histamine.

The effects of air pollution on the respiratory health of children: a cross-sectional study.

To investigate the effects of air pollution on the respiratory health of children, a subject of some controversy, a comparative study was undertaken of 2,385 school children who lived in central urban, peripheral urban, and suburban areas. Daily monitoring of sulphur dioxide and total suspended particle concentrations in all areas showed that pollutant concentrations in central and peripheral urban areas were above commonly accepted safety levels for respiratory health, while concentrations in the suburban area were within acceptable limits. A questionnaire administered to each mother assessed environmental exposure to pollutants in the household, the occurrence of respiratory symptoms as well as lung diseases as diagnosed by a physician, and general information. Children were interviewed about smoking habits and any acute respiratory symptoms. Children also performed standard lung function tests. Results showed that children from both urban areas had lessened pulmonary function and a higher prevalence of bronchial secretion with common colds than did those from the suburban area. These differences persisted after corrections for exposure to indoor pollutants, active or passive smoking, socioeconomic status, and sex. Parental cigarette smoking was related to a fall in forced expiratory volume in 1 second and an increased incidence of acute respiratory illnesses and chronic cough in children. Although boys had higher lung volumes and lower air flow, regression analysis showed no significant influence of the interactions "sex-geographic area" and "sex-smoking" on lung function. It was concluded that air pollution has a significant effect on the respiratory health of children.

A multivariate analysis of the risk in chronic obstructive lung disease (COLD).

This study was undertaken to assess the validity of cluster analysis for stratifying patients with severe COLD into homogenous subgroups in view of further prospective studies. To this aim, physiological measurements and questionnaire data were obtained from 532 outpatients with severe COLD (e.g. a 1 sec forced expiratory volume (FEV1) below 1.5-1/sec). The model variables selected for the partition in cluster were FEV1, PaO2, response to bronchodilators and heart rate. Two subgroups of patients were identified by the analysis: cluster I with significantly greater physiological impairment than cluster II. The comparison of the prevalences of the variables outside the model between the 2 clusters showed, in fact, that cluster I had a significantly higher prevalence of subjects with heavy smoking (p less than 0.01), prolonged occupational exposure (p less than 0.05), low body weight (p less than 0.05), recent hospitalizations for respiratory troubles (p less than 0.02) and emphysema (p less than 0.01). In conclusion, cluster analysis based on few physiological variables was able to identify, among patients with severe COLD, those with poorer general conditions and higher exposure to specific risk factors, for whom a worse prognosis of life can be expected. The advantages of cluster analysis in comparison to other techniques of classification in this kind of patient is discussed.

Diagnostic value of serum bile acids and routine liver function tests in hepatobiliary diseases. Sensitivity, specificity, and predictive value.

Total serum bile acids measured by enzymatic fluorometry and routine liver function tests were determined in a large population including 97 healthy subjects, 138 patients free of hepatobiliary diseases but affected by other diseases, and 344 patients with mild or severe hepatobiliary diseases. In order to define the diagnostic value and some operational characteristics of serum bile acids, sensitivity, specificity, and several predictive value tables for increasing cutoff levels of serum bile acids were calculated by means of a computer program. Serum bile acids and aspartate aminotransferase were found to be similar in sensitivity, specificity, and predictive value. Serum aspartate aminotransferase was found to be more suitable than serum bile acids in detecting mild hepatobiliary diseases, whereas serum bile acids were more sensitive than routine liver tests in the evaluation of severe hepatobiliary diseases. In view of its ability to detect severe hepatobiliary diseases, serum bile acids test may play a decisive role in clinical practice (eg, decision to perform a liver biopsy).

Radiographic and functional changes following exposure to different types of asbestos.

Lung function parameters were examined in 200 asbestos workers. Those exposed to chrysotile alone had less severe impairment than those exposed to both chrysotile and crocidolite. Functional changes did not vary significantly with duration of exposure; however radiographic abnormalities were related to length of exposure. Our results show that, for a population with moderate exposure to asbestos, lung function tests can discriminate smokers and nonsmokers and exposure to different kinds of asbestos, whereas discrepancies among groups with different lengths of exposure are better seen with radiographic methods.