Cinzia Perrino

An atmospheric stability index based on radon progeny measurements for the evaluation of primary urban pollution

Abstract An atmospheric stability index for the evaluation of urban primary pollution, based on the elaboration of natural radioactivity data yielded by a stability monitor, has been developed. The instrument determines the atmospheric concentration of the short-lived decay products of radon, whose emanation rate can be assumed to be constant in the time and space scale of observation. The index gives information about the dilution properties of the lower boundary layer and allows to highlight the relevant role of the dilution factor in determining primary pollution events. The atmospheric stability indices have been calculated during a 1-yr study carried out in the urban area of Rome (October 1999–September 2000). On the basis of the index, every day of the period has been classified in terms of intensity of a potential primary pollution event. The comparison between this classification and the real concentration value of primary pollutants, measured in the background urban station of Rome, yielded very good results. This shows that the index constitutes a powerful and valuable tool for describing primary pollution events in urban areas and confirms that the role played by the mixing properties of the lower boundary layer is essential in determining primary pollution in urban areas.

Measurement of nitrous acid in milan, italy, by doas and diffusion denuders

Abstract Measurements of the atmospheric mixing ratio of nitrous acid have been carried out by means of the differential optical absorption system (DOAS) during a wintertime field study carried out in the urban area of Milan (Italy). Preliminary laboratory calibration of the DOAS was carried out by making use of a standard source of pure HONO which provided an interference-free UV absorption spectrum of HONG and recalculation of the absorption cross-section of this compound. Very high HONO mixing ratios, up to values exceeding 10 ppb, were measured during the campaign. DOAS results were compared with those obtained by using the annular denuder technique and good agreement was observed during the whole measurement period. On the basis of these measurements, a study on the relationship between the dynamic conditions of the lower boundary layer and the temporal trend of HONG mixing ratio can be carried out, in order to obtain indications about the sources of this species in urban atmospheres.

Evaluation of a High-Purity and High-Stability Continuous Generation System for Nitrous Acid

A flow-type system for the generation of nitrous acid in the mass flow rate range of 3.5-400 nmol/min is described. The system based on the reaction between gaseous hydrochloric acid, generated by means of a low-pressure permeation device, and solid sodium nitrite allows the continuous production of highly pure nitrous acid (purity >99.5%) and thus the generation of standard atmosphere in a very wide range of nitrous acid mixing ratio (5-20000 ppb). The system is of easy construction and exhibits a very high reproducibility and excellent long-term output stability. These features allow us to obtain any desired value of nitrous acid mass flow rate by simply tuning the temperature and flow rate values. As a consequence of the high purity of the generated compound, it was possible to obtain a clear absorption spectrum of nitrous acid without performing any correction for NO 2 interference.

Determination of soluble ions and elements in ambient air suspended particulate matter: Inter-technique comparison of XRF, IC and ICP for sample-by-sample quality control.

In this paper, we describe a validation procedure for chemical fractionation analysis of elements (Al, As, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, S, Sb, Si, Sr, Ti and V) and soluble ions (Cl(-), NO(3)(-), SO(4)(2-), Na(+), NH(4)(+), Mg(2+), Ca(2+)) in suspended particulate matter (PM). The procedure applies three distinct measurement techniques (XRF, IC and ICP-OES) to the analysis of individual samples. The techniques used generate different outputs at different stages in the procedure. This makes it possible to identify the contributions of specific parameters to measurement uncertainty. On this basis, we propose a scheme for controlling the analytical quality of data from individual samples in which inter-technique comparisons is used in the same way many analytical methods use surrogates. We apply this scheme to about 310 samples of PM(10) and PM(2.5) identifying and assessing the main factors contributing to measurement uncertainty. This procedure successfully resolved a number of difficulties frequently encountered during the analysis of PM, including lack of appropriate reference materials and the low reliability of alternative techniques of quality control. The results demonstrate the critical importance of sample treatment prior to destructive analysis by IC and ICP.

Short-term effects of particulate matter constituents on daily hospitalizations and mortality in five South-European cities: results from the MED-PARTICLES project.

BACKGROUND Few recent studies examined acute effects on health of individual chemical species in the particulate matter (PM) mixture, and most of them have been conducted in North America. Studies in Southern Europe are scarce. The aim of this study is to examine the relationship between particulate matter constituents and daily hospital admissions and mortality in five cities in Southern Europe. METHODS The study included five cities in Southern Europe, three cities in Spain: Barcelona (2003-2010), Madrid (2007-2008) and Huelva (2003-2010); and two cities in Italy: Rome (2005-2007) and Bologna (2011-2013). A case-crossover design was used to link cardiovascular and respiratory hospital admissions and total, cardiovascular and respiratory mortality with a pre-defined list of 16 PM10 and PM2.5 constituents. Lags 0 to 2 were examined. City-specific results were combined by random-effects meta-analysis. RESULTS Most of the elements studied, namely EC, SO4(2-), SiO2, Ca, Fe, Zn, Cu, Ti, Mn, V and Ni, showed increased percent changes in cardiovascular and/or respiratory hospitalizations, mainly at lags 0 and 1. The percent increase by one interquartile range (IQR) change ranged from 0.69% to 3.29%. After adjustment for total PM levels, only associations for Mn, Zn and Ni remained significant. For mortality, although positive associations were identified (Fe and Ti for total mortality; EC and Mg for cardiovascular mortality; and NO3(-) for respiratory mortality) the patterns were less clear. CONCLUSIONS The associations found in this study reflect that several PM constituents, originating from different sources, may drive previously reported results between PM and hospital admissions in the Mediterranean area.

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.

Time-resolved measurements of water-soluble ions and elements in atmospheric particulate matter for the characterization of local and long-range transport events.

Chemical composition of atmospheric PM(10) was determined at 2-h resolution during a 10-d field study carried out in the urban area of Rome, Italy. Extractable and residual fractions of elements were determined on 2-h samples by inductively coupled plasma mass spectrometry, a rather widespread analytical technique; daily chemical characterization of macro- and micro-components was also carried out and the mass closure was obtained. Interpretation of the variations in PM(10) composition was carried out in the light of the meteorological conditions and, in particular, of the mixing properties of the lower atmosphere, evaluated by monitoring natural radioactivity due to radon 222 decay. The combination of time-resolved sampling, chemical fractionation and monitoring of the dilution properties of the atmosphere allowed a reliable identification of long-range transport events and of local phenomena, which could not be detected by daily samplings. This kind of study can be effective for gathering detailed information about tracers at local scale, which are really valuable for interpreting the results of traditional low-resolution monitoring studies.

Field intercomparison exercise on nitric acid and nitrate measurement (Rome, 1988) : a critical approach to the evaluation of the results

Abstract A 5-day intercomparison of measurement techniques for nitric acid and particulate nitrate was carried out at the Area della Ricerca di Roma (Montelibretti, Rome, Italy) during September 18–24, 1988. Sixteen groups from eleven European countries participated in the experiment, intercomparing the performances of several denuder and filter pack systems. In order to obtain a better characterization of the performance of each technique, in addition to HNO 3 and NO 3 − field sampling, the protocol included HNO 3 determinations from a pure source and temporal self-consistency tests. Many ancillary measurements were also undertaken, which proved to be of help in the interpretation of the data. The evaluation of the results is not performed through a simple linear regression of the data, that is by assessing agreement or disagreement between pairs of methods, but by comparing the results obtained in both the additional tests and the field samplings with the predicted deposition pattern. Once the reliability of each single technique has been evaluated in the light of the potential interfering mechanisms, a comparison between the results yielded by groups using the same technique and, finally, different techniques is carried out. The application of these criteria to the data set gathered during the intercomparison shows that the diffusion techniques yield the most reliable results, while teflon-nylon filter packs do not allow a correct discrimination between nitric acid and nitrate, particularly in the presence of high ammonium nitrate concentrations. Filter packs using a cellulose prefilter are only able to measure total nitrate.

Short-term effects of particulate matter on mortality during forest fires in Southern Europe: results of the MED-PARTICLES Project

Background An association between occurrence of wildfires and mortality in the exposed population has been observed in several studies with controversial results for cause-specific mortality. In the Mediterranean area, forest fires usually occur during spring–summer, they overlap with Saharan outbreaks, are associated with increased temperature and their health effects are probably due to an increase in particulate matter. Aim and methods We analysed the effects of wildfires and particulate matter (PM10) on mortality in 10 southern European cities in Spain, France, Italy and Greece (2003–2010), using satellite data for exposure assessment and Poisson regression models, simulating a case-crossover approach. Results We found that smoky days were associated with increased cardiovascular mortality (lag 0–5, 6.29%, 95% CIs 1.00 to 11.85). When the effect of PM10 (per 10 µg/m3) was evaluated, there was an increase in natural mortality (0.49%), cardiovascular mortality (0.65%) and respiratory mortality (2.13%) on smoke-free days, but PM10-related mortality was higher on smoky days (natural mortality up to 1.10% and respiratory mortality up to 3.90%) with a suggestion of effect modification for cardiovascular mortality (3.42%, p value for effect modification 0.055), controlling for Saharan dust advections. Conclusions Smoke is associated with increased cardiovascular mortality in urban residents, and PM10 on smoky days has a larger effect on cardiovascular and respiratory mortality than on other days.

Extraction and analysis of fungal spore biomarkers in atmospheric bioaerosol by HPLC–MS–MS and GC–MS

Airborne microorganisms, as bacteria and fungi, are ubiquitous components of the atmospheric aerosol particles. In this paper, we report a method for the simultaneous extraction, purification, separation, identification and quantification of ergosterol, mannitol and arabitol as biomarkers of fungal spores in bioaerosol particles. After sampling by a low volume sampler, filters were spiked with mannitol-(13)C and dehydrocholesterol as internal standards. Samples were then extracted by accelerated solvent extraction using pure ethanol. The extract was then passed through an amino cartridge and divided in two parts: the apolar fraction, released from the cartridge, was subjected to liquid liquid extraction (by n-hexane), while polar compounds, retained by the cartridge, were eluted by a mixture of methanol-water. The two fractions were joined and analyzed by HPLC equipped with two different columns in series, and coupled to a triple-quadrupole mass spectrometer with Atmospheric Pressure Chemical Ionization source. In addition, the same fractions were analyzed, after derivatization, by GC-MS. The results obtained by the two techniques were finally compared, showing good agreement between them. Last, the contents of the three biomarkers have been estimated in three atmospheric samples collected in a suburban/rural site and, using literature conversion factors, correlated to fungal biomass.