Levels and sources of polynuclear aromatic hydrocarbons in the Genoa-Cornigliano area A. Cecinato, M. Repetto, E. Guerriero & I.

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1 Levels and sources of polynuclear aromatic hydrocarbons in the Genoa-Cornigliano area A. Cecinato, M. Repetto, E. Guerriero & I. Allegrini Abstract A monitoring campaign of atmospheric PAH and nitrated derivatives of PAH (N- PAH) was carried out in July '97 in Genoa-Cornigliano. In fact, this area was regarded as representative of the densely inhabited ones of Italy, that are affected by strong emission sources. Four sites were investigated, two of them located inside the coke plant of a steel industry, and a third one near the border of the above plant, in a densely populated zone; the last site was located in a villa park, far from any emission source. The nature and concentrations of both the PAH and N-PAH identified reveal high levels of carcinogenic components in the air and are also indicative of a strong impact of industrial emission and a strict dependence of air quality on wind direction; on the other hand, quite low seems to be the effect of air photochemistry in the generation of N-PAH. 1 Introduction In the frame of a Grant supported by our Ministry of the Environment, an investigation was performed by IIA, aimed to standardise methodologies applied to determine participated organic components of the atmosphere capable to affect the air quality. These methodologies were applied to determine PAH and N-PAH levels in the Genoa-Cornigliano area, that is representative of urban zones affected by strong industrial emission. For this purpose, a monitoring campaign was carried out during July '97.

2 588 /*,'; 2 Experimental Four sites were investigated, representative of different typologies: two of them were located inside the coke plant of a big steel industry (Acciaierie Riva), respectively near stack tower no. 1 (Northern side) and distillation batteries (Southern side); a third one was on the top of buses garage of the public transport firm of Genoa (ATM - Azienda Tramviaria Municipale), just on the border of the coke plant and in the middle of a densely populated area; and the last one was in the park garden of Villa raggio, quite far from any pollution source and then representative of background levels of pollutants in the air investigated. PAH and N-PAH were determined by subjecting inhalable air particles to a dedicated procedure, allowing also the investigation of the aliphatic fraction, that gave useful information about the nature of sources. Inhalable particulates were collected onto 47 mm o.d. PTFE membranes by means of "PM-10" samplers at flow rate set at 16 L/min. Samplings started at 9.00 in the morning and lasted 24 h. The participate organic matter (POM) was soxhlet-extracted by using a dichloromethane and acetone mixture (5:1), then five different classes of compounds were separated by means of both LC, Alumina column, and HPLC, normal phase (i.e. Alipahtics, PAH, N-PAH, Oxigenated components, Polar and acidic species). Al fractions were analysed by capillary GC, by splitless-mode injection and elution through a DB-5-type column; n-alkanes were evaluated by HRGC-FID, whereas HRGC-MS (operated in multiple ion detection) was necessary for PAH and N-PAH determinations. Among PAH, our investigation was focussed onto congeners recognized by IARC ' as possible or probable carcinogens; also methyl-derivatives were evaluated, because of their toxic properties. The occurrence of N- PAH in the atmosphere needed larger amounts of participate extract, therefore it was investigateed only for four days at the ATM site, when a high-volume sampling was carried out in parallel. 3 Results Table 1 shows n-alkanes, PAH and N-PAH concenrtations recorded at ATM site on July, 15th to 18th. Both the composition and levels of the aliphatic fraction were typical of the areas exposed to intensive vehicle emission; the monomodal distribution of n-alkanes had its maximum in correspondance of 23; only a minor contribution seemed to outcome from biogenic emission (CPI]5 close to 1). Both benz(a)pyrene (BaPY) and total PAH reached high aerometric levels (see Table 2); in particular,

3 589 mean BaPY (7.3 ng*m~*) duty exceeded Italian guideline value fixed by Ministero dell'ambiente* (i.e. 2.5 ng*m~*). However, two daily series could be distinguished, being characterized by different levels of PAH; in fact, the 15th and 16th July were representative of low pollution (1st series; it also occurred on the 19th and 20th July), whereas the 17th and 18th belong to the 2nd series (high pollution; also on the 21th and 22th). N-PAH reached higher concentration on the same days of PAH, whereas aliphatic components followed an opposite trend. Figures 2 and 3 allow to relate daily trends of POM components to the meteorology evolution; higher concentrations of pollutants seemed to be concurrent with high air humidity and strictly depending on wind direction. Table 3 shows PAH aerometric concentrations observed at Villa Raggio site. BaPY levels were everyday below Italian guideline values for urban areas and PAH evolution was different from that recorded at ATM site; benz(a)pyrene/benz(e)pyrene ratio R, which is an index of "agging" of air particles (Kamens et al. \ was also low. These observations seem to demonstrate that Villa Raggio site did not possess own nor was subjected to near PAH-emitting sources. Atmospheric PAH recorded inside the steel plant at Northern site (NS) are reported in Table 4; those recorded at Southern site (SS), not reported here, were some lesser. PAH concentrations, expressed as BaPY, hevily exceeded 2.5 ng*nr\ At NS levels of PAH were quite constant and always higher than at SS. While R ratio was close to one at NS, it was close to 0.7 at SS. Instead, sedimentables seemed to contain higher amounts of PAH at SS than at NS and BaPY/BePY ratio exceeded 1.0. The composition of PAH fraction of air particles collected at NS, SS and ATM was similar to that of sedimentables, confirming that the steel plant was the main source of pollution at ATM site; instead, at Villa Raggio it was affected by photo- or red/ox-chemistry developing in the air. That can be highlighted by considering the index defined as "carcinogenic equivalents of benz(a)pyrene" (BaPE) (Cecinato *), calculated through the actual cocenntrations and "carcinogenicity factors relative to BaPY" of individual PAH, and also its ratio to BaPY (RJ: Re ratio was constant at NS and SS; at ATM it was peculiar of the heavy polluted areas and reached higher values in correspondance of the 1st daily series; at Villa Raggio Re trend did not correlate with that recorded at ATM. 4 Conclusions In spite of the brevity of the monitoring campaign performed, some important results were obtained. In particular, the organic pollutants levels observed seem to indicate that:

4 590 X/ i - the area of Genoa-Cornigliano was affected by high levels of carcinogenic PAH, in fact, mean concentation of BaPY was larger than 7 ng*m"~\ that is three times the guideline value of urban air quality established by the Ministry of Environment of Italy; ii - the aerometric concnetrations of PAH strongly depended onto the meteorology dominating the area investigated; in particular, wind direction widely affected the levels of pollutants; iii - the relative contribution of photochemical reactions to occurrence of toxic pollutants was poor; direct emission seemed to dominate with respect to secondary pollutants, and photochemically-originated N- PAH were quite low; iv - levels of PAH and N-PAH at Villa raggio were low; v - the conrtibution of biogenic emission to the organic content of soot was scarce; vi - the steel plant seemed to appear the main pollution source at Geoa- Cornigliano; nevertheless, vehicle traffic was responsible for high concentrations observed of PAH and N-PAH, whenever northern winds prevented the fallout of industrial emission onto this area. 5 Acknowledgments Authors are grateful to Centre Operative Provinciate of Amministrazione Provinciate di Geneva for supplying of meteo data and collection of participates at Villa Raggio site, and to Management of Acciaierie di Cornigliano for collection of sedimentables and soot inside the industrial plant. We want also to tank the Azienda Tramviaria Municipalizzata Genovese for hospitality and Mr. A. Brachetti for technical adsistance. This research was supported by Ministero delpambiente of Italy. References [1] International Agency for the Research on Cancer I ARC, Overall Evaluation of Carcinogenicity: an Updating of IARC Monographs Volumes 1 to 42 (Monographs on the evaluation of carcinogenic risk for humans). Suppl. 7, IARC Ed., Lyon, 1987.

5 [2] Ministero dell'ambiente, 25 novembre 1994, Aggiornamento delle norme tecniche in materia di limit! di concentrazione e di livelli di attenzione e di allarme per gli inquinanti atmosferici nelle aree urbane e disposizioni per la misura di alcuni inquinanti di cui al DM 15 aprile 1994 (Testo e Allegato VII), Gazzetta Ufficiale della Repubblica Italiana, Suppl. 290, 13th December, [3] Kamens, R.M., Guo, Z., Fulcher, J.N. & Bell, D.A., Influence of humidity, sunlight and temperature on daytime decay of polycyclic aromatic hydrocarbons on atmospheric soot particles, Environ. Sci Technol.,22,pp , [4] Cecinato, A., Polynuclear Aromatic Hydrocarbons (PAH), Benz(a)pyrene (BaPY) and Nitrated-PAH (N-PAH) in suspended participate matter. (Proposal for the revision of the Italian Reference Method), Annali di Chimica, 87, pp , Figure 1 - Map of Genoa and of Cornigliano area with sampling sites of atmospheric soot. 1: Acciaierie Riva, northern site NS; 2: Acciaierie Riva, southern site SS; 3: Buses garage, ATM; 4: Villa Raggio.

6 592 Air Pollution Table 1 - Aerometric concentrations of n-alkanes, PAH and N-PAH at ATM site. Genova-Cornigliano, 15 to 18 July, Hi.Vol. sampling. date species H-C18 n-c19 n-c20 n-c21 n-c22 n-c23 n-c24 n-c25 n-c26 n-c27 n-c28 n-c29 n-c30 n-c31 D-C32 n-c33 n-c34 Total n-alkanes Fluoranthene Pyrene Benz(a)anthracene Chrysene Benz(b)f!uoranthene Benz(k)fluoranthene Benz(e)pyrene Benz(a)pyrene lndeno(1.2.3-cd)pyrene Dibenz(ah)anthracene Benz(ghi)perylene Total PAH 2-Nitrofluoranthene 1-Nitropyrene 2-Nitropyrene Total N-PAH 15th July , th July th July th July ,

7 Table 2 - Aerometric concentrations of PAH at ATM site. Genova-Cornigltano, July PM-10 sampling (16 L/min). date species Fluoranthene Pyrene Benz(a)anthracene Chrysene Benz(b)fluoranthene Benz(k)f!uoranthene Benz(e)pyrene Benz(a)pyrene lndeno(1.2.3-cd)pyrene Dibenz(ah)anthracene Benz(ghi)peryiene Total PAH Methyl-PHE/AN Methyl-FA/PY Methyl-BaAN/CHR Methyl-BFA/BPY Total PAH + Methyl-PAH BaPE BaPE/BaPY 15th July c ([ th July th July th July th July , th July th July th July

8 Table 3 - Aerometric concentrations of PAH at Villa Raggio site. Genova-Cornigliano, July PM-10 sampling (16 L/min). date species Fluoranthene Pyrene Benz(a)anthracene Chrysene Benz(b)fluoranthene Benz(k)fluoranthene Benz(e)pyrene Benz(a)pyrene lndeno(1.2.3-cd)pyrene Dibenz(ah)anthracene Benz(ghi)perylene Total PAH Methyl-PHE/AN Methyl-FA/PY Methyl-BaAN/CHR Methyl-BFA/BPY Total PAH + Methyl-PAH BaPE BaPE/BaPY 16th July c (ng/nr>3) th July th July th July th July th July th July

9 Table 4 - Aerometric concentrations of PAH at Northern sampling site Inside Accialerie Riva coke plant. Genova-Cornigliano, July PM-10 sampling (16 L/mln). date species Fluoranthene Pyrene Benz(a)anthracene Chrysene Benz(b)fluoranthene Benz(k)fluoranthene Benz(e)pyrene Benz(a)pyrene lndeno(1.2.3-cd)pyrene Dibenz(ah)anthracene Benz(ghi)perylene Total PAH Methyl-PHE/AN Methyl-FA/PY Methyl-BaAN/CHR Methyl-BFA/BPY Total PAH + Methyl-PAH BaPE R (BaPE/BaPY) 16th July th July 18th July , th July th July th July ng/rr> th July th July I

10 596 Air Pollution Table 5 - Mean PAH concentrations in sedimentables (ug/g) collected at NS inside Acciaierie Riva. Genova-Cornigliano, July Fluoranthene Pyrene Benz(a)anthracene Chrysene Benz(b)fluoranthene Benz(k)fluoranthene Benz(e)pyrene Benz(a)pyrene lndeno(1.2.3-cd)pyrene Dibenz(ah)anthracene Benz(ghi)pery!ene Methyl-PHE/AN Methyl-FA/PY Methyl-BaAN/CHR Methyl-BFA/BPY Total PAH PAH + Methyl-PAH I Figure 2 - BaPY, BaPE and R(BaPE/BaPY). Genova-Cornigliano, ATM site date, Juty 1997 ibapy ( 1 BaPE -^- R(BaPE/BaPY) Figure 3 - Meteorological parameters recorded at Genova-Cornigliano a "O 150 ~ date, July 1997 I wind speed ( maanrel humidtty max. wind direction 50 ^