Daniele Balducci

Sources and atmospheric concentrations of polycyclic aromatic hydrocarbons and heavy metals in two Italian towns (Genoa and La Spezia)

The same sampling and analytical methods were used to compare atmospheric pollution due to polycyclic aromatic hydrocarbons (PAHs) and heavy metals (Tl, Pb, Mn, Fe, Cr, V, Zr, Ni Cd) in two towns in Italy, Genoa and La Spezia, whose populations are 746, 785 and 112,602 respectively. Knowledge of the organic and inorganic composition of airborne particulates permits a reliable identification of the main sources of pollution which is required in order to identify populations at risk. In the urban area of Genoa and in La Spezia, traffic appears to provide a diffuse source of carcinogenic and toxic compounds in the atmosphere producing high and constant exposures to PAHs and lead along busy streets. In Genoa approximately 70,00 people (10% of residents) are considered to be exposed to the highest concentrations of toxic and cancerogenic pollutants emitted from this source. The highest daily PAH concentrations were found in the industrial areas; in Genoa, coke ovens were identified as the main localised sources of these compounds. According to meteorlogical and orographic characteristics for this area, for approximately 25,00 people (3% of the general population) may be exposed to pollutants emitted from this source over a maximum period equivalent to approximately 3 months each year. The highest individual doses of PAHs due to urban pollution inhaled by the population of Genoa and La Spezia were comparable to those produced by high exposure to passive smoke; the exposure to carcinogenic metals (Cr, NI, Cd) was relatively low. The mean concentrations of the analysed pollutants appeared to depend strictly on urban characteristics; no correlations were found with the size of the town.

Preliminary evaluation, using passive tubes, of carbon monoxide concentrations in outdoor and indoor air at street level shops in Genoa (Italy)

Abstract Preliminary information on carbon monoxide (CO) concentrations (exposure time: 8 h) both inside and outside 38 randomly selected shops situated on four heavy traffic streets of Genoa was obtained using passive diffusion tubes. Reproducibility and accuracy of this analytical method were tested in real outdoor urban conditions and found within 25%; the detection limit was 1 mgm−3 of CO. The highest mean CO concentrations (15.8 ± 2.2 mgm−3) were found inside shops on Balbi street, a narrow “canyon street”. Only in two small shops and two bars (both with many smokers) and in a delicatessen, were indoor CO concentrations significantly higher than outdoor values. The mean outdoor CO concentrations (mgm−3) along the four streets considered (XX Settembre, Balbi, Rolando, Fillak) were 7.4 ± 2.2; 14.5 ± 8.7; 5.8 ± 0.4; 10.5 ± 3.7, respectively. No statistical difference was found, comparing the mean indoor CO concentration with the mean CO outdoor value, measured simultaneously along the sidewalks of each street. CO concentrations in 10 shops without smokers and the nearest outdoor measurements were linearly correlated (r = 0.99; p

Air Quality Standard for Benzo(a)pyrene (BaP) in Genoa (1994-1995)

Abstract Mean benzo(a)pyrene concentrations were evaluated in four Genoan sampling sites. It was verified the respect of air quality standard recently introduced into Italian legislation (2.5 ng/m3 from 1996 and 1 ng/m3 from 1999). In sites along heavy traffic streets the mean BaP concentrations were about 2 ng/m3; on a buildings roof, 300 metres from a coke oven, the mean BaP concentration was 14 ng/m3.

Exposure to airborne cadmium in some Italian urban areas

Abstract Three hundred and ninety-five daily airborne particulate samples collected in urban and industrial areas of Genoa and La Spezia, and 46 samples from urban areas of a further 16 Italian towns, provide information for the mean airborne cadmium exposure. The geometrical means for cadmium were the highest near the municipal urban waste incinerator of Genoa and in the industrial area of La Spezia (respectively 9.0 and 5.1 ng/m3). After closure of the incinerator a significant decrease (−96%) in cadmium around the plant was found. In all the urban areas, mean cadmium concentrations ranged from 1.5 to 2.8 ng/m3 and at the rural site of La Spezia the mean cadmium concentration was 0.9 ng/m3. These results agree with those found for other, similar European areas. Traffic and urban waste incineration were identified as the main sources of cadmium.

Metals in airborne particulate as polynuclear aromatic hydrocarbons (PAH) source indicators: Preliminary results†

This preliminary report wants to evaluate if relative abundance of certain metals (Pb, V, Ni, Cr) in the particulate may be used as a specific indicator or tracer of the several sources that in an urban area can emit PAHs. This approach may give more accurate information as chemical reactivity of PAHs in the atmosphere makes it difficult to predict possible modifications of their absolute and relative concentrations. This method was used to identify possible origin of atmospheric pollution which occurred at Murta, a little town on the hills, near Genova. The airborne particulate collected in this place was relatively low in Pb and rich in V. Therefore, traffic was excluded as main pollution cause, some industrial process burning oil, being more open to suspicion. V and Ni concentrations showed a good correlation and according to their ratio at least two different types of particulate were present in the atmosphere of Murta. They were probably of different origins depending on anemological conditions diffi...

Effect of sun light and temperature on concentration of Pyrene and Benzo(a)pyrene adsorbed on airborne particulate

Poly Aromatic Hydrocarbons (PAH) exposed to sun light undergo photodegradation with half‐life ranging from 1 hour, in summer, to days, in winter. This difference is mainly due to variation in sun light intensity. A simple extrapolation of experimental results obtained in laboratory or in controlled situations, suggested that during the permanence in the atmosphere, the actual concentration of PAH adsorbed to airborne particulate and exposed to sun light, may follow the equation: lnPAH = PAHo‐bI where PAH is the concentration after a stated time from emission, PAHo is the concentration of PAH at the moment of emission, I is the mean sun light intensity and b is a constant correlated to the mean residence time of airborne particles in the atmosphere. With our research we have verified this hypothesis. In fact concentration of Pyrene and Benzo(a)pyr‐ene on airborne particulate collected in Genova near and far from the main source of these compounds (traffic) was linearly correlated with mean sun‐light intens...

Temporal and spatial variations of polycyclic aromatic hydrocarbon concentrations around a coke oven plant

From 1995 to 2004, in Genoa, Italy, daily concentrations of twelve polycyclic aromatic hydrocarbons (PAHs) were measured in particulate phase (PM10), around a coke oven plant in operation from the 1950s and closed in 2002. The study permitted to identify the coke oven as the main PAH source in Genoa, causing constant exceeding of benzo(a)pyrene (BaP) air quality target (1.0 ng/m3) in the urban area till 1,900 meters distance downwind the plant. For this reason the plant was closed. Distance and daily hours downwind the coke plant were the main sources of variability of toxic BaP equivalent (BaPeq) concentrations and equations that best fitted these variables were experimentally obtained. During full plant activity, annual average BaPeq concentrations, measured in the three sampling sites aligned downwind to the summer prevalent winds, were: 85 ng/m3 at 40 m (site 2, industrial area), 13.2 ng/m3 at 300 m (site 3, residential area) and 5.6 ng/m3 at 575 m (site 4, residential area). Soon after the coke ovens closure (February 2002) BaPeq concentrations (annual average) measured in residential area, decreased drastically: 0.2 ng/m3 at site 3, 0.4 ng/m3 at site 4. Comparing 1998 and 2003 data, BaPeq concentrations decreased 97.6% in site 3 and 92.8% in site 4. Samples collected at site 3, during the longest downwind conditions, provided a reliable PAH profile of fugitive coke oven emissions. This profile was significantly different from the PAH profile, contemporary found at site 5, near the traffic flow. This study demonstrates that risk assessment based only on distance of residences from a coke plant can be heavily inaccurate and confirmed that seasonal variability of BaPeq concentrations and high variability of fugitive emissions of PAHs during coke oven activities require at least one year of frequent and constant monitoring (10-15 samples each month). Implications: Around a coking plant, polycyclic aromatic hydrocarbons (PAHs), concentrations depend mainly on downwind hours and distance. Equations that best fit these variables were experimentally calculated. Fugitive emissions of an old coke oven did not comply with the threshold BAP air concentration proposed by the World Health Organization (WHO), up to 1,900 m distance. The study identified the PAH profile of fugitive emissions of a coke oven, statistically different from the profile of traffic emissions. During its activity, in the Genoa residential area, 575 m away from the plant, 92.8% of found PAHs was due to coke oven emission only. Supplemental Materials: Supplemental materials are available for this article. Go to the publishers online edition of the Journal of the Air & Waste Management Association for information about samples analyses, statistical analyses and regression models figure.

Catalytic Converters and PAH Pollution in Urban Areas

Every organic substance containing carbon and hydrogen yields a large number of polycyclic aromatic hydrocarbons (PAH) during incomplete combustion or pyrolysis or during the formation of petroleum and coal. PAHs are included in a class of chemical compounds characterised by two or more condensed aromatic rings. Several PAHs have been classified by the International Agency for Research on Cancer (IARC) as probable or possible human carcinogens (IARC, 1987). Due to their carcinogenic and mutagenic effects, sixteen PAHs were included in the US EPA priority pollutant list (Yan, Wang et al., 2004); between them, benzo(a)pyrene (BaP), with five condensed aromatic rings, is recognised as the PAH with the highest carcinogenic potency and is considered to be an indicator of the presence of the PAH group in environmental matrices: air, water, soil, food. In fact in every analysed mixture, the BaP concentration fits linearly with the concentrations of other semi volatile PAHs, prevalently adsorbed to airborne particulate matter.