Fabiana Scotto

Emergency ambulance dispatches and apparent temperature: A time series analysis in Emilia-Romagna, Italy

INTRODUCTION Increases in mortality associated with oppressive weather have been widely investigated in several epidemiological studies. However, to properly understand the full public health significance of heat-related health effects, as well as to develop an effective surveillance system, it is also important to investigate the impact of stressful meteorological conditions on non-fatal events. The objective of our study was to evaluate the exposure-response relationship of ambulance dispatch data in association with biometeorological conditions using time series techniques similar to those used in previous studies on mortality. METHODS Daily data of emergency ambulance dispatches for people aged 35 or older in the summer periods from 2002 to 2006 were collected for the major towns in the Emilia-Romagna region. In the first stage of the analysis, the city-specific relationship between daily ambulance dispatches and increasing apparent temperature was explored using Generalized Additive Models while controlling for air pollution, seasonality, long-term trend, holidays and weekends. The relationship between ambulance dispatches and apparent temperature was approximated by linear splines. The effects of high temperatures on health were evaluated for respiratory and cardiovascular diseases as well as for all non-traumatic conditions. In the second stage of the analysis, city-specific effects were combined in fixed or random effect meta-analyses. RESULTS The percent change in the ambulance dispatches associated with every 1 °C increase in the mean apparent temperature between 25 and 30 °C was 1.45% (95% confidence interval: 0.95, 1.95) for non-traumatic diseases and 2.74% (95% CI: 1.34, 4.14) for respiratory diseases. The percent increase in risk was greater on days in which the mean apparent temperature exceeded 30 °C (8.85%, 95% CI: 7.12, 10.58 for non-traumatic diseases). In this interval of biometeorological conditions, cardiovascular diseases became positively associated with the apparent temperature. The risks increased with age. The increase in risk for the non-traumatic diseases reached 13.34% for people aged 75 or older compared to 4.75% for those aged 35-64. CONCLUSION Time series analysis techniques were adopted for the first time to investigate emergency ambulance dispatches to evaluate the risks associated with biometeorological discomfort. Our findings show a strong relationship between biometeorological conditions and ambulance dispatches.

Urban Air Pollution Monitoring and Correlation Properties between Fixed-Site Stations

Abstract The rich regional air-monitoring network of the Emilia-Romagna region of Italy has been used to quantify the spatial variability of the main pollutants within urban environments and to analyze the correlations between stations. The spatial variability of the concentrations of the majority of pollutants within the city was very high, making it difficult to differentiate and characterize the urban environments and to apply legal limits with uniform criteria. On the other hand, the correlations between the fixed-site monitoring stations were high enough for their data to be retained generally very appropriately for controlling temporal trends. Starting from the high correlation level, a procedure was proposed and tested to derive pollution levels, using short-term measurements, such as passive samplers and mobile-station data. The importance of long-term statistics in urban air pollution mapping was emphasized. Treatment of missing data in time series and quality assurance were indicated as possible fields for applications for the correlation properties.

Characteristics and major sources of carbonaceous aerosols in PM2.5 in Emilia Romagna Region (Northern Italy) from four-year observations

The concentrations of organic and elemental carbon in PM2.5 aerosol samples were measured in two sites of Emilia Romagna (Po Valley, Northern Italy) in eight campaigns during different seasons from 2011 to 2014. Strong seasonality was observed with the highest OC concentrations during the cold periods (≈ 5.5 μg m(-3)) and the lowest in the warm months (≈ 2.7 μg m(-3)) as well as with higher EC levels in fall/winter (≈ 1.4 μg m(-3)) in comparison with spring/summer (≈ 0.6 μg m(-3)). Concerning spatial variability, there were no statistically significant difference (p<0.05) between OC concentrations at the two sampling sites in each campaign, while the EC values were nearly twofold higher levels at the urban site than those at the rural one. Specific molecular markers were investigated to attempt the basic apportionment of OC by discriminating between the main emission sources of primary OC, such as fossil fuels burning - including traffic vehicle emission - residential wood burning, and bio-aerosol released from plants and microorganisms, and the atmospheric photo-oxidation processes generating OCsec. The investigated markers were low-molecular-weight carboxylic acids - to describe the contribution of secondary organic aerosol - anhydrosugars - to quantify primary emissions from biomass burning - bio-sugars - to qualitatively estimate biogenic sources - and Polycyclic Aromatic Hydrocarbons - to differentiate among different combustion emissions. Using the levoglucosan tracer method, contribution of wood smoke to atmospheric OC concentration was computed. Wood burning accounts for 33% of OC in fall/winter and for 3% in spring/summer. A clear seasonal trend is also observed for the impact of secondary processes with higher contribution in the warm seasons (≈ 63%) in comparison with that in colder months (≈ 33%), that is consistent with enhanced solar radiation in spring/summer.

Preliminary Results Of The Project “Supersito” Concerning The Atmospheric Aerosol Composition In Emilia-Romagna Region, Italy: PM Source Apportionment And Aerosol Size Distribution

The Emilia-Romagna region and its Agency for Prevention and Environment are running a project – called Supersito – the purpose of which is to gain further knowledge about the components of fine and ultrafine particles in the atmosphere. Supersito began the measurements at the end of 2011, in this paper we summarize the preliminary results observed for the aerosol size distribution and source apportionment of PM2.5 in Bologna’s urban background. Results show that nitrates, sulphates and ammonium accounts for more than 40% of the mass of PM2.5 in the cold season and for about 30% in the summer. The carbonaceous fraction (organic aerosol plus elemental carbon) is about 40% in both seasons. PMF analysis of the data coming from the results of the mass composition shows that important fractions of PM2.5 during the cold season come from

A direct approach to control short term population dynamics in time series studies

Background: Short term population dynamics is an important issue in several epidemiological studies. Usually, calendar time or dummy variables are used to control indirectly for this confounding. This study tested a direct method. Methods: The study compared as proxy variables of population dynamics the summer 2003 data of cooking gas consumptions, solid urban waste production, and television access for the municipality of Bologna (Italy). Results: Solid urban waste production and television access data showed similar trends. Considerably different were the >65 year olds estimates with respect to total population based on television access. Conclusions: Television access data are probably the best indicator in the estimates of population dynamics in large or densely populated areas, especially because of the possibility of stratifications with respect to age.

Higher health effects of ambient particles during the warm season: The role of infiltration factors

A large number of studies have shown much higher health effects of particulate matter (PM) during the warm compared to the cold season. In this paper we present the results of an experimental study carried out in an unoccupied test apartment with the aim of understanding the reasons behind the seasonal variations of the health effects due to ambient PM2.5 exposure. Measurements included indoor and outdoor PM2.5 mass and chemical composition as well as particle size distribution of ultrafine particles. Monitoring campaigns were carried out during summer and winter following a ventilation protocol developed to replicate typical occupant behaviour according to a questionnaire-based survey. Our findings showed that seasonal variation of the relationship between ambient and indoor mass concentrations cannot entirely explain the apparent difference in PM toxicity between seasons and size distribution and chemical composition of particles were identified as other possible causes of changes in the apparent PM toxicity. A marked decrease of ultrafine particles (<100 nm) passing from outdoors to indoors was observed during winter; this resulted in higher indoor exposure to nanoparticles (<50 nm) during summer. With regards to the chemical composition, a pooled analysis showed infiltration factors of chemical species similar to that obtained for PM2.5 mass with values increasing from 0.73 during winter to 0.90 during summer and few deviations from the pooled estimates. In particular, significantly lower infiltration factors and sink effect were found for nitrates and ammonium during winter. In addition, a marked increase in the contribution of indoor and outdoor sulfates to the total mass was observed during summer.