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Background: Urban air pollution can trigger asthma exacerbations, but the effects of long-term exposure to traffic-related air pollution on lung function or onset of airway disease and allergic sensitisation in children is less clear., Methods: All 2107 children aged 9-14 years from 40 schools in Rome in 2000-1 were included in a cross-sectional survey. Respiratory symptoms were assessed on 1760 children by parental questionnaires (response rate 83.5%). Allergic sensitisation was measured by skin prick tests and lung function was measured by spirometry on 1359 children (77.2%). Three indicators of traffic-related air pollution exposure were assessed: self-reported heavy traffic outside the child's home; the measured distance between the child's home and busy roads; and the residential nitrogen dioxide (NO2) levels estimated by a land use regression model (R2 = 0.69)., Results: There was a strong association between estimated NO2 exposure per 10 microg/m3 and lung function, especially expiratory flows, in linear regression models adjusted for age, gender, height and weight: -0.62% (95% CI -1.05 to -0.19) for forced expiratory volume in 1 s as a percentage of forced vital capacity, -62 ml/s (95% CI -102 to -21) for forced expiratory flow between 25% and 75% of forced vital capacity and -85 ml/s (95% CI -135 to -35) for peak expiratory flow. The other two exposure indicators showed similar but weaker associations. The associations appeared stronger in girls, older children, in children of high socioeconomic status and in those exposed to parental smoking. Although lifetime asthma was not an effect modifier, there was a suggestion of a larger effect on lung function in subjects with a positive prick test. Multiple logistic regression models did not suggest a consistent association between traffic-related air pollution exposure and prevalence of respiratory symptoms or allergic sensitisation., Conclusion: The results of this study suggest that residential traffic-related air pollution exposure is associated with reduced expiratory flows in schoolchildren.

Objective: To evaluate the association of different indices of traffic-related air pollution (self-report of traffic intensity, distance from busy roads from geographical information system (GIS), area-based emissions of particulate matter (PM), and estimated concentrations of nitrogen dioxide (NO(2)) from a land-use regression model) with respiratory health in adults., Methods: A sample of 9488 25-59-year-old Rome residents completed a self-administered questionnaire on respiratory health and various risk factors, including education, occupation, housing conditions, smoking, and traffic intensity in their area of residence. The study used GIS to calculate the distance between their home address and the closest high-traffic road. For each subject, PM emissions in the area of residence as well as estimated NO2 concentrations as assessed by a land-use regression model (R(2) value = 0.69), were available. Generalised estimating equations (GEE) were used to analyse the association between air pollution measures and prevalence of "ever" chronic bronchitis, asthma, and rhinitis taking into account the effects of age, gender, education, smoking habits, socioeconomic position, and the correlation of variables for members of the same family., Results: Three hundred and ninety seven subjects (4% of the study population) reported chronic bronchitis, 472 (5%) asthma, and 1227 (13%) rhinitis. Fifteen per cent of subjects reported living in high traffic areas, 11% lived within 50 m of a high traffic road, and 28% in areas with estimated NO2 greater than 50 microg/m(3). Prevalence of asthma was associated only with self-reported traffic intensity whereas no association was found for the other more objective indices. Rhinitis, on the other hand, was strongly associated with all traffic-related indicators (eg, OR = 1.13, 95% CI: 1.04 to 1.22 for 10 microg/m(3) NO2, especially among non-smokers., Conclusions: Indices of exposure to traffic-related air pollution are consistently associated with an increased risk of rhinitis in adults, especially among non-smokers. The results for asthma are weak, possibly due to ascertainment problems.

Adverse health effects of particulate matter <10 microm in aerodynamic diameter (PM(10)) and high temperatures are well known, but the extent of their interaction on mortality is less clear. This paper describes effect modification of temperature in the PM(10)-mortality association and tests the hypothesis that higher PM(10) effects in summer are due to enhanced exposure to particles. All deaths of residents of nine Italian cities between 1997 and 2004 were selected. The case-crossover approach was adopted to estimate the effect of PM(10) on mortality by season and temperature level. Three strata of temperature corresponding to low, medium, and high "ventilation" were identified, and the interaction between PM(10) and temperature within each stratum was examined. Season and temperature levels strongly modified the PM(10)-mortality association: for a 10-microg/m(3) variation in PM(10), a 2.54% increase in risk of death in summer (95% confidence interval: 1.31, 3.78) compared with 0.20% (95% confidence interval: -0.08, 0.49) in winter. Analysis of the interaction between PM(10) and temperature within temperature strata resulted in positive but, in most cases, nonstatistically significant coefficients. The authors found much higher PM(10) effects on mortality during warmer days. The hypothesis that such an effect is attributable to enhanced exposure to particles in summer could not be rejected.

Most of the evidence regarding the association between particulate air pollution and emergency room visits or hospital admissions for respiratory conditions and asthma comes from the USA. European time-series analyses have suggested that gaseous air pollutants are important determinants of acute hospitalization for respiratory conditions, at least as important as particulate mass. The association between daily mean levels of suspended particles and gaseous pollutants (sulphur dioxide, nitrogen dioxide, carbon monoxide, ozone) was examined. The daily emergency hospital admissions for respiratory conditions in the metropolitan area of Rome during 1995-1997 were also recorded. Daily counts of hospital admissions for total respiratory conditions (43 admissions day(-1)), acute respiratory infections including pneumonia (18 day(-1)), chronic obstructive pulmonary disease (COPD) (13 day(-1)), and asthma (4.5 day(-1)) among residents of all ages and among children (0-14 yrs) were analysed. The generalized additive models included spline smooth functions of the day of study, mean temperature, mean humidity, influenza epidemics, and indicator variables for day of the week and holidays. Total respiratory admissions were significantly associated with same-day level of NO2 (2.5% increase per interquartile range (IQR) change, 22.3 microg x m(-3)) and CO (2.8% increase per IQR, 1.5 mg x m(-3)). No effect was found for particulate matter and SO2, whereas O3 was associated with admissions only among children (lag 1, 5.5% increase per IQR, 23.9 microg x m3). The effect of NO2 was stronger on acute respiratory infections (lag 0, 4.0% increase) and on asthma among children (lag 1, 10.7% increase). The admissions for all ages for asthma and COPD were associated only with same-day level of CO (5.5% and 4.3% increase, respectively). Multipollutant models confirmed the role of CO on all respiratory admissions, including asthma and COPD, and that of NO2 on acute respiratory infections. Among children, O3 remained a strong indicator of acute respiratory infections. Carbon monoxide and photochemical pollutants (nitrogen dioxide, ozone) appear to be determinants of acute respiratory conditions in Rome. Since carbon monoxide and nitrogen dioxide are good indicators of combustion products from traffic related sources, the detected effect may be due to unmeasured fine and ultrafine particles.

Two time-series studies, aimed at evaluating the acute health effect of air pollution among Rome inhabitants, were carried out. In the first study the correlation between daily mortality (1992 to 1995) and daily concentrations of five air pollutants (particles, SO2, NO2, CO, O3) was analyzed. In the second study the association between daily levels of the same pollutants and hospital admissions for respiratory and cardiovascular disease (1995-97) was evaluated. Poisson regression models were used to estimate the association between pollutant levels and health effect variables; the models included smooth functions of day of study, mean temperature, mean humidity and indicator variables for day of the week and holidays. Daily total mortality was associated with particle average concentration on that day and with NO2 levels of one or two days before. Hospital admissions for cardiovascular disease were positively correlated to particles, SO2, NO2, e CO. Hospital admissions for respiratory disease were associated with NO2 and CO levels of the same day and of two days before among children (0-14 years) and among adults (15-64 years). Increments of ozone were associated with increments of total respiratory and of acute respiratory diseases in children (0-14 years).

Objectives: To assess the relation between several daily indicators of air pollution (particulates and gases) and daily mortality in the metropolitan area of Rome and in the central part of the city., Methods: Time series analysis. The associations between daily concentrations of pollutants (particles, SO2, NO2, CO, O3) recorded by five fixed monitors and daily total mortality in the period from January 1992 to June 1995 were evaluated. The analysis included examination of the pollution effect on mortality by place of residence within the metropolitan area, by season, age, place of death (in and out a hospital), and cause of death (cardiovascular and respiratory disease). The Poisson model included loses smooth functions of the day of study, mean temperature, mean humidity, and indicator variables for day of the week and holidays., Results: The mean daily number of deaths was 56.9 (44.8 among people > or = 65 years old). A mean of 36.3 deaths occurred in the city centre; 37.3 deaths a day were recorded in a hospital. Total mortality was significantly associated with a 10 micrograms/m3 increase in particles (0.4%) on that day (log 0), and with a 10 micrograms/m3 increase in NO2 at lag 1 (0.3%) and lag 2 (0.4%) (1 and 2 days before, respectively). The effect of particles (lag 0) and of NO2 (lag 2) on total mortality was higher among those living in the city centre (0.7% and 0.5%, respectively). The risk estimates were higher in the warmer season (1.0% and 1.1%, respectively), whereas no difference was found for those dying in or out of the hospital. The effect of particles was robust to a sensitivity analysis and to the inclusion of NO2 in the regression model., Conclusions: Increase in particulates and NO2, generated by the same mobile combustion sources, is associated with a short term increase in mortality in Rome. The effect is more evident among residents in the city centre, where the levels of exposure to pollutants recorded by fixed monitors are probably more reliable indicators of personal exposure.

Objective: In the area of Malagrotta, a suburb of Rome (Italy), a large waste disposal site, a waste incinerator plant, and an oil refinery plant became operational in the early 1960s and have represented three major sources of air pollution. To evaluate the potential health risk due to airborne contamination around these point sources, a small area analysis of mortality was conducted. Cancer of the liver, larynx, lung, kidney, lymphatic, and haematopoietic systems were evaluated., Methods: Sex and age specific mortality (1987-93) and population denominators (1991) were available for the census tracts of the metropolitan area of Rome. Standardised mortality ratios (SMRs) were computed separately for males and females in bands of increasing distance from the plants, up to a radius of 10 km. Stone's test for the decline in risk with distance was performed with increments in radius of 1 km; SMRs were also computed after adjusting for a four level index of socioeconomic status., Results: No overall excess or decline in risk with distance was found for liver, lung, and lymphohaematopoietic cancers in either sex. For laryngeal cancer, an increased but not significant risk was found at 0-3 km and at 3-8 km. A significant decline with distance in mortality from laryngeal cancer was found among men (p = 0.03); the trend remained after adjusting for the socioeconomic index (p = 0.06)., Conclusions: The study showed no association between proximity to the industrial sites and mortality for most of the several conditions considered. However, mortality from laryngeal cancer declined with distance from the sources of pollution. This result is interesting, as previous findings of an increased risk of laryngeal cancer near incinerators have been controversial.

A total of 3,868 urban policemen in Rome were investigated through a historical cohort study with emphasis on mortality from cardiovascular disease and cancer. Overall mortality from cardiovascular disease, respiratory conditions, digestive and genitourinary diseases, and accidents was lower than expected. An excess risk of ischemic heart disease was observed among subjects aged less than 50 years [14 deaths, standardized mortality ratio (SMR = 1.63), 95% CI = 0.89-2.73], corresponding to workers with a short duration of employment and a short latency since first employment. Overall cancer mortality was as expected and no excess was found for lung cancer (82 deaths, SMR = 1.05). Increased mortality was observed from colon cancer (16 deaths, SMR = 1.47), melanoma (four deaths, SMR = 2.34), bladder cancer (13 deaths, SMR = 1.27), renal cancer (seven deaths, SMR = 1.39), and non-Hodgkin's lymphoma (six deaths, SMR = 1.51), although none of the excesses were statistically significant. Two deaths from male breast cancer (SMR = 14.36) and three from cancer of endocrine glands were found (SMR = 3.44). Nested case-control studies were conducted to evaluate cancer mortality risk by job category. Bladder cancer was significantly increased among car drivers (OR = 4.17); for kidney cancer, an increased odds ratio (OR = 2.27) was found among motorcyclists; non-Hodgkin's lymphoma clustered among motorcyclists (OR = 5.14). In summary, excess risk for specific cancer sites (colon, male breast, and endocrine glands) might be linked to occupational exposures; professional drivers seem to be at higher risk of bladder cancer, kidney cancer, and non-Hodgkin's lymphoma.