1. Residence in a urban area close to a petrochemical complex and its impact on allergic respiratory diseases in Italian schoolchildren
F. Cibella, MD; G. Cuttitta, MD; S. Ruggieri, Ph.D.; G. Drago, Ph.D.; F. D’Aniello, Ph.D.; M. Melis, MD; S. Bucchieri, MD; S. La Grutta, MD; G. Viegi, MD
National Research Council of Italy, Institute of Biomedicine and Molecular Immunology, Palermo
N°1553 Abstract
Aim of the study was to evaluate the influence of living in an urban area close to a petrochemical complex on questionnaire-reported allergic respiratory diseases in children. Between March and December 2012 we evaluated 1,248 schoolchildren (628 M), aged yrs, selected from all the junior high schools of Gela (GE, 77,000 inhabitants/637 evaluated subjects), Mediterranean area of Southern Italy, and those of Niscemi (NI, 26,400/354), Mazzarino (MA, 11,800/133), and Butera (BU, 4,900/124), in rural areas respectively 15, 27, and 16 km far from GE. A petrochemical industry, operating since 1965, is located close to the Gela urban area. Parents fulfilled a respiratory questionnaire. Asthmatic bronchitis during the first 2 yrs of life was reported by 10.2 in GE, 8.2 in NI, 5.0 in MA, and 0.0% in BU (p=.033, 2 test). Rhinitis in the last 12 months was reported by 28.5 in GE, 15.5 in NI, 19.2 in MA, and 16.7% in BU (p=.0002). Doctor diagnosed asthma (ddA) was reported by 10.1 in GE, 7.7 in NI, 4.4 in MA, and 2.7% in BU (p=.014). Use of drugs intended for asthma therapy in the last 12 months was reported by 6.9 in GE, 5.2 in NI, 0.8 in MA, and 1.0% in BU (p=.011). In a logistic model, when correcting for parental atopy, passive smoke exposure, mould/dampness at home, personal history for rhinitis, and socioeconomic status, children living in GE showed an eightfold risk factor for ddA with respect to those living in BU (OR 8.2, IC , p=.04, p for trend .02). In conclusion, children living in a highly polluted area are at higher risk for developing allergic respiratory diseases.
Methods
Between March 2012 and February 2013, 1,325 schoolchildren (669 M), aged yrs, were selected from all the junior high schools of Gela (GE, 77,000 inhabitants/660 evaluated subjects), close to a petrochemical complex, and those of Niscemi (NI, 26,400/355), Mazzarino (MZ, 11,800/186), and Butera (BU, 4,900/124), in rural areas respectively 15, 27, and 16 km far from GE (Figure 1).
Parents of all children fulfilled a respiratory health questionnaire investigating the presence of respiratory symptoms and 1,191 (89.8%) questionnaires were returned for evaluation. We evaluated: asthmatic bronchitis during the first two years of life (AB), rhinitis in the last 12 months (R), doctor diagnosed asthma (ddA), and use of any drugs for asthma in the last 12 months (AT).
For further evaluation, outdoor measurements of airborne particulates with aerodynamic diameter<2.5 µm (PM2.5) were performed in 84 sites (42 in GE and 42 in BU, MZ and NI), for 48 hours, by gravimetric samplers (Silent Sampler, FAI Instruments Srl, Fonte Nuova, Italy) with 47 mm Teflon filters. PM2.5 mass concentration was determined by gravimetric procedure. Filters were also analyzed for PM metal content by ICP-OES (inductively coupled plasma optical emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry).
Results
1,191 questionnaires were evaluated. Among the different centers (Table 1) AB was reported by 8.7 in GE, 6.4 in NI, 3.6 in MZ, and 0.0% in BU (p=0.0016, Kruskall-Wallis test). R was reported by 28.9 in GE, 19.4 in NI, 18.3 in MZ, and 15.1% in BU (p=0.0002). In the selected subsample, ddA was reported by 9.6% in GE, 7.0 in NI, 4.3 in MZ, and 2.5 in BU (p=0.013). Finally, AT was reported by 6.7% in GE, 4.8 in NI, 1.2 in MZ, and 0.8 in BU (p=0.0039).
A multiple logistic model was used for evaluating the effect of city of residence on doctor diagnosed asthma, correcting for confounding factors: children living in GE – with respect to those living in BU – had an OR = 3.5 (IC , p=0.04, p for trend 0.02, Table 2).
We also investigated PM2.5 concentration: it was significantly higher in GE (p=0.0006, Figure 2). The airborne concentration of both Ni and V – usually considered markers of oil combustion – was significantly higher in GE (Figures 3 and 4). In Figure 5 the correlation between V and Ni is presented, showing that both metals may be attributed to similar sources.
Table 1 - Prevalence rates of Asthmatic Bronchitis in the first 2 years (AB), Rhinitis in the last 12 m, doctor diagnosed asthma (ddA) and use any drugs for asthma in the last 12 months (AT) in different centers. P values are reported (2 test)
Figure 2 - PM2.5 levels among different centers 10 20 30 40 50 BU MZ NI GE
PM2.5 (µg/m3)
p=0.0006
Figure 3 - Ni levels among different centers.
Nickel (ng/m3)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5 BU MZ NI GE
p=0.0002
Introduction
Symptoms of asthma and other chronic lung diseases are often precipitated by increased levels of air pollutants including particulates. The prevalence of allergic respiratory disease is high and continues to increase in populations of urban areas. A number of studies have demonstrated an association between respiratory symptoms, asthma diagnosis and residential proximity to industrial settlements as petrochemical plants.
Children living in an area close to the petrochemical plant, in Gela, Mediterranean area of Southern Italy, were studied and compared with those living in the rural areas of Butera, Mazzarino and Niscemi. We hypothesized that children exposed to pollutants from petrochemical plant would have increased prevalence of allergic respiratory diseases with respect to children living far from the polluted area.
Aim of this study was to determine the relationship between prevalence of respiratory symptoms and refinery proximity.
AB (%)
R (%)
ddA (%)
AT (%) GE
8.7
28.9
9.6
6.7 NI
6.4
19.4
7.0
4.8 MZ
3.6
18.3
4.3
1.2 BU
0.0
15.1
2.5
0.8
p=0.0016
p=0.0002
p=0.013
p=0.0039
Figure 4 - V levels among different centers.
Vanadium (ng/m3) 2 4 6 8 10 12 14 BU MZ NI GE
p<0.0001
Vanadium (ng/m3)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5 2 4 6 8 10 12 14
Ni = * V; p<0.0001
Nickel (ng/m3)
Table 2 - Multiple logistic model for evaluating the effect of place of residence on doctor diagnosed asthma (ddA) OR
95% Lower
95% Upper
Male Gender
1.88
1.15
3.01
Parental atopy
1.27
0.78
2.06
Environmental tobacco smoke
0.91
0.48
1.72
Mould/dampness at home
2.42
1.34
4.39
Socio-economic status
1.17
0.70
1.95
Rhinitis
3.28
2.02
5.32
Residence in MZ (Ref. BU)
1.47
0.35
6.15
Residence in NI (Ref. BU)
2.33
0.65
8.32
Residence in GE (Ref. BU)
3.56
1.07
11.81
Figure 5 - Correlation between outdoor
concentration of Nickel and Vanadium
Conclusions
With respect to rural areas, the prevalence of investigated respiratory diseases in a urban area close to petrochemical plant was higher.
In particular, the risk for ddA in Gela was more than threefold with respect to Butera.
Similarly, airborne concentration of PM2.5 and metals such as V and Ni – previously associated with respiratory disorders – were higher in the polluted area.
This could explain, in part, the different prevalence observed in the different centers.
Figure 1 - Geographical localization of the investigated areas
Funded by Operational Cross-border Program Italy-Malta