Vanes Poluzzi

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.

Comparison of two different inductively coupled plasma mass spectrometric procedures and high-performance liquid chromatography with electrochemical detection in the determination of iodine in urine

A comparison between two ICP-MS methods and HPLC with electrochemical detection (ED) for the determination of iodine is described. The first ICP-MS method involves 10-fold dilution with water using Rh as internal standard and the calibration graph was obtained with a synthetic urine. In the second ICP-MS method the sample preparation provided a 5-fold dilution with water using In as internal standard and adding nitric acid and the calibration graph was obtained by making additions to a pool of human urine samples. In the HPLC method, the urine was previously purified from organic substances through an SPE C18 column and the final portion was collected. The chromatographic column used was a C18 reversed-phase column and a silver working electrode was used versus a Pd/Pt reference electrode for ED. The calibration graph was obtained with a synthetic urine. The results show that the two ICP-MS methods are comparable in terms of analytical parameters such as precision and limit of detection. Good agreement between both ICP-MS procedures and HPLC–ED was also obtained, although the limit of detection was higher in HPLC–ED and the linear dynamic range was wider in both ICP-MS methods.

Identification of pathway-based toxicity in the BALB/c 3T3 cell model

The particulate matter represents one of the most complex environmental mixtures, whose effects on human health and environment vary according to particles characteristics and source of emissions. The present study describes an integrated approach, including in vitro tests and toxicogenomics, to highlight the effects of air particulate matter on toxicological relevant endpoints. Air samples (PM2.5) were collected in summer and winter at different sites, representative of different levels of air pollution. Samples organic extracts were tested in the BALB/c 3T3 CTA at a dose range 1-12m(3). The effect of the exposure to the samples at a dose of 8m(3) on the whole-genome transcriptomic profile was also assessed. All the collected samples induced dose-related toxic effects in the exposed cells. The modulated gene pathways confirmed that toxicity was related to sampling season and sampling site. The analysis of the KEGGs pathways showed modulation of several gene networks related to oxidative stress and inflammation. Even if the samples did not induce cell transformation in the treated cells, gene pathways related to the onset of cancer were modulated as a consequence of the exposure. This integrated approach could provide valuable information for predicting toxic risks in humans exposed to air pollution.

Determination of lead in gallium arsenide by graphite furnace atomic absorption spectrometry with an ammonium chloride–chromium(III) chloride chemical modifier

A method is described for the determination of trace amounts of lead in gallium arsenide by graphite furnace atomic absorption spectrometry (GFAAS) using chemical modification. The sample is dissolved in hydrochloric acid and bromine, with the addition of ammonium chloride plus chromium(III) chloride as the chemical modifier. The ashing and atomization steps were optimized. The detection limit was found to be 5 ng g–1 for peak height measurements and 13 ng g–1 for peak area measurements. The reproducibility of the over-all procedure is 2–10% depending on the lead content. The results were in agreement with those obtained by anodic stripping voltammetry.

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

Determination of tin in indium phosphide by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry

Two independent methods for the determination of tin in tin-doped indium phosphide were developed and compared. The electrothermal atomic absorption spectrometry (ETAAS) method utilized both platform atomization and a chemical modifier composed of orthophosphoric acid and magnesium nitrate. The detection limit (6 sb) is 5.0 µg g–1 for a 250 mg sample. The inductively coupled plasma mass spectrometry (ICP-MS) method monitored the 120Sn isotope and a typical detection limit (6sb) of 0.5 µg g–1 for a 20 mg sample was obtained. The observed range is 0.2–0.75 µg g–1 depending on the instrumental stability and response. The matrix effect was investigated in both methods, and the results indicated that matrix-matched calibration standards should be used. Indium phosphide wafers, obtained from a single crystal grown from a tin-doped melt, were analysed by using both methods to determine the tin content and the change in concentration along the crystal. Results having means that did not differ significantly (P=0.05) were achieved. Both the ETAAS and ICP-MS techniques were useful in determining tin in the tin-doped InP, however ICP-MS without internal standardization was less precise. When real samples containing 35–149 µg g–1 of Sn were analysed, the relative standard deviation was in the range 12.9–4.3% for ICP-MS and 3.4–2.0% for ETAAS.

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.

Loss processes affecting submicrometer particles in a house heavily affected by road traffic emissions

ABSTRACT The fraction of outdoor aerosol that penetrates into indoor environments plays an important role in determining the contribution of outdoor particles to the total lung dose of particles in human exposure. The objective of this study was to investigate the physical processes affecting migration of outdoor traffic particles into indoor environments. Particle number size distributions were measured by a fast mobility particle sizer system in both indoor and outdoor environments of a house located in close proximity to a busy street in Bologna (Italy) in the period February–April 2012. Indoor to outdoor (I/O) ratios for submicron particle number concentrations showed strong dependence on particle size and meteorological conditions. The loss rates of particles due to deposition, coagulation, and evaporation were determined using dynamic mass balance and coagulation models. Higher loss rates were found for small particles (nucleation and Aitken mode) indoors than for larger particles (accumulation mode). The coagulation and evaporation processes made a significant contribution to the loss of traffic nanoparticles indoors, especially during the day time. Application of positive matrix factorization to the indoor and outdoor particle size distributions showed a substantial loss of traffic-generated nucleation mode particles in the indoor environment, with evaporation playing a major role. Copyright

Comparison between two different nanoparticle size spectrometers.

A commercial differential mobility particle sizer (DMPS), long and medium column DMA (Grimm Aerosol Technik L-DMA model 5.400; M-DMA model 5500), condensation particle counter (CPC, Grimm Aerosol Technik 5.403), and a fast mobility particle sizer (FMPS-TSI, model 3091), were deployed to determine the size distributions of ultrafine particles. Comparisons were performed using atmospheric aerosol, as well as laboratory aerosol generated by nebulizing Milli-Q water (Millipore Corporation) and a water suspension of Fe2O3 in a Collison type atomizer. Results show that the DMPS generally measured higher particle number concentrations than the FMPS, above all for atmospheric aerosol compared to laboratory generated aerosol. With regard to size distribution, in both the atmospheric and laboratory-generated aerosols, the FMPS always showed a small peak around 10 nm, which was not shown by the M-DMPS. The agreement of the particle number concentration between the DMPS and FMPS was better in the 25–116 nm range for atmospheric aerosol, and in the 10–65 nm range for laboratory-generated aerosols. Since these instruments are scheduled to be run for air quality measurements and not only aerosol research purposes, there is an urgent need to establish working protocols in compliance with requirements with ISO 15900 requirements. Implications: Epidemiological studies have shown that high ultrafine particulate concentrations are associated with an increase in mortality. Measuring exposure against mass alone is not sufficient, but it is also necessary to consider exposure against number concentration. Therefore, continuous measurements of aerosol size and number concentrations are important. This paper provides a comparison between two different nanoparticle size spectrometers widely used in air quality measurements. We found significantly different total number particle concentrations and size distributions in both laboratory-generated and atmospheric aerosols. Results show that the DMPS generally measured higher particle number concentrations than the FMPS. Since these instruments are scheduled to be run for air quality measurements and not only aerosol research purposes, there is an urgent need to establish working protocols in compliance with ISO 15900 requirements.

Air quality assessment in Bologna by an urban dispersion model

An urban dispersion model (ADMS?Urban) was run to calculate PM10 and NO2 concentration during a one-year period, on a district of Bologna, Italy. Moreover, the exposure of 333 children was estimated using model outputs corrected with observations. The model was able to correctly simulate the long-term statistical properties of roadside observed concentrations (such as annual mean and frequency distribution), but it failed in reproducing instantaneous values. The proposed methodology is of easy implementation, and it could be useful to identify areas with high pollutant levels, to estimate population exposure and to evaluate the benefit of pollution reduction policies.