Little is known about the short-term effects of ultrafine particles. We evaluated the effect of particulate matter with an aerodynamic diameter ≤10 μm (PM10), ≤2.5 μm (PM2.5), and ultrafine particles on emergency hospital admissions in Rome 2001–2005. We studied residents aged ≥35 years hospitalized for acute coronary syndrome, heart failure, lower respiratory tract infections, and chronic obstructive pulmonary disease (COPD). Information was available for factors indicating vulnerability, such as age and previous admissions for COPD. Particulate matter data were collected daily at one central fixed monitor. A case-crossover analysis was performed using a time-stratified approach. We estimated percent increases in risk per 14 μg/m3 PM10, per 10 μg/m3 PM2.5, and per 9392 particles/mL. An immediate impact (lag 0) of PM2.5 on hospitalizations for acute coronary syndrome (2.3% [95% confidence interval = 0.5% to 4.2%]) and heart failure (2.4% [0.3% to 4.5%]) was found, whereas the effect on lower respiratory tract infections (2.8% [0.5% to 5.2%]) was delayed (lag 2). Particle number concentration showed an association only with admissions for heart failure (lag 0–5; 2.4% [0.2% to 4.7%]) and COPD (lag 0; 1.6% [0.0% to 3.2%]). The effects were generally stronger in the elderly and during winter. There was no clear effect modification with previous COPD. We found sizeable acute health effects of fine and ultrafine particles. Although differential reliability in exposure assessment, in particular of ultrafine particles, precludes a firm conclusion, the study indicates that particulate matter of different sizes tends to have diverse outcomes, with dissimilar latency between exposure and health response.

Objectives: Few studies have assessed the effects of policies aimed to reduce traffic-related air pollution. The aims of this study were to evaluate the impact, in terms of air quality and health effects, of two low-emission zones established in Rome in the period 2001–2005 and to assess the impact by socioeconomic position (SEP) of the population.Methods: We evaluated the effects of the intervention on various stages in the full-chain model, that is, pressure (number and age distribution of cars), emissions, PM₁₀and NO₂concentrations, population exposure and years of life gained (YLG). The impact was evaluated according to a small-area indicator of SEP.Results: During the period 2001–2005, there was a decrease in the total number of cars (−3.8%), NO₂and PM₁₀emissions and concentrations (from 22.9 to 17.4 μg/m³for NO₂and from 7.8 to 6.2 μg/m³for PM₁₀), and in the residents' exposure. In the two low-emission zones, there was an additional decrease in air pollution concentrations (NO₂: −4.13 and −2.99 μg/m³; PM₁₀: −0.70 and −0.47 μg/m³). As a result of the policy, 264 522 residents living along busy roads gained 3.4 days per person (921 YLG per 100 000) for NO₂reduction. The gain was larger for people in the highest SEP group (1387 YLG per 100 000) than for residents in the lowest SEP group (340 YLG per 100 000).Conclusion: The traffic policy in Rome was effective in reducing traffic-related air pollution, but most of the health gains were found in well-off residents.

In this study, long-term aerosol particle total number concentration measurements in five metropolitan areas across Europe are presented. The measurements have been carried out in Augsburg, Barcelona, Helsinki, Rome, and Stockholm using the same instrument, a condensation particle counter (TSI model 3022). The results show that in all of the studied cities, the winter concentrations are higher than the summer concentrations. In Helsinki and in Stockholm, winter concentrations are higher by a factor of two and in Augsburg almost by a factor of three compared with summer months. The winter maximum of the monthly average concentrations in these cities is between 10,000 cm^-3 and 20,000 cm^-3, whereas the summer min is ˜;5000–6000 cm^-3. In Rome and in Barcelona, the winters are more polluted compared with summers by as much as a factor of 4–10. The winter maximum in both Rome and Barcelona is close to 100,000 cm^-3, whereas the summer minimum is >10,000 cm^-3. During the weekdays the maximum of the hourly average concentrations in all of the cities is detected during the morning hours between 7 and 10 a.m. The evening maxima were present in Barcelona, Rome, and Augsburg, but these were not as pronounced as the morning ones. The daily maxima in Helsinki and Stockholm are close or even lower than the daily minima in the more polluted cities. The concentrations between these two groups of cities are different with a factor of about five during the whole day. The study pointed out the influence of the selection of the measurement site and the configuration of the sampling line on the observed concentrations.

Background:A smoking ban in all indoor public places was enforced in Italy on 10 January 2005.Methods:We compared indoor air quality before and after the smoking ban by monitoring the indoor concentrations of fine (<2.5 μm diameter, PM_2.5) and ultrafine particulate matter (<0.1 μm diameter, UFP). PM_2.5and ultrafine particles were measured in 40 public places (14 bars, six fast food restaurants, eight restaurants, six game rooms, six pubs) in Rome, before and after the introduction of the law banning smoking (after 3 and 12 months). Measurements were taken using real time particle monitors (DustTRAK Mod. 8520 TSI; Ultra-fine Particles Counter-TRAK Model 8525 TSI). The PM_2.5data were scaled using a correction equation derived from a comparison with the reference method (gravimetric measurement). The study was completed by measuring urinary cotinine, and pre-law and post-law enforcement among non-smoking employees at these establishmentsResults:In the post-law period, PM_2.5decreased significantly from a mean concentration of 119.3 μg/m³to 38.2 μg/m³after 3 months (p<0.005), and then to 43.3 μg/m³a year later (p<0.01). The UFP concentrations also decreased significantly from 76 956 particles/cm³to 38 079 particles/cm³(p<0.0001) and then to 51 692 particles/cm³(p<0.01). Similarly, the concentration of urinary cotinine among non-smoking workers decreased from 17.8 ng/ml to 5.5 ng/ml (p<0.0001) and then to 3.7 ng/ml (p<0.0001).Conclusion:The application of the smoking ban led to a considerable reduction in the exposure to indoor fine and ultrafine particles in hospitality venues, confirmed by a contemporaneous reduction of urinary cotinine.