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.

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.

Tuberculin reactivity in adult BCG-vaccinated subjects: a cross-sectional study.

INTRODUCTION: Interpretation of the tuberculin skin test (TST) may be complicated by prior bacille Calmette-Guérin (BCG) vaccination. The skin reaction to the vaccination interferes with the management of individuals who may be infected with Mycobacterium tuberculosis. OBJECTIVE: To discriminate between TST reactions due to infection and those due to vaccination in subjects with unknown BCG status. METHODS: Among 60200 subjects tested with 5TU PPD for screening purposes, 4987 contacts of infectious TB cases (Group A), 4962 BCG-vaccinated subjects (Group B) and 5000 subjects from the general population (Group C) were sampled. The frequencies of TST cut-off diameters were calculated for the three groups using a logistic regression model. The frequency of positive subjects in each group and the sensitivity, specificity and predictive values were also computed by means of these cut-offs. RESULTS: The risk of being a contact versus BCG-vaccinated increases 2.43-fold with every mm of TST diameter. The 11 mm cut-off point seems to be the best discriminating value. CONCLUSIONS: Using the traditional 10 mm cut-off, we can consider all vaccinated subjects with a positive TST to be infected. The TST remains a valuable tool for the evaluation of household contacts and suspected cases of tuberculosis in BCG-vaccinated subjects and in populations with high vaccination coverage.

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.

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.

Effect of nifedipine on salbutamol-induced bronchodilation in partially reversible airway obstruction.

The effects of the combination of oral nifedipine (20 mg) and inhaled salbutamol (400 mcg) were studied in ten stable patients with chronic partially reversible airway obstruction in a double-blind crossover design. Specific airway conductance (SGaw), forced expiratory volume in 1 second (FEV1), heart rate and blood pressure were recorded before and 30 min after administration of nifedipine or a placebo and 30, 60, 90, 150, 210 and 270 min after salbutamol inhalation. The mean value of FEV1 30 min after nifedipine was significantly (p less than 0.05) higher than after the placebo. The increase of SGaw and FEV1 produced by salbutamol was not significantly affected by pretreatment with nifedipine at any time. Nifedipine produced a significant increase of the heart rate which persisted throughout the study, but it did not influence blood pressure. No untoward effect was noticed during the study.

Duration of oral procaterol protection from methacholine-induced bronchial obstruction.

The duration of action of procaterol, a beta-2-adrenoceptor agonist with an entirely new chemical structure, was assessed, in comparison to that of salbutamol, by inhalation of 43 inhalation units of methacholine at time intervals of 1, 3, 5, 7, and 9 hours after intake of the drugs. Procaterol and salbutamol were given in a double-blind random fashion, on different days, to 12 asthmatic children; pulmonary function tests (FVC, FEV1, MEF50, MEF25), skeletal muscle tremor, and vital signs (heart rate and blood pressure) were measured. Although there was no statistical significant difference between procaterol and salbutamol, protection of large and medium airways lasted for about five hours, while normal small airway patency was still present at seven hours. It is concluded that procaterol can be a good alternative beta-2-adrenoceptor agonist when the oral route is needed.

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.

Changes in lung function of children after an air pollution decrease.

Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1.0), forced expiratory flow between 25 and 75% of FVC (FEF25-75), and maximal expiratory flow at 50% of FVC (MEF50) were measured in 1,880 school children who lived in urban areas before and after a decrease of air pollution. A group of 162 children from a suburban area served as controls. In the first survey, FEV1.0, FEF25-75, and MEF50 of children from urban areas were significantly lower, while in the second survey they were not significantly different from those of controls. The slopes over time of FEV1.0, FEF25-75, and MEF50, adjusted for sex and anthropometric variables, were closely related to the decrease of pollutants concentration. Our results suggest that a decrease of air pollution may produce an improvement of lung function.

[The impact of immigration from high incidence countries on the epidemiology of tuberculosis]. / Impatto sull'epidemiologia della tubercolosi dell'immigrazione da paesi ad alta incidenza.

Immigration in Italy from developing countries is a recent problem and the possible consequences on public health must be taken into account. The present study reports the results of Tuberculosis control activities performed by the Dispensario di Igiene Sociale of Turin, related to this population. Up to now the available data suggest that the immigrant population (mainly from North Africa and Senegal), in spite of representing a small part of residents (approximately 33,000/1,000,000) contributes to one third of Tuberculosis cases. The consequences on Tuberculosis epidemiology in Italy and our operational experience on Tuberculosis control and prevention are discussed.

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.

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.