Trace and rare earth elements in phytoplankton from the Tyrrhenian Sea (Italy).

Plankton plays a very crucial role in bioaccumulation and transfer of metals in the marine food web and represents a suitable bioindicator of the occurrence of trace and rare earth elements in the ecosystem. Trace elements and REEs were analyzed by ICP-MS in phytoplankton samples from the northwestern Mediterranean Sea. Metal concentrations in phytoplankton were found strongly influenced by seasons and depth of collection (- 30 m, - 50 m). Principal component analysis (PCA) has shown that Al, As, Cr, Cu, Ga, and Sn concentrations were related to summer and autumn in samples collected at 30 m depth, while Fe, Mn, Ni, V, and Zn levels related strongly with summer and spring at 50 m depth. Fe, Al, and Zn were the most represented elements in all samples (mean values respectively in the ranges 4.2-8.2, 9.6-13, and 1.0-4.4 mg kg-1) according to their widespread presence in the environment and in the earth crust. Principal component analysis (PCA) performed on REEs showed that mostly all lanthanides' concentrations strongly correlate with summer and autumn seasons (- 30 m depth); the highest ∑REE concentration (75 µg kg-1) was found in winter. Phytoplankton REE normalized profile was comparable to those of other marine biota collected in the same area according to the suitability of lanthanides as geological tracers.

Distribution of rare earth elements (REEs) in the feathers of gentoo penguins (Pygoscelis papua) from different geographical locations of the Antarctic peninsula area.

Antarctica is the most remote and coldest regions of the planet, but the presence of REEs there has received little attention. This study assessed REE-contents in the feathers of adult gentoo penguins from Ardley Island, Kopaitic Island and Base O'Higgins. Field work was accomplished during 2011 (austral summer), and determination of elements was performed with ICP-MS. In general, REE-levels showed descending relations as follows: Ce > La > Y > Nd > Sc > Pr > Gd > Sm > Dy >Er > Yb > Eu > Ho > Tb > Tm > Lu. The data showed an increase of the levels of REEs from the lower part of the feather to the tip. This finding seems to be spatially dependent, but geochemical, anthropogenic conditions, feeding habits, sex, or even health status of birds should also be considered. It is a subject that requires deeper attention in future studies.

Passive surveillance of wild fauna in northwestern Italy: a possible cognitive approach through geographical district study and fur elementary analysis.

The analysis of animal hair is a useful and non-invasive investigation method for monitoring metal content, whose beginning dates to a few decades ago. This study addresses the issue of wildlife mortality in Piedmont and Aosta Valley by linking the evidence to the characteristics of the territories and to hair elemental profile. The considered animal species were badger, fox, marten, and wolf. The quantitative data for 11 trace metals and 16 lanthanides were evaluated considering animal location and death causes regarding impacts, whose relevant number was confined to the Turin province and to the badger and fox species. The evaluation of the analytical results was performed after the out of bounds sample identification by mean of statistics. For trace metals, some areas have thus been identified, mainly in Turin province, in which the large excess of As, Cd, and Pb was related to district pollution. Moreover, the lower contents of Fe, Mn, and Al in Aosta Valley badgers' hair seem influenced by the different characteristics of the subsoil, in comparison to Piedmont, and a relationship with the living environment and the habits was suggested. Regarding lanthanides, Biella province represents an area in which environmental contamination and abundance of rare-earth elements was recorded.

Burden of rare earth elements and trace elements in feathers of magellanic penguins (Spheniscus magellanicus) from the southern Chilean Patagonia.

Patagonia is one of the last pristine regions on the southern hemisphere. The impact of rare earth element (REEs) and trace elements (TEs) in this region have received little attention. The main goal was to assess REEs burden in feathers of adult magellanic penguins (Spheniscus magellanicus). Sampling was performed at Magdalena Island of the Chilean Patagonia during the austral summer of 2011. Multi-elemental determination of 16 REEs and 24 TEs was performed with ICP-MS. The levels of REEs, TEs, and stable isotopes (δ15N, δ13C, and δ34S) were measured to assess the factors that condition the avian exposure to environmental contaminants. The results showed an increase of the levels of REEs and TEs from the calamus to the feather's tip. In the whole feather, the highest levels corresponded to Ce, which exhibited more than two order of magnitude than Lu and Tm levels. Similar to other penguin species, magellanic penguins can be vectors of REEs and metals in remote regions. Stable isotopes revealed that trophic ecology may influence some of the element concentrations in feathers of magellanic penguins, an issue that requires deeper attention.

Phthalate diester occurrence in marine feed and food (Mediterranean Sea).

Organic contaminants such as diesters of phthalic acid (PAEs) can be conveyed by microplastics in aquatic environment and constitute a relevant risk to marine organisms and humans that consume them. A method was developed for the identification and quantitative detection of 6 dimethyl phthalate (DMP), di-ethyl phthalate (DEP), di-n-butyl phthalate (DNBP), butyl benzyl phthalate (BBP), di-2-ethylesyl phthalate (DHEP), and di-n-octyl phthalate (DnOP). PAEs were then quantified in mesozooplankton, mollusk bivalves, and fish from the north-western Mediterranean Sea. Among all PAEs, DEHP was found in all zooplankton samples, in 30% of fish samples, and in 10% of bivalve samples. DBP was instead recovered in only 4% of samples (plankton and fish).

LIFE Med Hiss: An innovative cohort design for public health.

The aim of MED HISS methodology was to test the effectiveness of a low-cost approach to study long-term effects of air pollution, applicable in all European countries. This approach is potentially exportable to other environmental issues where a cohort representative of the country population is needed. The cohort is derived from the National Health Interview Survey, compulsory in European countries, which has information on individual lifestyle factors. In Life Med Hiss approach, subjects recruited have been linked at individual level with health data and have been then followed-up for mortality and hospital admissions outcomes. Exposure values of air pollution (PM2.5 and NO2) have been assigned using national dispersion models, enhanced by the information derived from monitoring station with data fusion techniques, and then upscaled at municipality level (highest level of detail achievable for the Italian Survey). Results for mortality have been used to test the effectiveness of this methodology and are encouraging if compared with European ones. The advantages of this technique are summarized below: •It uses a cohort already available and compulsory in European countries•It uses air quality modelling data, available for most of the countries•It permits to implement versatile environmental surveillance systems.

Association Between Short-Term Exposure to PM2.5 and PM10 and Mortality in Susceptible Subgroups: A Multisite Case-Crossover Analysis of Individual Effect Modifiers.

We performed a multisite study to evaluate demographic and clinical conditions as potential modifiers of the particulate matter (PM)-mortality association. We selected 228,619 natural deaths of elderly persons (ages ≥65 years) that occurred in 12 Italian cities during the period 2006-2010. Individual data on causes of death, age, sex, location of death, and preexisting chronic and acute conditions from the previous 5 years' hospitalizations were collected. City-specific conditional logistic regression models were applied within the case-crossover "time-stratified" framework, followed by random-effects meta-analysis. Particulate matter less than or equal to 2.5 µm in aerodynamic diameter (PM2.5) and particulate matter less than or equal to 10 µm in aerodynamic diameter (PM10) were positively associated with natural mortality (1.05% and 0.74% increases in mortality risk for increments of 10 µg/m3 and 14.4 µg/m3, respectively), with greater effects being seen among older people, those dying out-of-hospital or during the warm season, and those affected by 2 or more chronic diseases. Limited associations were found among persons with no previous hospital admissions. Diabetes (1.98%, 95% confidence interval (CI): 0.54, 3.44) and cardiac arrhythmia (1.65%, 95% CI: 0.37, 2.95) increased risk of PM2.5-related mortality, while heart conduction disorders increased risk of mortality related to both PM2.5 (4.22%, 95% CI: 0.15, 8.46) and PM10 (4.19%, 95% CI: 0.38, 8.14). Among acute conditions, recent hospital discharge for heart failure modified the PM10-mortality association. The study found increases in natural mortality from PM exposure among people with chronic morbidity; diabetes and cardiac disorders were the main susceptibility factors.

Particulate matter and gaseous pollutants in the Mediterranean Basin: results from the MED-PARTICLES project.

Previous studies reported significant variability of air pollutants across Europe with the lowest concentrations generally found in Northern Europe and the highest in Southern European countries. Within the MED-PARTICLES project the spatial and temporal variations of long-term PM and gaseous pollutants data were investigated in traffic and urban background sites across Southern Europe. The highest PM levels were observed in Greece and Italy (Athens, Thessaloniki, Turin and Rome) while all traffic sites showed high NO2 levels, frequently exceeding the established limit value. High PM2.5/PM10 ratios were calculated indicating that fine particles comprise a large fraction of PM10, with the highest values found in the urban background sites. It seems that although in traffic sites the concentrations of both PM2.5 and PM10 are significantly higher than those registered in urban background sites, the coarse fraction PM2.5-10 is more important at the traffic sites. This fact is probably due to the high levels of resuspended road dust in sites highly affected by traffic, a phenomenon particularly relevant for Mediterranean countries. The long-term trends of air pollutants revealed a significant decrease of the concentration levels for PM, SO2 and CO while for NO2 no clear trend or slightly increasing trends were observed. This reduction could be attributed to the effectiveness of abatement measures and strategies and also to meteorological conditions and to the economic crisis that affected Southern Europe.

[Environmental indicators in EpiAir2 project: air quality data for epidemiological surveillance]. / Indicatori ambientali nello studio EpiAir2: i dati di qualità dell'aria per la sorveglianza epidemiologica.

OBJECTIVE: construction of environmental indicators of air pollution suitable for epidemiological surveillance in 25 Italian cities for EpiAir2 project (2006-2010) and presentation of the results from a 10 years of surveillance system (2001-2010) in 10 Italian cities. DESIGN: data on particulate matter (PM10 and its fine fraction PM2.5), nitrogen dioxide (NO2), and ozone (O3), measured in the 2006-2010 calendar period, were collected. Meteorological data needed to estimate unbiased measures of the effect of pollutants are: temperature, relative humidity (estimated "apparent temperature"), and barometric pressure. In continuity with the previous EpiAir project, the same criteria for the selection of monitoring stations were applied and standard methods to estimate daily environmental indicators were used. Furthermore, it was checked the adequacy of the selected data to represent the population exposure. SETTING AND PARTICIPANTS: EpiAir2 project, relative to the period 2006-2010, involves the cities of Milano, Mestre-Venezia, Torino, Bologna, Firenze, Pisa, Roma, Taranto, Cagliari, and Palermo, already included in the previous study. The city of Treviso, Trieste, Padova, Rovigo, Piacenza, Parma, Ferrara, Reggio Emilia, Modena, Genova, Rimini, Ancona, Bari, Brindisi, and Napoli are added to the previous group. RESULTS: particulate matter concentrations have decreased in most cities during the study period, while concentrations of NO2 and ozone do not show a similar clear trend. The analysis of the trend showed annual mean values of PM10 higher than 40 µg/m(3) in some areas of the Po Valley, and annual mean values of NO2 higher than 40 µg/m(3) in the cities of Trieste, Milano, Padova, Torino, Modena, Bologna, Roma, and Napoli. CONCLUSION: the enlargement of the EpiAir project to 13 other cities has highlighted critical issues related to the different geographical areas under study. Results of EpiAir2 project point out the need of a monitoring system of air pollution concentrations in both urban and industrial sites, in order to obtain reliable estimates of exposure for resident populations and to evaluate the related time trend.

Short-term associations between fine and coarse particulate matter and hospitalizations in Southern Europe: results from the MED-PARTICLES project.

BACKGROUND: Evidence on the short-term effects of fine and coarse particles on morbidity in Europe is scarce and inconsistent. OBJECTIVES: We aimed to estimate the association between daily concentrations of fine and coarse particles with hospitalizations for cardiovascular and respiratory conditions in eight Southern European cities, within the MED-PARTICLES project. METHODS: City-specific Poisson models were fitted to estimate associations of daily concentrations of particulate matter with aerodynamic diameter ≤ 2.5 µm (PM2.5), ≤ 10 µm (PM10), and their difference (PM2.5-10) with daily counts of emergency hospitalizations for cardiovascular and respiratory diseases. We derived pooled estimates from random-effects meta-analysis and evaluated the robustness of results to co-pollutant exposure adjustment and model specification. Pooled concentration-response curves were estimated using a meta-smoothing approach. RESULTS: We found significant associations between all PM fractions and cardiovascular admissions. Increases of 10 µg/m3 in PM2.5, 6.3 µg/m3 in PM2.5-10, and 14.4 µg/m3 in PM10 (lag 0-1 days) were associated with increases in cardiovascular admissions of 0.51% (95% CI: 0.12, 0.90%), 0.46% (95% CI: 0.10, 0.82%), and 0.53% (95% CI: 0.06, 1.00%), respectively. Stronger associations were estimated for respiratory hospitalizations, ranging from 1.15% (95% CI: 0.21, 2.11%) for PM10 to 1.36% (95% CI: 0.23, 2.49) for PM2.5 (lag 0-5 days). CONCLUSIONS: PM2.5 and PM2.5-10 were positively associated with cardiovascular and respiratory admissions in eight Mediterranean cities. Information on the short-term effects of different PM fractions on morbidity in Southern Europe will be useful to inform European policies on air quality standards.

Air pollution and multiple acute respiratory outcomes.

Short-term effects of air pollutants on respiratory mortality and morbidity have been consistently reported but usually studied separately. To more completely assess air pollution effects, we studied hospitalisations for respiratory diseases together with out-of-hospital respiratory deaths. A time-stratified case-crossover study was carried out in six Italian cities from 2001 to 2005. Daily particulate matter (particles with a 50% cut-off aerodynamic diameter of 10 µm (PM10)) and nitrogen dioxide (NO2) associations with hospitalisations for respiratory diseases (n = 100 690), chronic obstructive pulmonary disease (COPD) (n = 38 577), lower respiratory tract infections (LRTI) among COPD patients (n = 9886) and out-of-hospital respiratory deaths (n = 5490) were estimated for residents aged ≥35 years. For an increase of 10 µg·m(-3) in PM10, we found an immediate 0.59% (lag 0-1 days) increase in hospitalisations for respiratory diseases and a 0.67% increase for COPD; the 1.91% increase in LRTI hospitalisations lasted longer (lag 0-3 days) and the 3.95% increase in respiratory mortality lasted 6 days. Effects of NO2 were stronger and lasted longer (lag 0-5 days). Age, sex and previous ischaemic heart disease acted as effect modifiers for different outcomes. Analysing multiple rather than single respiratory events shows stronger air pollution effects. The temporal relationship between the pollutant increases and hospitalisations or mortality for respiratory diseases differs.

Particulate air pollution and hospital admissions for cardiac diseases in potentially sensitive subgroups.

BACKGROUND: Although numerous studies have provided evidence of an association between ambient air pollution and acute cardiac morbidity, little is known regarding susceptibility factors. METHODS: We conducted a time-stratified case-crossover study in 9 Italian cities between 2001 and 2005 to estimate the short-term association between airborne particles with aerodynamic diameter <10 µm (PM10) and cardiac hospital admissions, and to identify susceptible groups. We estimated associations between daily PM10 and all cardiac diseases, acute coronary syndrome, arrhythmias and conduction disorders, and heart failure for 167,895 hospitalized subjects ≥ 65 years of age. Effect modification was assessed for age, sex, and a priori-defined hospital diagnoses (mainly cardiovascular and respiratory conditions) from the previous 2 years as susceptibility factors. RESULTS: The increased risk of cardiac admissions was 1.0% (95% confidence interval [CI] = 0.7% to 1.4%) per 10 µg/m PM10 at lag 0. The effect was slightly higher for heart failure (lag 0, 1.4% [0.7% to 2.0%]) and acute coronary syndrome (lag 0-1, 1.1% [0.4% to 1.9%]) than for arrhythmias (lag 0, 1.0% [0.2% to 1.8%]). Women were at higher risk of heart failure (2.0% [1.2% to 2.8%]; test for interaction, P = 0.022), whereas men were at higher risk of arrhythmias (1.9% [0.8% to 3.0%]; test for interaction, P = 0.020). Subjects aged 75-84 years were at higher risk of admissions for coronary events (2.6% [1.5% to 3.8%]; test for interaction, P = 0.001). None of the identified chronic conditions was a clear marker of susceptibility. CONCLUSIONS: An important effect of PM10 on hospitalizations for cardiac diseases was found in Italian cities. Sex and older age were susceptibility factors.

Short-Term Effects of Nitrogen Dioxide on Mortality and Susceptibility Factors in 10 Italian Cities: The EpiAir Study.

BACKGROUND: Several studies have shown an association between nitrogen dioxide (NO2) and mortality. In Italy, the EpiAir multicentric study, "Air Pollution and Health: Epidemiological Surveillance and Primary Prevention," investigated short-term health effects of air pollution, including NO2. OBJECTIVES: To study the individual susceptibility, we evaluated the association between NO2 and cause-specific mortality, investigating individual sociodemographic features and chronic/acute medical conditions as potential effect modifiers. METHODS: We considered 276,205 natural deaths of persons > 35 years of age, resident in 10 Italian cities, and deceased between 2001 and 2005. We chose a time-stratified case-crossover analysis to evaluate the short-term effects of NO2 on natural, cardiac, cerebrovascular, and respiratory mortality. For each subject, we collected information on sociodemographic features and hospital admissions in the previous 2 years. Fixed monitors provided daily concentrations of NO2, particulate matter ≤ 10 µm in aerodynamic diameter (PM10) and ozone (O3). RESULTS: We found statistically significant associations with a 10-µg/m3 increase of NO2 for natural mortality [2.09% for lag 0-5; 95% confidence interval (CI), 0.96-3.24], for cardiac mortality (2.63% for lag 0-5; 95% CI, 1.53-3.75), and for respiratory mortality (3.48% for lag 1-5; 95% CI, 0.75-6.29). These associations were independent from those of PM10 and O3. Stronger associations were estimated for subjects with at least one hospital admission in the 2 previous years and for subjects with three or more specific chronic conditions. Some cardiovascular conditions (i.e., ischemic heart disease, pulmonary circulation impairment, heart conduction disorders, heart failure) and diabetes appeared to confer a strong susceptibility to air pollution. CONCLUSIONS: Our results suggest significant and likely independent effects of NO2 on natural, cardiac, and respiratory mortality, particularly among subjects with specific cardiovascular preexisting chronic conditions and diabetes.

Particulate matter and out-of-hospital coronary deaths in eight Italian cities.

OBJECTIVES: We evaluated the association between PM(10) concentration and out-of-hospital coronary deaths in eight Italian cities during 1997-2004. METHODS: 16 989 subjects aged >35 years who died out-of-hospital from coronary causes were studied and hospital admissions in the previous 2 years identified. We studied the effect of the mean of current and previous day PM(10) values (lag 0-1). A city-specific case-crossover analysis was applied using a time-stratified approach considering as confounders weather, holidays, influenza epidemics, and summer decrease in population. The pooled percentage increase (95% CI) in mortality per 10 microg/m(3) increase in PM(10) was estimated. RESULTS: A statistically significant increase in out-of-hospital coronary deaths was related to a 10 microg/m(3) increase in PM(10): 1.46% (95% CI 0.50 to 2.43). Although no statistically significant effect modification by age was found, the effect was stronger among subjects aged >65 years (1.60%, 0.59 to 2.63), particularly those aged 65-74 (3.01%, 0.74 to 5.34). People in the lowest socio-economic category (3.34%, 1.28 to 5.45) had a stronger effect than those in the highest category. No clear effect modification was seen for gender, season or any specific comorbidity. An indication of negative effect modification was seen for previous admission for cardiac dysrhythmias. Subjects without hospital admissions in the previous 2 years were slightly more affected by PM(10) effects (1.91%, 0.28 to 3.47) than those with at least one previous hospital admission (1.44%, 0.09 to 2.82). CONCLUSIONS: Our results show that short term exposure to PM(10) is associated with coronary mortality especially among the elderly and socio-economically disadvantaged. No clear effect modification by previous hospitalisations was detected except for cardiac dysrhythmias, possibly due to protective treatment.

Respiratory symptoms in children living near busy roads and their relationship to vehicular traffic: results of an Italian multicenter study (SIDRIA 2).

BACKGROUND: Epidemiological studies have provided evidence that exposure to vehicular traffic increases the prevalence of respiratory symptoms and may exacerbate pre-existing asthma in children. Self-reported exposure to road traffic has been questioned as a reliable measurement of exposure to air pollutants. The aim of this study was to investigate whether there were specific effects of cars and trucks traffic on current asthma symptoms (i.e. wheezing) and cough or phlegm, and to examine the validity of self-reported traffic exposure. METHODS: The survey was conducted in 2002 in 12 centers in Northern, Center and Southern Italy, different in size, climate, latitude and level of urbanization. Standardized questionnaires filled in by parents were used to collect information on health outcomes and exposure to traffic among 33,632 6-7 and 13-14 years old children and adolescents. Three questions on traffic exposure were asked: the traffic in the zone of residence, the frequency of truck and of car traffic in the street of residence. The presence of a possible response bias for the self-reported traffic was evaluated using external validation (comparison with measurements of traffic flow in the city of Turin) and internal validations (matching by census block, in the cities of Turin, Milan and Rome). RESULTS: Overall traffic density was weakly associated with asthma symptoms but there was a stronger association with cough or phlegm (high traffic density OR = 1.24; 95% CI: 1.04, 1.49). Car and truck traffic were independently associated with cough or phlegm. The results of the external validation did not support the existence of a reporting bias for the observed associations, for all the self-reported traffic indicators examined. The internal validations showed that the observed association between traffic density in the zone of residence and respiratory symptoms did not appear to be explained by an over reporting of traffic by parents of symptomatic subjects. CONCLUSION: Children living in zones with intense traffic are at higher risk for respiratory effects. Since population characteristics are specific, the results of validation of studies on self-reported traffic exposure can not be generalized.

An experience of data quality evaluation in pollen monitoring activities.

In this work we report the results of some quality control tests performed on laboratory procedures referring to aerobiological monitoring activities between 2005 and 2007. In every test, the results of each operator have been compared with the scores of a group of experts. For quality evaluation, we have used accuracy and precision to define the percentage error for identification of taxa and counts of pollen grains. Cohen's K has been estimated for the analysis of reliability. This work suggests a method to set up an intercalibration test for airborne pollen monitoring and to introduce the suitableness of measurement quality objectives (MQOs). The results show the important role of operators' training and the need for standards in pollen monitoring quality evaluation.

[Environmental indicators in ten Italian cities (2001-2005): the air quality data for epidemiological surveillance]. / Indicatori ambientali in dieci città italiane (2001-2005): i dati di qualità dell'aria per la sorveglianza epidemiologica.

OBJECTIVE: to produce environmental indicators suitable for an epidemiological surveillance in 10 Italian cities part of the EpiAir Project (2001-2005). METHODS: the environmental parameters that correlate to relevant health effects are the particles with diameters less than or equal to 10 micrometers (PM10), the nitrogen dioxide (NO2) and the ozone (O3). The necessary meteorological data are: temperature, relative humidity, barometric pressure and apparent temperature.We have identified some criteria to select monitoring stations and have taken standard methods of calculation to produce environmental indicators starting from the daily data available after closely evaluating the completeness of the existing data. Furthermore, we have checked the homogeneity of the selected data to ensure that it represents the population's exposure. RESULTS: close examination of descriptive statistics shows a critical situation of the considered pollutants. The analysis of the yearly state underlines for PM10 values higher than 40 microg/m3 in the area of Mestre-Venice and in Milan, Turin, Bologna e Taranto. For NO2, values are consistently above 40 microg/m3 in Milan, Turin, Bologna, Florence, Rome and Palermo. For ozone, the concentrations were stable, with the exception of Summer 2003 when we recorded, on average, an increase of 13% compared to the mean value estimated for the ten cities during the study period, especially in Mestre-Venice, Turin and Palermo. CONCLUSIONS: it is important to ensure the consistency of the methods and instruments in environmental monitoring. To evaluate health effects and perform interventions over the longterm, it is therefore fundamental that the data be homogenous, especially during the periodic reorganizations and rationalizations of air quality management. It is also necessary to include daily meteorological data that influence pollutant dispersion and population health status.

[Air pollution and mortality in ten Italian cities. Results of the EpiAir Project]. / Inquinamento atmosferico e mortalità in dieci città italiane. Risultati del Progetto EpiAir.

OBJECTIVE: the relationship between air pollution and mortality has been well established in national and international scientific literature. This study reports the results of the EpiAir Project relative to the effect of air pollution on mortality in 10 Italian cities during 2001-2005. The association between particulate matter (PM10) and gases (nitrogen dioxide, NO2, and ozone, O3), and all natural mortality, as well as cardiac, cerebrovascular and respiratory mortality, is presented. Specific issues have been investigated, such as the latency of the air pollution-mortality effects and the identification of individual demographic characteristics and clinical conditions that result in greater susceptibility to the effects of particulate matter. METHODS: the study population consisted of 276,205 subjects aged 35+ years old, resident in one of the 10 Italian cities studied, which died in the city between 2001-2005. For each subject, information was collected on cause of death, location of death, demographical variables and hospital discharge diagnoses in the previous 2-year period. The statistical analysis was adjusted for the relevant temporal and meteorological factors using the case-crossover approach. The results for ozone are limited to the warm semester (April through September). An analysis of the association between air pollution and mortality was conducted for each city, and the city-specific estimates were meta-analyzed on a second level to obtain a pooled result, and reported inter-city heterogeneity. RESULTS: a short-term effect of PM10 on mortality has been detected for all the groups of causes considered, with latencies ranging from lag 0 for cerebrovascular mortality to lag 0-3 for respiratory mortality. The association between NO2 and mortality displays strong and similar effects for all death causes, with prolonged effects (lag 0-5) for all groups of causes. The results for O3 are similar to those found for NO2, with prolonged latency (lag 0-5) for all causes of death with the exception of cerebrovascular mortality, for which a delayed effect (lag 3-5) was identified. Individual susceptibility factors of the PM10-natural mortality association include age, as elderly subjects are especially vulnerable to the effects of particles. CONCLUSIONS: the main results of the study suggest that the air pollution originated by vehicular traffic is the most relevant environmental problem in Italian cities from a public health viewpoint.